Single Wing Flight

[NineLine]

I encountered this a second time a few weeks ago (for the same embarrassing reason :) ) and the % of 'wing off' was much greater than the track I posted on p1 - I remember thinking 'that's up to the gear' (much like the OP, although no damage at all to 'good' wing IIRC) - I was able to catch the roll initially, but couldn't keep the nose up - I was low so (stupidly) gave it full power in one swift move... and spun in :)

 

Right wing lost + Power on = right roll - which makes sense as that's the direction she 'squirms' under power on take off.

 

I don't think I kept the track - but will check - If I did we can all have a go :)

 

That's a similar experience that I had....

[Yo-Yo]

 

http://www.youtube.com/watch?v=yACauO2IF5k

 

Love this one :-) :

 

 

I guess, that's another problem - possibly, the new wing aspect is not taken in account.

[Anatoli-Kagari9]

Yes, anyway, it's a 1 in a million chance to recover, as I believe it's the case IRL.

 

Yesterday while I was playing with the aileron trim tab I took the chance to brake the wings of my Dora a few times and see if I could make it to the airfield... I always dived and pulled hard, and I certainly blacked out and on some occasions one of the wings broke ( never the two at the same time ). From there on was a ride directly into the ground ... Sometimes I could almost stop the roll, but no combination was sufficient to overcome the intense rolling moment I got at the start...

 

So, I guess that just like IRL it might be possible if the wing broke due to collision with another aircraft and not while pulling Gs, but even so, in DCS and IRL, being able to recover, and even more to land, is a 1 in a million chance, I believe :-)

[9.JG27 DavidRed]

I set a mission to have an explosion blow my wing off, there isnt much in the way of control available to me... but then I am not the greatest pilot either :) Point is though... its not like the aircraft flies like a dream with this kind of damage :)

 

i was thinking about doing that as well, but doesnt the explosion happen in the center of the airplane?how did you get it to explode on the wing?

[Anatoli-Kagari9]

i was thinking about doing that as well, but doesnt the explosion happen in the center of the airplane?how did you get it to explode on the wing?

 

 

It's easier to set a flight with a wingman, and then collide with him, approaching slowly in formation.

 

You can even chose the left or right wing to break :-)

[9.JG27 DavidRed]

for now, i always took a 500sc or 4x50sc and pulled high g's to break the wings.but this takes too much time...

sithspawn's solution would be ideal.

[Bucic]

To add to my previous replies in post #52 I'd like to reply to some bits I've missed previously/didn't have time to tackle them. I would also like to point out that if Yo-Yo's model is off it's off by 5% in a worst case scenario, not by 20%. In a way I wanted to off-load Yo-Yo from answering posts claiming '50% wrong!' by preparing the figure from post #62. I really encourage anyone to take a close look at it. As Yo-Yo said I overestimated lift reduction due to wing loss (see: wing lift distribution) and still what you'll see does not scream 'impossible to maintain stable flight!'.

 

It's better to use positive lateral reaction to the sideslip using rudder. By the way, asymmetric wing drag automatically creates sideslip of necessary direction.

So: right wing lost -> left yaw -> apply left rudder for some left roll? (because fuselage has low L/D ~ generates high drag)

 

(...)so you overestimate the effect of shattered wingtip.

My attention to the effect of the shattered wing tip is based on two elements:

- cascade drag effect of lots of irregularities (both structural and shattered skin/components)

- a significant abrupt shear of the wing thickness i.e. the wing ends without any favorably profiled and thin tip

Now, I can imagine arguments for discarding the influence of shattered wingtip but it's hard for me to accept it knowing how significantly the induced flow effects intensify at low airspeeds/high AoA.

 

In real world the lift distribution is close to elliptical, so the lost part of lift will be less. By the way, even for the rectangular wing this distribution is not rectangular.

If you want to have true picture of the forces/moments you must calculate and integrate them along the wingspan regarding real distribution

I'm aware of both aspects. It's just that my top-of-the-head integrating module doesn't work quite up to standard ;)

[Bucic]

you may find this interesting regarding lift distribution (the site has the equations, integrals, etc, so if you 're looking for a crude calculation of the forces after partial wing loss and are patient enough you could try it out ) :

 

[ATTACH]105109[/ATTACH]

 

this one depicts the calculation of the total wing load distribution (after taking into account lift, wing weight and fuel weight)

[ATTACH]105110[/ATTACH]

 

 

http://www.mathworks.com/products/symbolic/code-examples.html?file=/products/demos/symbolictlbx/Wing_load_model/analytical-model-of-aircraft-wing-loads.html

Thanks! I may actually use this one day :)

 

The (main) issue isn't the amount of lift generated, but the amount of torque around the roll axis. The outboard portion proportionally provides a lot of torque due to the moment arm. The lift distribution will change with the loss of the outboard portion of the wing, making the remaining stub the new outboard portion with less lift per foot due to spanwise flow. Hence, the lift loss will be greater than the lift on the now departed outboard section.

 

An aircraft can fly with X % of one wing removed. The opposite (remaining) aileron 'simply' has to deflect up to dump enough lift for the total moment contribution of the outer part of the remaining complete wing to equal zero.

 

The overall alpha then has to be increased in order to make the remaining lift equal the weight of the aircraft.

 

The limitations will be

a) When you cannot increase alpha to keep lift equal to weight any more without exceeding the critical AoA (stalling)

b) Running out of aileron authority, ie when the fully deflected remaining aileron is not able to dump enough lift to give you zero rolling moment.

 

Both of these will be airspeed dependant, i e you can generate more lift and have more aileron authority at a higher airspeed. To put it another way, you will stall at a certain airspeed (which will be higher than your normal airspeed) and at another airspeed you will run out of control authority to counteract the roll.

 

The question is: How much wing can you lose at the airspeed you are able to maintain - not "can it fly".

 

Any anecdotal evidence of the feasability of flight less part of one wing is pretty much useless (F-15, FW-190 with a smaller wing section lost, model aircraft), as it tells us only that it is indeed possible within certain parameters - and we already knew that. We cannot extrapolate to the case of losing the amount of wing depicted in the OP.

 

If we remain within reasonable limits, the estimate of an aeronautical engineer and pilot is that there would be no way for the aircraft in the OP to fly, even if restricting it to the flight dynamics perspective and leaving systems damage aside. Unload and enter a near-vertical high-speed dive, yes, some resemblance of control may just be maintained until the rather violent impact with the ground. I do not believe anyone will be able to show calculations showing otherwise.

I've opposed extrapolations as well but the logic behind some statements pro 'the model is fine!' is simple: the presented RL cases are with less of wings lost but some of them also show very low aileron deflections needed to maintain lateral controllability. So a reversed logic to the one below has been used:

To summarize. If an A/C without 80% (example only) of a wing has barely any margin of lateral controlability at cruise speed and then gets landed by the pilot at airspeed anywhere near normal landing (at near 0 bank angle), the model is incorrect.

 

Anyway, I don't think this discussion can move any further (assuming substantiated statements) until it's raining numbers.