Single Wing Flight

[Yo-Yo]

Hi,

 

Was just wondering if the flight model for single wing flight will be fixed in a later version? I can fly the Dora with a single wing (actually a bit of wing left) and land it ok also.

 

Anyone else have this?

 

 

Just for curiosity. How about this plane? To liberate you from the necessity of measuring the photos - it has 7/13 of one wing off. The wing is rectangular so it's easy to determine areas.

 

What do you think - if it's possible for this plane not to drop its wing and continue flight?

 

P.S. Let call this plane X-plane.

[Corrigan]

Yo-Yo, I just wanted to say, I love you.

[Yo-Yo]

Right. Because we can safely assume that in every video of a plane losing part of all of a wing, some other factor other than the obvious wing loss accounts for the death spiral every time. Also: in the one where the plane goes left after losing the wing, that aircraft was already most of the way over the apex of its roll, after losing its wing, momentum caused it to continue its roll, and you can notice that the rate increases on the side with less wing(and less drag) after it flops over.

 

Stop, stop... the plane we are talking about (0-14) was rolling LEFT. Right wing lost its part. Right wing lost a part of its lift. So, the moment must decelerate roll, but instead of it the plane accelerated left roll as if right wing rose as a Pinoccio's nose...

 

To be serious, it lost so small part of the wing that it's nothing regarding "dead spiral" or "dead spin"...

[Roadrunner]

noone said an aircraft needs to be symetrical, aye?

 

a sudden loss of a wing will cause something, not arguing there, but after or if the pilot recovers, a flight is most likely possible.

 

other aircraft where build that way, see here:

 

BV-141

 

 

yo-yo, wouldnt it be interesting to programm a flight model for this one? :D

 

RR

[Aeons]

Just for curiosity. How about this plane? To liberate you from the necessity of measuring the photos - it has 7/13 of one wing off. The wing is rectangular so it's easy to determine areas.

 

What do you think - if it's possible for this plane not to drop its wing and continue flight?

 

P.S. Let call this plane X-plane.

 

sure everything can fly with enough momentum/energy e.g. rockets without any wings that produce lift etc, a rock being thrown into the air.

 

why dont u make an exact replica aerofoil and Body of a Dora then cut the wing almost completely off and throw it and make it fly (controlled flight) for longer than 5 secs please.

[lesnyborsuk]

I love topics like this one - you can learn something new :).

I am no expert in aerodynamics, but I have some minor knowledge (I am private pilot in rl).

I am wondering - all the YoYo's examples in this thread are based on smaller models. Including radio controlled ones.

 

I think that what OP wants to discuss is if this behaviour could be scaled to larger planes. Isn't there any other air properties that interfere more in smaller models? Like, in example, air viscosity? Weight of those models could be not directy proportional to larger planes as well, when comparing scales.

 

In previous posts I could see photos of WW2 planes flying without significant parts of wings and it is amazing. However, OP screenshot shows Dora with around 80% wing missing (rough guess).

It is not a secret that anything can fly straight with enough speed and energy. Someone here brought up story of israeli F15 landing without a wing. The point there was that pilot had to keep significantly larger speed to keep flying straight and then land safely.

 

If I understand correctly, OP could land Dora without needing much more speed.

 

As real world example I can bring Polish TU154 crash in 2010:

http://en.wikipedia.org/wiki/2010_Polish_Air_Force_Tu-154_crash

"Soon after, the aircraft began hitting trees. One, a large birch with a trunk 30 to 40 cm (12 to 16 in) wide, ripped off about 6.5 meters of the left wing, including the left aileron. The resulting asymmetrical lift caused an uncommanded roll to the left. Within 5 seconds, the aircraft was inverted, hitting the ground with the left wing followed very shortly thereafter by the nose."

 

Looking forward to read more information here :).

Edited September 25, 2014 by lesnyborsuk

[Yo-Yo]

sure everything can fly with enough momentum/energy e.g. rockets without any wings that produce lift etc, a rock being thrown into the air.

