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Old 12-30-2018, 06:58 PM   #11
msalama
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Easy peasy
Wow. Just... wow.

I know it's stupid of me to ask, but certainly no training wheels (game mode etc.) on? Now I have to confess having no real flight experience in the 109 - I've bought it and have test flown it a couple of times in an earlier version of the sim, but that's all - but I've got plenty of hours in the Mustang; and regardless of any possible ground physics changes, I absolutely cannot take off in it without inputting some right rudder and aileron even in the latest Openbeta. So is this perhaps an aircraft-specific bug or something, because what's shown in this video has got NOTHING whatsoever to do with reality?
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Old 12-30-2018, 07:35 PM   #12
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Every prop aircraft requires rudder and aileron input on takeoff and landing, this a because of engine torque. Sudden movements up or down cause a corresponding roll one way or the other. It's exaggerated with the 109 due to being small, high power, with a high and narrow wheelbase.

With the Mustang, you can power against the brakes to get control authority, this doesn't work with the 109, you start out using the brakes to control lateral movements, moving to rudder and aileron control as you gain speed. It also helps to apply some down elevator to keep the nose from pitching up as it takes off.


-note
I always disable flight aides. Against my religion.
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Old 12-30-2018, 07:47 PM   #13
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Originally Posted by msalama View Post
Wow. Just... wow.

I know it's stupid of me to ask, but certainly no training wheels (game mode etc.) on?

No training wheels and full sim.
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Old 12-30-2018, 08:21 PM   #14
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Rudder wasn't used, but toe brakes - right toe brakes - were... That explains why it worked, I guess ?

Actually, I have to say that DCS WW2 modules are the only reproductions of prop aircraft where I can feel the need to apply rudder, inflight, without having to look at the turn coordinator.

In combat the need for rudder input differs from module to module, but when required, you feel it naturally, and not by "being told"....

In other games, sometimes a whole lot of sideslip is being indicated by the turn coordinator, but without looking at it I wouldn't tell from the feedback of my virtual aircraft.
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Old 12-30-2018, 09:10 PM   #15
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Originally Posted by birdstrike View Post
if im not mistaken such a video already exists in the groundphysics thread.

and i completely agree with your statements about the real life behaviour of ailerons and rudder...

but i just cannot observe them that way in dcs.
especially in the 109, in vertical manouvers at stall speeds, its the rudder that all of a sudden seems to cause adverse yaw effects and not the ailerons.

with this statement i dont mean that adverse yaw is not modeled for ailerons,

(i know it is modeled)

but just that its definitely easier to climb higher before stalling when using the ailerons to keep the plane on the vertical path instead of trying to adjust with rudder...especially in the period close before the stall happens...this doesnt mean i am of the opinion that in dcs no rudder is needed at all though either. you will still need right rudder.

but its better to just give little right rudder at the start of your vertical manouver, and then dont move it anymore until the stall happens(even if the slipball shows drastical slip). and avoid the stall as long as possible with the ailerons. this might be connected with my previous observation, confirmed by others who tested this as well, that slight to medium slips dont seem to cause any drag at all. but thats an assumption on my part that there is a direct connection with the above.

i know this thing has slats which keeps the ailerons longer effective than without..but still.

i can also observe, that on the ground on takeoff, right ailerons all of a sudden keep the nose from drifting the the left, where even full right rudder doesnt do its job.(in dcs of course, not in real life)

these are my personal observations in dcs, flying the 109 since its beta release.
OK, let's take a look what is the result of lack of proper right rudder input in flight. Truly trimmed plane must fly with zero bank and have constant heading. If you have improper rudder input (not centered ball) and wings in level by ailerons input, you will have uncompensated side force causing slight flat turn. Of course, it can be compensated with a small bank...

But ailerons at TO run is not more than a placebo... In the best case, otherwise they can give opposite effect on yaw.

And yes, can you explain how right brake is not an equivalent of right rudder. The only difference I see is a dead friction surface... after this TO.
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Old 12-31-2018, 04:45 AM   #16
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this a because of engine torque
Plus the prop causing a spiraling slipstream making its thrust asymmetrical. I know this, as do most folks having ever flown these birds, even virtually. It's why I was a bit bewildered by the video up there
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Old 12-31-2018, 07:06 AM   #17
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Never know, I was just offering my experience in.general not directed at anyone :p I did add the caveat that I play with flight aides off, which appeared to be enabled up there =)
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Old 12-31-2018, 07:29 AM   #18
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Originally Posted by zhukov032186 View Post
Never know, I was just offering my experience in.general not directed at anyone I did add the caveat that I play with flight aides off, which appeared to be enabled up there =)
As I said - all aides were turned off.
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Old 12-31-2018, 08:42 AM   #19
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Aides off, and you could still maintain your heading with wheel brakes only, taking off with approx. 1.4 ATA on the MAP gauge it seemed. This can't be right...
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Old 12-31-2018, 10:15 AM   #20
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OK, I'm stumped. Made a dummy test pilot, hopped into the Biffer, killed myself a couple of times before managing to survive a couple of hair-raising takeoffs on low ATA - and, surprisingly, survived the landings too (the landings are much easier, it seems). The engine torque is MURDEROUS and there's no way on earth I could've taken off with just wheel brakes, just wouldn't have been possible at all. You geezers sure your Biffer isn't broken somehow???

PS / EDIT: and, oh, how do you trim this deathtrap for takeoff, BTW? Nose down somewhat I presume?
EDIT2: those clowns claiming DCS has no torque modelled should have their heads amputated, end of. Because they clearly have no need for the appendage.
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