Crash at SunShine coast.

[djpil]

Originally Posted by Beryllium Erbium

As a C150 Aerobat owner, I didn't do any aero's or spins in The Bat until this report came out. As is the case when an accident of this sort happens, you chat to your aerobatic mates about possible causes. ....

Yes, good to be cautious. Trouble with being an engineer if I have to sit flying S&L for too long I start wondering about particular bolts and attach fittings etc. I've learnt to avoid chatting to most aerobatic mates early on as they jump to conclusions and mislead me. The ATSB is pretty good at alerting us about defects fairly quickly.

Originally Posted by 43Inches

Where I worked many years ago we had 5 152s, 3 of them aerobats. One of the Aerobats VH-RYI flew differently to the others, seemed to have slightly different attitudes and a bit more aggressive stall characteristics. We had the rigging checked numerous times, and found nothing different to the other two. ....

BMB was my favourite A152. HEZ was at the bottom of my list but it has been improved and I like it now. UPS was my favourite A150 then suddenly it changed its behaviour in snap rolls and spin entry - rigging measurements within tolerance but it had a section of wing leading edge replaced - sometimes it doesn't take much.

[43Inches]

NKJ on the right was a "texas tail dragger" converted back to a nose wheel, still had the forward wheel mounts.

[jonkster]

Originally Posted by djpil

Over the years I've had a number of spin instructors tell me about delayed recoveries in a Decathlon and I ask about their recovery technique - invariably I respond with "you were lucky that you didn't die" and refresh them on the correct recovery method amply described in the manuals.

I have always been curious about the Citabria and Decathlon POH's (at least the old ones I have). In the POH they state it should be placarded for the spin recovery technique and the placard technique is different in order from the emergency procedures section in the POH for spin recovery.

The placard has rudder application before neutralising elevator and the emergency section has elevator prior rudder.

I also would be curious to hear what technique was being used when the spin recovery was reported delayed in the Decathlon? MB?

[djpil]

Originally Posted by jonkster

I have always been curious .....

Yes, at MB. I've got this hypothesis that some-one looked at the Day VFR Syllabus many years ago and added what seems to be the appropriate control as I have done in upper case below.
"• Closes throttle
• Stops yaw RUDDER
• Unstalls wing" ELEVATOR
So text like that is in the briefing slides in the format of PARE. The presenter simply says the words on the slides so the briefing ends up something like full opposite rudder to stop the spin and then elevator to unstall the wing. This video demonstrates that nicely

You Tube

It seems to me that very few bother to read the manuals (I must admit to only reading the manual for my car when I can't get something to work).

The NZ CAA uses PARES rather than PARE - good idea I think to remind pilots that S (to stop the spin) only comes after both the R and E.

Even current production Super Decathlons have the old-style manuals, not much has changed since it was certified in the '60s. That was before the FAA permitted unapproved data in the AFM - so there is no POH per the GAMA spec. There is the approved AFM which takes precedence and the manufacturer's Pilot's Operating Manual. The emergency section of the POM suggests that elevator is moved prior to the rudder, as you say. In the normal operating procedures section it has text identical to the AFM "Recover with positive movement of stick to neutral and full opposite rudder." Words are in the opposite order to the placard and my interpretation (not just mine) is that it means simultaneous application of rudder and elevator. I ignore anything in the POM which is contrary to the AFM.
Important thing is not to apply elevator before the rudder. With instructor trainees I make a point of doing the PARE actions in that order but so quickly that the trainee believes that they were simultaneous actions - then this discussion.

[john_tullamarine]

David makes reference to the GAMA style POH. The current revision of GAMA Spec 1 can be downloaded from the GAMA site GAMA Technical Publications - GAMA and is worth a read for the younger set.

Prior to the original document in 1975, we had a dreadful mishmash of often not very useful manuals for light aircraft. Without digging into my really old and dusty filing cabinets to check, the first issue was very similar to an equivalent ICAO publication - can't recall at the moment which predated the other but that's probably not all that important. The document introduced a much needed change for pilot reference documents. My only hobby horse is that the weight and balance section is dreadful, but that is the prerogative of old chaps like Dave and me (I'm just slightly the more handsome but he still has his hair so I guess we're on a par).