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Vlerkies
May-20-2014, 04:17
-full modelling of negative g effects on the carburetor (currently it is modeled as if it already had mrs shillings orifice, the engine cuts out but doesn't shut off)


Might I suggest Sir, that you don your flak jacket for that one, that's gonna get the RAF frothing at the mouth. :)

The standard evasive maneuver for Hurri's these days seems to be a neg g push forward followed by a hard pull back without missing a beat.

http://youtu.be/ll7OqalJiAE

Watch from 1:40 on, he did it a few times. The 1 at 2:22 was quite impressive.

Excuse my submarine mode at the end. :crazyeyes:

Robo.
May-20-2014, 04:36
Might I suggest Sir, that you don your flak jacket for that one, that's gonna get the RAF frothing at the mouth. :)

The standard evasive maneuver for Hurri's these days seems to be a neg g push forward followed by a hard pull back without missing a beat.

Have you tried it yourself in a Hurricane (or a Spitfire) and did you manage not to miss a beat? :salute: From my experience, although it's a legit and effective last resort maneuver, it is not advisable at all as you lose considerable amount of speed and E and it takes a while for the engine to catch up again. That guy in the video was not too bad in defensive flying considering the situation he got himself into (low and slow).

Also, the neg G behaviour of the Merlin engines modeled in game has been revised exactly after historical specifications in the TF patches.

(hnbdgr, you are also rather wrong in your 'Mrs Shilling ocrifice statement', the engine would not 'cut' with the ring installed providing you'd be flying at full throttle. It was preventing the carburator issue on one specific setting, nothing like what we have in CloD. Just for the record, I don't want to get off topic.

I am all for more burning RAF and historical ammo settings :thumbsup:

92 Sqn. Philstyle (QJ-P)
May-20-2014, 04:45
without missing a beat.
:

looks to me like he shed a crap load of airspeed by doing that... hardly "missing a beat"

Vlerkies
May-20-2014, 04:46
Robo, I haven't seen many RAF planes on my tail doing half rolls when I try escape from high alt with neg G, they just follow. I will keep my eyes out though. ;) probably just doing it wrong.

Vlerkies
May-20-2014, 04:48
looks to me like he shed a crap load of airspeed by doing that... hardly "missing a beat"]
Considering the turn he pulled you would expect him to shed the speed.

He is a good pilot, a sqn mate, and this is not meant to detract from anyone's flying abilities jbtw

92 Sqn. Philstyle (QJ-P)
May-20-2014, 04:55
you can even get the merlin to cut out (fuel starvation) with trim - try it. it's pretty sensitive to the neg-G.

hnbdgr
May-20-2014, 05:00
Also, the neg G behaviour of the Merlin engines modeled in game has been revised exactly after historical specifications in the TF patches.

(hnbdgr, you are also rather wrong in your 'Mrs Shilling ocrifice statement', the engine would not 'cut' with the ring installed providing you'd be flying at full throttle. It was preventing the carburator issue on one specific setting, nothing like what we have in CloD. Just for the record, I don't want to get off topic.

I have to say I have only limited knowledge of this, but it was my understanding that the engine could seize or "hydrolock" would occur if sustained negative g was in play. I trust you guys have better knowledge in this are then I do of course, but I was not able to kill my engine in a spit or a hurri in a prolonged negative g maneuver, neither does it ever require a restart, it always simply jumps on when positive g is restored. Sorry for Off-topic, but it is quite an interesting topic.

92 Sqn. Philstyle (QJ-P)
May-20-2014, 05:02
I have to say I have only limited knowledge of this, but it was my understanding that the engine could seize or "hydrolock" would occur if sustained negative g was in play.

Why not just try it?
8 or so seconds of inverted (slightly neg-G) flight completely kills the engine, requiring mid-air restart.

Robo.
May-20-2014, 05:20
Robo, I haven't seen many RAF planes on my tail doing half rolls when I try escape from high alt with neg G, they just follow. I will keep my eyes out though. ;) probably just doing it wrong.

I suggest you jump in a Spitfire or a Hurricane and try following a 109 that evades in neg-G and you will see yourself. :thumbsup: If you see the RAF guy behind you climbing as you dive, then watch out, he probably knows what he's doing.

hnbdgr - if you're interested in the topic, it's been discussed in depth in here as well as on 1c forums a while ago.

JG4_sKylon
May-20-2014, 05:26
Robo, I haven't seen many RAF planes on my tail doing half rolls when I try escape from high alt with neg G, they just follow. I will keep my eyes out though. ;) probably just doing it wrong.

+1
Spits follows almost everytime when diving away with closed Radiators, full throttle and WEP.
Thought it was "the" escaping maneuver for 109s, 2 days ago a spit even closed the gap in a dive.

Maybe i am doing something wrong, just reporting my experience of the last sorties.

Robo.
May-20-2014, 05:26
]
Considering the turn he pulled you would expect him to shed the speed.

He is a good pilot, a sqn mate, and this is not meant to detract from anyone's flying abilities jbtw

So what exactly is wrong with that particular fight in the video? I would do exactly the same in his situation ans so would you. There is nothing that wasn't possible in real life as far I can see.

Robo.
May-20-2014, 05:31
+1
Spits follows almost everytime when diving away with closed Radiators, full throttle and WEP.
Thought it was "the" escaping maneuver for 109s, 2 days ago a spit even closed the gap in a dive.

Maybe i am doing something wrong, just reporting my experience of the last sorties.

Have you got a video or a track perhaps? How far was he, when you started diving, how fast were you and how fast was he? What was the altitude and what was the dive angle? The tactics of diving away is legit and works fine in certain situations, but it does not in others. Just saying that Spitfire is also a fast fighter plane and there are many factors to consider. There is not much you can do when you allow to get a Spitfire close on your six I am afraid.

hnbdgr
May-20-2014, 05:35
+1
Spits follows almost everytime when diving away with closed Radiators, full throttle and WEP.
Thought it was "the" escaping maneuver for 109s, 2 days ago a spit even closed the gap in a dive.

Maybe i am doing something wrong, just reporting my experience of the last sorties.

I always manage to escape this way in the 109. Either bunt your nose down if you're at high speed already (450kmh +) or roll over if you're around 350kmh or less and then floor it, change direction once or twice as you do that to avoid possible interception You have to be persistent and the trick is not to start climbing right after this, else the spit will cut the corner in the vertical plane and catch up.

@Robo

thanks Robo, do you happen to have a link among your subscriptions perhaps? I can never find the right topic through search on here...

92 Sqn. Philstyle (QJ-P)
May-20-2014, 05:44
+1
Spits follows almost everytime when diving away with closed Radiators, full throttle and WEP.
Thought it was "the" escaping maneuver for 109s, 2 days ago a spit even closed the gap in a dive.
Maybe i am doing something wrong, just reporting my experience of the last sorties.

Here's a tip: Don't bunt the nose too fast! Progressively/ Gently push the nose down.
Too many 109 pilots go for the fast "bunt".
The spitfire will recover quickly from a "bunt". However, it is the sustained negative G that is his problem.
You must encourage the spitfire to maintain the negative G for a couple of seconds. The longer he stays negative G, the better.

Jump in a spitfire. See how much nose-down is required to start the "spluttering".
Then go back to the 109 and try "as little as possible" nose-down, in order to keep the spitfire at that moment when his engine starts to cut.

JG4_sKylon
May-20-2014, 05:46
Hi Robo,

i never used track recording for normal sorties on ATAG, only screen capture videos.
As i said i can not provide exact infos so take my comment not as final statement, but as a feeling that there might be something wrong.


There is not much you can do when you allow to get a Spitfire close on your six I am afraid.

Well, that´s exactly my and other squadmates experience....

Edit: thanks hnbdgr and Phil for the advise, i will try to remember when i am going to Panic again next time because of a damn Spit on my 6 :stunned:

Vlerkies
May-20-2014, 05:48
So what exactly is wrong with that particular fight in the video? I would do exactly the same in his situation ans so would you. There is nothing that wasn't possible in real life as far I can see.
Hey, nothing wrong, if it works for you use it.

