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hnbdgr
Jun-24-2014, 09:42
Salute all,

I never paid too much attention to the slats on the 109, I mostly steered her gently with long curves, etc. so they probably didn't need to deploy very often. I recently switched to the spittie for several evenings - I think I can handle the spit quite well now, (bar overheating, sorry basha if you're reading this :) ) but I quickly got used to pulling steeper turns.

I've flown the 109 yesterday again and I think I must have been in my spit mode, because I was shedding energy like crazy. Went down from 3.5k to pursue a hurri at 1k and lost all of my E advantage within a minute. (surprised how those hurris keep up with you down low!) This made me watch my turns a bit more and I always kept an eye on the slats. Sure enough they were deploying more often than not. I was looking for some sort of audio or visual warning but I couldn't quite hear it. There is a tiny bit of shake when the slats deploy but you won't notice in combat.

How do you guys watch that the slats don't open too much?

And technical side question: do the slats have an indicator that could be used in the TF Devicelink interface?

many thanks!

badger

Vlerkies
Jun-24-2014, 10:00
There are no indicators as such other than the feel you have on the plane and the audio visual ques it gives.

The slats deploy automatically to prevent the wing from stalling.

You assessment is correct and they eat your energy like cancer, you were in TnB Spitty mode, and that Kung Fu is no good in a 109 if you want to stay alive.

Keep your airspeed up is rule 1 then you wont have an issue.

Here's a nice link demystifying them somewhat.

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

Edit: bare in mind in tight twisty fights they will deploy, nothing you can do about it and they are only doing what they are supposed to do, keep you up there.
The trick is to only pull the hard turns if you are sure you will get the result/shot.

9./JG52 Ziegler
Jun-24-2014, 10:52
Nice article Vlerkies and +1 to the airspeed.

Never pull hard for more than a second or so and only if gives you a solution or saves your butt. In the current patch the 109's have a rather narrow operating alt. I try and keep between 6k and 4k and give myself a 2k decent limit if at all possible. The rule of thumb is stay fast and always be climbing if your not engaged. It's money in the bank.

hnbdgr
Jun-24-2014, 11:53
Thank you Vlerkies for the advice + article.

Ziegler - I find I can escape anything even under 3k but don't have enough of a climbing advantage until after 5k to turn the tables on them.

Hence can't really do anything other then climb if i got a spit or hurri on my tail under 3k.

Vlerkies
Jun-24-2014, 12:39
Thank you Vlerkies for the advice + article.

Ziegler - I find I can escape anything even under 3k but don't have enough of a climbing advantage until after 5k to turn the tables on them.

Hence can't really do anything other then climb if i got a spit or hurri on my tail under 3k.

It really depends on the plane you are flying and the energy you and the guy behind you has at the time.
My E1 I pretty much fly below 4000m, it just looses to much HP above that. The E3/4's should be much better up there.

You will not always outclimb/outrun/outdive. Always try and put yourself in a position where you have and maintain the energy advantage, then you can do all 3.
TnB you will loose your speed and energy much faster than a RAF fighter so its not your primary tactic.

If you keep just a fraction above the enemy at all times you will open up options for yourself if things go pear shaped.
For me I will try and outclimb if I have really good airspeed only 450kmh and above.
If I am slow it's dive time, but you need a minimum of say 1500-2000m to give up.

Your 109 will accelerate faster than a Spit, initially. Thats the trick in building distance. The accelration in the dive is what buys you breathing space, not straight line speed.
You can also hold a ever so slightly higher airspeed in a dive, maximise that. Your dive speed can be up to 700kmh, they will be around 650 or so.

So, accelerate in the dive fast with your nose down and working the prop, till you get as close to the 700 as you can (alt allowing) When you get there ease the nose back to shallow out the dive as much as you can, in order to conserve the remaining altitude but still keeping the speed maxed (700) while diving at a less steep angle. You need to hold some degree of dive to maintain 700.
That will increase a good gap in most instances. Often the guys will break off or hang back at higher alt than you so don't turn round, they will be baiting you.
When you have the gap you can climb again, in a straight line never turning and rinse and repeat.

I have Spits chase me across the channel back and forth for half an hour like this already, flying solo and looking for a friendly plane.
If you see a friendly fighter just gently vector to cross a few clicks in front of him and sure enough he will latch onto the guys following you. Drag and bag then go home for a pint in the pub.
;)

gavagai
Jun-25-2014, 10:41
Slats do not deploy because of your energy state; they deploy because of your high angle of attack. Here is a nice graph showing what they do compared to flaps:

http://forums.x-plane.org/uploads/monthly_11_2011/post-1379-0-49093100-1322514764.jpg

Slats move the transition from laminar to turbulent airflow closer to the leading edge of a wing. This allows for a higher AoA before a stall.

Some evaluators were very confident about maligning the leading edge slats of the Bf 109, but slats became ubiquitous post war. You can see them on aircraft like the F-86 Sabre, F-16 Falcon, and every commercial jet that's carried you as a passenger.

You can read some good accounts of the 109's leading edge slats here: http://www.virtualpilots.fi/feature/articles/109myths/#slats

5th_Tot
Jun-25-2014, 11:38
the only indicator you can go for are vapors on the wing edge. while your looking back maneuvering you don't always see the wing but the vapors. vapors=high AoA=slats coming out.

Vlerkies
Jun-25-2014, 12:56
Slats do not deploy because of your energy state; they deploy because of your high angle of attack. Here is a nice graph showing what they do compared to flaps:


You are of course 100% correct gavagai. The link that was provided explains that perfectly.
The mention of speed though (indicator) is that if you keep your speed up, as well as the energy (both of which you loose in tight turns) 'and do not pull the tight turns' the slats will not deploy, as you wont loose lift.
They deploy when the wing looses lift and from my understanding directly related to the air pressure differential around the wing when it starts to stall, in all cases this is when you are turning to hard.

In short fly smooth and fast.