Reports of a light aircraft down in Blue Mountains
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The PIC reported that at this time he performed his normal recovery procedure from this manoeuvre: maintained a neutral aileron control position, applied forward pressure on the control stick to pitch the aircraft nose down, rudders neutral and applied power.
The passenger in the front seat reported that he applied full left rudder in an attempt to counter the rotation.
As the rate of rotation to the right slowed, the passenger in the front seat felt the PIC apply right rudder, and the aircraft again accelerated rotating to the right.
As the rate of rotation to the right slowed, the passenger in the front seat felt the PIC apply right rudder, and the aircraft again accelerated rotating to the right.
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Interestingly, during the "spin" the indicated airspeed increased from 62 knots to 140 knots, which doesn't actually sound like a spin. The vertical speed also increases with the airspeed.
140 knots with between 50 and 70 degrees pitch down would indeed give an impressive rate of descent.
Quotes from the POH in the report:
"In some cases it may be difficult to determine if the aircraft has entered a spiral or the beginning of a spin."
and:
"if the aircraft enters an unusual attitude from which recovery is not expected before ground impact, immediate deployment of the CAPS is required"
Good advice
It sounds to me like the PIC/salesman was (as he noted) "overconfident as he had done the demonstration 30-50 times" previously and unprepared for the resulting unusual attitude.
I don't believe it was an actual spin due to the steadily increasing and resulting high IAS value. It looks like a spiral that possibly it could have been recovered by closing the throttle, rolling wings level and pulling out of the dive. That may have been difficult due to airspeed/G/altitude limits.
The CAPS certainly saved the day, and the PIC made the correct decision following the loss of control.
I don't think much blame can be put on the aircraft here, except perhaps for inducing overconfidence in the pilot. Might similar performance aircraft e.g. a Bonanza also occasionally drop a wing and enter a spiral if you did a similar stall (25 degree bank, flap, adding power as it stalls)?
140 knots with between 50 and 70 degrees pitch down would indeed give an impressive rate of descent.
Quotes from the POH in the report:
"In some cases it may be difficult to determine if the aircraft has entered a spiral or the beginning of a spin."
and:
"if the aircraft enters an unusual attitude from which recovery is not expected before ground impact, immediate deployment of the CAPS is required"
Good advice
It sounds to me like the PIC/salesman was (as he noted) "overconfident as he had done the demonstration 30-50 times" previously and unprepared for the resulting unusual attitude.
I don't believe it was an actual spin due to the steadily increasing and resulting high IAS value. It looks like a spiral that possibly it could have been recovered by closing the throttle, rolling wings level and pulling out of the dive. That may have been difficult due to airspeed/G/altitude limits.
The CAPS certainly saved the day, and the PIC made the correct decision following the loss of control.
I don't think much blame can be put on the aircraft here, except perhaps for inducing overconfidence in the pilot. Might similar performance aircraft e.g. a Bonanza also occasionally drop a wing and enter a spiral if you did a similar stall (25 degree bank, flap, adding power as it stalls)?
[quoteMight similar performance aircraft e.g. a Bonanza also occasionally drop a wing and enter a spiral if you did a similar stall (25 degree bank, flap, adding power as it stalls)][/quote]
I think the answer is almost certainly no.
Bonanza and other competitive high performance aircraft all did spin testing as part of the certification process. Cirrus did not.
I think the answer is almost certainly no.
Bonanza and other competitive high performance aircraft all did spin testing as part of the certification process. Cirrus did not.
Might similar performance aircraft e.g. a Bonanza also occasionally drop a wing and enter a spiral if you did a similar stall (25 degree bank, flap, adding power as it stalls)?
Far more benign that the Traumahawk that I used to instruct in which would consistently roll on its back if stalled with flaps and power.
Dr
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Isn't spin testing to prove that an aircraft which has entered a spin is able to recover using usual recovery methods? I don't think it means they will not spin. Some aircraft need more provocation than others before they will spin.
Isn't spin testing to prove that an aircraft which has entered a spin is able to recover using usual recovery methods? I don't think it means they will not spin. Some aircraft need more provocation than others before they will spin.
Anyone who spins a Cirrus is taking on the role of test pilot and doing something that the designers and manufacturers have not done (or if they have - did not release results).
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Anyone who spins a Cirrus is taking on the role of test pilot and doing something that the designers and manufacturers have not done (or if they have - did not release results).
The report you linked to says spin testing was conducted with more than 60 spin entries, and:
"The aircraft recovered within one turn in all cases examined ... Altitude loss from spin entry to recovery ranged from 1,200 – 1,800 feet."
however they did not test all cases in the spin test matrix, and say that it must be assumed that there are some unrecoverable characteristics.
The report also says:
"A majority of the general aviation pilot population do not receive any spin recovery training whatsoever...