I would expect the engine to starve as a result of the neg G almost immediately, note I say expect! Likewise in the Neg G dive evasive, mommy I am a 109 and running home, maneuver :)

I havent tried it myself, but have seen vids of pilots on ACG. All that happens is the engine sound changes from a nice revving engine to a purr, with what appears to be no appreciable loss of speed by comparison to a 109 running its engine at balls to the wall.
We are talking 1940 right. Spit and Hurri pilots by all accounts did 'not' nose down hard, especially if in pursuit of an enemy, they rolled or half rolled because of the very issue with the fuel starvation. Not seeing that in Clod.
I can buy the maneuver like in my vid when the guys life depends on it as a last ditch attempt for sure but it would come at a cost.

Anyway, I am sure this has been debated before, so let me do some research and self education.

Vlerkies
May-20-2014, 05:52
Here's a tip: Don't bunt the nose too fast! Progressively/ Gently push the nose down.
Too many 109 pilots go for the fast "bunt".
The spitfire will recover quickly from a "bunt". However, it is the sustained negative G that is his problem.
You must encourage the spitfire to maintain the negative G for a couple of seconds. The longer he stays negative G, the better.

Jump in a spitfire. See how much nose-down is required to start the "spluttering".
Then go back to the 109 and try "as little as possible" nose-down, in order to keep the spitfire at that moment when his engine starts to cut.

Interesting, I am probably guilty of pushing to hard then.
Thanks

If I can get the pursuer to roll, it changes the ball game completely.

Robo.
May-20-2014, 06:55
thanks Robo, do you happen to have a link among your subscriptions perhaps? I can never find the right topic through search on here...

I am sorry I can't help you now (I tried including the relevant links already) as the 1c forum is blocked for me at work and so is the search page on this forum. I will add them later on for you :thumbsup:

I think it's generally a good idea to try all planes in the sim to see what they can and what they can not do. Philstyle's advice is spot on, once you know the limits, it's easier to shake off the RAF fighter on your 6. There is only one way of figuring it out - jump in the RAF planes and give them a spin. :salute: That might change your perception on what's going on. Same advice for any pilot flying the red only and 'complaining' about magic 109 abilities. :D

Osprey
May-20-2014, 10:57
+1
Spits follows almost everytime when diving away with closed Radiators, full throttle and WEP.
Thought it was "the" escaping maneuver for 109s, 2 days ago a spit even closed the gap in a dive.

Maybe i am doing something wrong, just reporting my experience of the last sorties.

I fly the Hurricane, but this is a sore point because from an equal position you won't catch the 109 in a Spitfire on the deck (E4), when in reality the Spitfire was 5mph faster @12lbs. You have a tiny lickle ickle bit of speed with closed rad but the engine will pop fast, oh yes it will. So you can eek out about the same speed with intense fiddling to follow but catch? No chance. If someone else can demo a race otherwise, good pilots mind you, then please, I'd like to see it. I've done this myself in a controlled test with Vranac, he flies both types very well indeed. The Spit you mention must've had energy on you or you are missing something here I'm afraid.

And yes it was an escape move for 109's. But remember that the RAF were under orders not to follow to France, it was tactical and typical, but plenty were caught after dives and shot down. Initial dive acceleration in the 109 is higher so it will pull away, but then the 109 pilot is standing on the rudder bar with a bit of force and the Spitfire can started to overtake (provided the dive goes under 10kft)

Regarding the inverted loop of the Hurricane which Vlerkies mentions. Pretty standard BOB was to tell pilots that in emergency to "park everything top left" (stick and rudder). The Hurricane would tip over in a complete inverted roll safe and sound which the 109 wouldn't not get a shot at, and funnily enough it does that in game too. I didn't watch the video. I disapprove of bunting, flight sims are in desperate need of pilot modelling because all that bunting would injure pilots and even kill aircrew, let alone looking about during a 5g roll or firing the gun or getting a bit of red for -3g when it risks haemorrhage.

hnbdgr
May-20-2014, 11:13
when in reality the Spitfire was 5mph faster @12lbs.

I'm sorry for OT, but: I've been looking into this for some time. It has been debated over and over and there is no conclusive evidence that would favour either aircraft. Plenty of threads about this both here and on banana forums.

In game a +12lbs boost 100oct spit will catch a 109-e1/3/4 with db601 if the latter doesn't engage its clockwork boost. With the boost the 109 is slightly faster for the 60 seconds (+however long it takes to shed that extra 15kmh after boost runs out).

92 Sqn. Philstyle (QJ-P)
May-20-2014, 11:18
This old documentary is quite nice;

https://www.youtube.com/watch?v=vDzZnCkbxgs
From 24:45 onwards for a few minutes.

Now, it seems to me that Bader and Stuck are describing a phenomena slightly different from what we get in game. The Merlin they describe does seem to be more affected than the version we have in game.

Now, do we believe these guys?
Note that, at 27:50, they start talking about the turning of the spit. In game, the 109 CAN pull lead on the spitfire at the start of the turn. However, Bader and Tuck suggest that the 109 could NOT get lead in a turn, and that turning was a pretty full-proof way of avoiding the attack .

So, in-game the merlin seems less affected by carbourettor starvation than these pilots suggest (?), however in-game the 109 can pull lead in a turn (momentarily)... when we fiddle around at the margins with these so-closely-matched aircraft this kind of see-saw is inevitable I think.

Now, there's one more reason why you don't see the half-roll all the time in cliffs. Listen carefully at 25:46 seconds. This is what most spitfire pilots do in the game. They just wait for the 109 to level out a bit (which the 109 has to do eventually or he will hit the ground). "cut the corner".

Even with the roll, Bader says that the RAF got very good at it, and they could "nip around" quite quickly, and the 109 was "still there" just a bit farther away.

ATAG_Snapper
May-20-2014, 11:42
This is an offshoot from the "Spitfires not catching fire" thread down in the Team Fusion section. Some excellent comments & opinions have been given re Spitfire/Hurricane carbs cutting out in neg g bunts, and the effects of pos/neg g's on aircrew looking around, shooting, and even surviving rinse & repeats of same. As a disclaimer, I have no idea what TF is/isn't doing in this regard for TF 5.0. Also, I'm not a Real Life pilot, much less a military pilot, so I can only relate what I've read or heard by those who are. ALL opinions are welcome here.

To get the ball rolling:

1) I find it a major immersion killer to be chasing a LW aircraft (including twin engine bombers) that "porpoise" to disrupt my firing solution. Bunting is fine and historically accurate. But repeatedly pushing -1 g's then immediately pulling +3 g's easily a dozen times in rapid succession during a chase defies credibility. I base this on comments made in Teamspeak by Real Life jet fighter pilots, plus I have never read of porpoising evasion tactics in actual RAF Battle of Britain AAR's. Bunting ONCE, yes. Successive porpoising, no. Yet this is a tactic commonly used by virtually all LW aircraft that I have witnessed personally countless times in this sim.

2) The superior blackout resistance by 109 pilots in their semi-reclining seating position over the inferior blackout resistance by Spit/Hurri pilots in their upright seated position. IMHO I believe this is far over modelled in 4.312 Cliffs of Dover. I have engaged 109's in exaggerated lag pursuits and still have blacked out only to have the 109 continue to maneuvre and shoot me down while I'm still blacked out. Again, speaking with Real Life jet fighter pilots on Teamspeak, the opinion I got was that in the pre-pressure suit era this advantage would be minimal at best. In their collective opinions a far more influential factor would be the relative physical conditioning of the pilots involved (physique, fatigue, experience, training, etc). I believe this disparity in blackout resistance as currently modelled in 4.312 Clod should be minimized or even dispensed with altogether.

What say ye? :-)

hnbdgr
May-20-2014, 12:01
2) The superior blackout resistance by 109 pilots in their semi-reclining seating position over the inferior blackout resistance by Spit/Hurri pilots in their upright seated position. IMHO I believe this is far over modelled in 4.312 Cliffs of Dover. I have engaged 109's in exaggerated lag pursuits and still have blacked out only to have the 109 continue to maneuvre and shoot me down while I'm still blacked out. Again, speaking with Real Life jet fighter pilots on Teamspeak, the opinion I got was that in the pre-pressure suit era this advantage would be minimal at best. In their collective opinions a far more influential factor would be the relative physical conditioning of the pilots involved (physique, fatigue, experience, training, etc). I believe this disparity in blackout resistance as currently modelled in 4.312 Clod should be minimized or even dispensed with altogether.