Sorry, but it's a pure demagogy - the question above was not about rockets, rocks, etc. It was about the board plane you see on the photo. And the term "flight" in this context means stable, controllable (if this plane is equipped with RC) gliding.

why dont u make an exact replica aerofoil and Body of a Dora then cut the wing almost completely off and throw it and make it fly (controlled flight) for longer than 5 secs please.

 

Because our discussed case is not a matter of an airfoil. It's a matter of lift distribution along the wingspan, wing planeform and aileron effectiveness that mostly depends on its relative area and span.

 

"Completely off" in your exagerrated estimation means 43% of remaining area of the one wing in real world.

 

If this small model had RC it would be stable up to its battery failure... but this model built to illustrate that getting part of its wing off the plane is able to stay stable if other damages or reasons (pilot's shock or death, for example) do not affect.

 

So, the question was direct, and the people are waiting for the direct answer.

[Yo-Yo]

I love topics like this one - you can learn something new :).

I am no expert in aerodynamics, but I have some minor knowledge (I am private pilot in rl).

I am wondering - all the YoYo's examples in this thread are based on smaller models. Including radio controlled ones.

 

 

The small models can be different in Re number, airfoils, but these factors act evenly for all aerodynamic surfaces. That's why the small model stability calculations are the same as for large planes. They always use generalised coefficients. So making a model to test one wing flying always has a goal to check forces/moments that can maintain force/moments balance

 

What about 2011 incident in Duxford?

 

http://www.youtube.com/watch?v=T_A4xdGFXoE

 

The Skyraider performed something like the rolls we can see on the guncam footage but... was able to recover and land safely.

[Soulres]

 

What about 2011 incident in Duxford?

 

http://www.youtube.com/watch?v=T_A4xdGFXoE

 

The Skyraider performed something like the rolls we can see on the guncam footage but... was able to recover and land safely.

 

The skyraider lost a wing tip, while the P51 lost half of its tail and stialled out, I think the fact that the A1 skyraider weighs more than the P51 had alot to do with it.

 

I think a Lighter weight mixed with a slower speed can make the diffrence.I know for Jets loosing just a wing tip can mean the end of a entire plane let alone loosing part of the wing.

[Yo-Yo]

The skyraider lost a wing tip, while the P51 lost half of its tail and stialled out, I think the fact that the A1 skyraider weighs more than the P51 had alot to do with it.

 

I think a Lighter weight mixed with a slower speed can make the diffrence.I know for Jets loosing just a wing tip can mean the end of a entire plane let alone loosing part of the wing.

 

Skyraider lost about 1/4 of its wingspan but if you find the video of its landing (the worst case because asymmetry issues becomes stronger as speed decreases) you can not see lateral or directional controls deflected fully to compensate.

 

P-51 lost nothing. The wingtip hits its belly and jammed controls.

 

Israelian F-15 lost almost full wing and landed.

Edited September 25, 2014 by Yo-Yo

[Aeons]

 

 

Because our discussed case is not a matter of an airfoil. It's a matter of lift distribution along the wingspan, wing planeform and aileron effectiveness that mostly depends on its relative area and span.

 

"Completely off" in your exagerrated estimation means 43% of remaining area of the one wing in real world.

 

So, the question was direct, and the people are waiting for the direct answer.

 

 

 

did you forget to include the "almost" out of my sentence on purpose(almost completely off)? Please look at my first post that created this topic and look at the pics and tell me if the wing is still 43% remaining actually look at the right aileron also.. its also damaged.

 

so the whole point of me creating this original post was to see if the flight model for the DCS DORA (not a paper plane) will be fixed.

 

Lets create a Kickstarter project to build an exact real life scale replica Dora with the same damage (min. left wing left, right aileron damage etc) and get someone to pilot it in real life :megalol:

 

Additional extras to the kickstarter project will be a parachute.

 

Any volunteers to pilot this Dora??:pilotfly::joystick:

[[DBS]TH0R]

Skyraider after the incident:

 

 

 

Aileron remained attached to the wing. Although probably non functional...

Edited September 25, 2014 by T}{OR

[Bucic]

.

 

So, the question was direct, and the people are waiting for the direct answer.

