RE: Tip Stall
 

Excellent thread and I hope more people read it!

RE: Tip Stall
 

It all depends on the angle of thrust. One can make a "level turn" at 90 degress bank with enough up thrust. And depending on how hard you pull the elevator you can get a 2G turn or a 9G turn.

It's all about the forces on the aircraft - ALL OF THEM.

RE: Tip Stall
 

There is quite a story about the ultimately simple appearing solution to the problem of one wing stalling during approach with the F-4U Corsair.

Jess

RE: Tip Stall
 

Hi Gerryndennis,
I wasn't replying to you so much as just adding what I know (or think I know) to the thread. It's a very interesting topic. Thanks for your reply, it goes to show how little I know.
Cheers.

RE: Tip Stall
 

Could someone tell me how to tell the difference between an asymmetric stall and a tip stall. What are the visible differences.

RE: Tip Stall
 

In an asymmetric stall (stall developing from the root) the wing will drop and a spin may develop if no correction is made.

In an asymmetric stall (stall developing from the tip) the wing will drop and a spin may develop if no correction is made... much more violently and quickly.

In an asymmetric stall (stall developing from the root) aileron (gentle) will at least reduce the roll and may be sufficient to prevent the wing drop.

In an asymmetric stall (stall developing from the tip) aileron will make the wing drop worse.... much worse.

Flymad you're post said 'in reply to... me' in the bottom right hand corner, which is why I wondered.

Dave H

RE: Tip Stall
 

Well I've never been accused of being wise in here before, usually when I post something that doesn't match the accepted wisdom I get ignored, so thank you. And yes to both, you? RAAF?

I agree totally with your 'elevator is a (the?) angle of attack control device' concept but I wasn't allowed to call it the 'joy stick'. Sort of a 'this is my rifle, this is my gun, this is for shooting, this is for fun' argument for using correct terminology (military's funny like that).

My first flight with a civilian instructor included 30 minutes of basic stall instruction as part of the type rating (light twin) and then a demo of the recovery. When it was my turn I checked forward, increased power, and climbed away. 'What the hell was that' he yelled 'you'll re stall if you recover like that, you need to go for speed'.

I pointed out that if speed was the important thing then what was the point of the last 20 minutes (that I was paying for) demonstrating all the (angle of attack related) stall symptoms. And how would his recovery work at 300' turning finals from a circling approach, you guessed it his speed based recovery took 300', mine 30' (yeah I know but it was my first touch of the stick, sorry sir, control wheel).

To give him his due he did accept that he had been teaching it all wrong, especially after I showed him some accelerated stall recoveries (2G /60 bank, 90 bank and about 30 kts in a wing over). Doubt that he's been able to convince CAA to change the syllabus though.

Where do you teach aero's?

Dave H

RE: Tip Stall
 

Nothing "makes" one maintain level flight. OTOH, should one (pilot) decide to maintain level flight then that someone has to follow the laws of nature such as lift equal to weight.
To produce lift in subsonic convergence airflow, one has to provide the airflow with needed pressure variations to attain the needed forces. Given a wing in a 60° bank relative to earth, at I G loading will be 1 G short of the required aerodynamic force required to maintain level flight.

Should you not understand these basic lift/drag/etc. aerodynamic truths, I certainly agree that you would have absolutely NO IDEA of what I was/am saying.

RE: Tip Stall
 

Don't disagree. But if you had read before you pounced you would have seen my comment that Iwas practicing low powder flight to see what it would do beforeand afterentering a stall. Most models don' t come with a pilots operating handbook behind the seat stating the stall speed so you have to find out emperically. To do that you reduce throttle and maintain altitude with elevator. This isn't my first rodeo, either.

RE: Tip Stall
 

This is why I preach so much about the greatness of light weight airframes, the lower the wing loading is, the less one must worry about those nasty tip stalls, on the stuff I build and fly for the most part there is no tip stall characteristics to think about at all; so I am left to just play and have fun, but many times when ever I fly somebody else’s airplane especially warbirds; I must manage my available energy throughout the flight envelope to keep things on the ball. For this very reason I believe warbird pilots are better pilots than most 3D pilots, warbird guys deal with these issues due to higher wing loadings all the time, and the ones that don't manage the energy very well... Crash and burn.

Bob

RE: Tip Stall
 

After fooling about with aviation for some time now. Full scale and flying models. I have never encountered a beginner wanting to know all the ins and outs of aero dynamics. Most new folks, also known as beginners know if the tip of the wing hits the big ball, also know as the earth, it is a bad thing. Now I do think the beginners that come to this section of RCU do enjoy all this going ons about what make one of these things fly. What I have found out is some pilots are better flyer because of the planes they fly. I also discovered who is the best pilots depends on who is doing the telling. Like one of the new dudes told me yesterday on the flight line. "Mr Jerry, some of these people are real serious about all this"

RE: Tip Stall
 

Serious? Did you ever go to an RC show where everythign is there? Watch closely at the RC Tank folks. Now that's serious.. almost scary!! [X(]:D