Standard Spin Recovery
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Must admit I am leaning more and more towards FI's who haven't got the aero's restriction removed being stopped from even demonstrating spin's.
For most light aeroplanes, one of the several variations on a document generically called "Part 23" is or was used for certification. They've never really changed much over the years, so quoting the latest European version which is called EASA CS.23,
(Paragraph 807 is about emergency exits and ability to abandon the aircraft by the way).
Later on in the document is a section on the POH requirements; this only requires that the recovery actions for compliance with this are listed in the manual.
Checking CS.22, which is the equivalent glider requirements they're pretty similar - the main difference being a requirement to meet them with water ballast, if that is carried.
With regard to flight test requirements, most of the world uses as a flight test guide for light civil aeroplane a US document called AC23.8B. Looking that up, it says (amongst several pages of other stuff related to spin testing) that:
This defines the "standard spin recovery"; however note this;
(1) It does not define the speed or rate of application of controls
(2) It uses the word "should" not "must" -which in flight-test-speak means that this is what you're looking for but if it doesn't work, the flight test team are at liberty to find something which does work and use that.
Mishandled ailerons and power, delayed recovery actions less than complete recovery actions, etc are all normal in a spin flight test programme. All are for the same reason - they're there to allow for a survivable event if the spin recovery was not flown properly.
G
CS 23.221 Spinning
(a) Normal Category aeroplanes. A single
engined, normal category aeroplane must be able
to recover from a one-turn spin or a three-second
spin, whichever takes longer, in not more than one
additional turn, after initiation of the first control
action for recovery. In addition –
(1) For both the flaps-retracted and
flaps-extended conditions, the applicable
airspeed limit and positive limit manoeuvring
load factor must not be exceeded;
(2) No control forces or characteristic
encountered during the spin or recovery may
adversely affect prompt recovery;
(3) It must be impossible to obtain
unrecoverable spins with any use of the flight or
engine power controls either at the entry into or
during the spin; and
(4) For the flaps extended condition, the
flaps may be retracted during the recovery but
not before rotation has ceased.
(b) Utility category aeroplanes. A utility
category aeroplane must meet the requirements of
sub-paragraph (a) . In addition, the requirements
of sub-paragraph (c) and CS 23.807 (b) (7) must
be met if approval for spinning is requested.
(c) Aerobatic category aeroplanes. An
aerobatic category aeroplane must meet the
requirements of sub-paragraph (a) and CS
23.807 (b) (6). In addition, the following
requirements must be met in each configuration for
which approval for spinning is requested –
(1) The aeroplane must recover from
any point in a spin up to and including six turns,
or any greater number of turns for which
certification is requested, in not more than one
and one-half additional turns after initiation of
the first control action for recovery. However,
beyond three turns, the spin may be
discontinued if spiral characteristics appear;
(2) The applicable airspeed limits and
limit manoeuvring load factors must not be
exceeded. For flaps-extended configurations
for which approval is requested, the flaps must
not be retracted during the recovery;
(3) It must be impossible to obtain
unrecoverable spins with any use of the flight or
engine power controls either at the entry into or
during the spin; and
(4) There must be no characteristics
during the spin (such as excessive rates of
rotation or extreme oscillatory motion) which
might prevent a successful recovery due to
disorientation or incapacitation of the pilot.
(a) Normal Category aeroplanes. A single
engined, normal category aeroplane must be able
to recover from a one-turn spin or a three-second
spin, whichever takes longer, in not more than one
additional turn, after initiation of the first control
action for recovery. In addition –
(1) For both the flaps-retracted and
flaps-extended conditions, the applicable
airspeed limit and positive limit manoeuvring
load factor must not be exceeded;
(2) No control forces or characteristic
encountered during the spin or recovery may
adversely affect prompt recovery;
(3) It must be impossible to obtain
unrecoverable spins with any use of the flight or
engine power controls either at the entry into or
during the spin; and
(4) For the flaps extended condition, the
flaps may be retracted during the recovery but
not before rotation has ceased.
(b) Utility category aeroplanes. A utility
category aeroplane must meet the requirements of
sub-paragraph (a) . In addition, the requirements
of sub-paragraph (c) and CS 23.807 (b) (7) must
be met if approval for spinning is requested.
