Minimum height for practice stall recovery in C172
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Well, ok LeadSled. I'm slightly dubious, but you may well be right about the statistics; I have no statistical analysis to back me up.
However, the Air Safety Foundation, as quoted by AOPA, do seem to support the FAA in rejecting mandatory spin training for powered flight licenses. I accept that gliding is & should be a different case, due to the different aerodynamics and prolonged time spent manoeuvring close to the stall.
Bringing this back onto thread, at what height do glider pilots practise stalling? For training that is, not for experienced pilots having fun.
However, the Air Safety Foundation, as quoted by AOPA, do seem to support the FAA in rejecting mandatory spin training for powered flight licenses. I accept that gliding is & should be a different case, due to the different aerodynamics and prolonged time spent manoeuvring close to the stall.
Fatal stall/spin accidents most often begin at or below traffic pattern altitude... From that altitude, even pilots with aerobatic training stand virtually no chance of recovery. Spin training for private pilots ... appears to be of little benefit in reducing the incidence of stall/spin accidents... Stall/spin accidents, many in training, have declined dramatically since the elimination in 1949 of mandatory spin training for private pilots.
Last edited by Oktas8; 9th Dec 2013 at 21:14. Reason: Spin height comment
Bringing this back onto thread, at what height do glider pilots practise stalling?
You cannot compare the spinning characteristics of a Blanik versus a Traumahawk (or a C172) - they are worlds apart.
Yep, I have lots of rotations in both.
Dr
Glider Regulations re Aeobatics
From the Gliding Federation of Australia (GFA)
Manual of Standard Procedures, Part 2 – Operations December 2012
Page 11
8.1.10 Aerobatics
Before engaging in aerobatic manoeuvres the pilot in command of a sailplane shall ensure that:
(a) The proposed manoeuvres are permitted by the sailplane's Certificate of Airworthiness;
(b) All occupants of the sailplane are secured with correctly-adjusted safety harnesses;
(c) The safety harness of any unoccupied seat is made secure so that it does not foul any controls of the sailplane;
(d) All loose articles are removed from the sailplane or made secure in the sailplane; and
(e) The proposed manoeuvres will not bring the sailplane into close proximity with other aircraft (CAR 155(4)).
The GFA pre-aerobatic check is at Appendix 1.
Pre Aerobatic Check
page 61
PRE AEROBATIC CHECK HEIGHT – Sufficient for recovery by 1,000ft AGL.
AIRFRAME – Flaps, airbrakes, undercarriage set as required. Trim as required. Hatches and vents closed and locked as appropriate.
SECURITY – Harness secure. Loose objects stowed.
LOCATION – Clear of built-up areas, cloud, controlled airspace.
LOOKOUT – 180o plus 90o turns checking carefully around, above and underneath. Do not do a 360o turn.
Manual of Standard Procedures, Part 2 – Operations December 2012
Page 11
8.1.10 Aerobatics
Before engaging in aerobatic manoeuvres the pilot in command of a sailplane shall ensure that:
(a) The proposed manoeuvres are permitted by the sailplane's Certificate of Airworthiness;
(b) All occupants of the sailplane are secured with correctly-adjusted safety harnesses;
(c) The safety harness of any unoccupied seat is made secure so that it does not foul any controls of the sailplane;
(d) All loose articles are removed from the sailplane or made secure in the sailplane; and
(e) The proposed manoeuvres will not bring the sailplane into close proximity with other aircraft (CAR 155(4)).
The GFA pre-aerobatic check is at Appendix 1.
Pre Aerobatic Check
page 61
PRE AEROBATIC CHECK HEIGHT – Sufficient for recovery by 1,000ft AGL.
AIRFRAME – Flaps, airbrakes, undercarriage set as required. Trim as required. Hatches and vents closed and locked as appropriate.
SECURITY – Harness secure. Loose objects stowed.
LOCATION – Clear of built-up areas, cloud, controlled airspace.
LOOKOUT – 180o plus 90o turns checking carefully around, above and underneath. Do not do a 360o turn.
Glider Stall Recovery
You don't need a motor to recover from the stall!
You recover from the stall by reducing the AoA to below the critical angle as in most other aircraft.
You recover from the stall by reducing the AoA to below the critical angle as in most other aircraft.
Excerpt from GFA Instructors' Handbook.
Airborne demonstrations and student practice
“We always carry out a “Pre-aerobatic check” particularly making sure there are no other
aircraft nearby, especially
aircraft nearby, especially
below... To make the glider stall, bring the nose above the normal
glide attitude and keep it there by gently and progressively bringing the stick further and further
glide attitude and keep it there by gently and progressively bringing the stick further and further
back...
Notice that the speed and nose are getting less, the controls are becoming less effective
and you may feel the onset of buffeting over the tail section and/or rear fuselage… There’s the
stall. The nose drops even with the stick right back... We move the stick progressively forward to
recover, speed increases and we fly it smoothly out of the dive... You will note that we were
unable to bring the nose up until we regained flying speed.”
and you may feel the onset of buffeting over the tail section and/or rear fuselage… There’s the
stall. The nose drops even with the stick right back... We move the stick progressively forward to
recover, speed increases and we fly it smoothly out of the dive... You will note that we were
unable to bring the nose up until we regained flying speed.”
The foregoing description of a typical stalling exercise covers the case of a glider which has a
natural nose-drop tendency at the stall. Note the key point - in spite of the stick coming back the
nose drops. In the case of a glider which does not have a natural nose-drop tendency (e.g. Twin
Astir), the key point is the stick arriving on the back stop and the variometer showing about 600 to
800 ft/min rate of descent.
