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They did far worse to Jabiru with zero consequences to the bureaucracy. 

"Ethics and CASA" is like "military intelligence"

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The link in the AOPA article is pretty damming if you have the hour to read through it, Bristell and their agents have pulled some major shonkies along the way and CASA are just bringing them back in line.

 

https://aopa.com.au/wp-content/uploads/2021/03/Submission-to-CASA-Edited-for-Distribution_Redacted.pdf

 

I feel the AOPA article just cherry picked what it wanted from the CASA stuff to grind the axe with RA-Aus and CASA

 

From this site i can see at least 15 fatalities in this plane alone  tinyurl.com/yjxapmqe   not the 3 stated by the manufacturer

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if you couldn't see them then you must have been reading a different document to the one I was reading ?

 

Examples were from memory,

 

Declaring ASTM compliance before any spin testing was completed on that model of aircraft, and continuing to declare compliance for four years until spin testing was completed. This was acknowledged by the respondent as an oversight ?

 

Declaring ASTM compliance for aircraft that did not meet payload requirements in the LSA category (e.g. they are too heavy) Affected four or five aircraft from memory

 

Signing documents to declare compliance without validating that any of the compliance had been met on new models or new variants of those models which required revalidation before they could be sold as LSA compliant.

 

it was interesting reading even though a lot of the things the same over and over again.  To me it shows that self compliance may not be the answer to everything because manufacturers/distributors/agents can still make honest mistakes or make mistakes that are to the benefit of the manufacturer.

 

Claiming just a couple of fatality's around the world is quickly shot down by quick Google search. It makes you think if they are lying about things like this what else are they lying about ?

 

I won't comment further about this, it is really none of my business or interest, it is just that I found reading the document while waiting for my Covid shot was interesting and enlightening to see how this stuff works behind-the-scenes

Edited by FlyBoy1960
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It is interesting because Bristell is still on my list of possibles and if they are wrongly disparaged (as Jabiru were) then they may become a great value buy.

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1 hour ago, pmccarthy said:

It is interesting because Bristell is still on my list of possibles and if they are wrongly disparaged (as Jabiru were) then they may become a great value buy.

They will be great value either way. Just make sure you don’t stall. 

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The issue with the Bristell from what I have read in the docs put forward by the manufacturer (link in the first post in this thread) is actually clear in the letter from the Australian owner:

 

"With 2 stages of flap still extended _______ then demonstrated the effect of commencing a slow pull back of the stick, which was released as the nose rose. The stick continued to move backward by itself until stall occurred, after which the nose dipped accompanied by slight right-hand wing drop, followed by a second rise of the nose. It was necessary to firmly ease the stick forward to unload from the stall to regain straight and level flight."

 

For a plane that is certified I do not expect ANY of the flight envelope to include allowed loadings where the stick continuing to move backwards after the pull is released ... the fact that you had to firmly ease the stick forward to unstall adds to my eyebrow raised condition.

 

Add to that that the reported behaviour in all stalls was a mild/moderate wing drop and I would have thought that the combination of these was not absolutely what you expect in a factory airframe.

 

Now in saying the above I make no comment on compliance with the ASTM requirements - you can read the graphs yourself in other attachments linked to the submission to CASA to form your own opinion on just how close to unacceptable several of the variants are on the manufacturers own documentation - BUT if I were still an instructor AND I was faced with an aircraft that did not have stick forces positively returning to trimmed when stick is released I would personally be looking at a different airframe for ab initio training.

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Anything I've read makes that kind of stick loading an absolute No No for being airworthy. Further  control movement MUST require extra effort and be progressive manageable by a normal pilot (without special training or adaptive skills).. Nev

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20 minutes ago, facthunter said:

Anything I've read makes that kind of stick loading an absolute No No for being airworthy. Further  control movement MUST require extra effort and be progressive manageable by a normal pilot (without special training or adaptive skills).. Nev

Also such is part of the flight test for newly built RAA since 2016 when Tech Manual 4 started, don't recall the page within the document flight test record.

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I am no expert but that description of Bristell oscillation with flaps down sounds like neutral longitudinal stability, however the maths of stability and control does my head in. However i’m not sure that such a condition is disqualifying at close to 1.2 - 1.3 Vs.

 

The C172N has something like that mentioned in the POH in side slips.

Edited by walrus
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It may just be interference. Airflow over flaps affecting the elevators. That may or may not be a serious issue. I think the Victa's have a restriction on the last notch of flap.   Nev

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Just watched a Youtube video of the factory test pilot demonstrating stalls in a Bristell. By his own words each recovery took of the order of four hundred feet and the video shows a wing drop on each stall.

