DG does reverse 360s

timwinters

timwinters

Ejection Handle Pulled
Joined
Feb 23, 2008
Messages
13,733
Location
Conway, MO
Display Name
Display name:
LTD
This was an interesting experience.

About a month ago I was out playing and doing upper air work; steep turns, slow flight, stalls, Immelmanns, lazy 8s, etc.

When...

About a 1/3 of the way thru a 60* steep turn the DG does a reverse 360*.

It really f***ed with my head the first time it did it...seeing it rapidly spinning out of the corner of my eye was pretty bizarre. I immediately rolled into an opposite direction turn and, yep, it did it again.

So I did a couple of 45* turns and it was fine.

I've been up playing a couple of times since and it continues to perform its aerobatics on every 60* turn. Never on 45s.

Guess it's time for an OH or replacement...

Oh, and when it's all said and done, it still indicates the proper heading.
 
Last edited:
Immelmanns? What plane are you flying?
 
Oh, you probably mean a stall turn, not a half loop and half roll like I was picturing.
 
The earth's poles are in flux right now, and about to do the big flip.
(and you must have a magnetically slaved DG.)
 
There are tilt limit stops in the DGs I've seen apart. 60° sounds about right. Once the gyro case hits the stop, the airplane's yaw causes massive gyroscopic precession that spins that DG like that. I've seen it in spins, too. If the DG works OK the rest of the time there's probably nothing wrong with it.
 
I can't imagine it is good for it.
The big, old AIs used to have a caging knob that we locked before doing spins.
 
You must log in or register to reply here.
Back
Top