I can comment on this bit. The british trials of the captured 109 did make a special note of the fact that it did help the pilot with blackouts. So there will be and should be a difference in game as there was in real life. As to what degree? Maybe someone here will answer that? :)

EDIT: point 1 - bunting LW planes. Definitely not a viable thing to do for the bombers - crew would get their heads banged and stuff will start flying all over the place inside.... But there's nothing stopping a strapped in fighter pilot in doing repeated maneuvers like this as far as the airframe can take it surely..?

ATAG_Snapper
May-20-2014, 12:19
I can comment on this bit. The british trials of the captured 109 did make a special note of the fact that it did help the pilot with blackouts. So there will be and should be a difference in game as there was in real life. As to what degree? Maybe someone here will answer that? :)

Fair point. My question as to the degree of difference would be an interesting discussion.


EDIT: point 1 - bunting LW planes. Definitely not a viable thing to do for the bombers - crew would get their heads banged and stuff will start flying all over the place inside.... But there's nothing stopping a strapped in fighter pilot in doing repeated maneuvers like this as far as the airframe can take it surely..?

The fighter aircraft shouldn't have a problem but the human pilots would, according to the military pilots on Teamspeak. Apparently pushing negative g's is an unpleasant experience, then immediately pulling positive g's would be extremely taxing on the human frame. To do this in rapid succession, as done commonly in Clod, would, in their opinion, exceed human pilots' endurance by manyfold....much less still look around, maneuvre, aim, shoot, and other complex tasks.

EDIT: I'm being conservative on the g values given for sake of discussion. The carbs on the Spits and Hurries in Clod are set to cutout at the specification value of -0.9 g's. Since my Spit's Merlin cuts out when I try to follow the enemy aircraft's pushover, I'd say -1 g is the minimum that the LW pilot is experiencing.

hnbdgr
May-20-2014, 13:57
The fighter aircraft shouldn't have a problem but the human pilots would, according to the military pilots on Teamspeak. Apparently pushing negative g's is an unpleasant experience, then immediately pulling positive g's would be extremely taxing on the human frame. To do this in rapid succession, as done commonly in Clod, would, in their opinion, exceed human pilots' endurance by manyfold....much less still look around, maneuvre, aim, shoot, and other complex tasks.

EDIT: I'm being conservative on the g values given for sake of discussion. The carbs on the Spits and Hurries in Clod are set to cutout at the specification value of -0.9 g's. Since my Spit's Merlin cuts out when I try to follow the enemy aircraft's pushover, I'd say -1 g is the minimum that the LW pilot is experiencing.

According to my newlyfound knowledge(internet :)) you're quite possibly right. Apparently something like that would make the heart fail. The question is how fast are the pilots doing this (frequency of going + to - and back), how much negative g are they pushing and how much positive g are they pushing. Another thing to keep in mind is a jet pilot would also experience much stronger forces on his body doing this sort of thing. Is there a G value readout hidden in the TF device link interface? If so we could try and prove this shouldn't be happening.

RAF74_Buzzsaw
May-20-2014, 15:23
There is not much you can do when you allow to get a Spitfire close on your six I am afraid.

Not the case.

I don't fly the 109 as my main ride, (Hurricane pilot), but I find I can out scissor either a Spitfire or Hurricane quite easily and force an overshoot.

The key is using the superior rollrate of the aircraft, combined with cutting throttle at the appropriate moment.

Once you force the overshoot, then you make your escape by split S'ing and diving away in the opposite direction.

109's should always try to keep at least 3000 meters under them to allow them to reach maximum dive speed of 750 kmh... which exceeds the Spitfire or Hurricane max dive speed... if they try to follow they start to lose parts. But remember, if your nose is pointed down vertically and you are travelling at 700 kmh, you won't recover. As your aircraft exceeds 700 kmh, you should be in no more than a 45 degree dive and beginning to recover... also you don't really want to touch 750 kmh, too easy to exceed the limit and lose parts.

If you are caught low and slow on the deck, then you have a much bigger problem... you can scissor with the Spits and Hurris for quite a while, but unless you have a friend nearby to bail you out, you can't run away from them, especially the Spitfires. :salute:

Robo.
May-20-2014, 15:54
Not the case.

I don't fly the 109 as my main ride, (Hurricane pilot), but I find I can out scissor either a Spitfire or Hurricane quite easily and force an overshoot.

What I meant is there is not much you can do, not nothing you can do and it was reflecting the pure ability to extend horizontally. :D You're absolutely right of course, I never scissor vs. a 109 and when I am on a six of one, I will counter his scissors by a high yo or or other vertical maneuver to stay behind him as I recon that challenging any 109 pilot in scissors would be a big mistake due to roll rate and armament. I'd say though you would still have difficulty to get rid of an experienced pilot on your 6, scissors could win you some time. I replied to similar thread about scissors specifically saying the same thing like you though including cutting the throttle bit. :thumbsup:

btw has this thread been moved or renamed?

ATAG_Snapper
May-20-2014, 16:00
What I meant is there is not much you can do, not nothing you can do. :D You're absolutely right of course, I never scissor vs. a 109 and when I am on a six of one, I will counter his scissors by a high yo or or other vertical maneuver to stay behind him as I recon that challenging any 109 pilot in scissors would be a big mistake due to roll rate and armament. I'd say though you would still have difficulty to get rid of an experienced pilot on your 6, scissors could win you some time. I replied to similar thread about scissors specifically saying the same thing like you though including cutting the throttle bit. :thumbsup:

btw has this thread been moved or renamed?

Re thread moved: Actually I started this new thread and moved the non-Spitfire on Fire posts over here. Both topics are excellent (Spits on Fire, G Effects on aircraft/aircrew) and deserved their own threads.

ATAG_EvangelusE
May-20-2014, 19:15
I'm with Snapper regards the difference in G modelling blackout effect on Pilots.

In all the books I have read, interviews and documentaries with surviving BoB pilots ( Axis and Allied) I have heard much about the various advantages and disadvantages between the Spit and 109 but not once can I recall reading or hearing a pilot mention that one had a significant advantage or disadvantage over the other regards G effects.

The difference is significant in game at the moment. If anyone has any source documentation in the form of testimony from actual pilots who flew these ac then please post it.

RAF74_Buzzsaw
May-21-2014, 02:09
I'm with Snapper regards the difference in G modelling blackout effect on Pilots.

In all the books I have read, interviews and documentaries with surviving BoB pilots ( Axis and Allied) I have heard much about the various advantages and disadvantages between the Spit and 109 but not once can I recall reading or hearing a pilot mention that one had a significant advantage or disadvantage over the other regards G effects.

The difference is significant in game at the moment. If anyone has any source documentation in the form of testimony from actual pilots who flew these ac then please post it.

British Test report, comparison between Hurricane and 109E.

On second page, note the reference to the Hurricane pilot tending to black out earlier when pulling out of a high speed dive:

http://www.wwiiaircraftperformance.org/hurricane/hurricane-109.pdf

The Spitfire's seating position was very similar to the Hurricane's.

Later in the battle, some RAF Squadrons fitted rudder pedals which had two foot positions, one for normal flight, and a higher one for hi G maneuvers. By placing their feet on the higher mounted pedals, pilots could improve their G loading tolerance.

Vlerkies
May-21-2014, 05:31
This old documentary is quite nice;

Watched that last night Phil and thoroughly enjoyed it. Thanks :thumbsup:

How about that old duck (probably a belter back in the day) that went for a flip on a Spitty hanging on the tail, haha. :salute:

Your comment about the fiddling with these 2 very evenly matched aircraft hits the nail on the head, I agree entirely. Its not so much of a balancing act as it is a finessing one or fine tuning one, thats under some critical scrutiny constantly.
TF do an amazing job and although that goes without saying, it should be noted from time to time. Noted ;)

On the Neg G dive in the vid. The aces cover it all and what a pleasure to see them chatting like that.
The point is in Cliffs the planes are following us down carrying the Neg G. If the Neg G effects on the carb are correct they should not be able to do this and maintain the gap, they would have to roll or stay up.
If they stayed up, or descended more gradually to avoid fuel starvation, then waited for the 109 to climb to cut the corner again that's fine.

So I am not in the fastest 109 (E1) but my acceleration in the dive, combined with the Neg G should allow me to pull some distance. Its not an indefinite life saver, its a means to escape, albeit temporarily.
If the Spit comes down slower and aims to cut the corner he has lost his alt and is at risk of getting hammered by other 109's.
Also, if he rolls a 109 pilot has a better chance to roll out the other way using his superior roll rate. This would happen at the top of the dive before control surface compression so if the 109 pilot is alert he can use that to his advantage.