 

400' is too much compared to the GA standard for a C172/ PA28 of one hundred feet altitude loss. Such a loss also means that an error in recovering the dropped wing at circuit height is going to be fatal because it will delay recovery if not stimulate an incipient spin.. In my opinion and I'm not an expert, this is not an ab initio trainer by any stretch of the imagination.

 

 

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what amazes me is that people don't do stalls at a real throttle setting. Doing stalls at idle is a waste of time because the aircraft are normally behaving  at their levels of best behaviour. When my original training was done stalls were always performed at about three quarters power setting and sometimes at full power setting because that is when you are normally going to get bit. When you are climbing out and trying to get over some trees ahead of you or something like that.  Stalls at idle really don't simulate real-life stalls. I would like to see a video of stalls at let's say 5000 rpm or higher. I think then we can get a better idea of the aircraft's stall behaviour

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16 minutes ago, FlyBoy1960 said:

what amazes me is that people don't do stalls at a real throttle setting. Doing stalls at idle is a waste of time because the aircraft are normally behaving  at their levels of best behaviour. When my original training was done stalls were always performed at about three quarters power setting and sometimes at full power setting because that is when you are normally going to get bit. When you are climbing out and trying to get over some trees ahead of you or something like that.  Stalls at idle really don't simulate real-life stalls. I would like to see a video of stalls at let's say 5000 rpm or higher. I think then we can get a better idea of the aircraft's stall behaviour

Agree, do it at next bfr or before. Done at my last bfr.

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The "Usual" "close throttle and maintain height" is just a box ticking exercise. Pilots being $#1t scared of stalling is justified by their ignorance of what's really involved. Be wary is OK but scared is not helpful at all when you are supposed to be reacting correctly. The normal pilot reaction to the nose dropping is to pull the stick back. To a wing dropping is to lift it with aileron. You need to be educated out of those natural reactions.. A more realistic approach has been required since the spin capable planes went missing in the early 60's. It  is close to criminal neglect to not address this issue properly.  Even benign and hard to stall types can bite at times  Nev

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Strangely the UK BFR for microlights on trikes requires demonstrated recovery from a climb power climbing turn stall ... and as they cannot spin but will spiral like you would not believe your responses HAVE to be instantaneous and you have to handle them correctly because you can overspeed the airframe to failure speeds very quickly ... nobody likes literally pulling the outer wings off a trike in flight BUT that is the real risk that we were all trained for and regularaly tested on handling.

 

And people wonder why older UK pilots tend to migrate towards three axis and give up on weightshift 😉 

Edited by kasper
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In some planes a spiral can be more dangerous than a spin because of airframe limitations. You can spin forever (height permitting) but if it becomes a spiral the speed and dynamic load will keep increasing and quickly you may be subject to airframe failure. As far as I know spiral demos and training are NOT permitted in RAAus aircraft (3 axis.).  This does pose a problem for skills basing pilots.  Nev

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What schools are you guys going to?

we did;

Full flap power off stalls

full flap power on stalls

clean stalls power on

clean stalls power off

power on climbing stalls

power on climbing turn stalls

simulated wing drop in stalls - ie if the plane wouldn't do it, the instructor made it do it.

basically any airframe set up and then stall it - some of those are not pleasant experiences.

I"m not scared of stalling, but still very mindful of airspeed and attitude when doing turns in the circuit.

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On 28/03/2021 at 10:49 PM, walrus said:

Just watched a Youtube video of the factory test pilot demonstrating stalls in a Bristell. By his own words each recovery took of the order of four hundred feet and the video shows a wing drop on each stall.

 

400' is too much compared to the GA standard for a C172/ PA28 of one hundred feet altitude loss. Such a loss also means that an error in recovering the dropped wing at circuit height is going to be fatal because it will delay recovery if not stimulate an incipient spin.. In my opinion and I'm not an expert, this is not an ab initio trainer by any stretch of the imagination.

 

 

400 feet by a *factory* pilot AND the stick forces are wrong!? And it’s legal to fly at 500 feet over unpopulated areas, right? If the above is even half true it does not look like CASA will be on a witch hunt no matter what they do. 

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On 18/03/2021 at 12:03 AM, pmccarthy said:

I am surprised at that, to say the least. Got a problem with a plane? Hire a test pilot to examine it. Simples. Or am I missing something? 

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AOPA/Ben Morgan does a lot of good for pilots and aviation in general, but he seems to have RAAus in his sights and take any opprotunity to have a go at them.

It does seem he's cherry picked that report. 

Maybe CASA and RAA should have done a bit more work before going heavy on Bristell, but there does seem to be some valid concerns.

I'm curious whether the Relationship between AOPA and RAA was better before RAA registered the "Freedom to Fly" slogan. That was a bad move on their part.

Or has there been angst between them for some time.

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