floridagc@aol.com (Florida GC) wrote:
>I just experienced my favorite manuver yesterday. I was out with my
>instructor and he told me he was going to demo a tourqe turn. For those
>of you who don't know what that is, I'll explain. At 500' AGL and 75 kts.
>you pull full aft cyclic, climbing fully vertical. at the apex of your
>climb, pull full collective pitch and the fuselage will torque 180 degrees
>to the right, sending you nose first, straight to the ground. Slowly pull
>aft cyclic to regain straight and level flight. No roller coaster ride
>will do anything for you after one of those. I tasted my english muffin
>at 2:30 in the afternoon.

[Full aft cyclic and full collective sound rather extreme. Paul's description sounds much more reasonable.]

BTW, I first started doing these when I guy I knew who did AG flying showed it to me. It's a way to make passes up and down a field spraying without having to have your feet on the pedals. The way I was shown, and do them myself, is to not use any extra collective during the turn. Bring the nose up to bleed off airspeed, as the airspeed decays, torque will yaw you without any extra collective. As the aircraft continues to yaw, allow the nose to drop and gain airspeed, then use aft cyclic to level out over the ground as you begin your next pass.

The higher you raise the nose, the faster the yaw will snap you around, to the point of being quite frightening. If you do it with less nose up attitude, the yaw will be slow and very comfortable. Neither the pedals or the collective are being used during this: it's all cyclic work (and not much of that). It's a very relaxing way to make 180 degree turns.

Paul Cantrell

==========
From: John R. Johnson (john@siu.edu)
Subject: Re: One More Time! What are your favorite maneuvers? (Helicopter)
Newsgroups: rec.aviation.rotorcraft
Date: 1996/01/08

actually the "ag turn" in a helicopter bears the same relationship to a hammerhead, that the "ag turn" in an airplane bears to the hammerhead. In a hammerhead you go straight up until your velocity reaches approximately zero. Then you spin about your yaw axis and proceed straight down until you attain flying speed again, then recover to level flight.

In an "ag turn" you pull up to reduce speed and turning radius. In a helicopter the reduced speed caused by the pullup causes a torque reaction that, uncompensated with the tail rotor, causes the helicopter to spin about its yaw axis, whereupon you descend to level flight, regaining the airspeed you gave up in the pullup.

In an airplane, the "ag turn" is done by pulling up to reduce speed and the resultant turning radius, and then executing a wingover type turn of minimum radius followed by a shallow dive back to working altitude and airspeed.

In both cases the "ag turn" is a relatively gentle maneuver that is quite controllable and safe at low altitudes when properly performed. No undue loading or UNloading it put on the aircraft and a 180 degree turn is made in minimal time with no altitude loss. The minimal time is important for an ag pilot cause you ain't making no money while you are turning!

John