Bf 109 takeoff problems

What makes you think so?

Because otherwise we would probably be given the chance to also set the ground adjustable elevator trim tab that exists in the 109.

ground adjustable elevator trim tab that exists in the 109

Does it? I've always thought it had rudder and aileron tabs only, plus a variable incidence tailplane without a presetable fixed tab.

take off

this is take off of bf-109 g12 preaty similat to k-4 i gues, I noticed one very interesting thing

check ATA gage its scaled to 2.0

ED give us 1.98 ata K-4

check during take off, stick hard to right so aleirons works at low speeds

check what ata pilot is runing we will not get 1.8 ata sound of db605 ever

another thing oil pressure durign start up rising ver yvery slowly not like in dcs launching in to sky like saturn V

Thx for the video grafspee…

It's interesting to notice:

.) not even 1,2 is used for takeoff power, while in DCS most "pilots" slam the throttle or use 1,4... Most of the time I see it at maybe 1,1 ATA in the video..

.) SLIGHT rudder input. Maybe there was some significant starboard wind component, but the amount of rudder used to correct for the drift is minimal, maybe due to the conservative ATA used ?

So, after watching the video I am even less surprised that with toe brakes only, aileron ( at near rotation speed and after airborne ) and correct pitch, the real thing can probably also be made to takeoff without rudder input.

@msalama : yes there are also ground adjustable elevator trim tabs on left and right elevators. You can easily glimpse it in RW footage but even on ED's Web page for the Bf109 K-4 here:

https://www.digitalcombatsimulator.com/en/products/planes/kurfurst/index.php

for example on the third photo from the left in the first row...

You can easily glimpse it in RW footage

Except that they're not necessarily trim tabs, but something else altogether (see the DCS manual pic f.ex.). Any SME guys around?

this is take off of bf-109 g12 preaty similat to k-4 i gues, I noticed one very interesting thing

check ATA gage its scaled to 2.0

ED give us 1.98 ata K-4

check during take off, stick hard to right so aleirons works at low speeds

check what ata pilot is runing we will not get 1.8 ata sound of db605 ever

another thing oil pressure durign start up rising ver yvery slowly not like in dcs launching in to sky like saturn V

I wish our needles bounced around like that.

If runway is long enough you can take off at lower ata but i think during war time they used militaty power (mw50 off if avilable) for take offs i assuming that runways werent so long like nowdays :)

But yeah slaming throttle instantly to max is never good idea. In dcs i slowly increasing throttle in all birds so it is actualy possible to take off without toe brakes in bf109, i was alwayes amazed how small vertical stab and rudder is on bf109 compare it to spitfire or p-51 even fw190 has much bigger rudder.

Bouncing needles that would be nice :)

Except that they're not necessarily trim tabs, but something else altogether (see the DCS manual pic f.ex.). Any SME guys around?

They're actually trim tabs, ground adjustable. Don't have the links to the various sources, and the DCS manual "obliterates" it in the blue prints, but that's what they actually are, and were used to...

Because otherwise we would probably be given the chance to also set the ground adjustable elevator trim tab that exists in the 109.

no...they had it working before. before they were officially introduced in the menu as a special tab option, ED had it in a lua file(its probably still there) , where you could adjust all three trim tabs.

according to Yo-Yo, they hardcoded the elevator trim tab on purpose so that its not adjustable by the enduser, and its not a limitation of the engine. they didnt give a real reasoning for doing this, except that the 109s tendency to pitch up is a safety design iirc.

Yep, I knew about that lua "trick" - I actually was the first to suggest, long ago here at the forums, for it to be used with the Fw-190 for rudder trimming :-)

And yes, I was aware it was "frozen" some versions ago. None of the "editable" tab settings produce effects now.

I finally recalled the same lesson with the BF-109 I learned awhile ago with A2ASims' warbirds for FSX/P3D: taking off with these high-powered engines on slight airframes is a dance between rudder and prop torque, mainly.

At least, in my head I keep it simple and reliable by thinking in those terms.

So, instead of by-the-book numbers (hold brakes, rev up to 1.35 ATA, let go, right-brake to stay on the runway and stick down and to the right to counter high torque with rudder and ailerons, then let go as you start taking off), I've developed a feel for when the prop torque is overwhelming rudder input (or, very initially, right-brake taps).

I therefore slowly raise throttle to gain speed. If the plane starts veering off to the left, due to prop torque, I back off, with full right rudder. Once rudder starts to really have an effect, I balance increasing throttle to increase prop torque to steer left on the runway, and holding or reducing rudder input slowly and carefully to steer right.

You can literally feel the tension between these two forces as you take off, and once you get it right (it's quite sensitive), you can nail it every time. Without any other inputs.

What drove me crazy at first was, simply, over-torquing the plane with too much throttle for the situation.

A good, strong reminder is if you add any throttle after descending at or near idle, at or near stall speed, for landing. You literally feel the torque jerk the plane in one direction, and it completely messes up your landing, if you're not careful.

Don't know whether this is "100% realistic" or not, don't care; it's fun once you get the hang of it, and works for all the prop planes in DCS, as it does for A2A's WWII fighters. That's certainly realistic enough for me! :)

take off

My take off looks that way

12 o'clock on porp/ prop manual

radiator flaps depends on outside temp if its very cold i keep then on auto if it is warm set them to full open

elevator trim nose full down

flaps at take off position

little right aileron

gentle throttle up, while accelerating i use only rudder to keep it straight ATA up to around 1.2(i am increasing power gradualy while bf109 is accelerating this way i dont need to apply full rudder at all)

i dont use toe brakes at all

when i feel the speed is good i rotate a little after take off i retract landign gear, flaps full up, prop on auto.

