Stalls

[RFguy]

Flying has got me thinking about more of this.

I have several questions. one by one :

 

if in level flight ,wings stalled , homogenous clean air, NO propeller, no aileron inputs, plane in balance on the longitudinal axis , both wings should drop in synchronicity , right ?

 

So my question is, the wing drop , typically port wing , due to a lack of ability for the wings (producing lift) to resist the engine propeller torque ? IE if there was to torque, (no engine running, no prop present), then there would be no torque to twisted the aircraft into a wing drop. ???? IE wings in stall = no wings (limiting case) and so no resistance to prevent aircraft rotating around the prop ?

or is it just pot luck to what the air is doing, and which wing loses what lift it had first ???

 

glen

[spacesailor]

depends on the particular plane, Also if the right-hand seat is occupied !.

Big jet liner's have little or no torque, so do drop vertically down .

just saying this for the Fun of stall practising that I like.

spacesailor

[Jase T]

There are about elventenine billion variables ranging from which wing has more fuel in it to what seat the fat guy is sitting in even one tiny bubble of air that is 1 degree hotter than the surroundings. It's easier to say pick up the wing with rudder, unstall the wing and do what the POH says...

[Downunder]

Wind direction....

[Thruster88]

There are about elventenine billion variables ranging from which wing has more fuel in it to what seat the fat guy is sitting in even one tiny bubble of air that is 1 degree hotter than the surroundings. It's easier to say pick up the wing with rudder, unstall the wing and do what the POH says...

Picking up the wing with rudder can lead to a spin in the other direction. The rudder should only be used to prevent yaw at the stall, no yaw no spin. Having said that an INTENTIONAL falling leaf maneuver with the stick held full back is a lot of fun in a thruster.

Wind direction....

.?...????

[Roundsounds]

It's easier to say pick up the wing with rudder, unstall the wing and do what the POH says...

You should not pick the wing up with rudder when stalled. Rudder should only be used to prevent further yaw in the event of a wing drop in a stall, the wing is “picked up” after stall recovery.

[facthunter]

Any little thing will make one wing go before the other. Once that happens the effect immediately becomes more exaggerated. Don't use aileron to try to lift the dropped wing or it gets worse. Keep stick position central till unstalled. Pulling the stick back to stop the nose falling away sets it up for spin entry. This is usually an automatic response till you educate yourself out of it. Nose down and/or power will increase speed. Power is not needed or helpful, if you are looking straight at the ground. You KNOW you are going to do a stall at the present time, but the one that kills you won't be anticipated and you will probably be in a turn anyhow when you "accidently" get stalled.. Nev

[spacesailor]

OR

Get a Canard ,.

spacesailor

[Jase T]

You should not pick the wing up with rudder when stalled. Rudder should only be used to prevent further yaw in the event of a wing drop in a stall, the wing is “picked up” after stall recovery.

 

You are of course correct sir. My phrasing was a little old (that’s actually what I was taught) and also incorrect. The picking up was a concurrent activity with the breaking of the stall due to lowering of the AOA. This was done during spin training.

[facthunter]

Wing stalling is an ANGLE of ATTACK issue and what actual airspeed you are doing at the time may vary widely, in the real world.

Your airplanes ACTUAL stall speed is reached under varied normal and dynamic load conditions .For certification it is at max wt and most forward Cof G allowed and in a stable unaccelerated state (1 "G" load) Power off.

The angle of attack is to the RELATIVE airflow ,not the horizon or any such visual reference and the "THING" that controls wing AoA is the elevators and who control's them? YOU. . In most stall related incidents the pilot CAUSES the stall by the way He/She operates often instinctively rather than appropriately..

Any time your BUM is light in the seat the wing has to provide LESS lift so the stall reading is lower. Conversely when you are heavier like when recovering from a dive, or doing a steep turn and you are pressed into the seat the stall figure is increased (Higher) as the wing has to provide more lift..

Most of the "standard" stalling training exercises are close to useless as it's usually just a bleed speed hold altitude PRESCRIBED thing where in practice you would rarely if ever stall unless you left the autopilot on ALT hold and closed the throttle .Nev

Edited September 7, 2020 by facthunter

[kgwilson]

I have a BFR coming up so today I thought I'd do some stalls as I don't normally bother except when doing a BFR. I have no idea why they want you to stall at x thousand feet. I stall the aircraft every flight when I land so why not just accept that. My aircraft is one that just mushes anyway & with the ASI indicating about 20 knots I was just parachuting at about 300 fpm.

[RFguy]

I think there is confusion in some people in landing --my understanding is that the aerofoil is not going to stall at a low AoA and low forward air speed BUT negligible descent rate- like floating along the runway - you are just going to sink due to lift being proportional to V^2, but its not technically a separated airflow (stall at critical AoA) because the relative airflow is at a low AoA. . However! A high vertical descent rate relative to the forward airflow will produce a proportionally high AoA, (due to relative airflow angle) and can that can be a stall. Is my understanding correct ?

 

as the stick is pulled back you are playing up the AoA curve a bit and at some point the stall will occur rather harmlessly.

and I want to know what happens to the centre of lift location either side of the critical AoA.

[Blueadventures]

I think there is confusion in some people in landing --my understanding is that the aerofoil is not going to stall at a low AoA and low forward air speed BUT negligible descent rate- like floating along the runway - you are just going to sink due to lift being proportional to V^2, but its not technically a separated airflow (stall at critical AoA) because the relative airflow is at a low AoA. . However! A high vertical descent rate relative to the forward airflow will produce a proportionally high AoA, (due to relative airflow angle) and can that can be a stall. Is my understanding correct ?

 

as the stick is pulled back you are playing up the AoA curve a bit and at some point the stall will occur rather harmlessly.

and I want to know what happens to the centre of lift location either side of the critical AoA.

Ask your instructor about this one, and more important get him to take you through the situation at much height. IMHO. Cheers

[RFguy]

cheers.

today and yesterday's flying :

https://www.recreationalflying.com/threads/just-joined.72728/post-572178