(c) Aerobatic category aeroplanes. An
aerobatic category aeroplane must meet the
requirements of sub-paragraph (a) and CS
23.807 (b) (6). In addition, the following
requirements must be met in each configuration for
which approval for spinning is requested –
(1) The aeroplane must recover from
any point in a spin up to and including six turns,
or any greater number of turns for which
certification is requested, in not more than one
and one-half additional turns after initiation of
the first control action for recovery. However,
beyond three turns, the spin may be
discontinued if spiral characteristics appear;
(2) The applicable airspeed limits and
limit manoeuvring load factors must not be
exceeded. For flaps-extended configurations
for which approval is requested, the flaps must
not be retracted during the recovery;
(3) It must be impossible to obtain
unrecoverable spins with any use of the flight or
engine power controls either at the entry into or
during the spin; and
(4) There must be no characteristics
during the spin (such as excessive rates of
rotation or extreme oscillatory motion) which
might prevent a successful recovery due to
disorientation or incapacitation of the pilot.
Later on in the document is a section on the POH requirements; this only requires that the recovery actions for compliance with this are listed in the manual.
Checking CS.22, which is the equivalent glider requirements they're pretty similar - the main difference being a requirement to meet them with water ballast, if that is carried.
With regard to flight test requirements, most of the world uses as a flight test guide for light civil aeroplane a US document called AC23.8B. Looking that up, it says (amongst several pages of other stuff related to spin testing) that:
(8) Recovery. Recoveries should consist of throttle reduced to idle, ailerons neutralized, full opposite rudder, followed by forward elevator control as required to get the wing out of stall and recover to level flight. For acrobatic category spins, the manufacturer may establish additional recovery procedures, provided they show compliance for those procedures with this section.
(1) It does not define the speed or rate of application of controls
(2) It uses the word "should" not "must" -which in flight-test-speak means that this is what you're looking for but if it doesn't work, the flight test team are at liberty to find something which does work and use that.
Mishandled ailerons and power, delayed recovery actions less than complete recovery actions, etc are all normal in a spin flight test programme. All are for the same reason - they're there to allow for a survivable event if the spin recovery was not flown properly.
G
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It would seem reasonable for non aerobatic aircraft to comply with some sort of standard spin recovery and aerobatic types may need some modification which a pilot learns on checkout.
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Spinning Syllabus Requirements
It may not be entirely appropriate for me to comment on this forum as I don't hold an FIR (I will be commencing my training for the rating shortly though), so I apologise if I offend anyone.
On the subject of syllabus requirements: I have noted with some interest that in both the US and Europe there seems to be no requirement to spin an aeroplane 'for real' in training. I fly in Australia, and incipient spins and recoveries are mandatory during initial training. Students are not taught how to enter a spin, but they are both shown and practise the recovery techniques for their aircraft. There is further spin training undertaken during CPL training, which at my flying school takes to form of a 1.5hr lesson devoted entirely to clean stalls, advanced stalls and recovery from both incipient and fully developed spins in the C152 Aerobat. Aerobatics is also on offer during this lesson (and several others besides) for those who request it...which is most people!
I can't understand why in other countries it is not considered necessary for PPLs to receive spin training. I am not an authority, nor do I pretend to be, but to me it seems dangerous. I have never had a problem identifying spin direction, but I did find fully developed spins a little disorienting, particularly when buffet set in. I practised spin recovery around 20 times during my Commercial training, and I still have to take a split-second to recall the recovery technique - it's not quite an unconscious motor program yet.
For a PPL who has never practised spin recovery in the aeroplane and may have only received some ground school on the technique, I can only imagine the stark terror that would no doubt ensue upon unintentionally spinning an aeroplane - and it does happen. I know an FI who did it when they were in training.
Anyway, I just don't think it's the safest idea ever. I think the focus in other countries should be like it is here: on taking the fear and mystery out of the spin and making it just another manouevre, rather than focusing on spin-avoidance and turning the spin into a scary green-eyed monster.