I take your point and advice on a more progressive neg g down rather than a hard forward as you say it will be more effective, but this seems contrary to the account given in the video by DB. They talk hard forward.

On pulling lead in the 109, it was always massively difficult and left you in a precarious position with no energy if you did not disable your target. You can do it effectively once with and with killing the throttle a to decelerate in the turn and power up before the apex of the target and before your slats deploy. You need to be certain of the shot though.
In the last patch it became a fraction easier, not much but enough to notice, as the leading edge slats deploy a degree or 2 later than before. This allows you to pull that tight turn for a bit without running the risk of stalling the wing and deploying the slats which then bleeds all your energy.
1 thing I have always tried to do in the 109 is fly it without those things coming out as much as my limited skill allows, they eat E like a cancer so it pays to fly smooth in this bird.

hnbdgr
May-21-2014, 06:41
Watched that last night Phil and thoroughly enjoyed it. Thanks :thumbsup:

How about that old duck (probably a belter back in the day) that went for a flip on a Spitty hanging on the tail, haha. :salute:

Your comment about the fiddling with these 2 very evenly matched aircraft hits the nail on the head, I agree entirely. Its not so much of a balancing act as it is a finessing one or fine tuning one, thats under some critical scrutiny constantly.
TF do an amazing job and although that goes without saying, it should be noted from time to time. Noted ;)

On the Neg G dive in the vid. The aces cover it all and what a pleasure to see them chatting like that.
The point is in Cliffs the planes are following us down carrying the Neg G. If the Neg G effects on the carb are correct they should not be able to do this and maintain the gap, they would have to roll or stay up.
If they stayed up, or descended more gradually to avoid fuel starvation, then waited for the 109 to climb to cut the corner again that's fine.

So I am not in the fastest 109 (E1) but my acceleration in the dive, combined with the Neg G should allow me to pull some distance. Its not an indefinite life saver, its a means to escape, albeit temporarily.
If the Spit comes down slower and aims to cut the corner he has lost his alt and is at risk of getting hammered by other 109's.
Also, if he rolls a 109 pilot has a better chance to roll out the other way using his superior roll rate. This would happen at the top of the dive before control surface compression so if the 109 pilot is alert he can use that to his advantage.

I take your point and advice on a more progressive neg g down rather than a hard forward as you say it will be more effective, but this seems contrary to the account given in the video by DB. They talk hard forward.

On pulling lead in the 109, it was always massively difficult and left you in a precarious position with no energy if you did not disable your target. You can do it effectively once with and with killing the throttle a to decelerate in the turn and power up before the apex of the target and before your slats deploy. You need to be certain of the shot though.
In the last patch it became a fraction easier, not much but enough to notice, as the leading edge slats deploy a degree or 2 later than before. This allows you to pull that tight turn for a bit without running the risk of stalling the wing and deploying the slats which then bleeds all your energy.
1 thing I have always tried to do in the 109 is fly it without those things coming out as much as my limited skill allows, they eat E like a cancer so it pays to fly smooth in this bird.

Quick question regarding the slats - did they deploy based on the stick input - e.g. pull the stick back and they will shoot out when stick passes a threshold and more importantly - do they get activated by using only trim... or does tail heavy trim make them shoot out faster?

JG4_Widukind
May-21-2014, 07:05
I hope TF will stay neutral.
But iam stay with Skylon the Spit have to much konstant Power in turns.
A Examble they can turn a 360 turn and climb 1000m up.I try to say,they losing not enogth speed,or have to much konstant speed in turns.

Vlerkies
May-21-2014, 07:12
Quick question regarding the slats - did they deploy based on the stick input - e.g. pull the stick back and they will shoot out when stick passes a threshold and more importantly - do they get activated by using only trim... or does tail heavy trim make them shoot out faster?
They deploy automatically as a result of pressure in an attempt to stop the wing from stalling in high AoA situations. I will surely provide the wrong explanation for lack of the correct terminology, but have a look here for a detailed brief.

http://109lair.hobbyvista.com/techref/systems/control/slats/slats.htm


So if you do pull very tight turns and your speed bleeds off you will see them deploy, just fly around a bit and test, you can actually feel/hear them as well.
When in a fight always try and fly keeping your energy up and avoid the heavy turns. It will keep you faster and give you more options.

ATAG_EvangelusE
May-21-2014, 07:18
British Test report, comparison between Hurricane and 109E.

On second page, note the reference to the Hurricane pilot tending to black out earlier when pulling out of a high speed dive:

http://www.wwiiaircraftperformance.org/hurricane/hurricane-109.pdf

The Spitfire's seating position was very similar to the Hurricane's.

Later in the battle, some RAF Squadrons fitted rudder pedals which had two foot positions, one for normal flight, and a higher one for hi G maneuvers. By placing their feet on the higher mounted pedals, pilots could improve their G loading tolerance.


Thanks Buzzsaw, what is difficut to assess is the margin of difference. I still don't quite get why BoB pilots did not talk about this as a significant difference but I did a quick search on 'two step rudder modification to Spitfire' and early google results suggest that all front line units were retro fitted with the modified rudder pedal by the Summer of 1940.

From what you say,I would expect the Spit Mk2 to have different G effect pilot blackout modelling as it would have been fitted with two step rudder pedals.

hnbdgr
May-21-2014, 07:18
They deploy automatically as a result of pressure in an attempt to stop the wing from stalling in high AoA situations. I will surely provide the wrong explanation for lack of the correct terminology, but have a look here for a detailed brief.

http://109lair.hobbyvista.com/techref/systems/control/slats/slats.htm


So if you do pull very tight turns and your speed bleeds off you will see them deploy, just fly around a bit and test, you can actually feel/hear them as well.
When in a fight always try and fly keeping your energy up and avoid the heavy turns. It will keep you faster and give you more options.

Ha, thanks I googled that website after I asked the question:) I knew what the slats were for, but not sure how they were triggered. If they are trigerred as a result of AoA, there must be some way for them to know the aircraft is experiencing AoA. Ergo the stick..? If they are not in any way connected to the trim however, I should be able to trim the aircraft into a turn and not have them deploy...? Anyway I will test this tonight.

Vlerkies
May-21-2014, 07:29
Ha, thanks I googled that website after I asked the question:) I knew what the slats were for, but not sure how they were triggered. If they are trigerred as a result of AoA, there must be some way for them to know the aircraft is experiencing AoA. Ergo the stick..? If they are not in any way connected to the trim however, I should be able to trim the aircraft into a turn and not have them deploy...? Anyway I will test this tonight.

Air pressure, not physical control input from you.

You misunderstand a bit, they deploy as a result of air pressure changes. Your flight controls may cause this pressure change on the wing due to your current flight path but they do not actually control the slats at all.


slat design was first proposed by Sir Frederick Handley Page around 1919 as a way to maintain airfoil efficiency at high angles of attack. As the airfoil pivots at a greater angle from the direction of airflow, the point at which the flow detaches from the upper wing surface moves further and further forward. Eventually, if this condition continues, the airflow "unsticks" completely from the upper surface, and the wing stalls. In order to delay this action, the slat on the 109 extends outwards under aerodynamic pressure, channeling airflow back up and over the wing upper surface, thereby maintaining airfoil effectiveness. The following diagram may help illustrate the airflow characteristics mentioned above:

hnbdgr
May-21-2014, 07:31
Air pressure, not physical control input from you.

You misunderstand a bit, they deploy as a result of air pressure changes. Your flight controls may cause this but they do not actually control the slats at all.

That explains it. thank you!

Osprey
May-21-2014, 07:36
This is an offshoot from the "Spitfires not catching fire" thread down in the Team Fusion section. Some excellent comments & opinions have been given re Spitfire/Hurricane carbs cutting out in neg g bunts, and the effects of pos/neg g's on aircrew looking around, shooting, and even surviving rinse & repeats of same. As a disclaimer, I have no idea what TF is/isn't doing in this regard for TF 5.0. Also, I'm not a Real Life pilot, much less a military pilot, so I can only relate what I've read or heard by those who are. ALL opinions are welcome here.

