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King Air down at Essendon?

Old 3rd Apr 2017, 09:40
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Originally Posted by MickG0105
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.

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.
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Old 3rd Apr 2017, 09:53
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If the estimated prop speed is correct then it will be above the min auto Tq range, hence no auto feather.
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Old 3rd Apr 2017, 10:15
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Also if these estimates are correct for higher rpm you can forget about the power lever roll back.
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Old 3rd Apr 2017, 11:03
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Originally Posted by Connedrod
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.

Power lever migration
Tests were carried out, both on the ground and in flight, to examine power lever migration with the friction selected fully off. Take-off power of 2,230 ft lbs was set and 2,000 propeller rpm (governed) was selected. When the pilot removed his right hand from both power levers on the ground, they migrated aft initially very quickly to 1,000 ft lbs and then more slowly with the torque falling to 400 ft lbs. The left propeller lever moved more rapidly aft on each occasion and on different test aircraft. This was possibly due to the fact that the control cable to the left engine is shorter and subject to less friction than the cable controlling right engine.
On the ground when the power lever moved the propeller rpm reduced immediately to 1,900 rpm but then fell further to 1,600 rpm. In flight the left propeller rpm reduced to 1,800 rpm with the IAS at 110 kt representative of the speed at which the accident aircraft rotated from the runway and the speed at which the propeller rpm was seen to initially decay.

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.
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Old 3rd Apr 2017, 11:23
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Originally Posted by Car RAMROD
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.
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Old 3rd Apr 2017, 11:49
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2000 rpm WAS given 1st then revised to 1586
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".
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Old 3rd Apr 2017, 13:03
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Originally Posted by Connedrod
Ummm 2000 rpm WAS given 1st then revised to 1586.
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.

Originally Posted by Connedrod
The only thing that is true is the prop rotational speed WAS between 0 and 2050 rpm.
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?

Originally Posted by Connedrod
If the estimated prop speed is correct then it will be above the min auto Tq range, hence no auto feather.
Gee, I wish I'd said that. Oh, wait, I did.

... it is reasonable to infer that the left engine was producing more than 200 foot-pounds of torque otherwise the auto-feather system would have opened the dump valve and feathered the prop.
Originally Posted by Connedrod
Also if these estimates are correct for higher rpm you can forget about the power lever roll back.
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.

Originally Posted by Connedrod
You clearly dont understand how the egine in question works ...
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?
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Old 3rd Apr 2017, 14:36
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Geez and I thought LB was being a bit harsh on me over on the AFIS thread!
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Old 3rd Apr 2017, 21:11
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Originally Posted by megan
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".
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.
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Old 3rd Apr 2017, 22:40
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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
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Old 3rd Apr 2017, 22:58
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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....
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Old 3rd Apr 2017, 23:08
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Originally Posted by KRviator
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.
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Old 3rd Apr 2017, 23:12
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Originally Posted by Stikman
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.

Civil Aviation Safety Authority records show Australian Corporate Jet Centres became the registered operator of VH-ZCR on February 16, just five days before it went down.
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Old 3rd Apr 2017, 23:37
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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.
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Old 4th Apr 2017, 01:53
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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.)
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Old 4th Apr 2017, 02:01
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you revised that only after i challenged you on that that
Your only concern was airspeed, which has absolutely nothing to do with the issue. You asked,
Fwd airspeed at impact was
and
So over 24 hours has passed and you still not answered the question of fwd airspeed.
It is impossible to make the statment that the prop was at 2000 rpm with out knowing the airspeed to make the statement as fact.
My 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.
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Old 4th Apr 2017, 05:11
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Any over tq will dump fuel from the fcu via py from the tq limiter.
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:
You clearly dont understand how the egine in question works...
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Old 4th Apr 2017, 06:20
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Originally Posted by Squawk7700
Do tell more..... flaps, reduced power? Am trying to think what else would be noticeable from the takeoff roll... ATSB did say that it was a longer takeoff roll than normal.
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.
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Old 5th Apr 2017, 20:47
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Originally Posted by FGD135
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:
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.
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Old 6th Apr 2017, 01:35
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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.
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