On the subject of syllabus requirements: I have noted with some interest that in both the US and Europe there seems to be no requirement to spin an aeroplane 'for real' in training. I fly in Australia, and incipient spins and recoveries are mandatory during initial training. Students are not taught how to enter a spin, but they are both shown and practise the recovery techniques for their aircraft. There is further spin training undertaken during CPL training, which at my flying school takes to form of a 1.5hr lesson devoted entirely to clean stalls, advanced stalls and recovery from both incipient and fully developed spins in the C152 Aerobat. Aerobatics is also on offer during this lesson (and several others besides) for those who request it...which is most people!
I can't understand why in other countries it is not considered necessary for PPLs to receive spin training. I am not an authority, nor do I pretend to be, but to me it seems dangerous. I have never had a problem identifying spin direction, but I did find fully developed spins a little disorienting, particularly when buffet set in. I practised spin recovery around 20 times during my Commercial training, and I still have to take a split-second to recall the recovery technique - it's not quite an unconscious motor program yet.
For a PPL who has never practised spin recovery in the aeroplane and may have only received some ground school on the technique, I can only imagine the stark terror that would no doubt ensue upon unintentionally spinning an aeroplane - and it does happen. I know an FI who did it when they were in training.
Anyway, I just don't think it's the safest idea ever. I think the focus in other countries should be like it is here: on taking the fear and mystery out of the spin and making it just another manouevre, rather than focusing on spin-avoidance and turning the spin into a scary green-eyed monster.
There is a thread currently running about this topic in the Flight Testing forum.
My 2 cents worth: Although people often refer to a "standard spin recovery" and there is a recovery technique which works for the majority of types around, you should know and apply the recovery technique for your aircraft type as described in the POH. I have regularly spun six types of aircraft in my instructional career and all had different techniques. The recovery technique for one of those would put another type into a high rotational spin. A lot of aircraft are reluctant to spin and will only do so if full pro spin control is held. Some of these recover if the controls are just centralised. However, a few don't and this is where the danger lies.
A lot of people refer to the Muller technique. This is essentially centralising. It works for most types, particularly the aerobatic types for which this technique was developed. But I can think of one type I have flown where it wouldn't work.
One thing I have found in the PPL world is that where spin instruction is done, the emphasis is on the entry and recovery to the full spin. It is very unlikely that a full spin is going to be entered inadvertantly by any pilot. So I'm not sure of the validity of this training. Military pilots are taught to enter and recover academic full spins, but their flying career is going to require them to handle aircraft at the extremes of the envelope - somewhere the PPL or commercial pilot trainee is not going to go unless he/she is going to fly competition aerobatics. Military training emphasises spin recognition and recovery at the incipient phase if possible. The full spin is defined (in the RAF) as when the aerodynamic and gyroscopic forces have balanced. In a typical straight wing type such as the Chipmunk, this is usually in the first turn. prior to this, it is the incipient phase and the recovery technique is to centralise the controls and close the throttle (essentially, the Muller technique). Of course, the pilot may not be entering an acedemic spin from straight and level. So the emphasis is on recognising that if you have buffet and undemanded roll, you are in an incipient spin.
The JAR PPL syllabus has dispensed with spinning, and for good reaon. More people have been killed paracticing it than have been saved. A freind of mine died in this situation a few years ago. Recovery emphais is on recovering from any situation with buffet. If there is a wing drop at the stall, this could be a incipient spin. The recovery is essentially the same.
I was also once a gliding instructor and a form of standard spin recovery was used in that world as most gliders enter and recover very quickly. And as gliders spend most of their flying at VIMD which in some cases is only a few knots above the stall, spin training is relevant and necessary. Most are safe. However, there are some gliders which have horrible (and in some cases dangerous) spin characteristics. Anyone here who has spun a Bocian will know what I mean!
My 2 cents worth: Although people often refer to a "standard spin recovery" and there is a recovery technique which works for the majority of types around, you should know and apply the recovery technique for your aircraft type as described in the POH. I have regularly spun six types of aircraft in my instructional career and all had different techniques. The recovery technique for one of those would put another type into a high rotational spin. A lot of aircraft are reluctant to spin and will only do so if full pro spin control is held. Some of these recover if the controls are just centralised. However, a few don't and this is where the danger lies.
A lot of people refer to the Muller technique. This is essentially centralising. It works for most types, particularly the aerobatic types for which this technique was developed. But I can think of one type I have flown where it wouldn't work.
