Bf 109 Weight and CG Question?

[Salty]

This is not to start a flame war or anything like that, just a question. I'm coming to COD with experience flying in FSX. Now I know FSX has limitations, in it's capabilities, so this question is subjective. I also know that in any attempt to model the flight characteristics of an aircraft that there is some give and take. This isn't meant to be a criticism of the ATAG TF Mod or anything like that, just a question of curiosity. I have flow the A2A Aircraft Hangar BF 109 in FSX for some time. That plane is modelled to be very tail heavy. So much so that taxiing and turning on the ground is somewhat difficult. The procedure for takeoff is even more non-intuitive. It really takes some force to make the tail come off the ground. Before you start your takeoff run, you push the stick forward and to the right, into the corner. This causes the tail to more readily come off the ground once rudder control is established and right aileron helps in keeping it straight down the runway. You have to let up on the forward force as the tail rises or you have problems. It's tricky and like the historical aircraft, you can go tearing off the runway very easy. So, I was landing the COD Bf 109 E-1 the other day, coming in slightly hot and after touch down and coasting for a distance, I applied the brakes and the aircraft went instantly arse over tea kettle. In the FSX Bf 109, you can safely apply the brakes after touchdown and you don't have to be afraid of ground looping. So finally the question, What was the criteria for modelling the weight and CG of the 109 in COD? BTW, I don't mind the model you have used. I just revert to the more standard method that most tail draggers require for takeoff and landing and stay off the brakes.

[Dutch]

What was the criteria?

What was the criterion? What were the criteria? Criterion singular, criteria plural. Sorry mate, I'm very bored tonight. Apologies. :D

[Wulf]

I've also wondered about this. My understanding is that brakes wouldn't cause an aircraft to ground loop in the same way that brakes wouldn't cause a car to flip end on end, if applied at high speed. Others may know for a fact but my suspicion is that this feature has just been poorly modeled.

[RAF74_Buzzsaw]

This is not to start a flame war or anything like that, just a question. I'm coming to COD with experience flying in FSX. Now I know FSX has limitations, in it's capabilities, so this question is subjective. I also know that in any attempt to model the flight characteristics of an aircraft that there is some give and take. This isn't meant to be a criticism of the ATAG TF Mod or anything like that, just a question of curiosity. I have flow the A2A Aircraft Hangar BF 109 in FSX for some time. That plane is modelled to be very tail heavy. So much so that taxiing and turning on the ground is somewhat difficult. The procedure for takeoff is even more non-intuitive. It really takes some force to make the tail come off the ground. Before you start your takeoff run, you push the stick forward and to the right, into the corner. This causes the tail to more readily come off the ground once rudder control is established and right aileron helps in keeping it straight down the runway. You have to let up on the forward force as the tail rises or you have problems. It's tricky and like the historical aircraft, you can go tearing off the runway very easy. So, I was landing the COD Bf 109 E-1 the other day, coming in slightly hot and after touch down and coasting for a distance, I applied the brakes and the aircraft went instantly arse over tea kettle. In the FSX Bf 109, you can safely apply the brakes after touchdown and you don't have to be afraid of ground looping. So finally the question, What was the criteria for modelling the weight and CG of the 109 in COD? BTW, I don't mind the model you have used. I just revert to the more standard method that most tail draggers require for takeoff and landing and stay off the brakes.

Yes, you are entirely correct.

The CoG of the 109 on the ground is completely mismodelled. When it is riding on all three wheels, it should be very difficult to tip it on its nose, even with hard braking.

The aircraft is as it was modelled by 1C, we haven't changed it.

This is an issue we have been aware of for quite a while, we'd like to do something about it, however at the same time we do this, changes would also include altering the landing characteristics, the off camber undercarriage wheels in the historical aircraft caused directional instability during both takeoff and landing when the tail was lifted, one of the reasons for the large number of accidents during takeoff and landing.

All of this requires quite a bit of rewriting of code etc. and at the moment it is not a high priority. At some point we hope to address this issue.

Anyone wanting to understand the 109's ground handling should have a look at this post I put up quite a long time ago, (just before we began work on the TF Mod) and which includes actual pilot accounts:

http://theairtacticalassaultgroup.com/forum/showthread.php?t=2482

[Kling]

What was the criterion? What were the criteria? Criterion singular, criteria plural. Sorry mate, I'm very bored tonight. Apologies. :D

intresting. Ive learnt something new today! :)

[Kling]

Yes, you are entirely correct.

The CoG of the 109 on the ground is completely mismodelled. When it is riding on all three wheels, it should be very difficult to tip it on its nose, even with hard braking.

The aircraft is as it was modelled by 1C, we haven't changed it.

This is an issue we have been aware of for quite a while, we'd like to do something about it, however at the same time we do this, changes would also include altering the landing characteristics, the off camber undercarriage wheels in the historical aircraft caused directional instability during both takeoff and landing when the tail was lifted, one of the reasons for the large number of accidents during takeoff and landing.

All of this requires quite a bit of rewriting of code etc. and at the moment it is not a high priority. At some point we hope to address this issue.

