It´s back: High Alpha

[Monostripezebra]

https://www.youtube.com/watch?v=AzuIyYG5IeI

some practical aplication:

https://www.youtube.com/watch?v=5BqwV5QoLmQ

[216th_Lucas_From_Hell]

Nothing like a good Zeebra video! Excellent, as always

[Monostripezebra]

Trying out several other planes, it seems so far the Il2 is the best/worst

 

Pe2 has a very stable sideslip (hanging the plane against the wing drop tendency) which can go very low speed with flaps and airbrakes..

https://www.youtube.com/watch?v=w8PjBLNAdgo

 

with unqual trust and full fuel, the series87 archies some funny alpha, too

 

https://www.youtube.com/watch?v=tNGaQphwjJw

Edited September 24, 2017 by Monostripezebra

[56RAF_Roblex]

Now you need to get the PE2 to hang on it props over a target while someone in the lower gun looks out and tells you when to drop your bombs :-)

[19//Moach]

truth be told, I do not suspect any of this behavior is really wrong as one might think...

 

I used to fly gliders, several eons ago, and we had this very thick-winged WW2 era trainer in our aero-club, in fact this very same plane here:

 

those thick airfoils gave it some rather curious stall characteristics, instructors would say that if you brought its nose up just right, you could hold the stick against your belly all the way and instead of dropping like you'd expect, it'd stay nose high with a stuttery buffeting as if it were descending steps of a stair. and it would keep like that until you let it go.

then in training, they'd give it a more determined pull-up, so that it would carry over all the way to a full stall at the top

 

seeing what you're doing with the IL2 there reminded me of it.  

 

it strikes me that you're not actually doing impossible things where it should have stalled.  because actually, you have stalled, for all it's worth, but you're not letting the nose come down.

so even though the airflow is no longer smooth over the wings, you can still muscle out some (rather unstable) scraps of lift by sheer brute force

Edited September 24, 2017 by 19//Moach

[216th_Lucas_From_Hell]

Cool story, Moach! Brazilian F-5E pilots used to dogfight French M2000C and other F-16 pilots using a similar technique. Though the Mirage and Falcon are much better aircraft in both technology and manoeuvring terms, they both rely on advanced fly-by-wire systems.

 

In a close fight, the Tiger would force vertical scissors and once the speed dropped enough it would pull its nose up and stall like that for a while. The modern birds would try to follow but once speed and AoA approached the limit the FCS forced the nose down against the pilot's will. In this brief interval the Tiger dropped the nose too and had an easy 6 o'clock shot.

[56RAF_Roblex]

truth be told, I do not suspect any of this behavior is really wrong as one might think...

 

I used to fly gliders, several eons ago, and we had this very thick-winged WW2 era trainer in our aero-club, in fact this very same plane here:

 

those thick airfoils gave it some rather curious stall characteristics, instructors would say that if you brought its nose up just right, you could hold the stick against your belly all the way and instead of dropping like you'd expect, it'd stay nose high with a stuttery buffeting as if it were descending steps of a stair. and it would keep like that until you let it go.

then in training, they'd give it a more determined pull-up, so that it would carry over all the way to a full stall at the top

 

seeing what you're doing with the IL2 there reminded me of it.  

 

it strikes me that you're not actually doing impossible things where it should have stalled.  because actually, you have stalled, for all it's worth, but you're not letting the nose come down.

so even though the airflow is no longer smooth over the wings, you can still muscle out some (rather unstable) scraps of lift by sheer brute force

 

The T21, a high wing glider like yours,  used by most RAF cadets up until the 70s was almost impossible to stall as well.  It would just 'mush' down like a parachute if you insisted on holding the stick back and as soon as you released the stick it just recovered instantly.   

 

[Lusekofte]

You see this is what I do not understand . The IL 2 is heavy in the game, and he fly it like a heliumbaloon. Same with the HS129 all what you expect with it until you turn and turn like one wing is hanging by a wire. 

I never pushed the IL 2 outside its flight envelope, within this it is very realistic. But now I believe nothing anymore 

[Monostripezebra]

A glider beeing stable downwards (In german called "sackflug") is nothing new and even the Fieseler Storch is known to have been able to do it. But that is a different phenomen: It results from actually not beeing able to raise the nose to any higher AoA due to wing thickness/leading edge design in combination with the elvator design and elevator authority and CoG issues. I occasionally fly a Mü13 derivate called "Bergfalke" that can do this, so I know that behaviour.

 

I think what we have in BoS right now (and what we had similarly in a much earlier version) is the overmodeled propwash over the elevator  together with simplified wing flow condition. "Abschmieren" falling over ones wing with a part of the movement vector in the general wing tip direction generates a lot of lift, other then it would in the real world. Something I liked about the old P40 model in BoS was, that it actually had a good depiction of departure from a stall into a spin. Off course it wasn´t really that combatusable with the insane amount of energy loss in maneuvering, but the other aspect was actually pretty well modeled. A model is simply always a model and there is NO fligthtsim now or in the near future that can do everything right.. it is simply not possible. This is far from any "OMG THE FM!!11!" intention, just a test of what we have and my honest oppinon is that new FM while correcting some aspects has also introduced other less realistic ones and one particular area there is the departure from a stall into a spin. Overall, landing and flying on the edge of the envelope have gotten simpler and easier, but not necessarily closer to real plane behaviour. That is a good thing for the accessability aspect of the game (to new players) but not necessarily a favourite of the old afficionados, like myself.