To get the ball rolling:

1) I find it a major immersion killer to be chasing a LW aircraft (including twin engine bombers) that "porpoise" to disrupt my firing solution. Bunting is fine and historically accurate. But repeatedly pushing -1 g's then immediately pulling +3 g's easily a dozen times in rapid succession during a chase defies credibility. I base this on comments made in Teamspeak by Real Life jet fighter pilots, plus I have never read of porpoising evasion tactics in actual RAF Battle of Britain AAR's. Bunting ONCE, yes. Successive porpoising, no. Yet this is a tactic commonly used by virtually all LW aircraft that I have witnessed personally countless times in this sim.




This to me is the next stage in flight simming. I started a thread on it on BOS a while back, they didn't comment, go find it and have a read because there was a lot of great feedback.

Essentially there were a few parts to it
1. What you mention Snapper, the ridiculous bunting. The thread revealed that it's just not something you can get away with in real life. Massive blood pressure in the head then low pressure, then high again - it would just kill you. I've never seen any gun cam footage where pilots evade like this either, if there is some, please show me.
2. Looking about under high G. I don't know how many people have pulled G in combat turns in real life but one thing I didn't find possible was looking about like I was straight and level whilst doing it. It takes physical effort and the vision blurs, greys and tunnels a bit.
3. Fitness. I would like to see pilots get worn out on a flight. A simple system could be modelled as a start, the same as in FIFA 14 where the player has a stamina bar. Make him sprint everywhere and he starts to slow up.
4. Injury on ditching. Brian Kingcombe comments on how dangerous it was to ditch in the water because you hit a wave and stop instantly, get knocked out and sink with the aeroplane. It was better to bail out over the sea. On land most pilots got a smack in the face with the gunsight at least, the Hurricane more forgiving because of the radiator position.

Regarding top speeds, can TF post the charts used for Spitfire and E4 please?

Robo.
May-21-2014, 08:09
The point is in Cliffs the planes are following us down carrying the Neg G. If the Neg G effects on the carb are correct they should not be able to do this and maintain the gap, they would have to roll or stay up.

If you follow the 109 into an aggressive negative G evasive maneuver, your Merlin engine will not like the situation at all, you will loose RPM and speed and you will not maintain the gap. The disadvantage is also very noticeable in a vertical stall fight. Feel free to try it out and you will see yourself. :thumbsup:

These are the threads I could not find and link yesterday:

http://theairtacticalassaultgroup.com/forum/showthread.php?t=4581

http://theairtacticalassaultgroup.com/forum/showthread.php?t=9779

You might remember that this Merlin feature has been changed quite a few times in the previous patches (pre-TF), and discussed in length on 1c forums, focus on posts from IvanK:

http://forum.1cpublishing.eu/showthread.php?t=20462

http://forum.1cpublishing.eu/showthread.php?t=25910

The overdone effect in one of the ancient vanilla versions has been fixed to what is believed to be historically correct value as per the documents posted in the discussion.

Vlerkies
May-21-2014, 08:46
The overdone effect in one of the ancient vanilla versions has been fixed to what is believed to be historically correct value as per the documents posted in the discussion.

Thanks bud, lots of reading but clear it has been discussed in depth and changed a few times, but not since TF got involved.

As for being historically correct as per docs posted and stuff, I can't dispute that cause I really do not know enough about it.
What I can say is that when I get directly followed to the deck after a neg g push forward I would be more comfortable seeing the RAF fighter pilot in hot pursuit rolling to follow, also historically correct you would agree, and not just pointing his nose down.

Robo.
May-21-2014, 09:22
What I can say is that when I get directly followed to the deck after a neg g push forward I would be more comfortable seeing the RAF fighter pilot in hot pursuit rolling to follow, also historically correct you would agree, and not just pointing his nose down.

I completely understand - but how exactly would you like to achieve this? If we assume that the Merlin reaction regarding the amount of neg-G and the cutout effect itself are modeled correctly... It's the same like with the early RAF formations that were very ineffective and vulnerable (Idiotenreihen, tight vic-formations or tail-end-charlie practice...) but also very much historical. Now try persuading online players flying like that instead of in pairs etc. You see all planes in this sim doing maneuvers that would probably make your eyes pop but it's the lack of roll over maneuver on your six that is bothering you.

It takes some practice (and skill perhaps) to work around this limitation. If you're careful, you can stay within the -0.9 G threshold and push your nose down gently.

The debate about pilot stamina etc. is also very interesting, but honestly I can't see how it can be brought into any flight sim realistically.


Thanks bud, lots of reading but clear it has been discussed in depth and changed a few times, but not since TF got involved.

edit - also on this, IvanK has been involved with this sim with 1c (he did lots of research for the original dev team) as well as with TF later on. The documents leading to fixing the issue were also provided by him IIRC. He's an excellent blue pilot and one of the most knowledgeable guys I've met on the sim forums - just for the record.

Vlerkies
May-21-2014, 09:48
Its the assume bit that leaves room for debate ;)

edit: let me attempt to qualify that, if we assume it is correctly modeled, the Neg G effect on the Merlin, conversely then Baders and Stucks accounts of it all are nonsense.

Robo.
May-21-2014, 10:10
Its the assume bit that leaves room for debate ;)

OK. Feel free to debate it then. Again :) You have got all relevant documents posted already, it's been debated to depth, I find the topic very interesting but have nothing to add, really.

Have you actually tested it other than from the 109 cockpit? :D

Vlerkies
May-21-2014, 10:12
Nope I haven't tested it in a Spit, I don't even know how to turn on a Spit. :)

Sorry I edited my other post, but again let me attempt to qualify that, if we assume it is correctly modeled, the Neg G effect on the Merlin, conversely then Baders and Stucks accounts of it all are nonsense.

92 Sqn. Philstyle (QJ-P)
May-21-2014, 10:39
Sorry I edited my other post, but again let me attempt to qualify that, if we assume it is correctly modeled, the Neg G effect on the Merlin, conversely then Baders and Stucks accounts of it all are nonsense.

Even if Tuck/Bader didn;t accurately describe the situation I wouldn't go so far as to call it "all nonsense". But it certainly does tend to point in a direction, perhaps divergent from what people are claiming is the situation in-game.

Surely two intelligent pilots can line-up, side by side, and conduct such a dive and record the track?

Robo.
May-21-2014, 10:55
Nope I haven't tested it in a Spit, I don't even know how to turn on a Spit. :)

Sorry I edited my other post, but again let me attempt to qualify that, if we assume it is correctly modeled, the Neg G effect on the Merlin, conversely then Baders and Stucks accounts of it all are nonsense.

Not nonsense, but with all due respect, I have more confidence in the G-meter installed by RAE than to any pilot account.

Everything has been covered in the threads I linked before, feel free to read it and re-test it all if you're interested. You don't even need to know the startup procedures, just pick any RAF fighter plane in free flight quick mission and push the stick in the direction away from you and watch what happens. :D

92 Sqn. Philstyle (QJ-P)
May-21-2014, 11:13
OK, here's what Vlerkies is getting at, I think.
The Spitfire cut-out seems to be OK, however, we don't see the appreciable LOSS in airspeed associated with the carb-failure that one would expect, if the cut-out really was a problem that needed solving. (and that matches the pilot's descriptions)

NONE of the below is posted in my capacity as a TF member, any issues arising are not the opinion of TF, just me!

I've just had a wee look, and from 250mph (spit) or 400kph (109), I can push the nose pretty steeply into a rapid dive of around 80 degrees nose-down.

The spitfire ASI will drop from 250mph to 220mph before I hit the dive angle and reduce the negative G. at that point the ASI climbs back up.
The 109 ASI will drop from 400kph to 350kph in approximately the same maneuver, then it starts to accelerate as the bunting stops, at the same time as the spit is recovering too.

So, whilst the Spitfire loses 12% of its airspeed in the "bunt", the 109 ALSO loses 12%.

In that respect, the "loss" of power does not currently appear to translate into any obvious loss of airspeed for the spitfire above the 109.
To my mind, this does appear to warrant further investigation.

Talisman
May-21-2014, 11:24
I suggest you jump in a Spitfire or a Hurricane and try following a 109 that evades in neg-G and you will see yourself. :thumbsup: If you see the RAF guy behind you climbing as you dive, then watch out, he probably knows what he's doing.

hnbdgr - if you're interested in the topic, it's been discussed in depth in here as well as on 1c forums a while ago.

