2000 rpm to 1586 rpm big difference. Please explain as you said it hit at 2000 rpm simple math you said. Difference is one being governed and one not. Nearly 25% not worried about a any ones elses reading as its not a point im trying to make. With out accurate measurements and not some pics its impossible to get it right. Its pure speculation as to prop speed. If it was simple maths we would not have 3 different answers aready.

P3 / px pre fcu Py post fcu ie py to gov and tq limiter on th -41/42

Left and Mick, unable at the moment to find the source of where I found the roof cladding info.I see the Kliplok here says 233mm between ridges. Do different manufactures have different profiles?

Roofing Profiles | Select Metal Roofing

Seems to be an avenue closed, unless some one can climb up there with a tape.Unfortunately Eddie pending failures don't always show up on preflight. Have experienced three governor failures. The best was multi engine helo and during cruise the TQ's started surging. As one engine ran up the other ran down and visa versa. Playing semaphore over a wide TQ range. Identified the bad engine, reduced to idle, motored home, and gave it to maintenance.

Aircraft returned to line, and I made a big, big mistake in not checking what work had been carried out exactly. 35 minutes into the next flight in cruise the previously bad engine dropped to zero TQ, hand was half way to grabbing the throttle to reduce it to idle, when in the blink of an eye it went to max power. I couldn't believe the acceleration, far faster than a slam acceleration, and I was surprised it did so without any sign of compressor stalling. In any event, reduced power to idle and motored home. That's when I found the remedial action from the previous event was they made a one hour flight and unable to fault. Cause was deemed to be stricture in the flywheel assembly causing the original TQ fluctuations, which ultimately led to drive shaft failure on the final flight.

Flying a single engine type making approach to home base. Went to pull collective to terminate to the hover and there was nothing there, as in no engine response. Landed off an auto rotation, placed the governor into manual fuel and hovered to the pad, put the governor back into operation and unable to fault.

Dual engine PT6 helo, had just landed and both throttles still full open when one engine slowly started to accelerate with attendant increase in rotor RPM. Placed governor into manual fuel and completed flight. Maintenance put down to slug of ice in the P3 line.

Yes, they do and even the same manufacturer has different profiles for different products. Bluescope/Lysaught have a range of products such as SPANRIB, TRIMDEK, LONGLINE, INTEGRITY and FLATDECK all with varying profiles. You've then got a range of aluminium-based roofing products as well.

I struggled with trying to determine exactly what roofing product we were looking at too but as I mentioned earlier I think that the alignment with the HVAC ducting and the walkways is instructive.

Investigation: AO-2017-024 - Collision with terrain involving B200 King Air VH-ZCR at Essendon Airport, Victoria on 21 February 2017

The shipping container in one of the photos would be about 2435mm wide. The container is roughly aligned with the roofing ridges. Might give you a ball park figure to work with.

Came across this AAT decision published a few days ago regarding the situation

Australian Corporate Jet Centres Pty Ltd and Civil Aviation Safety Authority [2017] AATA 403 (31 March 2017)

The flight was 9 seconds from airborne to crashing and 7 Mayday announcements were made by the PIC. That is concerning in itself.

Correct you are. Amended post to remove ambiguity

Good call Short Field! My guess is that ACJC is now toast. The Americans will sue them to bits. They are effectively out of business all ready - even if they win the case, the legal costs will bankrupt them.

The case of ACJC, if it goes to trial, is going to be analogous to the famous insurance case where a an item of ships Cargo was dropped in the water between the ship and the wharf while being unloaded and neither insurer would accept responsibility.

What a clusterf*ck. All over a $65 CASA fee.

I reckon around $65,000 will have been p*ssed up against the wall on bureaucratic busywork, lawyers and the AAT's time. :ugh:

You're new here so, I'll be nice. It's not speculation, it's estimation.

And the maths is simple, it's year 7 level. We have two different answers (not three) because we have two different estimates of the distance between the prop strikes. I think megan now sees that her original estimate was on the low side because her reference measurement was on the high side; that means that you can discard the original estimate of 1586 rpm. So now you have one estimate that is within 6.7% of 2000 rpm; that's not bad given the method of estimation, moreso when we can see that the prop speed is retarding at about 4% per completed rotation as it chewed its way along the roof.

It is worth noting that 300mm between the roof cladding ridges is the largest distance likely and based on that we get an average left prop rotation of around 1866 rpm. That speed is in the green arc. If the ridges are closer than 300mm then the estimated rpm goes up, not down.

Connedrod "new here"? That right there is funny. :}

On a serious note, I still don't understand why a yaw to the left would have been caused by a left engine/propellor that seem (on the extrapolations from the best guesses as to the dimensions of the prop damage to the roof) to have been running normally, irrespective of what came first out of the yaw and falling below VMCA.

If we assume there was some catastrophic failure and the pilot was deliberately turning left to keep some runway in sight while the left engine/propellor were operating normally, how does a left yaw result from that or falling below VMCA?

