|
That explains why it wasn't upside down like most Vmca accidents.
|
Originally Posted by compressor stall
(Post 9722392)
That explains why it wasn't upside down like most Vmca accidents.
|
Originally Posted by Obba
(Post 9722385)
Basically says that both engines were running at the time of the crash.
Not necessarily. The core can still be rotating due to the aircrafts forward speed. See one of my posts on the previous page answering Eddie Dean. They also state that there was no evident pre-impact internal failures. There quite possibly could have been some external component that has failed resulting in a loss of power (ie fcu). (note, I am not stating any kind of hypothesis here, just trying to highlight what the terminology in the prelim report is saying). Like I said previously, the prelim report won't answer all the questions and we have to wait for a more thorough report after further investigation. All this has done is stated some known facts- not necessarily anything about the causal factors.. Spinex, you said it mate, more questions than answers. |
Damn, I guess all we get from this preliminary is that we don't know what happened yet. Clearly the pilot believed almost right away that he had a problem, and within 5 seconds events had caused it to begin rapidly loosing alt.
I don't know the accuracy range of the tracking data, but to my layman's eye, the tracked flight path by ADB seems to also rule out those early reports/speculations that the retail building was the cause/major contributing factor of the crash? I'm not saying building that there was a brain trust moment, just that looking at the VS numbers, and path, it seems that if that building wasn't there, it'd have just come down on the edge of or in the freeway cutting? |
Originally Posted by Car RAMROD
(Post 9722407)
Not necessarily.
The core can still be rotating due to the aircrafts forward speed. See one of my posts on the previous page answering Eddie Dean. They also state that there was no evident pre-impact internal failures. There quite possibly could have been some external component that has failed resulting in a loss of power (ie fcu). (note, I am not stating any kind of hypothesis here, just trying to highlight what the terminology in the prelim report is saying). Like I said previously, the prelim report won't answer all the questions and we have to wait for a more thorough report after further investigation. All this has done is stated some known facts- not necessarily anything about the causal factors.. Spinex, you said it mate, more questions than answers. FCU drive shear should go to full noise. Well on a - 20 and -34, maybe -41 and -42 have different arrangement. In my uneducated opinion |
preliminary report on Essendon accident
Statement on update: Essendon accident Update of ATSB’s investigation into the collision with retail facility involving B200 King Air VH-ZCR at Essendon Airport, Victoria on 21 February 2017. The ATSB has today released an update into the tragic accident involving a B200 King Air aircraft that collided with a retail facility at Essendon Airport on 21 February this year. Sadly all four passengers and the pilot died in the accident. ATSB Chief Commissioner Greg Hood said ATSB investigators have done an extensive amount of work to date. “Investigators have gathered and assessed a large volume of evidence such as CCTV footage and witness statements. The team has also inspected the engines in close consultation with the manufacturer,” Mr Hood said. “The aircraft’s fire-damaged CVR was retrieved and transported to the ATSB’s technical facilities in Canberra for examination and download. “While the CVR was successfully downloaded, no audio from the accident flight was recorded. All the recovered audio was from a previous flight on 3 January 2017. The ATSB is examining the reasons for this.” Mr Hood said that while the team is diligently assessing the physical and digital evidence, the considerable damage to the aircraft is presenting challenges. “The extensive damage caused by the collision and post-impact fire has meant investigators are yet to determine a clear picture of the causal factors behind the accident and loss of life,” Mr Hood said. “I offer my deepest sympathies to the families and loved ones of those on board the aircraft. Every effort is being made to determine the cause of this tragic accident.” This update does not contain findings. The ATSB will present the findings of its investigation in the final report, due out in around 12 months. Further updates will be provided if significant information comes to hand. If the ATSB identifies any safety issues during the course of the investigation, it will immediately bring them to the attention of relevant operators and authorities for safety action. Collision with terrain involving B200 King Air VH-ZCR at Essendon Airport, Victoria on 21 February 2017 |
http://www.atsb.gov.au/media/5772607...4_figure-1.png
source: atsb The ATSB said Airservices ADS-B data showed the aircraft reached a maximum height of about 160ft above ground level while tracking in an arc to the left of the runway centreline before colliding with the DFO shopping centre. The aircraft was configured with 10 degrees of flap and had its landing gear extended and locked when it crashed. The engines were taken away from the accident site for further analysis with assistance from the engine manufacturer. “That examination found that the cores of both engines were rotating and that there was no evidence of pre-impact failure of either engine’s internal components,” the ATSB said. |
Slash marks on the roof from the left prop would seem to indicate it wasn't feathered. Fag packet calcs of slash marks would seem to indicate normal RPM in 2,000 region. Some sort of failure in rudder boost? Any thing else to cause directional control issues?
