Weird JF PA28 stall behavior.

[mikegrr 109]

So I experimented  with various stalls in the PA28. First,  I tried an accelerated stall by pulling hard on the yoke with power on. The plane stalls and drops a wing, but there is no stall warning. However if I set the trim up, there is an audible stall warning. Can this be right? Then I tried a power off stall. Gear down, I pull hard on the yoke...The plane sinks, but never actually stalls and no stall warning and the plane maintains about ~ 60 kts or so in a ~ 1000 fpm descent. I think if put in lots of up trim, then there is a stall warning.

How is this supposed to work? What triggers the stall horn to go off?

I'm trying this as I get no stall warning when landing...the plane just drops onto the runway.

Edited March 20, 2021 by mikegrr

[Chock 17,769]

45 minutes ago, mikegrr said:

How is this supposed to work? What triggers the stall horn to go off?

Stall warning horns all pretty much work the same way. There's a detection tab on the wing which is functionally a similar concept to a pitot tube, a tab mechanism in a hole has a small spring-loaded switch which is held open by the normal air pressure going over the wing when it is at flying speed. When the airflow disrupts to the level of pressure that is akin to a speed about ten knots above the stall, that's not enough to hold the switch open, so it closes and that triggers the stall warning. The stall vane is the little metal tab sticking out of the plate with six screws fixed to the leading edge, on this picture:

On modern aeroplanes, when the switch triggers, the sound is electronic (this is the type on the PA-28), on older aeroplanes from many years ago (if they had such a device at all) it was literally a reed similar to that found in woodwind instruments which would sound from the air going over it when it becomes exposed to the airflow, it being designed to make a sound at a certain low airspeed.

Theoretically you should be able to fly along slowly with it permanently sounding at just above the stall speed. They are known to jam on occasion since they are exposed to dirt, but can easily be cleaned out by dismantling them and soaking them in cleaning fluid. Really there's only two things which could make them not function, since it is a very simple mechanism; one would be a loose electrical contact, the other would be some dirt preventing the thing from either moving or closing its contacts to send an electrical signal to sound the horn. I doubt if any of those maintenance issues are simulated by either Just Flight or MSFS, but there is the possibility, if you have the wear and tear selected on your sim, that this might be glitching the system, since it simulates dirt on the airframe reducing the airspeed.

 

Edited March 20, 2021 by Chock

[sd_flyer 6,042]

I haven’t tried airworthy in JF after the patch. I have noticed they modeled trim stall kind of odd way before patch. 
Any way approach stall ska power off stall  you want to establish slow flight  in landing config (gear, full flaps down ) . Keep +5kts above stall horn . Trim for airspeed . Then bring power to idle descent 500 rpm for 3 seconds and then bring yoke all away aft until airplane get to critical angle of attack and nose drops . 
Im not sure what “hard” means fast or all the way aft? But sound like in your case airplane not really stalling but rather descending. I think there is no elevator authority to reach stall that why when you trim you get extra boost to reach alpha 

Edited March 20, 2021 by sd_flyer

[SAS443 1,723]

What OP describes happens to me all too often. Seems like I run out of elevator (or "stabilator" rather) authority and plane settles on a 1000fpm descent and refuses to stall. Only if I trim full aft am I close to achieving any resemblance of a stall situation.

[Glenn Fitzpatrick 3,798]

If your testing things like this you probably should revert your elevator sensitivity to linear with no dead zones just for test.

[Nickbe 401]

Hi all!

There is a good video from the RL pilot instructor about this Piper Arrow. At the 50-minute mark, there is a stall test. Before watching this video, I assumed that the implementation of stalling is not entirely realistic. Now I've changed my mind.

 

 

[mikegrr 109]

I am using linear joystick settings. 
My point is that the stall warning only works with a lot of up trim. If the trim is neutral, the stall warning does not go off and the plane quietly descends. I don’t believe this is the way it actually works, but I don’t know that for sure. 
When I am landing I usually have the plane in neutral trim so I never hear the stall horn. Seems wrong to me. 

[sd_flyer 6,042]

IRL stall horn is just stall horn. I flown many airplanes with stall horn into. Also there are some older planes that don’t even have audible stall horn - just a light . 
Most GA airplanes designed not to have dramatic stalls. Arrow is not an exception .
 

Now if we talk about T-6, fist time I stalled it I ended up inverted LOL Guess why? Not enough right rudder LOL

[Chock 17,769]

54 minutes ago, sd_flyer said:

Most GA airplanes designed not to have dramatic stalls. Arrow is not an exception

Yup true. The PA-28 was designed with the training market in mind, but it was also designed with the notion that it would be nice and stable as well.

First time I ever tried to spin an aeroplane it took me about three goes before it would do anything other than just mush along. I remember thinking I must be a bit of a cack pilot if I can't even get it to spin lol. So I really hoofed the rudder as I pulled up an off it went, dropping like a stone and rolling to the right as it went. 🤣