Similarly, if a wing drops before the nose-down break occurs, this becomes the key point and
should be treated accordingly.natural nose-drop tendency at the stall. Note the key point - in spite of the stick coming back the
nose drops. In the case of a glider which does not have a natural nose-drop tendency (e.g. Twin
Astir), the key point is the stick arriving on the back stop and the variometer showing about 600 to
800 ft/min rate of descent.
Similarly, if a wing drops before the nose-down break occurs, this becomes the key point and
The recovery in all cases is identical - smooth progressive forward movement of the stick. It is not
sufficient to allow any natural nose-down tendency the glider may have to “self recover” from the
stall. Positive action must be taken by the pilot. Neither is it sufficient to move the stick forward
to some pre-determined point - the progressive forward movement must continue until the pilot
recognises that the wing is unstalled.sufficient to allow any natural nose-down tendency the glider may have to “self recover” from the
stall. Positive action must be taken by the pilot. Neither is it sufficient to move the stick forward
to some pre-determined point - the progressive forward movement must continue until the pilot
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Thanks guys. 1000' is quite low - not so much for spin safety I'm thinking - but for recovering to an airfield if you lose more height than expected. But I guess mostly the whole (rural) world is your landing field in a glider! 
I have conducted stalls at min. 1500' agl for flight testing, with the approval of the flying school and the relevant regulator. But 2500' to 3000' was more usual for training, even in that part of the world. I also failed at least one would-be instructor (nice guy, shame about his nerves) for briefing me 2500' agl minimum height, then conducting the demonstration stall at 1000' over rising ground. I was more concerned about his awareness than an arbitrary number in the Ops Manual.
I mention these examples to show the OP that 3000' is not the only standard. But in Australia, I would conform to general expectations; there's no compelling reason to do otherwise. Why single yourself out without powerful reason?
I have conducted stalls at min. 1500' agl for flight testing, with the approval of the flying school and the relevant regulator. But 2500' to 3000' was more usual for training, even in that part of the world. I also failed at least one would-be instructor (nice guy, shame about his nerves) for briefing me 2500' agl minimum height, then conducting the demonstration stall at 1000' over rising ground. I was more concerned about his awareness than an arbitrary number in the Ops Manual.
I mention these examples to show the OP that 3000' is not the only standard. But in Australia, I would conform to general expectations; there's no compelling reason to do otherwise. Why single yourself out without powerful reason?
How do glider pilots recover from the stall without an engine to blip?
By reducing the angle of attack below the stalling angle of attack, the same way any aircraft recovers from a stall.
I sincerely hope you are only an interested bystander, and not actually a pilot.
Tootle pip!!
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We use 2,500, and that low due to airspace restrictions. Wouldn't want to be any lower wing dropping in a c152, c172 is pretty much the same. if you don't recover there is a pretty good chance going into a spin/spiral and you are going to need some altitude before you becoming fixated on the ground rapidly approaching.
Sprucegoose
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Howard, Matt gave a talk at AUSFLY this year, it was one of the most entertaining, motivating & intriguing aviation talks I've listened too. He talked in depth about that incident, the full story was fascinating 
Wouldn't want to be any lower wing dropping in a c152, c172 is pretty much the same
So during flying school training, if a wing drop occurs at the point of stall and exceeds ten degrees, the aircraft is by definition un-airworthy and the maintenance release must be annotated as such. Usually a significant wing drop at the point of stall can be traced to defective rigging which is all the more reason to write up the defect before the next poor bugger kills himself. Few students or other pilots will do that in case they get the DCM by the CFI/owner/manager.
Of course if the pilot decides to haul the nose very high during the stalling practice in order to save time and get it to stall more quickly, then that invalidates the certification process.
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As an earlier poster said, doing a basic aerobatics endorsement will do wonders for your flying. Puts those "scary" stalls in perspective
You haven't lived until you've hammerheaded a botched wingover in an Aerobat 
it did, however (in my case at least) engender an enthusiasm which needed kerbing--afterwards, I went for a check ride in the local outfits brand new C172, and when asked to simulate a stall, at safe altitude, stood it on its tail. And was sternly admonished, rightly so, by the chief pilot, to tone it down. Best money, post PPL, that I ever spent on flying.
You haven't lived until you've hammerheaded a botched wingover in an Aerobat it did, however (in my case at least) engender an enthusiasm which needed kerbing--afterwards, I went for a check ride in the local outfits brand new C172, and when asked to simulate a stall, at safe altitude, stood it on its tail. And was sternly admonished, rightly so, by the chief pilot, to tone it down. Best money, post PPL, that I ever spent on flying.
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exactly, the best investment in your flying, en EMT course, or basic Aeros, and a decent engine course! will put to bed countless old wives tales handed down through the generations, doing the EMT and and engine course will prove just how wrong some are, and dangerous. cheap life insurance.
So during flying school training, if a wing drop occurs at the point of stall and exceeds ten degrees, the aircraft is by definition un-airworthy and the maintenance release must be annotated as such. Usually a significant wing drop at the point of stall can be traced to defective rigging which is all the more reason to write up the defect before the next poor bugger kills himself. Few students or other pilots will do that in case they get the DCM by the CFI/owner/manager.
A great number of factors outside (or inside) of the aircraft can cause one wing to stall before the other.
However a correctly handled/coordinated 1g power off level stall in these aircraft should barely roll at all.
I think the comment relates to that a 152 and 172 are easy to put into a spin situation if miss-handled as opposed to a PA28 which resist wing drops very well.