One thing I have found in the PPL world is that where spin instruction is done, the emphasis is on the entry and recovery to the full spin. It is very unlikely that a full spin is going to be entered inadvertantly by any pilot. So I'm not sure of the validity of this training. Military pilots are taught to enter and recover academic full spins, but their flying career is going to require them to handle aircraft at the extremes of the envelope - somewhere the PPL or commercial pilot trainee is not going to go unless he/she is going to fly competition aerobatics. Military training emphasises spin recognition and recovery at the incipient phase if possible. The full spin is defined (in the RAF) as when the aerodynamic and gyroscopic forces have balanced. In a typical straight wing type such as the Chipmunk, this is usually in the first turn. prior to this, it is the incipient phase and the recovery technique is to centralise the controls and close the throttle (essentially, the Muller technique). Of course, the pilot may not be entering an acedemic spin from straight and level. So the emphasis is on recognising that if you have buffet and undemanded roll, you are in an incipient spin.
The JAR PPL syllabus has dispensed with spinning, and for good reaon. More people have been killed paracticing it than have been saved. A freind of mine died in this situation a few years ago. Recovery emphais is on recovering from any situation with buffet. If there is a wing drop at the stall, this could be a incipient spin. The recovery is essentially the same.
I was also once a gliding instructor and a form of standard spin recovery was used in that world as most gliders enter and recover very quickly. And as gliders spend most of their flying at VIMD which in some cases is only a few knots above the stall, spin training is relevant and necessary. Most are safe. However, there are some gliders which have horrible (and in some cases dangerous) spin characteristics. Anyone here who has spun a Bocian will know what I mean!
Last edited by Dan Winterland; 25th May 2008 at 04:51.
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A lot of aircraft are reluctant to spin and will only do so if full pro spin control is held. Some of these recover if the controls are just centralised.
-----------
Aerohooligan,
In the JAA sylabus students must demonstrate proficiency in stall recognition and recovery both that the incipient stage and the developed stage in various configurations, power on and off as well as accelerated stalls.
They have also to demonstrate proficiency in spin recoveries at the incipient stage.
They are required to demonstrate knowledge of the recovery actions from a developed spin.
If you don't want to spin - then don't ever stall is a very good way of looking at the issue.
I do agree that in the unexpected fully developed spin at 1000ft, the "pilot" is going to be unlikely to recover if they have never been in a spin before.
However, is the student scared to death up at 6000ft arriving home green and not wishing to ever do that again actually in any better a position?
Stopping it from spinning in the first place (stall avoidance / recovery / incipient spin recovery) works best especially at 500ft AGL - base to final turn / climbout after late go-arround.
Regards,
DFC
Quote: Yes. Even the PA38 (which gets lots of bad press regarding spins) will recover from a spin stick free.
Those of you who spin the PA38, next time you do - bend your head back and have a look at the tail. You won't be so keen to do it again!
Those of you who spin the PA38, next time you do - bend your head back and have a look at the tail. You won't be so keen to do it again!
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Dan.
I spent years spinning Tomahawks at Oxford, including looking back at the tail as it boomed, and the exercise never gave me a moment of concern. There had been a fatality at the school on a spinning detail and the then CAA chief test pilot did an exhaustive survey of the spinning characteristics and gave it a clean bill of health. There's a lot of folklore about spinning the 38 but the reality is less entertaining. You have to be my vintage to have instructed when spinning formed part of the PPL syllabus. I suspect that a lot of the misgivings in younger instructors stem from the fact that they're not doing it on a daily basis. For what it's worth, I always took the view that spinning was primarily valuable in exposing the student to the outside edge of the envelope and showing that he could recover to S&L.
I spent years spinning Tomahawks at Oxford, including looking back at the tail as it boomed, and the exercise never gave me a moment of concern. There had been a fatality at the school on a spinning detail and the then CAA chief test pilot did an exhaustive survey of the spinning characteristics and gave it a clean bill of health. There's a lot of folklore about spinning the 38 but the reality is less entertaining. You have to be my vintage to have instructed when spinning formed part of the PPL syllabus. I suspect that a lot of the misgivings in younger instructors stem from the fact that they're not doing it on a daily basis. For what it's worth, I always took the view that spinning was primarily valuable in exposing the student to the outside edge of the envelope and showing that he could recover to S&L.