The reliability level of a general aviation pilot to properly react in a loss of control condition in any type of airplane is historically low (see the FAA statistics...
While a small percentage of Cirrus pilots may be able to successfully recover from an inadvertent spin, Cirrus contends that the far larger portion of pilots would not do so in a surprise departure spin situation...
Cirrus believes it is better to accept some airframe losses through CAPS activation when the airplane could have been flown away following a successful recovery, in order to save the lives of the far larger number of pilots who would not be able to successfully execute a spin recovery...
Cirrus has reached strong conclusion that any spin recovery guidance in the AFM distracts pilot from immediately activating CAPS system when the aircraft has departed controlled flight. Cirrus is removing existing references to spin recovery in its current AFM. The clear AFM procedure will be to activate CAPS system in the event that control is lost."
They say that it is safer to activate the CAPS than attempt to recover, and it is possible that there are some unrecoverable configurations. That is different to saying it will not recover at all, or it has never been spun.
I don't know why you say that, when you previously linked to a report describing Cirrus spin testing and results?
The footnote to one of the tables bothers me when it says that all spins were conducted at gross weight. This infers only one loading condition was tested. It is also unlikely to be the critical spin condition which is almost certainly aft c of g and may occur at a weight below MTOW.
I'm not saying the Cirrus can or cannot spin. I'm just saying that unlike its mainstream competitors, Cirrus side stepped the certification spin testing.
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Cirrus, get your act together, if these guys can do it, spin testing a 4 seat aircraft, with 4 pax, and 3/4 fuel, and not just incipient entry, but a developed, stabilised, 10 rotation spin. in an aircraft with equal, or better performance than the Cirrus.
They must be bloody confident (or brave) to put 4 people in a prototype aircraft and do a ten-turn spin... :o
lovely aircraft, btw. I hope it's not built for Pipistrel midgets
lovely aircraft, btw. I hope it's not built for Pipistrel midgets
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Cirrus claim that a parchute is best recovery method rather than relying on pilot skill is spin spin spin.
Awesome marketing to promote an aircraft's deficiency and inability to comply with a certification requirement as a safety BENEFIT.
If it will recover from some configurations but not others in the matrix, that is a non compliance, FAIL.
Compliance with FAR 23 requires a normal pilot of normal ability, using conventional techniques without excessive force or exceptional skill, to be able to recover IAW procedure specified in POH.
Demonstration of compliance requires one turn spin and recovery in no more than one additional turn. If this is not able to be met then it is a FAIL.......so.... On with a ballistic chute and, hey presto, safer than compliance....... NOT. This is equivalent safety determination, but really should be regarded as an exception, or an exemption from requirement to show compliance by regulatory authority FAA. Lucky Cirrus was US owned and not Chinese back then or it may have been a very different outcome.
Fail to recover is fail to recover.
Another method to aviod spin recovery is to make aircraft 'spin resistant' basically meaning won't spin. Usually far too hard to demonstrate.
Remember, of course, that FAR 23 is a fluid document and that spin recovery for older aircraft does not meet current standards. We are in the amendment 60's at this time. Many FAR 23 aircraft, like the Cirrii, will not recover to full current requirments because FAR23 standards have been made more rigourous over the years with higher amendment status.
Bonanza......FAR 23......?????? Or CAR 3 from the 1950's, different standards? dont hold the Bonny up as a shining example of FAR 23 please.
Beware of any demo pilot who says "watch this"
Except me, te he he
HD
Awesome marketing to promote an aircraft's deficiency and inability to comply with a certification requirement as a safety BENEFIT.
If it will recover from some configurations but not others in the matrix, that is a non compliance, FAIL.
Compliance with FAR 23 requires a normal pilot of normal ability, using conventional techniques without excessive force or exceptional skill, to be able to recover IAW procedure specified in POH.
Demonstration of compliance requires one turn spin and recovery in no more than one additional turn. If this is not able to be met then it is a FAIL.......so.... On with a ballistic chute and, hey presto, safer than compliance....... NOT. This is equivalent safety determination, but really should be regarded as an exception, or an exemption from requirement to show compliance by regulatory authority FAA. Lucky Cirrus was US owned and not Chinese back then or it may have been a very different outcome.
Fail to recover is fail to recover.
Another method to aviod spin recovery is to make aircraft 'spin resistant' basically meaning won't spin. Usually far too hard to demonstrate.
Remember, of course, that FAR 23 is a fluid document and that spin recovery for older aircraft does not meet current standards. We are in the amendment 60's at this time. Many FAR 23 aircraft, like the Cirrii, will not recover to full current requirments because FAR23 standards have been made more rigourous over the years with higher amendment status.
Bonanza......FAR 23......?????? Or CAR 3 from the 1950's, different standards? dont hold the Bonny up as a shining example of FAR 23 please.
Beware of any demo pilot who says "watch this"
Except me, te he he
HD