True. The cut-out is very noticeable to me, particularly after I have been flying a CloD Bf 109 for a while, or BoS, and then I go back to the CloD Spit. Its one of the reasons I don't fly the 109 that often, because I can lose my edge when it comes to going back to the Spit. You can't just put the stick forward and expect the Spit or Hurry engine to keep beating. After a while you get so good at compensating for the cut-out that you do it as part of your flying instinctively and then I find I can almost, but not quite, forget about it. The thing is, I think I have it all under control and then in the heat of combat it can still catch me out. The most worrying time is when I have a 109 too close for comfort and I am trying to dive away. Often the engine will cut out for what seems an age when you have a 109 on your tail. At high speed in a slight dive I even get problems with cut-out if I tap in just a little bit of trim. So, sometimes just trimming a little will cause extended coughing of the engine of at high speed at certain angles of flight. Also, for some reason I find the Hurry easier to manage in this regard; perhaps because it is a bit more stable than the Spit. In real life, the cut-out did not stop the Spit and Hurry shooting down lots of Bf 109 and catching them in a dive.

As for following the 109 in a sudden dive, well I either climb up to the side first and then wing over or keep going level but turn to the side to try and keep him in view before deciding whether to follow with a wing-over or break off. Sometimes it is like the 109 just expects to get away by just bunting into a dive and you can give him a surprise by winging over and following him, it is very quick to do. I also close my radiators and drop the prop pitch down; the Spit 1a 100 with BCO on is very fast! The bunt dive is not a 'golden solution' for a 109 as their is no such thing as a safe bet if a Spit is close enough. Remember that on ATAG we mostly fly in clear blue sky with very good visibility and it is very easy flying a PC. Also, diving after aircraft on servers with icons is a lot easier. I find diving after the enemy in BoS a lot harder all together, as there is a lot of weather and poor visibility to put up with. In real life, visibility could be easily lost on a diving 109 and there was a risk in diving that we do not have to bother with. Also, we are not putting up with the physical demands of it.

Bottom line is, if you are in a Bf 109, don't just expect to get away with a dive or out-climb your enemy just because you are in a 109. Same for Spit pilots, just don't expect to out-turn a 109 because you are in a Spit. Good pilots know there is more to it than that.

Happy landings,

Talisman

Robo.
May-21-2014, 11:51
In that respect, the "loss" of power does not currently appear to translate into any obvious loss of airspeed for the spitfire above the 109.
To my mind, this does appear to warrant further investigation.

Definitely worth testing Philstyle :thumbsup:

In my online experience, you feel every mistake speed-wise, if you happen to push that bit too much, and your engine misses a second or so. The a/c you followed starts to extend rapidly..

Vlerkies
May-21-2014, 12:03
OK, here's what Vlerkies is getting at, I think.

Thank you, may your children be blessed with wealthy parents :salute:

As I am no Spit or Hurri pilot I have seen many vids where neg g impacts on the engine 'sound' of the RAF fighters, I stated that previously.
I am questioning the price that is paid in airspeed/energy when doing that!!!! It must be something, some value against a fuel injected DB601 going hell for leather.
As the 2 RAF aces put it, if it was bad enough for them to be forced to do a half roll to follow, it must have been an 'appreciable sacrifice', or else they just would have pushed nose down as well.

Factor in the 109 being an energy fighter with fast acceleration in the dive + higher dive speed + the trade off the RAF fighter has to make going nose down, it is understandable Luftwaffe pilots were instructed to use this as a first line of defence when jumped and a fair distance should be obtained depending on your alt and how long you can hold your max dive speed.

The same theory can be applied to the neg g push down and then pull up being used by the RAF as an evasive maneuver.
Perhaps more detailed testing will reveal their is indeed a sacrifice, then all this is moot, but speaking from a position of being chased a lot :D, diving like this often has the guys just following me down, they only break off when I start to exceed 650km+.

Anyway, I will look into it a bit more just to satisfy my own curiosity, one way or the other.

edit: it gets me back to the point where I say I do not see the guys doing the half roll to follow, so am (perhaps incorrectly) assuming (that word again) that the trade off going nose down is not substantive enough in Cliffs to force that historic maneuver.

RAF74_Buzzsaw
May-21-2014, 13:55
The Negative G carburetion effect in the game was examined carefully by TF prior to TF 3.0 and discussed at length by the FM team.

The decision was to leave it as it is, we believe it is modeled correctly. No changes are planned. :salute:

Vlerkies
May-21-2014, 14:05
mutter mutter, ok then :salute:

:)

Steve D
May-21-2014, 16:13
Factor in the 109 being an energy fighter with fast acceleration in the dive + higher dive speed + the trade off the RAF fighter has to make going nose down, it is understandable Luftwaffe pilots were instructed to use this as a first line of defence when jumped and a fair distance should be obtained depending on your alt and how long you can hold your max dive speed.

The same theory can be applied to the neg g push down and then pull up being used by the RAF as an evasive maneuver.
Perhaps more detailed testing will reveal their is indeed a sacrifice, then all this is moot, but speaking from a position of being chased a lot :D, diving like this often has the guys just following me down, they only break off when I start to exceed 650km+.

Anyway, I will look into it a bit more just to satisfy my own curiosity, one way or the other.

edit: it gets me back to the point where I say I do not see the guys doing the half roll to follow, so am (perhaps incorrectly) assuming (that word again) that the trade off going nose down is not substantive enough in Cliffs to force that historic maneuver.

The issue appears to be whether or not the Allied aircraft bleed enough speed as a result of an engine cut..I don't know whether it's modelled right or not, but if one aircraft wasn't going to bleed much speed, it's the Spitfire being a low drag airframe in particular the wings. Try and land one without flaps, it just doesn't want to slow down.

Also, somewhere along the line it's become accepted the 109 could dive faster than the Spitfire. As I understood it, the 109 accelerated into it's dive faster, yes, and was able to open up an initial lead, but as speed built up, the Spitfire would catch it. What was the Vne for the Emil? For the production Spitfires it was 470mph - 753kph. The Spitfire wing performed very well at high speed with its very low drag coefficient. Plus, at high speed, heavy ailerons AND elevators AND no rudder trim on a 109 make pulling out of a high speed dive a demanding process. There are plenty of contemporary accounts of 109's being caught in extended dives. The RAE report on the 109E they tested also said the Spitfire had no trouble staying with the 109 in a dive. How is it modelled here, again, I don't know.

As to the physical forces on the pilot during manoeuvers, it's tiring enough pulling simple steep turns, just to just keep your head level while while your vision pulls in and starts to grey out That was about 5G. There's no way I'd want to take anything like that as negative G As to yo-yoing between positive and negative g - forget that, you'll burst your eyes! Obviously difficult to model though! ;) Still, with aircraft basically evenly matched, it's a difficult job to pick it all apart. Change one thing here, and it upsets something there.....TF have a tough job!

Cheers!

RAF74_Buzzsaw
May-21-2014, 16:42
Believe it or not, the acceleration into a dive was an issue which TF looked at very closely and made a number of changes to increase realism.

For example, the 109's in vanilla were unable to 'bunt' or push their noses down quickly into a dive properly... what happened was an almost negative G stall... the aircraft became unstable, and uncontrollable for up to 3 seconds... greatly impairing the ability of the players to use this tactic.

We revised the behaviour of the aircraft completely for TF 4.312, now a virtual pilot can push his nose down and see a normal level of stability.

Re. acceleration in a dive... this has been much discussed in TF, (and in the past with IL-2 1946) but the facts are, even with an aircraft such as a P-47 vs a 109, acceleration during the course of a dive is not that significant. Typically no much more than a gain of 100 meters. Initial acceleration up to the normal level max. speed for the altitude is basically the same as level flight acceleration.

More significant to one aircraft being able to either escape or overtake during a dive is the maximum allowable dive speed. In the case of the 109E vs the Spitfire, the 109's have a max. allowable of 750 kmh vs 721 kmh for the Spitfire... the Hurricane is even further behind.

By the way... you can exceed the max. allowable speed... it's not a hard limit... BUT only if you are lucky, escape with no negative effects... however there is also an (increasing) chance you will suffer damage the more over the limit you take the aircraft. It's random... so one time you might be lucky... the next you won't. :salute:

Steve D
May-21-2014, 16:57
Nope I haven't tested it in a Spit, I don't even know how to turn on a Spit. :)

Dear boy, why didn't you say? I'll show you the taps on the Spitfire.