 

I miss those classic "unexpected" departures, which are a bit trademark of the faster wing profiles from the 30ies/40ies which I think where partly excellently modeled previously:

Edited September 24, 2017 by Monostripezebra

[1PL-Husar-1Esk]

I hear you - where are those stall &spins accidents during take offs or landings, so common during war. Sometimes i see how H111 is going straight up after just take off I believe it couldn't do that - just by looking it's "strange". There's the fact that most VP have huge experience and do fly like they want but any way your videos showing not related to that issue.

 

 

Edited September 25, 2017 by 307_Tomcat

[216th_Jordan]

I absolutely agree that the propwash effect departs from what I would expect at greater AOAs. I would firstly think that due to high AOA the stream by the prop will be different than in normal flight (distorted/ reduced) and that this would result in at least a lot of buffeting in the affected wing area. (due to a simplified flow model which must be employed to reduce CPU cycles you would still get laminar flow due to combined airflow vectors in the propwash area) Also I think that the control surfaces in the outer wings which are stalled in that condition should be a bit less effective.

 

I'm not an aeronautical engineer though, so these are just my theories.

[busdriver]

Cool story, Moach! Brazilian F-5E pilots used to dogfight French M2000C and other F-16 pilots using a similar technique. Though the Mirage and Falcon are much better aircraft in both technology and manoeuvring terms, they both rely on advanced fly-by-wire systems.

 

In a close fight, the Tiger would force vertical scissors and once the speed dropped enough it would pull its nose up and stall like that for a while. The modern birds would try to follow but once speed and AoA approached the limit the FCS forced the nose down against the pilot's will. In this brief interval the Tiger dropped the nose too and had an easy 6 o'clock shot.

 

Hmmm...those must have been some extremely aggressive (fangs out, hair on fire...or alternately...all dick and no forehead) Electric Jet pilots with low SA and poor technique (kudos to the F-5 guy). I never had any doubt about killing an F-5E...the Hornet with it's superior Hi AoA nose authority was a more difficult 1-v-1 opponent for me. If the Electric Jet pilot didn't learn his/her lesson the first time, then probably any jet could beat them. I guess what I'm saying is the EJ pilot probably flew to the "wrist" instead of to the "elbow" (got too close). It happens.

[6./ZG26_Klaus_Mann]

[1PL-Husar-1Esk]

Looking at this one would think how on earth pilots get killed in stalls accidents ?

[6./ZG26_Klaus_Mann]

Looking at this one would think how on earth pilots get killed in stalls accidents ?

Lack of Music. 

[II/JG17_HerrMurf]

Lack of Music. 

OK, that was funny.................

[CUJO_1970]

Looking at this one would think how on earth pilots get killed in stalls accidents ?

 

Probably because they are flying actual aircraft that have to deal with actual physics.

 

Spitfire vid would be more appropriate with Benny Hill theme song.

[216th_Jordan]

Its clear that this is a propwash effect. I made these tests some months ago too. Combined with propwash the root section of the wing is usually below critical AoA resulting in very high AoA to normal airflow.

I do not know how propwash does behave at this high AoAs so I cannot make any reasonable claims about this other than it seems a bit high. In your vid it is however apparent that there is mostly quite enough airspeed for directional control (130 kph+)

 

 

BTW: Regarding real life stalls: Stress is the most determining factor, sometimes you just forget how to properly fly a plane. then also you don't have to fight 5N on a joystick but maybe quite a bit higher forces.

Edited October 17, 2017 by 216th_Jordan

[Monostripezebra]

Oh good. the spitfire looks like we could have all sorts of fun in her... Maybe I´ll get one later, when I can play BoS again without that bufferman bug.

[1PL-Husar-1Esk]

Its clear that this is a propwash effect. I made these tests some months ago too. Combined with propwash the root section of the wing is usually below critical AoA resulting in very high AoA to normal airflow.

I do not know how propwash does behave at this high AoAs so I cannot make any reasonable claims about this other than it seems a bit high. In your vid it is however apparent that there is mostly quite enough airspeed for directional control (130 kph+)

 

 

BTW: Regarding real life stalls: Stress is the most determining factor, sometimes you just forget how to properly fly a plane. then also you don't have to fight 5N on a joystick but maybe quite a bit higher forces.

That spiraling slip stream produced by propwash can increase lift on wings that much? Edited October 18, 2017 by 307_Tomcat

[216th_Jordan]

That spiraling slip stream produced by propwash can increase lift on wings that much?

 

I really don't know. I personally would think that this turbulent air is getting very problematic at slow speeds and high AoA and that there is a simplification in the simulation model.

[Monostripezebra]

It´s a game.. the whole dynamics on the very edge of flight are not what would happen in the real world and in the real world you would not play around with those things down low ever. Propwash does increase lift and some planes like the OV-10 Bronco really take a lot out of it..  to the extend it doesn´t fly well on one engine like at all..

 

But I think the biggest thing is the slipping down over one wing speedincrease that goes directly into the wing flow condition on BoS that really is different in real life and results in more controlability in BoS then what you would find if you´d do that for real.

[6./ZG26_Klaus_Mann]

Wings will just produce the same amount of Lift no matter what Direction you're going?

[Monostripezebra]

Wings will just produce the same amount of Lift no matter what Direction you're going?

 

Have not tested that yet, but definatly sideways airstream when falling into onesides wing is somewhat simplified in the sense that your forward speed stays the main variable for what is going on on the wing, I would assume. Albeit more testing is never wrong.. feel free to have a go at it: fly high alpha and try getting into a wingward slide.