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There had been a fatality at the school on a spinning detail and the then CAA chief test pilot did an exhaustive survey of the spinning characteristics and gave it a clean bill of health.
Spinning and trying to recover with the stick fully back (an abused recovery) introduces a secondary spin mode in the PA38. The secondary mode varies from airframe to airframe in the PA38 series but overall- the aircraft will pitch down against elevator and the rotation rate will increase against the opposing rudder.
Even with this secondary mode, recovery will happen when the control column is moved forward to the max and held there.
If one forgets what the POH says and uses the "standard spin recovery procedure" in a PA38 then the aircraft will not enter the secondary spin mode mentioned - even if the stick is released and opposite rudder apllied it will recover.
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There are aircraft flying where flexing of the tail during spin and recovery had to be investigated and a camera mounted looking back was used. The PA38 had no such problems despite what people might think.
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I agree that most of today's instructors lack experience and confidence in spinning and thus the demo if provided simply results in two people sitting there in a competition as to who is going to be scared the most!!
Regards,
DFC
Originally Posted by bristolscout
There had been a fatality at the school on a spinning detail and the then CAA chief test pilot did an exhaustive survey of the spinning characteristics and gave it a clean bill of health.
G
Don't get me wrong, I wasn't knocking the PA38. It's quite a reasonable trainer and it's spin characteristics are sound. It just needs a slightly different recovery technique to other popular training types - which re-enforces my point that there is no standard spin recovery for all types. It does actually spin properly, unlike the C150/2.
My comment was referring to the slightly alarming movement of the tail during the spin. The only thing I have against it is that there's no room to wear a parachute. One of my main requisites for spinning!
My comment was referring to the slightly alarming movement of the tail during the spin. The only thing I have against it is that there's no room to wear a parachute. One of my main requisites for spinning!
Last edited by Dan Winterland; 2nd Jun 2008 at 01:41. Reason: spilling
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To be or not to be ......!
But Dan
With all respect, your point does not re-enforce your arguements at all. With all that I have read and know with regard to the 'Standard Spin Recovery' generally being taught by many, including myself on many occasions and including on the PA38, is that it has never been claimed to replace the specific POH recovery action. Some older aircraft manuals in fact are very vague. The PA38 manual, eventually, had to be re-written.
A pilot within a professional public transport or military environment will usually be flying only one type at a time and will be given extensive and expensive recurrent training. It is therefore much more straightforward to train the professional for the specific. The average PPL flying 12 to 25 hours a year will commonly have access to several very different types and retain currency by a simple short club checkout lasting maybe a few minutes. To demand more would be too costly and impracticable.
The law requires in JAA land that a PPL holder is only required to be trained for 1 hour every 2nd year and only then when no test has been undertaken for any other pilot licensing purpose such as; a multi-engine renewal or an LPC for his airline.
The 'standard recovery' will work across most the types normally flown by PPL holders, perhaps only sufficient, to save life which otherwise might be lost. For a pilot to be expected to retain several different specific techniques in their head for each type they fly, in case they may find themselves un-intentionally in a spin, is naive and probably dangerous.
With all respect, your point does not re-enforce your arguements at all. With all that I have read and know with regard to the 'Standard Spin Recovery' generally being taught by many, including myself on many occasions and including on the PA38, is that it has never been claimed to replace the specific POH recovery action. Some older aircraft manuals in fact are very vague. The PA38 manual, eventually, had to be re-written.
A pilot within a professional public transport or military environment will usually be flying only one type at a time and will be given extensive and expensive recurrent training. It is therefore much more straightforward to train the professional for the specific. The average PPL flying 12 to 25 hours a year will commonly have access to several very different types and retain currency by a simple short club checkout lasting maybe a few minutes. To demand more would be too costly and impracticable.
The law requires in JAA land that a PPL holder is only required to be trained for 1 hour every 2nd year and only then when no test has been undertaken for any other pilot licensing purpose such as; a multi-engine renewal or an LPC for his airline.
The 'standard recovery' will work across most the types normally flown by PPL holders, perhaps only sufficient, to save life which otherwise might be lost. For a pilot to be expected to retain several different specific techniques in their head for each type they fly, in case they may find themselves un-intentionally in a spin, is naive and probably dangerous.