Set prop pitch to fully fine (lever to right of throttle all the way forward)
Fuel cock to on position (lever just to right and behind control column)
Throttle opened slightly for faster warm up, can be left in fully closed position though.
Chocks in, sometimes she starts to move slowly especially with throttle opened a bit, this will sort it out.
Mixture Rich
Both Magnetos on - two switches left side of instrument panel, below O2 gauge.
Coolant Rad fully open
Hit 'I' - or toggle selected engine, or whatever you hit to start the 109..it'll be the same.
Then, do nothing except maybe taxi on a very low throttle setting until your oil temp climbs to 40deg.

Off you go. Full power, left rudder to taste (I think..hard to visualise sitting here) to keep it straight, let the tail wheel come up at 60mph - lift off at 90-100mph. Some people apply right rudder trim to help, and a bit of elevator down trim. Up to you. Knock it off when airborne. Wheels up asap, once you've got say 160mph, coarsen the prop pitch to 2700-2800rpm (75% pitch is 2700rpm) and for max continuous power pull back the throttle to +3lb boost. (Historical).

To get back down, flaps and gear down at less than 140 mph, aim to cross the runway threshold at about 100mph or a little less, much higher speed than that and you might run out of runway - she likes to float. Chop throttle when appropriate and keep a slightly nose up attitude and it will stall at about 80mph onto the runway. If you keep the bottom edge of the armoured glass on the horizon near touchdown, that'll be about right for a 3-point landing.

Cheers!

Steve D
May-21-2014, 17:18
Believe it or not, the acceleration into a dive was an issue which TF looked at very closely and made a number of changes to increase realism.

For example, the 109's in vanilla were unable to 'bunt' or push their noses down quickly into a dive properly... what happened was an almost negative G stall... the aircraft became unstable, and uncontrollable for up to 3 seconds... greatly impairing the ability of the players to use this tactic.

We revised the behaviour of the aircraft completely for TF 4.312, now a virtual pilot can push his nose down and see a normal level of stability.

Re. acceleration in a dive... this has been much discussed in TF, (and in the past with IL-2 1946) but the facts are, even with an aircraft such as a P-47 vs a 109, acceleration during the course of a dive is not that significant. Typically no much more than a gain of 100 meters. Initial acceleration up to the normal level max. speed for the altitude is basically the same as level flight acceleration.

More significant to one aircraft being able to either escape or overtake during a dive is the maximum allowable dive speed. In the case of the 109E vs the Spitfire, the 109's have a max. allowable of 750 kmh vs 721 kmh for the Spitfire... the Hurricane is even further behind.

By the way... you can exceed the max. allowable speed... it's not a hard limit... BUT only if you are lucky, escape with no negative effects... however there is also an (increasing) chance you will suffer damage the more over the limit you take the aircraft. It's random... so one time you might be lucky... the next you won't. :salute:

It's good that the bunt fault was fixed. Realism is paramount in a sim like this. Given that, it raises a question though. What's the reasoning behind the 721kph Vne on the Spitfire when it's clearly documented at 470mph -753kph? Just asking, in the interests of historical accuracy. And yes you're right, they were often dived faster than that. Later dive speed trials achieved close to mach 0.9 in a Spitfire mk9 (Still with the same Vne of 470mph as a production Mk1) when investigating compressibility effects on wings. Even the pilots handbook gave a Vne corresponding to 0.85mach at the heights quoted, for a fully equipped service fighter.

Cheers!

RAF74_Buzzsaw
May-21-2014, 17:42
It's good that the bunt fault was fixed. Realism is paramount in a sim like this. Given that, it raises a question though. What's the reasoning behind the 721kph Vne on the Spitfire when it's clearly documented at 470mph -753kph? Just asking, in the interests of historical accuracy. And yes you're right, they were often dived faster than that. Later dive speed trials achieved close to mach 0.9 in a Spitfire mk9 (Still with the same Vne of 470mph as a production Mk1) when investigating compressibility effects on wings. Even the pilots handbook gave a Vne corresponding to 0.85mach at the heights quoted, for a fully equipped service fighter.

Cheers!

We are going by the Spitfire I pilot handbook. Which states 450 mph. Later models had different limits.

Everyone knows about the Spitfire's which were dived to mach .9... however the Spit IX had a different and reinforced wing. AND that Spitfire suffered damage in the dive.

No doubt you can point to many tests of Spitfires being dived to speeds in excess of the limit... there are also many Luftwaffe tests showing their aircraft also diving past their recommended limits.

We are modeling the aircraft based on what the official recommendations are, not on what might, maybe or perhaps might happen.

And in any case, as I have said... the limit in the game is not a hard line... you can exceed it... at your own risk... So at which point do parts start to be lost?... it depends... in fact you can exceed the limit and not suffer any damage... or exceed the limit and not suffer any visible damage... or exceed the limit and suffer damage.

We have made our decisions based on averages and expected results, not on optimum or hoped for results.

Don't like it...? We're sorry to hear that, but decisions have to be made, we've made ours. :salute:

Steve D
May-21-2014, 20:35
We are going by the Spitfire I pilot handbook. Which states 450 mph. Later models had different limits.

Everyone knows about the Spitfire's which were dived to mach .9... however the Spit IX had a different and reinforced wing. AND that Spitfire suffered damage in the dive.

No doubt you can point to many tests of Spitfires being dived to speeds in excess of the limit... there are also many Luftwaffe tests showing their aircraft also diving past their recommended limits.

We are modeling the aircraft based on what the official recommendations are, not on what might, maybe or perhaps might happen.

And in any case, as I have said... the limit in the game is not a hard line... you can exceed it... at your own risk... So at which point do parts start to be lost?... it depends... in fact you can exceed the limit and not suffer any damage... or exceed the limit and not suffer any visible damage... or exceed the limit and suffer damage.

We have made our decisions based on averages and expected results, not on optimum or hoped for results.

Don't like it...? We're sorry to hear that, but decisions have to be made, we've made ours. :salute:

Buzzsaw, Don't get me wrong here..I'm not unhappy in any way with the way things are in the sim. It's great. Also I'm not on about absolute speeds achievable under these or those experimental conditions. I was merely enquiring after the origin of the Vne (maximum permissible speed) figure for the Spit. The approved and tested Vne for Mk1 and Mk II Spits was 470mph IAS. The production Mk1 wings were stiffened to accept that speed over the original 380mph IAS specified for the prototype K5054. All production model dive testing was done to the higher speed and it's a well documented figure so I was curious, that's all. The Pilot's handbook does indeed say 450mph, and I can only think that it was in order to build in an extra margin of safety considering many fresh inexperienced pilots would be flying. Still I appreciate the job TF have to do, and you have to base your criteria somewhere. The pilot's handbook is as reasonable a place as any, if you're using them for all aircraft. Shame the RAF's one knocked 20mph off the dive speed, ah well! Keep up the good work! :salute:

Talisman
May-22-2014, 14:08
OK, here's what Vlerkies is getting at, I think.
The Spitfire cut-out seems to be OK, however, we don't see the appreciable LOSS in airspeed associated with the carb-failure that one would expect, if the cut-out really was a problem that needed solving. (and that matches the pilot's descriptions)

NONE of the below is posted in my capacity as a TF member, any issues arising are not the opinion of TF, just me!

I've just had a wee look, and from 250mph (spit) or 400kph (109), I can push the nose pretty steeply into a rapid dive of around 80 degrees nose-down.

The spitfire ASI will drop from 250mph to 220mph before I hit the dive angle and reduce the negative G. at that point the ASI climbs back up.
The 109 ASI will drop from 400kph to 350kph in approximately the same maneuver, then it starts to accelerate as the bunting stops, at the same time as the spit is recovering too.

So, whilst the Spitfire loses 12% of its airspeed in the "bunt", the 109 ALSO loses 12%.

In that respect, the "loss" of power does not currently appear to translate into any obvious loss of airspeed for the spitfire above the 109.
To my mind, this does appear to warrant further investigation.

Phil,

Tried your test with a stop watch and found that the speed scrubbed of to similar values to you, but the Spit took about 4 seconds longer than the Bf 109 to stabilise in the dive after bunt. Also, the Bf 109 was faster to 700 kph in the subsequent dive. Additionally, I could pull up from the dive to 700 kph in the Bf 109 very easily with no damage whatsoever each time (thought the controls were supposed to stiffen up historically?). With the Spit, I found it started to break up and lose parts on a number of occasions before it got to 700 kph.
So, still initial advantage to Bf 109 as far as I can see.

P.S. Bader said in his book that he had caught Bf 109's in a dive when flying a Hurricane, so there should not be that much drama for a Spit.