Maybe the extrapolations from the best guesses as to the dimensions of the left prop damage to the roof are incorrect.

It was actually the opposite, the new AOC holder wanted the Registered owner/ operators details reverted to MyJet. For obvious reasons.

Ref your thoughts on the yaw, Ramrod's explanation of auto feather and others' thoughts of it being disarmed could lead to this occurrence.

Sunfish, unless maintenance has been carried out under the current AOC they may not bear any responsibility at all.

Lead, have a google for the report on the crash of VP-BBK.


Edit, I see Megan has posted it below.

Megan, I only mentioned the power lever slide originally only to highlight the phenomenon to any drivers that might not be familiar with it. I never meant for it, and I still don't mean it to, imply anything to the crash of ZCR. There's a handful of other ways any plane can kill you.
I'm happy to discuss generalities and B200 technicals, observations based on my own experiences etc, but I'm not posting my own thoughts/beliefs as to any causal factor of this crash. That's for the investigators to publish. The lack of CVR data is disheartening though and going to make the investigation that much more difficult.

Time will tell, but there are uncanny similarities of this accident to the following, notably power reduction in the left engine and loss of RPM, but not an engine failure per se.

https://dms.ntsb.gov/pubdms/search/h...6E4D369AA7935E

https://assets.publishing.service.go...pdf_022814.pdf

Read, and draw your own conclusions.

As with these two reports, I don't see the ATSB coming up with any definitive answer, other than an assumption of possible Power lever migration, which Car RAMROD mentioned back at post #106. As I said, time will tell.

"Opposite" of what?

The reasons ACJC doesn't want to appear as the registered operator after the accident are, as you say, obvious.

If you read the AAT's decision you will see that before the accident ACJC was agitating CASA to find out why ACJC had not become the registered operator in accordance with an application submitted in December 2016. Indeed, ACJC's most recent inquiry to CASA was the day before the accident - 20 Feb.

On my reading of the AAT decision, the only reason the application had not been processed to completion in January in accordance the registration holder's wishes and ACJC's signed consent was that the registration holder's $65 credit card authorisation 'bounced'. The amount was then paid and the application actioned on 16 Feb. ACJC found out about this on .... 21 Feb.

For both of those accidents, the aircraft had just come out of maintenance that likely involved the adjustment of the throttle friction.

For the Wichita crash, the maintenance was followed by two short post-maintenance test flights, then came the accident flight.

For the Blackbushe crash, the maintenance and associated ground runs were immediately prior to the accident flight.

Any maintenance to ZCR immediately prior to the accident flight?

Understood RAMROD, as I said you mentioned it, I'm not implying that you thought it causal in this instance, I sincerely hope it's not read that way. But after reading the two reports I do think it has merit by way of explanation - my opinion only.

Megan, sometimes I don't conmunicate entirely effectively so I can see how you may have thought I was replying directly back to you as such. My response was more for others reading your post about what I had said. Some people may have believed what I had previously stated, which you had mentioned, could be me inferring a causal factor.
I think you and I are understanding each other though.


FGD, whilst maintenance was obvious in the Blackbushe and Wichita accidents, as I'm no doubt sure you'd know the frictions could be adjusted for other reasons (another pilot flew the aircraft previously for example).

Mmm ... I was working off the little "I'm new here" sign and a joined date of March 2017. What am I missing?

Ummm 2000 rpm WAS given 1st then revised to 1586. It WAS not given as an estimate as it WAS ginen as 2000rpm. Funny thing is you cant even agree on the size of the corrugations in the roof sheeting. The only thing that is true is the prop rotational speed WAS between 0 and 2050 rpm. And btw with your estimate it is 3 different speeds.
You clearly dont understand how the egine in question works and the difference of that 25%ish means to the outcome of this investigation.

If the estimated prop speed is correct then it will be above the min auto Tq range, hence no auto feather.

Also if these estimates are correct for higher rpm you can forget about the power lever roll back.

Not necessarily. Quote below from the Blackbushe accident.


Hypothetically speaking, a "higher" RPM could have come about from realising what the problem was, and the lever pushed forward again but by then it was too late to recover.
This was possible in the Blackbushe accident, with final derived prop speed about 2125rpm.

At 2050 rpm ish the O/S gov will take ovér prop pitch. Any over tq will dump fuel from the fcu via py from the tq limiter.

The 2,000 was my original estimate, and if you had been reading everything you would see that I said I amended the figure because of incorrect measurement in the first instance. You need to read everything, and not cherry pick. I explicitly said in the amendment "Error made in measuring distance in original post".

What part of your own sentence don't you understand? I was going to say, "You do know what a revision is, don't you?" but thought the better of it on the basis that so far you've struggled with primary school maths and spelling.

Really?! 2050 rpm?! That level of precision is simply outstanding! By what method did you come up with that number as being "true" no less?