-we've all heard of PARE
now, what about Beggs Mueller Emergency recovery---The book Basic Aerobatics by Mike Goulian and Geza Sverozy, details it very wonderfully
but the basics.....
Power off
Let go of stick--completely--- allow the controls to neutralize -let the ship return to its natural stability
Full rudder against the YAW--so you can do it inverted too
Full Elevator, down for upright, up for inverted---when ASI is ok--and the ship is not mushing recover from dive---it usually works
PA
now, what about Beggs Mueller Emergency recovery---The book Basic Aerobatics by Mike Goulian and Geza Sverozy, details it very wonderfully
but the basics.....
Power off
Let go of stick--completely--- allow the controls to neutralize -let the ship return to its natural stability
Full rudder against the YAW--so you can do it inverted too
Full Elevator, down for upright, up for inverted---when ASI is ok--and the ship is not mushing recover from dive---it usually works
PA
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"Standard Spin Recovery" no such thing.
Firstly is it a "standard" recovery checklist, or a checklist used recover from a "Standard" spin (whatever that is!)
Flat, inverted and Knife edge spins all require different actions, and so by definition their can be no "Standard checklist"
Mueller and Cassidy have well described emergency vital actions, that are the only procedures that come to a complete cover all.
Each type also has its own specific attributes, power on during recovery will make the recovery quicker, Aileron input can stop the spin alone, etc etc.
Knowing "Standard spin recovery" is not a green light to spin any type. Each type will have a specific set of actions.
Fcirc
Firstly is it a "standard" recovery checklist, or a checklist used recover from a "Standard" spin (whatever that is!)
Flat, inverted and Knife edge spins all require different actions, and so by definition their can be no "Standard checklist"
Mueller and Cassidy have well described emergency vital actions, that are the only procedures that come to a complete cover all.
Each type also has its own specific attributes, power on during recovery will make the recovery quicker, Aileron input can stop the spin alone, etc etc.
Knowing "Standard spin recovery" is not a green light to spin any type. Each type will have a specific set of actions.
Fcirc
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An old (in both senses) mate did a lot of work on the Chipmunk spin problem, in Oz I think, while still in the RAF. 1960's? Probably.
He told me that they eventually concluded that the reason so many did not recover was that pilots thought the stick was fully forward when it wasn't; it seemed to reach a stop but that was aerodynamic.
They recommended that the boot not being used for full rudder deflection should be used to push the stick forward another inch or two at the top, unless the pilot had long enough arms to do it with.
That was, I think, after the aft end was redesigned a bit to try and fix the problem.
He told me that they eventually concluded that the reason so many did not recover was that pilots thought the stick was fully forward when it wasn't; it seemed to reach a stop but that was aerodynamic.
They recommended that the boot not being used for full rudder deflection should be used to push the stick forward another inch or two at the top, unless the pilot had long enough arms to do it with.
That was, I think, after the aft end was redesigned a bit to try and fix the problem.
Homeguard. Yes, I can see your point that a 'standard' technique may save lives. But I have to emphasise the 'may'.
When the PA38 was designed, it was the result of Piper asking 10,000 instructors what they wanted in a training aircraft. Piper designed it to spin - because that's what instructors wanted. However, spin fatalities racked up on this type because it's spin characteristics were different to the common training type in use at the time, the C150/2. It took longer to recover (becuase the Tomahawk's spin is a true spin, whereas the C150/2's is more of a descending spiral with one wing slightly stalled) and this led to confusion during the recovery which in turn led to delayed recoveries and consequent crashes. Another aircraft which had different recovery characteristics on introduction is the T67, which is different to the Chipmunk, which is different to the Bulldog etc.
You are talking about recovery actions in the case of an inadvertant spin. The recovery for any spin in the incipient stage is the same. Centralise and close the throttle. This should be enough for the PPL flying various types -and this is what is in the PPL syllabus. Correct recognition and appropriate recovery actions are all that is deemed necessary. If your PPL then goes off and deliberately full spins an aircraft without adequate instruction or referring to the POH thus not knowing the recovery technique for that type, the he/she will significantly increase their chance of becoming a statistic.
