An-2 TBC-2MC (Honeywell remotorized) crashed in Naryan-Mar

[ATC Watcher]

Sailvi767 :

The AN2 certainly can stall. It won't stall decelerating in level flight because as you state it ends up just mushing into the ground at high AOA. Pitch the nose up 20 or 30 degrees however and it will decelerate rapidly and stall like any other aircraft.

I did my An2 type rating in Poland some 25 years ago but sadly never flown it afterwards, but I remember quite well that it indeed does not physically "stall" in the known sense . There is also no "stalling speed " on the airspeed indicator or in the Flight manual.
If my meorys erves me well what happens if you pitch up 20 or 30 degrees as you say and cut the throttle, is that at around 60 km/h the slats will automatically come out aerodynamically and you will start descending gently , you can keep control until about 40 K/h . If you try pitching up more up, below 40Km/h , you will loose control (not enough air flowing over the control surfaces) and the nose will come down automatically, putting you back above 40 Km/h . Quite an interesting aircraft.

What we see in that video is not a stall but something more dramatic as suggested here.

[Bend alot]

Page 144 of this PDF of the Fight Manual for a standard engine AN2 describes AN2 stalls (if that's what you call it).


https://www.dropbox.com/s/l8el56skt5...FCOM1.pdf?dl=0


Is it possible the ground witnesses just heard power being removed, and not an engine failure?

Any news on the survivors that may also include the pilot?

[ATC Watcher]

Thanks Bend a lot for this wonderfully translated flight manual. Helps get my memory back.. and more or less confirms what I described. It was long time ago.

Looking at the photo of the aircraft ( second link on original post ) I can see that this (quite ugly) engine modification probably changes a lot the flying characteristics of the airplane , would it be only its CG .
We're not talking about a standard fool-proof plain vanilla AN2 there...

[Bend alot]

One would think any engine mod would keep the same C of G and just give power improvements??

I do have all Maintenance and Delivery manuals for the AN2 in English for any that wish them free of charge (they cost me a lot).

[Kulverstukas]

This mod definitely changed a/c a lot. First, it's now tail balanced (and need additional 60kg or two additional acc at front for neutral balance). Second, this engine has much more power than vanilla An-2 also 5-blade propeller is more efficient. Rumors are, there was an usual way of Naryan-Mar pilots to "demonstrate" it by steep climb at TO.

[Kulverstukas]

certificate of airworthiness
p.14

[Propsforever]

From my Experience the AN2 will stall in one single Configuration, with a sharp break: Power ON and Flaps 30 or more. I flew the An2 for 10 yrs in my Sparetime, under AOC in Germany. Later i trained the new Pilots for the Company and had one nasty Experience. With a Pilot i knew very well we did the Power on stall, and the ( Aerobatic Qualified) Pilot got a bit slow with his feet, when the wing dropped. This ended with a 3/4 Incipiend spin and Recovery. You Need 4 Hands in this Situation, because in no time you are above Vfe (150kmh) - Power off - Opposite Rudder and Push, everything at the same time.... With a load of 11 Pax this would Situation would even develop a lot more Aggresive.
This Accident Looks a lot like a Flaps T/O Stall under Power, with the Exception that the Orginal AN would Spin to the Left.