Anyone wanting to understand the 109's ground handling should have a look at this post I put up quite a long time ago, (just before we began work on the TF Mod) and which includes actual pilot accounts:

http://theairtacticalassaultgroup.com/forum/showthread.php?t=2482

Great reply Buzzaw!!
Factual, honest and to the point!

+1

[Gromit]

Oh boy, sounds like a can of worms for a code writer, wouldn't changing the Cog affect both ground and flight characteristics?

[RAF74_Buzzsaw]

Oh boy, sounds like a can of worms for a code writer, wouldn't changing the Cog affect both ground and flight characteristics?

That's the issue which requires a lot of work. 'Nuff said.

Another issue which we need to look at is overall undercarriage spring stiffness, right now all aircraft undercarriage springs are much too mushy... at the same time, simply increasing spring rate makes them too bouncy, we need to write code which allows the creation of shock absorbers. This is something which was outlined but not implemented in the game...

Lot's of work to do in MANY MANY areas... :doh:

[Salty]

Thanks for the response. I can appreciate the problems with correcting code. I agree, it's not high on the priority list. Maybe someday.

[LG1.Farber]

I wondered this same thing myself, however I concluded that you spend nearly all the time in the air rather than on the ground and so didn't mention it. However I think it gives TF and Buzzsaw credence that they are knowledgeable of such things and can instantly speak about them with authority.

[RAF74_Buzzsaw]

....you spend nearly all the time in the air rather than on the ground....

Exactly.

Our priority is to fix things which affect flight first, players spend very little time on the ground comparative to the time in the air.

But ground handling is definitely on the list.

[Wulf]

One of the features I'd really like to see implemented is a new 'enhanced' Spitfire bail out procedure. As I see it, I'd sneak up behind a Spit in the usual way and apply the standard medicine (lashings of cannon and MG rounds delivered at point blank). The Spit would then shudder momentarily in the air before bursting into flames (OK, at this point I realize it's becoming a bit fanciful). The flames would then quickly engulf the cockpit. Seconds later the hood would fly off and a smoldering pilot would struggle half way out of the inferno before looking back and either shaking a defiant fist or, giving me the finger. I then give him a quick burst and, clutching at his chest, he falls back into the blazing cockpit before the whole aircraft explodes in spectacular style as I zoom climb away to safety. Now, I appreciate that, like the 109 C of G issue this probably isn't a priority, but if it could be slipped into the next patch ...........

[Uwe]

One of the features I'd really like to see implemented is a new 'enhanced' Spitfire bail out procedure. As I see it, I'd sneak up behind a Spit in the usual way and apply the standard medicine (lashings of cannon and MG rounds delivered at point blank). The Spit would then shudder momentarily in the air before bursting into flames (OK, at this point I realize it's becoming a bit fanciful). The flames would then quickly engulf the cockpit. Seconds later the hood would fly off and a smoldering pilot would struggle half way out of the inferno before looking back and either shaking a defiant fist or, giving me the finger. I then give him a quick burst and, clutching at his chest, he falls back into the blazing cockpit before the whole aircraft explodes in spectacular style as I zoom climb away to safety. Now, I appreciate that, like the 109 C of G issue this probably isn't a priority, but if it could be slipped into the next patch ...........

3069

[Foul Ole Ron]

Is it just the CoG on the ground that was modelled completely incorrectly or is it the CoG of the plane in general and hence the in-flight characteristics as well are just wrong? I'm presuming the latter which makes it so hard to address with limited access to the code. Does the CoG change over time in the flight as fuel is burned, etc. or is it a constant value set by the developers?

Out of curiosity for those who have the A2A BF109 flight sim how do you find that flight model there compares to CoD's model? I know A2A flight sims are a level above CoD when it comes to fidelity but would be curious to know how it compares for general flight characteristics, workload, etc.

[buster_dee]

Let's keep in mind that, on the ground, it's not just the CG, but the CG relative to the location of the landing gear. The latter may be all that is mis-represented. With CG over the gear (like on Spit?), more nose-over, but less ground looping. Gear forward of CG (CG aft of gear), less nose-over, but more ground looping. Splayed gear was probably not the only factor in BF's ground looping.

With regards to A2A bird, I don't fly on very realistic settings, but I can say there's definitely the feeling that the tail is stubborn on the ground. I push the stick all the way forward when taxiing and still have to tap a break sometimes to get it turning. If I get impatient and add too much power, it tries to charge off straight again. To me, it feels right when based on what I've read about its tendencies.

[Kwiatek]

Well maby A2A 109 ground handling is more accurate then in CLOD but definitly in the air handling expecially stall and spin characteristic A2A is not even close. Landing is also too simplificated in A2A ( HSFX). The more close to reality is DCS P-51 expecialy in ground handling, take offs and landings.

But as we know TF could make miracles so we could hope that ground handling would be also improved ( as much as it is possible ) :)

[buster_dee]

I think "much improved" will take casual players by surprise.

"I'm leaning, and my tongue is sticking out to the left. Why can't I turn?"