The main problem with this whole thread. The main question has been answered. It is possible that a plane...

 

But there's a lot of buts.

 

Even though I know I risk making a fool of myself arguing with Yo-Yo I would still like to share what I think may be off:

 

0. Maintaining lateral (roll) controllability requires use of ailerons and even rudder at some point. As airspeed decreases their effectiveness decreases as well. Hence, cruise without 30% of a wing is not comparable to landing without 30% of a wing.

 

0b. At extremely low airspeeds and low lateral controllability margin it may even be necessary to use the side of the fuselage to generate some lift that is not offset to CoG.

 

2. Any example involving contemporary F-15 like jets are completely out of place here for more than one conclusive reason.

 

3. I suspect the current model has a limited capability to remove appropriately large or small parts of A/C body plus the visualization is off with regard to what the model has established. For example I suspect that:

 

a) the model can remove either 50 or 75% of a wing and nothing in-between

 

b) at 50% removed at the model level e.g 60% loss is visualized

 

4. I suspect the current model

 

doesn't take into account the influence of shattered structures, e.g. shattered wing end. Plus shattered wing end (wingtip) has greater influence on aerodynamics than "shattered part of the fuselage" for example.

 

 

 

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 anywherenear normal landing (at near 0 bank angle), the model is incorrect.

Edited September 25, 2014 by Bucic

[Maverick-X]

Was the OP actually slowing down to land? In the 2nd post the last picture before landing shows a speed of almost 500km/h...

From my personal experience: a mustang tore off my right wing while I was at about 400km/h. I was able to return to the airport and decided to make a bellylanding without slowing down, in fear my plane would tilt over. Worked like a charm, given I almost ended up sliding into a fuel truck ^^

 

In terms of wing-off flying: the A10 is also known for being able after loss of roughly 50% of one wing. This would be a completely realisitc case, given you would not be able to maintain stable flight at lower speeds

 

0b. At extremely low airspeeds and low lateral controllability margin it may even be necessary to use the side of the fuselage to generate some lift that is not offset to CoG.

 

2. Any example involving contemporary F-15 like jets are completely out of place here for more than one conclusive reason.

 

To 0b: the fuselage does not generate lift

 

To 2: why not? same problem as long as you don't want to look at the dora exclusively. The problem remains the same:

You loose one wing -> lift imbalance. You get slower, airspeed goes into lift generation with second power, while area with first -> imbalance increases. Aileron should still be effective at this time, the question is, if it is strong enough to counter the momentum of lift imbalance

Edited September 25, 2014 by Maverick-X

[[DBS]TH0R]

And the landing:

 

[Bucic]

BTW:

1. Why is the severity of OP's wing loss consistently ignored? Neither of the posted RL examples is comparable to the OP's case.

2. How does it all relate to the recent DCS update which has fixed something with lateral controllability.

Edited September 25, 2014 by Bucic

[Yo-Yo]

The main problem with this whole thread. The main question has been answered. It is possible that a plane...

 

But there's a lot of buts.

 

Even though I know I risk making a fool of myself arguing with Yo-Yo I would still like to share what I think may be off:

 

0. Maintaining lateral (roll) controllability requires use of ailerons and even rudder at some point. As airspeed decreases their effectiveness decreases as well. Hence, cruise without 30% of a wing is not comparable to landing without 30% of a wing.

 

 

You are right. But the history gives us some examples of successful, safe and precise landing. If the plane can use flaps it increases its chances because lift distribution changes and the most significant part of it moves to the center symmetrical part of the wing. Anyway, the pilot of the Skyraider made absolutely right decision to perform 2-point landing to preserve speed and lateral balance ability.

Dora has the most effective ailerons ever designed for WWII planes so its chances are higher. Moreover, the model itself really had a discrepancy with damage visualisation and FM: as in the visual model the whole aileron was lost, the FM considered that its part along the remaining part of the wing is operative. So it has extra aileron effectiveness.

 

 

 

 

0b. At extremely low airspeeds and low lateral controllability margin it may even be necessary to use the side of the fuselage to generate some lift that is not offset to CoG.

