Snap rolls?

Question

When doing a roll combined with full elevator (snap roll?) it obviously behaves a little differently depending on whether it was full-up or full down on the elevator but you still get the same general over-all effect. But what is the right way to do it? Is there a certain reason when you would do one over the other? I know that for a real pilot one produces positive G's while the other does negative G's,...but in a model, who cares ;-).

Anyway, I would just like to get the "short-and-skinny" on it.

John Miller · Accepted Answer

A snap roll is a one-turn horizontal spin.  When you do it with elevatordown, you get an inverted (horizontal) spin.  Your choice.

Paul Ryan · Answer

What you describe is not a snap roll-  a snap roll is like this: from level flight, give the plane full up abruptly and about a half second later give it full rudder.  To recover cleanly give opposite rudder, releasing the up elevator.   In my experience, most planes snap better to the left, since engine torque is helping the roll along.  Also, depending on how much rudder the plane has and where the c.g. is, you may have to work to get just the right entry speed and setup to get it to snap cleanly.  No aileron is needed.         -PaulPhillip W

Poxy · Answer

From my meagre understanding, a snap is based around using the elevator to stall the wing, which effectively stops flying, and using the rudder to initiate the roll, which gives a result quite different to an aileron roll. The latter will tend to be axial, whereas a snap roll will be driven from the tail and results in more of a tumble around the CG.

You can combine a snap with ailerons to get a mega-fast roll, but I'm not sure what it's called.

As for up or down stick, they're both snaps, although up stick tends to be more common.

Noah Little · Answer

> As for up or down stick, they're both snaps, although up stick tendsto be...and in the cockpit, they feel *much* different.

High Plains Thumper · Answer

Paul Ryan  wrote innews:6rgze.2636$     So then it's like a tight barrel roll?

John Miller · Answer

No, it is a horizontal spin, with one turn only.

fhhuber506771 · Answer

The effect of the aileron + elevator is a sort of a barrel roll... yes.

The "classic" barrel roll would have the aircraft exit pointed 90 deg t the line of entry. (which a WWI biplane would naturally want to do usin aileron+elevator for a sort of loop + turn

-- fhhuber50677

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CJ · Answer

As defined by the IAC (International Aerobatic Club)...

"Snap rolls also have to be flown normally on a straight line. A snap roll is similar to a horizontal spin. It is an autorotation with one wing stalled."

CJ

Malcolm Fisher · Answer

> View this thread:>You learn something every day.I thought a barrel roll was one in which the aircraft described a path asthough it was sort of spiralling round the inside of a barrel rather than anaxial roll in which the aircraft rotates round its longitudinal axis with nodeviation from a straight path.Malcolm

Noah Little · Answer

You thought correctly.

High Plains Thumper · Answer

John Miller  wrote in news:danaq5$prd$2Okay, gotcha.  BTW, does countersteering improve aerobatics?   ;-)

Snap rolls?

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