Capot - The Chippie is the aircraft I have spun the most, I have never had any exciting moments in about a thousand spins. But that's thanks to the research which people like your mate carried out. The modifications including the wider chord rudder and the spin strakes did the trick. But these were tied in with a change in recovery technique. The aerodynamic lock was caused by a lack of airflow over the elevator. The spin strakes energised the airflow and the new technique was to pause before moving the control column forward to allow the 'straightened flow' to take effect. As a result, the stick never had to go so far forward and recoveries were positive and fairly prompt after that.
But these were all from the standard executed entry which involved applying full pro spin controls at 50 knots - a few knots above the stall therefore slightly 'flicking' the aircraft into the spin. This led to a balanced and stable spin which showed the classic one turn incipient stage before entering the the fully developed stage. If you had an aircraft which dropped a wing at the stall (and a lot in the fleet did as they were now getting close to 50 years old!) and you attempted to pick up the wing with aileron - it would enter a flat slowly rotaing spin with lots of buffet, a much shallower nose down attitude which was in the fully develped stage at about a third of a turn, and which took longer to recover.
The Chipmunk, the Bulldog and the PA38 all had spinning testing re-visited after their introduction with a subsequent change in the recovery techniques. Sadly, these were all after fatal accidents.
There is no standard spin recovery.
When the PA38 was designed, it was the result of Piper asking 10,000 instructors what they wanted in a training aircraft. Piper designed it to spin - because that's what instructors wanted. However, spin fatalities racked up on this type because it's spin characteristics were different to the common training type in use at the time, the C150/2. It took longer to recover (becuase the Tomahawk's spin is a true spin, whereas the C150/2's is more of a descending spiral with one wing slightly stalled) and this led to confusion during the recovery which in turn led to delayed recoveries and consequent crashes. Another aircraft which had different recovery characteristics on introduction is the T67, which is different to the Chipmunk, which is different to the Bulldog etc.
You are talking about recovery actions in the case of an inadvertant spin. The recovery for any spin in the incipient stage is the same. Centralise and close the throttle. This should be enough for the PPL flying various types -and this is what is in the PPL syllabus. Correct recognition and appropriate recovery actions are all that is deemed necessary. If your PPL then goes off and deliberately full spins an aircraft without adequate instruction or referring to the POH thus not knowing the recovery technique for that type, the he/she will significantly increase their chance of becoming a statistic.
Capot - The Chippie is the aircraft I have spun the most, I have never had any exciting moments in about a thousand spins. But that's thanks to the research which people like your mate carried out. The modifications including the wider chord rudder and the spin strakes did the trick. But these were tied in with a change in recovery technique. The aerodynamic lock was caused by a lack of airflow over the elevator. The spin strakes energised the airflow and the new technique was to pause before moving the control column forward to allow the 'straightened flow' to take effect. As a result, the stick never had to go so far forward and recoveries were positive and fairly prompt after that.
But these were all from the standard executed entry which involved applying full pro spin controls at 50 knots - a few knots above the stall therefore slightly 'flicking' the aircraft into the spin. This led to a balanced and stable spin which showed the classic one turn incipient stage before entering the the fully developed stage. If you had an aircraft which dropped a wing at the stall (and a lot in the fleet did as they were now getting close to 50 years old!) and you attempted to pick up the wing with aileron - it would enter a flat slowly rotaing spin with lots of buffet, a much shallower nose down attitude which was in the fully develped stage at about a third of a turn, and which took longer to recover.
The Chipmunk, the Bulldog and the PA38 all had spinning testing re-visited after their introduction with a subsequent change in the recovery techniques. Sadly, these were all after fatal accidents.
There is no standard spin recovery.
Those Chipmunk tests were reported in the June 1960 edition of the Aviation Safety Digest. Just skimmed through it tonight. Didn't see any mention of the boot on the stick (may have missed it) but saw mention of one Chipmunk instructor having to take over from his student "and only recovered by moving the throttle and stick forward and back together."
CASA has retained that in their Flight Instructor Manual as note (ii) of their emergency recovery technique.
Please don't shoot the messenger.
CASA has retained that in their Flight Instructor Manual as note (ii) of their emergency recovery technique.
Please don't shoot the messenger.
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There is no standard spin recovery.
a) Is used when no other technique has been established
b) Used if you can not remember the POH and don't have the altitude to consult the relevant paragraph; and
c) Is specified in the flight training texts which are non-type specific.
Regards,
DFC