Gee, I wish I'd said that. Oh, wait, I did.

Mmm ... no. As a matter of fact, as Car RAMROD pointed out, a very high rpm would be entirely consistent with an attempt to correct a power lever slide (not roll) back.

On that point you are most assuredly correct, near as I can tell Egine is an Armenian-born pop singer. Where does she fit into this?

You clearly have a problem with primary school level maths and spelling and you don't or can't understand concepts like estimates and revisions yet you seem intent on parading your ignorance as a virtue in some sort of inane attempt to promote yourself as big man on campus. What's that all about, hmm?

Geez and I thought LB was being a bit harsh on me over on the AFIS thread! :ouch:

Cherry picking? No... you revised that only after i challenged you on that that, your reply was simple maths, down to 1586 rpm. How many goes do you wish to have. So no not cherry picking at all. Just useing your own words and figures. Two different engine parameters i cant empress this enough.

The Age - Not our pilot: Legal battle over DFO crash plane (Company told hours after Essendon DFO crash that plane was in its name)

The aviation company potentially facing a multimillion-dollar lawsuit over the Essendon DFO disaster was told three hours after the crash that the plane involved had been registered in its name.
...
Emails published in a finding by the Commonwealth's Administrative Appeals Tribunal show the company did not find out its application to transfer registration had been approved until midday on February 21 – three hours after the crash at 8.58am.


"Your application was actioned ... it should be on its way in the mail," CASA wrote in the email sent at 12.01pm.
...




Company told hours after Essendon DFO crash that plane was in its name

So, the day before the crash, Aus Corporate Jet Centres asks CASA "Are we the registered operator yet? We've applied yonks ago", CASA says "Yep, it's yours" and now they're saying "Nothing to do with us - someone else was flying "our" plane under his AOC, business name, etc etc..."

If it wasn't their plane, why the second application to transfer the registration into their name? Why the follow-up email? Which now begs the question: Who actually did own this million-dollar aircraft, if ACJC applied to have it as theirs but says "But but but it wasn't our plane"

And people wonder why the industry is in such a state?

Makes me wonder if CASA will now have a good look at ACJC and their administration given that "their" plane was flown by someone who - apparently - had nothing to do with them, in a commercial operation, and just how often this kind of thing goes on....

Not quite....CASA said "it's yours" after the aircraft had crashed.

I dunno, I think that is just a reply to ACJC's email asking about their application. If they hadn't followed it up, they would have got the letter in the mail dated Feb 16, 5 days before the accident. Just because they found out after the accident doesn't gel with their application that seems to have been actioned 5 days before the accident.

Who the owner happens to be and under whose AOC an aircraft may or may not be operating at a particular time are irrelevant matters to the question as to who had registered operator obligations under the regulations at that time. On my reading of the AAT decision, ACJC was the registered operator at the time of the accident.

Interesting... so it appears that the registered operator is appointed by the owner (without any description of the form that must take?), and any cancellation/appointment takes effect as decided by the owner, not upon acceptance by CASA.

The owner is only required to notify CASA within 14 days of any change.

So then the question might be:
What responsibilities do the owner and registered operator respectively have, if the owner allows someone to operate the aircraft without the knowledge and approval of the registered operator?

Also, if the owner allows or asks someone else to perform the duties of the registered operator after the date the registered operator was changed, could that be considered another (defacto) change of registered operator? (A stretch perhaps, but I suspect there will be a few interesting arguments put before this is ended.)

Your only concern was airspeed, which has absolutely nothing to do with the issue. You asked,andMy original error of 2,000 was brought about by measuring the distance over four slash marks, rather than the correct five. Brain fade on my part.

Yes, this kind of statement does indeed sound a lot like our old friend, "yr right".

If we were left in any doubt, there was also this statement:

I, too, was interested to read Eddies post but not that he "can't/won't tell" due to "secret squirrel business"
If the evidence provided by eye witnesses is given to the ATSB and they weigh it up, then it may be present in the final report which will be available to everyone to read.

Anyhow, What could an eye witness see during the takeoff run that would point directly to the accident cause? My conjecture only.

• Smoke/Flame from a failing engine
• Unusual engine sound
• Split flaps
• Open door/hatch
• External control lock still in place
• Something else??

I'm very hopeful that the ATSB will get to the bottom of this so that we can all learn from it.

No not at all. I was amazed that you could detrime that the prop was at 2000 rpm from what little evidence was aviable at the time. You said simple maths was your answer. Well clearly not at you then changed your next estimation by nearly 25%. Which as i said places the engine into two completely different parameters.
One which would be considered makeing power and the other not.

You cannot tell from RPM alone whether the engine is "making power". Positive torque would be a more correct term for this, by the way.

To determine whether positive torque existed or not requires knowledge of the RPM and the propeller blade angle.

It is self evident that the torque produced by the L engine was a very low value. Possibly positive, possibly negative.