Originally Posted by Gipsy Queen
Spins are great fun and the aircraft performs these well (with/without spin strakes) but as has been mentioned above, the number of turns should be limited. I never did more than four. After that the attitude flattens (upright and inverted) and when the Chippie goes flat, it stays that way. No recovery. Keep the CG as far forward as possible (full tanks help) and if you have a passenger who fancies some aeros - and if he doesn't, don't bother to take him up - stick him in the front if he is substantially heavier than you.
The RAF AP101B (pilots flying notes for the Chippy) states,
'After prolonged spinning (six to eight turns) a heavier push force may be necessary to effect recovery. In a stable spin, particularly when the rear seat is occupied, the aircraft may continue rotating for up to three turns after taking recovery action. During this period, the rate of rotation increases and the angle steepens before the spin stops. If the aircraft is slow to recover from the spin, the application of aileron in the direction of the roll assists normal recovery action.'
I have done lots of 8 turn spins (8 being the limit in RAF service) and never really noticed a tendancy for the spin to go flat and never had to use the delayed recovery technique. The book is correct though, when it says that delay is increased after 8 turns.
And as for the C of G, the limits are 6.48" forward to .257" aft of the datum. How do you measure that? Don't know, but suffice to say that we never checked the C of G on a daily basis. The limits were so broad there was never a problem with any combination of fat or thin crews. There was a difference in handling with different crews though. I have been known to enjoy a pint or two in my time and when I was flying the Chippy as an instructor, I weighed 95kg. One of my students could have done with a good meal and weighed no more than 50kg. This didn't affect the handling to any unacceptable degree, but the Chippy cetainly spun well with us on board!
The spin entry technique we used in the RAF was done from 50knts. At 50, full rudder was applied and the control colum was moved fully back. This led to a clean entry with a stable spin resulting. However, if the wing dropped at the fully developed stall and you applied full opposite aileron, the Chippy could enter a slow and flat - but very stable spin from which the recovery took about three turns.