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The better BRS are fully deployed in 3 seconds and are shot well clear of the plane to avoid tangles. Believe it or not they can be deployed down to 30 meters ( 100 feet ).

 

I wouldn't recommend that. Having worn a pilot chute for many years I know it is very hard to exit a plane in an unusual attitude.

 

John.

 

 

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When Harry Schneider was doing certification testing on a new glider, he had to demonstrate spin recovery at a c of g even further aft than the allowable limit. I remember he used a bag of sand with a cord to spill the sand out if the situation became dire. The sandbag was fixed to the rear fuselage.

 

So I find it surprising that a certified aircraft , flown within allowable g of g , could have a dangerous spin.

 

 

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Since a spin is a non controlled occurrence. (the inputting of the controls doesn't directly have their normal effect,) I have always regarded spins with a certain amount of wariness about just what will happen when (and I've done a lot). Treat them as not fully predictable, and have an "if all else fails" procedure in your bag of possibles. Nev

 

 

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ABC is reporting a plane crash in Victoria.Plane crashes at Black Range in Victoria's west

Tecnam vs Bristel. With these aircraft, the tail seems forward of the horisontal stabiliser, having a swept horisontal stabiliser would also contribute to blocking airflow to the movable tail. Also, I suspect that the more ambitious someone was about the performance of their aircraft, the closer the stall speed of the horisonatal stabiliser would be to the stall speed fo the main wing. 60 degrees *might* be a bit arbitrary for the angle, but the difference in the amount of the exposed control surface is massive. Just, wow. bristel.jpg.e091873eba340ea97a8d6ca37b8e6145.jpg

 

tecnam.jpg.91056418947a7c421b1a96cf93049663.jpg

 

 

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This is taken from Darrol Stinton's book "The Design of the Aeroplane" which might be of relevance or interest. Furthermore Stinton notes that spin damping is better when there is a deep rear fuselage and when there is rudder area beneath the tailplane and elevator. None of these are designed into many modern aircraft including the above as so many LSA type aircraft become very thin towards the real fuselage including this aircraft. Interestingly Stinton (perhaps controversially) writes in relation to the above quote "much of this design wisdom is being lost".[ATTACH=full]62068[/ATTACH]

Too, the Tecnam has more fuselage below the horisontal stabilizer.

 

 

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These aspects are good general rule of thumb considerations and general GOOD ADVICE.. The shielding of the rudder IS a problem. Why the rudders slope is perhaps a silly styling exercise that should put you off buying it if you had the option. Plenty of FAR 23 info about that's in the same vein. Why not learn by other's misfortunes? You don't live long enough to work it all out again for yourself. There's a few crap designs out there and more appearing all the time. OK as a desk top model? Not even that. Nev

 

 

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Too, the Tecnam has more fuselage below the horisontal stabilizer.

The Tecnam also flys much nicer than the Bristell in my bias opinion, having flown a Bristell I would have my low wing Tecnam any day of the week.

 

 

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I wouldn't say Mooney have it particularly right though I'm not saying it has an evidenced problem. A 60 degree line from the leading edge still eliminates a lot of the rudder area. Some rudder under the horizontal stab helps too when it's there.. The strake in front of the fin helps to make the rudder more effective as well as a rounded fuselage section.. Nev

 

 

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Still need enough out of the "blanketed" area - easy enough to do a reasonable assessment at the initial design phase but costly to fix at prototype stage. Even just to demonstrate compliance with the LSA requirements for recovery from a one turn spin is a significant and costly effort.

 

162designchanges.png.ecf64c08b9c5ecc539e24df53585cb2f.png

 

 

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