 

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.

 

2. Any example involving contemporary F-15 like jets are completely out of place here for more than one conclusive reason.

It was an example that small model of a plane with the similar design shows the same results as a big plane.

 

3. I suspect the current model has a limited capability to remove appropriately large or small parts of A/C body plus the visualization is off with regard to what the model has established. For example I suspect that:

 

a) the model can remove either 50 or 75% of a wing and nothing in-between

 

b) at 50% removed at the model level e.g 60% loss is visualized

No, the visualisation areas mathches their FM values very accurately.

4. I suspect the current model

 

doesn't take into account the influence of shattered structures, e.g. shattered wing end. Plus shattered wing end (wingtip) has greater influence on aerodynamics than "shattered part of the fuselage" for example.

 

The real influence is much less than lift redistributing effect, so you overestimate the effect of shattered wingtip. It can add drag but not so much to spoil things dramatically.

 

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 near 0 bank angle), the model is incorrect.

 

You overestimate the area losses. But anyway, now the lateral control is as it must be, so it will be harder to do it.

 

But if you are so confident in your conclusions about the abilities of the real plane, would you like to answer the question about the model?

Edited September 25, 2014 by Yo-Yo

[airdoc]

As real world example I can bring Polish TU154 crash in 2010:

http://en.wikipedia.org/wiki/2010_Polish_Air_Force_Tu-154_crash

"Soon after, the aircraft began hitting trees. One, a large birch with a trunk 30 to 40 cm (12 to 16 in) wide, ripped off about 6.5 meters of the left wing, including the left aileron. The resulting asymmetrical lift caused an uncommanded roll to the left. Within 5 seconds, the aircraft was inverted, hitting the ground with the left wing followed very shortly thereafter by the nose."

 

Looking forward to read more information here :).

 

The TU-154 is a very large aircraft compared to a small WW2 fighter, and also much more complex. The type of damage that you are referring to (6.5 meters wing rip-off) would usually be considered as catastrophic in such big aircrafts.

 

I don't ever recall having read about an incident where a big airliner lost a significant part of the wing and managed to keep flying, let alone land safely. On the contrary, there are numerous stories of WW2 fighters having unbelievable sorts of wing damage and making it back. I 've also seen a photo of a P47 that had a prop strike at the terrain during a low-level strafing run that managed to keep flying with the prop bent(!!) and landed back (sorry don't have the link with the photo handy)

 

I think that the fact that airliners become unmaneuverable with such kinds of damage is a result of many factors.

 

Part of the wing getting ripped off would result in hydraulic pressure loss most of the times, which would render the aircraft *completely* inoperable. This is not usually a problem in ww2 fighters.

 

From an aerodynamics standpoint, i think that a fighter operates on much higher "safety factor" than a big airplane, meaning that it is able lose part of its lift-producing surfaces and still retain the ability to generate enough lift for it to fly (at a speed that is reasonable for landing); also the control surfaces are much more powerful, so that the aircraft can still operate with half of them missing. In a big airliner, even a rudder hardover can be fatal (many related incidents in the past).

 

And then there is the sluggish responsiveness of a big airplane that makes things even harder in case of structural damage : consider the roll rate of a fighter versus that of a big airliner (i.e 90 deg/s vs 10deg/s). A fighter aircraft would respond quickly and robustly in case of a sudden bank due to asymmetrical wing lift, whereas a big aircraft would react very sluggishly. This roll rate difference is also a sign of the relative weakness of ailerons in fighters vs big aircrafts. So, in a scenario where a part of a wing is suddenly ripped off along with the aileron, even with retained hydraulics, the aircraft would start a sudden bank, and the pilot would have to exert full opposite aileron to counteract; the roll response of the aircraft would now be about the half (due to the missing aileron) so at best the reaction would be a few degrees per second. In an ideal scenario the opposite aileron could maintain roll controllability within certain degrees of bank and the pilot would land the plane. But in most cases of larger aeroplanes that I 've read about, the aircraft starts a sudden bank, during which it pitches down quickly picking up speed, despite the pilots full opposite aileron; within a few seconds the aircraft is nosing down at a steep pitch and bank angle and at overspeed with various pieces of the structure getting ripped apart.

