Original Posted By: "Dick Navratil"
Hi Pieters,Just reading everyone's comments regarding spinning. I have to say that I agree with Doc & Jim Ash.My profession is performing major repairs to damaged sailplanes and subsequent test flying through the aircrafts normal flight envelope.I have also worked as a full time,professional gliding instructor in Australia and taught both basic flight and aerobatics (gliders).I taught allot of people how to both get into and out of spins.I whole heartedly agree that pilots should not attempt spins without first doing formal training with a qualified instructor who is comfortable with spin training. (I know of instructors who themselves are not comfortable spinning).I feel that studying and fully understanding the theory of exactly what is happening to the aircraft prior to, during the incipient phase, during the fully developed spin and finally how to apply the correct recovery technique is vitally important to successful spin training.Spins should not be feared, they are just the result of a series of actions to which the aircraft responds. Once understood and practiced, they are both a fun and safe maneuver..........if the aircraft is loaded ( Cof G within it's limit's) and the pilot is fully trained to handle the maneuver.I agree that even in certified aircraft, small variations can turn an aircraft with normally docile spin characteristics into one that wants to do nasty things. An example is a training sailplane which was normally excellent for spin training had 3lb wing tip skids attached to each tip. With the 3lb skids sitting on the end of 18meter long wings, the rotational forces increased such that the aircraft used approximately 4000ft to recover from a fully developed test spin. ( the C/G was well within it's limits). The skids were removed (ie; back to the factory configuration ) and the test was performed by the same pilot/loading conditions on the same day and the aircraft was immediately back to it's normal 1/2 rotation to stop the spin then recover from the resultant dive.I feel that the spin testing of a new aircraft for the first time should be approached very slowly and carefully. Obviously, a pilot with ample experience in spinning, wearing a chute, and with lot's of altitude should perform the testing.The following would be my version of testing, anyone is welcome to disagree and it is not meant to overide proper training etc.First, basic straight ahead stalls should be fully explored in varying C/G positions.(all with the limit's of course)Secondly, if basic stall testing is successful with no nasty surprises, then the 'Incipient phase' (ie; stall with wing drop to a max of 1/2 a rotation & recovery) could be explored, once again with varying C/G positions. (still the limit's of course!!)Lastly, and only after the aircraft has proven itself safe in the last two phases, should the full spin be allowed to develop.I would perhaps try one turn then recover, and if successful, climb and try one turn in the opposite direction, recover and so on.The number of turns could be gradually increased to the number desired, testing in both directions...............step by step.An aircraft designer/engineer friend of mine in Australia, said that the fully developed spin can take anything up to 17 turns (yep, 17 turns!!) to 'stabilize' into a state of equilibrium, where the relevant forces involved are balanced.I have no idea if this is correct or not but I have never performed a 17 turn spin to find out !I fully agree that ANYONE can get into an unintentional spin, and when it happens in the pattern at low altitude, especially on the final turn, you need to get the recovery right the first time and do it with a reflexed action..........if not, it may very well be the final turn.If testing the spin characteristics of a new aircraft, understanding exactly what is happening may just get you out of a bind if things don't quite go smoothly.In gliding in Australia, spin training is not an option prior to solo flight, it is mandatory. However, during spin training, we emphasize the "understanding and recognition" of the events that occur PRIOR to the actual spin occurring. By becoming aware of the symptoms prior to the actual event, pilots are able to correct the situation before it develops into a potentially dangerous situation.This was only going to be a short note stating my agreence with Doc & Jim, I apologize for dragging it out but I love safety in flight. My ideas above should not be used as a substitute for actual hands on experience with a suitable qualified instructor, So, go and do the training, and enjoy your flying even more comfortable in the knowledge that you have a good chance to save your bacon should the little thing called a spin occur to you sometime!!Safe flying to all.RegardsMark SJapan...........still hot & sweaty!________________________________________________________________________________