RAF74_Buzzsaw
May-22-2014, 14:55
Buzzsaw, Don't get me wrong here..I'm not unhappy in any way with the way things are in the sim. It's great. Also I'm not on about absolute speeds achievable under these or those experimental conditions. I was merely enquiring after the origin of the Vne (maximum permissible speed) figure for the Spit. The approved and tested Vne for Mk1 and Mk II Spits was 470mph IAS. The production Mk1 wings were stiffened to accept that speed over the original 380mph IAS specified for the prototype K5054. All production model dive testing was done to the higher speed and it's a well documented figure so I was curious, that's all. The Pilot's handbook does indeed say 450mph, and I can only think that it was in order to build in an extra margin of safety considering many fresh inexperienced pilots would be flying. Still I appreciate the job TF have to do, and you have to base your criteria somewhere. The pilot's handbook is as reasonable a place as any, if you're using them for all aircraft. Shame the RAF's one knocked 20mph off the dive speed, ah well! Keep up the good work! :salute:

I am aware of the testing which went on, I have a copy of Eric Morgan and Edward Shacklady's book SPITFIRE: THE HISTORY, Alfred Price's books, more original data than you can shake a stick at.

Yes, there are sources beyond the pilot manuals for the better known aircraft which detail testing of dive speeds... but what about the less well known aircraft?

For example, we have the pilot's manual for the Fiat G-50, which lists the recommended dive speed, but no other data on more detailed dive testing about exactly what the limits were. Very likely the G-50 could dive safely to a higher speed than is recommended in the manual... but we don't know what that speed was.

So do you make an exception for the Spitfires and 109's but not for less well known aircraft? For example, where are the tests for the Heinkels? For the Gladiators? For any number of other aircraft?

We have made the decision to base the recommended max. dive speed for all aircraft on the figures in the Pilot's manuals... these are available for almost all aircraft, this way we can standardize values.

As has been mentioned, in fact, you can exceed the max. dive speed in many instances and recover safely, the figures are not hard limits... effectively the allowable limits are higher. But you take a risk when you exceed them. :salute:

Steve D
May-22-2014, 20:59
I am aware of the testing which went on, I have a copy of Eric Morgan and Edward Shacklady's book SPITFIRE: THE HISTORY, Alfred Price's books, more original data than you can shake a stick at.

Yes, there are sources beyond the pilot manuals for the better known aircraft which detail testing of dive speeds... but what about the less well known aircraft?

For example, we have the pilot's manual for the Fiat G-50, which lists the recommended dive speed, but no other data on more detailed dive testing about exactly what the limits were. Very likely the G-50 could dive safely to a higher speed than is recommended in the manual... but we don't know what that speed was.

So do you make an exception for the Spitfires and 109's but not for less well known aircraft? For example, where are the tests for the Heinkels? For the Gladiators? For any number of other aircraft?

We have made the decision to base the recommended max. dive speed for all aircraft on the figures in the Pilot's manuals... these are available for almost all aircraft, this way we can standardize values.

As has been mentioned, in fact, you can exceed the max. dive speed in many instances and recover safely, the figures are not hard limits... effectively the allowable limits are higher. But you take a risk when you exceed them. :salute:

Like I said, fair enough. :) I've got Spitfire, the History too, it's a massive read. And the Alfred Price one. Jeffery Quill's book, Spitfire, a Test Pilot's story is also quite illuminating as he was at the sharp end of Spitfire testing throughout its life, and it's an easier going read than the Morgan/Shacklady book, however the books serve different purposes. I'd like to find the definitive reason for the difference between the Spit Pilot's manual Vne figure, and the actual manufacturer approved figure. As I said, my guess is additional pilot safety especially as regards novice pilots, but I'd be interested to find out if that guess is correct....BTW, I'm not suggesting it be changed. I think you do a fine job in the face of conflicting information, anecdotal 'evidence', this report, that report, you name it. It seems that if you look hard enough you can find data to 'prove' that any given plane was either rubbish..or brilliant! ;) As I said, the pilot's manual is as good a reference as any.

Cheers!

Vlerkies
May-23-2014, 03:25
Phil,

Tried your test with a stop watch and found that the speed scrubbed of to similar values to you, but the Spit took about 4 seconds longer than the Bf 109 to stabilize in the dive after bunt. Also, the Bf 109 was faster to 700 kph in the subsequent dive. Additionally, I could pull up from the dive to 700 kph in the Bf 109 very easily with no damage whatsoever each time (thought the controls were supposed to stiffen up historically?). With the Spit, I found it started to break up and lose parts on a number of occasions before it got to 700 kph.
So, still initial advantage to Bf 109 as far as I can see.

P.S. Bader said in his book that he had caught Bf 109's in a dive when flying a Hurricane, so there should not be that much drama for a Spit.

Bader said a lot of things, he also said in the vid he could not go nose down and had to half roll or stay up ;) but let us not let that get in the way shall we.
You know as well as I do that catching any plane depends on the initial engagement and energy of each.
I can show you account of P-51's turning and 'catching' and shooting and hitting a Mig15 as well.

The control compression in the 109 was significantly changed already, in 4.1 I think, feel free to start a thread on it if you think it requires more work. It would be an interesting discussion.
I hardly think its easy to pull up at 700, damage will come if you exceed that level to around 750, then you loose bits and pieces in a random sort of way.
I concur with you on the Spits only from the point that when they 'nose down' ;) and follow me in a dive they will break off around the 650 mark, and I sort of bank on that happening cause they are right on my tail.

Steve D
May-23-2014, 06:41
Historically the ailerons, elevator, and rudder got very heavy on a 109E at high speeds, combined with restrictive lateral stick movement and no rudder trim made it difficult to manoeuvre at dive high speeds - 400mph plus. RAE findings. Also historically early mark Spitfires could be safely dived to 470mph - 753kph IAS - the manufacturer's Vne. (Velocity never exceeded) Production Spitfires were all dive tested to this speed for handling, integrity, instrument, and control function tests before release from the works. If lumps had started falling off them on a regular basis, they would obviously not have been cleared for this speed. In the sim though lines have to be drawn for consistency across the board and as Buzzsaw has pointed out, accurate test data isn't available for all aircraft, whereas Pilot handbook data pretty much is and so that's what's used. The pilot's handbook shows 450mph IAS as the max permissible speed for the Spitfire. My guess is they were building an extra margin of safety for novice pilots, but there we have it.

92 Sqn. Philstyle (QJ-P)
May-23-2014, 06:56
Additionally, I could pull up from the dive to 700 kph in the Bf 109 very easily with no damage whatsoever each time (thought the controls were supposed to stiffen up historically?).

Hi Talisman, thanks for also lookign at this in a systematic manner. This kind of thing is much more reliable than people's anecdotes from their combat experiences - when a 100 other things are going on at once!

I would suggest that pilling up in a 109 at 700kph is not "easy". It requires a gentle approach.
If you yank to full deflection you'll be in trouble.

Talisman
May-23-2014, 10:23
Hi Talisman, thanks for also lookign at this in a systematic manner. This kind of thing is much more reliable than people's anecdotes from their combat experiences - when a 100 other things are going on at once!

I would suggest that pilling up in a 109 at 700kph is not "easy". It requires a gentle approach.
If you yank to full deflection you'll be in trouble.

Phil, you can bet I was certainly not yanking the stick to full deflection, LOL, credit me with some experience. But here is the thing, I would not class myself as experienced in the 109 and this test was the first time I had taken a 109 to 700 kph plus in a dive. However, the first time and every time when I repeated the test, I did pull out easily with no damage. Yes, I had to take care, naturally, but it was easy to be gentle on the stick and add trim up gradually; in fact I found the 109 was able to pull out of the dive much quicker than I expect and I got more confident each time I did it and did not feel the fear and apprehension that I do in the Spit at 420 mph for example. I am not complaining about this, I am mentioning it because it is something I learnt about the CloD Bf 109 in the test I did. I don't go over 420 mph in a dive in the CloD Spit as it is far to risky in my book, as when over that speed I have frequently lost parts of the plane and sometimes crashed. As I understand it, the Bf 109 was historically likely to have an initial advantage in the dive during the BoB, so no complaints from me on that score. I have every sympathy with the task that TF have in trying to represent the aircraft in this sim.

P.S. I did my test with BCO engaged in the Spit and WEP engaged in the Bf 109.