Ground loop

try google
second result was: Ground loop (aviation) - Wikipedia, the free encyclopedia
they get quite wordy
in simple terms, ground loop = unintended 360 degree yaw at ground level
not a high difficulty maneuver with some planes, but it has a very high PF value

On Tue, 23 Oct 2007 08:39:56 -0500, Bob Cowell wrote in :
I wouldn't require a full 360 to call it a ground loop.
If it goes through 180 degrees, that's loopy enough for my taste.
Marty

"Martin X. Moleski, SJ" schreef in bericht news: snipped-for-privacy@news.supernews.com... Watch this

So is just an (unexpected) turn on grass.
F.

It's an abrupt turn on the ground, experienced with tailwheel-type airplanes because they are negatively stable in yaw. The principal weight is on the main gear which is ahead of the center of gravity, so if the airplane yaws a little to the left, its center of gravity is to the right of the center of the landing gear, and tries to turn it further. The more it turns, the more abrupt the turn becomes, and it usually puts the outboard wingtip on the ground if not worse.
Tricycle gear airplanes are positively stable in yaw -- any yaw will produce a tendency to turn the other way.
Keeping a taildragger straight on the ground takes a LOT of practice, which is one reason why you don't find many full-size ones available for rental.
rj

How old are you now, 11? :-)

That was the first maneuver I could do, but I was a lot older. :-)

Better known as "Welcome to the "Garden Club"....
Bill

More specifically, any yaw sends the wheels off in another direction, while the airplane's mass, centered at the cg and being behind the mains, wants to travel straight ahead. The two forces (wheels in a different direction than CG) produce a couple that aggravates the situation. It can get very expensive. In the 1950s manufacturers found a demand for tricycle airplanes because they didn't have that bad habit. So they built trikes, and at the same time they came up with a lot of other idiot-proofing devices like washout and even rudder/aileron interconnects, and piloting skills dropped accordingly. So did aircraft performance. We have the same problems with cars and drivers: Anti-skid brakes make it easy for a driver to just mash the pedal and trust the systems to keep him out of trouble. Until one day he gets into a situation that even the ABS can't fix, and there's a mighty crunch. All because he never developed a respect for road conditions and vehicle limitations. Today, learning to fly in a taildragger will make a much better trike pilot. His precision is far better. I know this, as an FS flight instructor on both trikes and taildraggers.
Dan

Good points, But,,, I object to the term idiot-proofing,
After 50+ years of dealing with farmers, truck drivers, factory workers, factory maintenance people, etc,,,
I can assure you that NOTHING is idiot proof, "idiot-resistant" is the best we have been able to manage
bob

Haven't you heard the old saying? As soon as you make something idiot proof, they'll invent a better idiot.

Actually, I was going to have that engraved on the back of my watch,,, BUT "Illegitimi non carborundum" was cheaper and fit better ;-)

I always liked the phrase "Nothing is foolproof because fools are so ingenious."