 

In general i think that we shouldn't compare the controlability of a big airliner with a small aircraft in case of structural failure. The small and simpler the aircraft build is, the more likely is it to endure such a failure.

 

EDIT :

found the P47 photo : http://www.vintagewings.ca/Portals/0/Vintage_Stories/NewStories-C/Lower%20than%20a%20snake/Lowdown24.jpg

Edited September 25, 2014 by airdoc

[[DBS]TH0R]

The TU-154 is a very large aircraft compared to a small WW2 fighter, and also much more complex. The type of damage that you are referring to (6.5 meters wing rip-off) would usually be considered as catastrophic in such big aircrafts.

 

In addition, the plane was flying low and slow (landing approach). Or in other words, no altitude to loose in order to gain speed and no where near its cruising speed.

[NineLine]

Here is a study on a UAV with wing damage, dunno if this has been shared yet.

Analysis of Partial Wing Damage on Flying-wing UAV_JAERO1719_Final.pdf

[Aeons]

BTW:

1. Why is the severity of OP's wing loss consistently ignored? Neither of the posted RL examples is comparable to the OP's case.

 

+1

[Yo-Yo]

Was the OP actually slowing down to land? In the 2nd post the last picture before landing shows a speed of almost 500km/h...

From my personal experience: a mustang tore off my right wing while I was at about 400km/h. I was able to return to the airport and decided to make a bellylanding without slowing down, in fear my plane would tilt over. Worked like a charm, given I almost ended up sliding into a fuel truck ^^

 

In terms of wing-off flying: the A10 is also known for being able after loss of roughly 50% of one wing. This would be a completely realisitc case, given you would not be able to maintain stable flight at lower speeds

 

 

 

To 0b: the fuselage does not generate lift

Negative. Fuselage does generate lift - more or less but it generates enough to produce sideforce that is at least 10% of the normal lift. See "coordinated sideslip" case. The second question is that L/D of it is low so the cost of this lift is large amount of drag.

But in the case of unsymmetric wing it does not play a role.

To 2: why not? same problem as long as you don't want to look at the dora exclusively. The problem remains the same:

You loose one wing -> lift imbalance. You get slower, airspeed goes into lift generation with second power, while area with first -> imbalance increases. Aileron should still be effective at this time, the question is, if it is strong enough to counter the momentum of lift imbalance

 

Could you provide an engineer's calculation? Because "get slower", "effectiveness" , "strong enough" are not numerical. But the devil is in numbers...

[Yo-Yo]

BTW:

1. Why is the severity of OP's wing loss consistently ignored? Neither of the posted RL examples is comparable to the OP's case.

2. How does it all relate to the recent DCS update which has fixed something with lateral controllability.

 

Neither of the posted examples use FULL AILERON DEFLECTION assisted with full rudder, yes? Even Skyrider uses only minor deflection even at touchdown speed.

 

I tried to explain that Dora ability to keep flying straight was increased, because in the FM a part of visually lost aileron was still considered functional. But it was only for the case of wingtip loss. THe case of 43% of the area (root part) is not changed.

 

THat's why I am asking the experts who made their judgement on the Dora, that it is impossible to keep the plane straight: please give me your valuable opinion about the board plane. It's not a matter of the math - it's real and it can answer at once and better. And nobody could say that this model is wrong...

[aaron886]

 

Great examples. One thing worth noting is that the Hornet produces significant vortex lift at the root as a result of the leading edge extensions, although I don't know if they even produce considerable results when scaled down as in that model.

 

Regardless, with 43% of wing area remaining, having reasonable control is completely believable.

[Yo-Yo]

Great examples. One thing worth noting is that the Hornet produces significant vortex lift at the root as a result of the leading edge extensions, although I don't know if they even produce considerable results when scaled down as in that model.

 

Regardless, with 43% of wing area remaining, having reasonable control is completely believable.

 

Anyway, this flat fuselage design works fine even for the model... :)