Sorry for this long response but I am passionate about this issue and some clarifications are necessary.
It is only true that most spins can be prevented if 1.5Vs is maintained. A mishandled entry of more than 1 "G" steady is possible at much higher speeds. (E.g. Mishandling and Snap rolls) Many things lead up to the inadvertent spin accident. Having reached autorotation, only a successful spin recovery can save the final accident chain outcome. We must mitigate against this identified risk. Obviously, safe speed near the ground training is not working all the time and only gives the training department a false sense of security in their job of preparing a safe pilot. We all perform this monkey do action for the instructor and yet we still have spin accidents. The fact is that all pilots can make mistakes when loaded up in a circuit and our best laid plan is falling apart. This stress can and has resulted in slower than intended speeds. The majority of spin accident result from too slow/high angle of attack flight. When everything else has failed, it is the ability to recover from; 1. Slow flight 2. Stall, 3. Incipient spin, and finaly 4. Spin that may save the day. I certainly wouldn’t give up on a full spin recovery well below 1000ft AGL! An incipient spin recovery on final should still result in a controlled landing. And every one of us has recognised inadvertent slow flight on short final and done something about it to avoid the heavy landing. Instructors see this one every day. We need more low speed, high angle of attack flying training; not less. A yearly check in a training ACFT by an instructor under pressure to accept the minimum requirement, with the average pilot, no longer current and now in another type, 12 months later, who has inadvertently allowed his IAS to decrease below some nominated speed is an accident chain. If progressed to this stage, then the final outcome will only be saved by knowing how to identify high angle of attack flight and a speedy recovery. With regard to the “slippery” training ACFT not providing realistic anti spin training. It is the instructor who makes the over-riding difference but even then, one should not blame the tools he has to work with. I also note the high drag/low drag and the money savings/pilot satisfaction arguments. I address the high drag verses low drag argument as it applies to the ACFT I'm familair with, having read their Flight Manuals. I use the techniques personally taught me and described in AG by Mike Valentine and the GFA Instructors Manual and I do have aerobatic endorsements. I mention this because I want to stress that the aerodynamic/gyroscopic/CofG characteristics of the preferred types mentioned are consistant when using Mike's technique. I know that the DG1000 can be recovered with the same or less height loss as the Puchacz and both of these take a little more than the older L13 and the L23. This is directly related to the type of *autorotation* entry/recovery characteristics of the types, not the pull out from the ensuring dive. The Blaniks take just a little over 90 degrees of turn to recover from the autorotation. I have also extensively checked the spin entry and recovery characteristics of the ASK21 with its required spin kit fitted. Suffice to say no instructor willingly uses the ASK21 for spin awareness training at Beverley. Other clubs may have no other choice. The full spin recovery is designed to minimise the height loss once a spin has been allowed to develop. A major part of height conservation is gained by correctly identifying when the ACFT has recovered from the autorotation phase and we can therefore re-apply back stick but importantly play “G” against airspeed. Amazingly, in the majority of cases on all types, this is the area where most will lose excessive height; just when the ACFT is under their complete control! The problem is one of identification and this can only be improved by determined training and greater currency; not less. It is not ACFT specific and it is a cop out to propose one ACFT is worse than another. The instructor needs to become current with all his ACFT and teach minimum height loss with that particular tool. After all, it is a club ACFT and will be flown be a wide cross section of club members, all of whom form an accident chain sooner or later. The DG1000 autorotation recovery is both predictable and quick at all pilot weight combinations because of the ingenious and quick tail ballasting facility allowing a generous CofG range for spin training, even with the GFA 5% reduction over the Flight Manual range. The following pull-out phase, due to the initial lower zero “G” drag and subsequent increasing “G” lower drag during pull out provides a higher acceleration meaning less time to achieve safe flying recovery speed and therefore less height loss in this fully aerobatic ACFT. One should be achieving a recovery speed maximum of 65-70IAS on this type or redoing the exercise before sign off. I would need to check my flight logger but expect two full spins before initiating recovery to take less than 1000ft from entry height to lowest part of recovery height before recovering much of this height loss when back at 1.5Vs again. In any case, I get the same number of training exercises in the DG1000 as I did with the older L13/L23 and like those earlier ACFT, the DG1000 is always spin training ready for all flights; an important factor if we are to truly keep our pilots current. -- Kind regards Daryl Mackay
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