Stawell crash
Folks,
I am guilty of no more than not being pedantic enough about "self certification certification" versus what you assume as "certification", at the end of the day, these aircraft have still been "certified" to an "appropriate" mechanism.
As for the adequacy of the flight testing under the ASTM standards, I can only describe it as minimal, or "rough and ready" and in no way as extensive as a FAR 23 single engine (just to be pedantic) aircraft test requirements.
Tootle pip!!
PS: At least two imported LSA that I have inspected very closely during assembly have been real shockers, I would expect better from the average home builder.
Interestingly, CASA demanded that the incorrect assembly instructions of the manufacturer/certifier be followed to the letter, because anything else would be a "modification" not approved by the manufacturer/certifier.
PS2: Re. the Brumby, I was hoping to make the point that it was tested to well beyond the minimal required standards.
I am guilty of no more than not being pedantic enough about "self certification certification" versus what you assume as "certification", at the end of the day, these aircraft have still been "certified" to an "appropriate" mechanism.
As for the adequacy of the flight testing under the ASTM standards, I can only describe it as minimal, or "rough and ready" and in no way as extensive as a FAR 23 single engine (just to be pedantic) aircraft test requirements.
Tootle pip!!
PS: At least two imported LSA that I have inspected very closely during assembly have been real shockers, I would expect better from the average home builder.
Interestingly, CASA demanded that the incorrect assembly instructions of the manufacturer/certifier be followed to the letter, because anything else would be a "modification" not approved by the manufacturer/certifier.
PS2: Re. the Brumby, I was hoping to make the point that it was tested to well beyond the minimal required standards.
Last edited by LeadSled; 8th Oct 2018 at 03:38. Reason: PS2 added
I am guessing that Soar are confident they know what went wrong as they are still currently flying their other Bristells, so seemingly not too concerned.
I am quite confident that SOAR do not know what they are doing. Except ripping people off.
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Re. the Brumby, I was hoping to make the point that it was tested to well beyond the minimal required standards.
If I recall, media reports described the aircraft in a flat spin.
Report out.
https://www.atsb.gov.au/media/577817...-066_final.pdf
The pilot’s recollection of events and what actually happened appear to differ somewhat.
https://www.atsb.gov.au/media/577817...-066_final.pdf
The pilot’s recollection of events and what actually happened appear to differ somewhat.
Last edited by Cloudee; 29th Jun 2020 at 10:24.
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[QUOTE=Cloudee;10824201 The pilot’s recollection of events and what actually happened appear to differ somewhat.[/QUOTE]
yikes, wonder if they were aware of the data recording or if it was a bit of a gotcha moment.
Looking at a triple figure bank angle I can imagine some selective amnesia creep in
yikes, wonder if they were aware of the data recording or if it was a bit of a gotcha moment.
Looking at a triple figure bank angle I can imagine some selective amnesia creep in
1. I don't understand the spin recovery method in the POH per that ATSB report:
"Unintentional spin recovery technique:
1. Throttle - idle
2. Lateral control - ailerons neutralized
3. Rudder pedals - full opposite rudder
4. Rudder pedals - neutralize rudder immediately when rotation stops
5. Longitudinal control - neutralize or push forward and recover dive."
It suggests that only after the rotation stops is the elevator moved down and then used to recover from the dive.
2. "CASA’s assessment of the new flight testing data and further information supplied by the manufacturer was that it still did not confirm that the aircraft met the required ASTM standard for spin recovery." CASA still hasn't explained why they think that. I would've thought that the ATSB would've read the spin test report themselves and came to a conclusion themselves.
The method of recovery from a fully developed spin may be quite different from that in the POH intended to be used up to one turn.
"Idiot" "unacceptable behavior" I wonder if anyone had told him what he needed to know.
"Unintentional spin recovery technique:
1. Throttle - idle
2. Lateral control - ailerons neutralized
3. Rudder pedals - full opposite rudder
4. Rudder pedals - neutralize rudder immediately when rotation stops
5. Longitudinal control - neutralize or push forward and recover dive."
It suggests that only after the rotation stops is the elevator moved down and then used to recover from the dive.
2. "CASA’s assessment of the new flight testing data and further information supplied by the manufacturer was that it still did not confirm that the aircraft met the required ASTM standard for spin recovery." CASA still hasn't explained why they think that. I would've thought that the ATSB would've read the spin test report themselves and came to a conclusion themselves.
The method of recovery from a fully developed spin may be quite different from that in the POH intended to be used up to one turn.
"Idiot" "unacceptable behavior" I wonder if anyone had told him what he needed to know.
Possibly in another aircraft that was demonstrated as being able to meet the required standards, may have never entered the spin in the first place.
Plenty of pilots have gone to 90 degrees or more when showing off and not come close to entering a spin.
Plenty of pilots have gone to 90 degrees or more when showing off and not come close to entering a spin.
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I’m not qualified to critique the spin recovery in the POH but I feel like when you’ve significantly exceeded the aircraft’s stated performance as was done here then the POH pretty much goes out the window.
Perhaps there are plenty of GA aircraft that could have done what was done here and not had an accident outcome. The decision to do it in this particular type though is evidently flawed. That they had decided to do it earlier at a low altitude over a mate‘s house as well.....
Perhaps there are plenty of GA aircraft that could have done what was done here and not had an accident outcome. The decision to do it in this particular type though is evidently flawed. That they had decided to do it earlier at a low altitude over a mate‘s house as well.....
1. I don't understand the spin recovery method in the POH per that ATSB report:
"Unintentional spin recovery technique:
1. Throttle - idle
2. Lateral control - ailerons neutralized
3. Rudder pedals - full opposite rudder
4. Rudder pedals - neutralize rudder immediately when rotation stops
5. Longitudinal control - neutralize or push forward and recover dive."
It suggests that only after the rotation stops is the elevator moved down and then used to recover from the dive.
"Unintentional spin recovery technique:
1. Throttle - idle
2. Lateral control - ailerons neutralized
3. Rudder pedals - full opposite rudder
4. Rudder pedals - neutralize rudder immediately when rotation stops
5. Longitudinal control - neutralize or push forward and recover dive."
It suggests that only after the rotation stops is the elevator moved down and then used to recover from the dive.
"In all cases the aircraft responded to control actions and immediately recovered from a spin or spiral using “classic“ spin recovery sequence – full opposite rudder and elevator control push to neutral position. Just as the aircraft stops the rotation, rudder pedals were moved to neutral position." and "Recovery from the flat spin requires that engine power must be reduced to idle, full opposite rudder applied with ailerons and elevator in neutral position. It takes up to 2 turns to stop the flat spin. Once stopped, rudder pedals in neutral position, increase engine power, push stick slightly forward and recover to horizontal flight in the normal manner."
I’ll ask Gerard next time I see him.
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I’ll ask Gerard next time I see him.
And Lappin will tell you that thing should never be used in a training environment.
Trespassing into aircraft engineering here, but does not having a relatively short arm between CG and rudder make rudder design and sizing more critical? Look at a C150, the rudder is at least 0.5m further aft of CG compared to a Bristell. In other words, I would have thought The tighter the coupling distance between CG and rudder/elevator, the more critical the design of those control surfaces, but what would I know? I would also expect that the shorter “wheelbase” between rudder and CG leaves less time and room for error in spin recovery.
Because unless I’m mistaken, Lappin was commissioned by CASA to flight test the aircraft to assess its spinning characteristics.
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Because unless I’m mistaken, Lappin was commissioned by CASA to flight test the aircraft to assess its spinning characteristics.
