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Thread: Spin Recovery
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Old 21st Aug 2007, 05:44
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ithinkso
 
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this is an interesting thread.

i was looking back at the c150/c152 recovery techniques.

in a fully developed spin a c150 will not recover by itself. a fully developed spin in a c150 is a difficult thing to achieve. this is due to the genius design of the engineers at cessna.

for a spin to be fully developed it must continue to spin without any control input by the pilot. if control inputs are required the aircraft is not in a fully developed spin, only a DEVELOPING spin.

the c150 will not enter a fully developed spin unless it is induced by the pilot. because of the genius of its design(idiot proofing), the c150 will recover from a developing spin if the pilot releases the flight controls. regardless of the nunmber of rotations the aircraft has completed, if the pilot is required to hold control inputs to keep the aircraft turning, the aircraft is not in a fully developed spin, only a developing spin.

to induce a fully developed spin a c150, full aileron in the direction of the spin must be used. trickle of power, slow speed reduction, just prior to the point of stall, full back stick, full rudder in the desired spin direction, AND full aileron in the desired spin direction. AND then you must hold it. after a number of rolls, the aircraft will settle into a developing spin with an increasing rate of rotation. the control inputs are still being held at full deflection. the aircraft will then pitch nose up and the rate of rotation will reduce markedly. at this point, all the flight controls will will remain in the position where they were positioned by the pilot to induce the manuovere. even when they are released. ie: full back stick, full rudder, and full aileron. it can be very disconcerting to a pilot who has not experienced that before.

centralising all the controls will not cause the aircraft to recover. the g loads and low rotation rate are all very comfortable. this is the dangerous part. the aircrafts rate of descent is well and truly beyond the limit of most GA vsi's.

the only way to recover is with controls fully centred, apply full and brisk nose forward elevator. and hold it. if this does not work within 2 or 3 rotations, you can try applying power in conjunction with the nose down elevator. the problem is this, you risk flattenning the spin further. also it is not uncommon for the engine to stop in this manouvere. application of full opposite rudder will actually increase the rate of rotation. bizarre but true.

this manouvere takes thousands of feet to conduct. it should not be attempted by persons who have not been trained for it. this includes instructors who have not been trained to do it properly. as i read previously, yes the little baby can bite, but like a placid dog, it has to be severely provoked.

this is not how we taught students to spin the aircraft. it was taught in the same benign way as it is still being taught. most students find the developing spin scary enough without being shown that beasty is quite capable of injuring them. the advanced and fully developed manouvere was taught to instructors who would be teaching spinning and aerobatics.

bear in mind, this was 25 years ago, when the aircraft were new. i dont know if i would want to be doing these sort of things in aircraft that are now 25-30 years old, the entry to the manouvere can be quite stressful.

anyway, just musings from an old fart.

Last edited by ithinkso; 21st Aug 2007 at 06:42.
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