You reinvented the method how Red 7 is flown time to time... :)

A plane with quite a history, I see! :thumbup:

To Jurassic_LP: most of us have 500+, or 1000+, or 5000+ virtual take offs. So, even without (or few) "real take-offs", our brains and neuromuscular system ARE used to react to control such take off. When we try to take off a new but flagship virtual bird, if the take-off is totally wrong and catastrophic, there is simply a problem with the simulation. Our gran-pa didn't have the opportunity to virtually train as us- if taking off with real Spitfire or Bf109 were so difficult than in DCS, 80% of pilot (and warbirds!) should have been off before the war!!! I suppose the model is quite "right", but faaaar too much exagerated.... (same is true with engine management: we count the minute of X manifold pressure or temp... but real ww2 pilots said themselves they didn't really care so much).

Not the most beautiful takeoff, but without rudder input and unlocked tail wheel.

I am sure Yo-Yo meant to also not include the brakes. There is no other way to overcome that massive torque - you either use use right rudder, or right brake, or both as the pucker factor increases. :pilotfly:

Just go easy on the throttle, lock the tail wheel, hold full back at beginning of roll to keep tail wheel in contact with runway and use your toe brakes. Once the rudder becomes effective, let off the back pressure on the stick. Not much to it. I've only got about 8 or 10 takeoffs and landings under my belt. But it flies like any other warbird.

https://youtu.be/-v1XWEkCan0

The smoothest way I've been able to take off is by doing this:

1. MW-50 tank empty (no fuel and no mixture); With a full fuel load the nose violently pitches up once the wheels leave the tarmac.

2. Flaps up

3. Trim full nose down (2).

4. Tailwheel locked, full right rudder, a dose of right stick.

5. Smoothly increase throttle to 1.2 or 1.25 ATA

6. If the timing on your throttle advancement is at the right pace (not too fast, not too slow) you won't need to use the brakes at all.

7. You'll "feel" when the rudder kicks in--ease off the rudder

8. When the tail comes off the ground, the nose wants to kick left so you'll have to add more right rudder for that

9. Off you go into the wild blue yonder.

To Jurassic_LP: most of us have 500+, or 1000+, or 5000+ virtual take offs. So, even without (or few) "real take-offs", our brains and neuromuscular system ARE used to react to control such take off. When we try to take off a new but flagship virtual bird, if the take-off is totally wrong and catastrophic, there is simply a problem with the simulation. Our gran-pa didn't have the opportunity to virtually train as us- if taking off with real Spitfire or Bf109 were so difficult than in DCS, 80% of pilot (and warbirds!) should have been off before the war!!! I suppose the model is quite "right", but faaaar too much exagerated.... (same is true with engine management: we count the minute of X manifold pressure or temp... but real ww2 pilots said themselves they didn't really care so much).

Hu? I don't feel things "so difficult" in DCS 109 or Spit take-off..... It feels perfectly fine to me, tbh, difficulty wise. And I'm no super duper expert , but it's been a loooooong time since I borked a take-off in these birds.

I think the hardware used by us virtual pilots plays a huge role in these cases. We get over the limitations of the simulations tool we have by practicing easily without dying. IRL, there is many more "feedback" for the pilot that make these type of handling way easier, natural.

Since I moved to VR, and to a far better stick / rudder combo, it has made everything so smoother for handling the birds. And it's only giving a bit better feedback , a bit closer to what you get IRL. But I can anticipate the bird going wrong far better during take-off run, it's suddenly pretty easy and natural.

I think your hardware plays a big role in how easy you feel the thing is, and how much you need to practice to get the muscle memory (which kinda replaces much of what feedback is missing) right.

i think the question is, does take off with no rudder input and just breaks work in real life? i think the new ground physics are less demanding and thus not very satisfying.

i think the question is, does take off with no rudder input and just breaks work in real life? i think the new ground physics are less demanding and thus not very satisfying.

Do you have take off assistance on? I certainly cannot take off without rudder input, and actually often need to use toe brakes to adjust myself from veering too far off course! Recently had a terrible time taking off but realized it was dynamic weather creating turbulence even though it was set to 0 in the menu. From the amount of times I crashed when practicing though I would say it seems plenty difficult!

In my case I don't have the luxury of hardware rudder pedals with toe braking, so using keyboard and joystick (with included twist rudder) is extra-tricky. I'm at a huge disadvantage if realistic braking is included as part of the takeoff process. But I've learned to compensate.

It's all in your technique, ultimately.

certainly cannot take off without rudder input, and actually often need to use toe brakes

Me too, so I'd guess the ground friction values have been changed again. Yet, I've seen comments from some members here that allegedly DCS models no torque and prop effects at all. Huh?

i think the question is, does take off with no rudder input and just breaks work in real life?

The answer is yes but it won't be pretty. You will be buying some new tires and new brakes before too long. And you run the risk of a brake locking up on you on takeoff, which has killed more than one pilot on takeoff and landing. I personally saw this happen at Sun n Fun back in the late 90's with a Sea Fury. Not good.

So just use a little brake and rudder up to about 80kph. Then she should be on rudder alone. Of course if there is a crosswind you will have to cope with other controls. Pilots don't use just one technique all the time. Actually the best thing you can do is be slow and smooth with the throttle.