|
My belief is that the Pel-Air matter will be further pushed aside while this matter is investigated. Serious as it is, the preceding matter has more concerning aspects to investigate, rather than be a back-squaddie or red herring.
|
Originally Posted by Eddie Dean
(Post 9722406)
please explain
Why it went left and not up, I don't know. With the lack of CVR, I fear that the final report will be inconclusive and we'll be debating the least implausible theories for decades to come. Hopefully lead Oxo-bromide doesn't feature. (*where an engine has failed and with the lack of performance, the aircraft trades height for speed until there is no rudder left to counteract the yaw and the aircraft rolls inverted, usually somewhere just off the end of the runway) |
Not directly related to the accident report.
WebTrak Above is a link to the noise monitoring data at Essendon airport. The archive includes the accident date. I note that the tracks of some aircraft appear at the beginning of the taxi or a hover. Other tracks don't appear until the flight is past the end of the runway. What method is used to derive the track? Why does the position of the commencement of the track vary between aircraft/flights? There is no track for the King Air, it seems to fit the category of tracking that does not commence until the flight is past the end of the runway. The decibel level of both the impact and post impact noises (explosions?) are recorded. Mickjoebill |
Eddie, if you fly PT6 gear, if you ever have the chance to shut one down in flight give it a go and have a look at your N1 (or Ng if you prefer that term)- there will be rotation. Been there, done that, and the sims replicate it too.
I'm working from memory here as I don't have access to my manuals right now, but the air start procedure (no starter assist) calls for a minimum airspeed to be reached. Do you know why? Well, in very simple terms, this is to force air into the engine and rotate the N1. Megan, even with failure of the rudder boost the B200 is very controllable. It is best thought of as an "assistant"- it doesn't give you a massive bootfull of rudder but rather just gives you a bit of rudder to help you out in an asymmetric situation. It's a 10 day item if failed so not exactly critical. If your calculations on prop rpm are anywhere near correct, that intrigues me. Comp stall, yes the lack of CVR is very disappointing, the investigation probably wont be able to uncover many useful facts as a result. One thing I find interesting from the report is the flap position. 10 degrees is not a correctly rigged position. If memory serves me right, the Takeoff/Approach (40%) position is 14 +/-1 degrees. |
At least Ch7,9 and SBS had a Swinburne academic on tonight who gave a sober, measured response. Yes, the engines were developing power. No, we don't know if that meant full power. No, nobody knows why the CVR was blank. Yes, many factors yet to be considered. And thank goodness the SBS guy clarified that Mayday 7 times does not mean 7 transmissions. Better this guy than GT any day
|
Ramrod, not flown one but thrown spanners at a few.
You have me thinking about airstart on fixed wing versus B212 which I have seen. On ground runs on King Air fuel is introduced at about 18% Ng so with an air start does the same apply? Do you just open the condition lever and pour fuel in or is it a proper start cycle? How do you latch the igniters without hitting the start button? Appears I may need to brush up on my theory a bit as been working on Jetrangers and light pistons for last few years. Cheers |
Curiouser and curiouser....:hmm:
|
Somebody mentioned friction locks a while back. I have spent most of my flying time on Beechcraft and cought out once by it just after lift off. Result would have been similar if it wasn't for my lightning fast reaction.
Got me thinking again....... |
Eddie, hmm those heli whirly thingies. No idea with that witch magic! But on the King Air there's a couple of different sets of switches.
One of them is the "Ignition and Engine Start" which spins the starter and provides spark at the igniters. This switch also has a position to motor the engine without ignition, but that's not relevant for this discussion. The other set of switches is is the auto-ignition. Without going in to too much detail, these are generally turned on before takeoff and off after landing. If for some reason torque drops below 400ft/lbs the ignition system will energise automatically, providing spark. These switches lever lock into the armed position. In a no starter assist start, basically have the auto ignition armed, be below 20,000ft and going at least 140ias, condition lever to low idle and monitor the start. Once stable, set power as required. Sms777, it was me who brought up the friction locks and power lever slide back. There are those pilots who have and those pilots who have not experienced it. And there's probably many, many more who have no clue as to it being possible. You have experienced it, so you know what it's like. In the King Air it'll more often than not be on takeoff when you take your hand off the power levers to grab the gear. I'd probably put money on this being what you had. Am I close? It isn't that difficult to deal with to be honest, but there is a very real possibility that someone somewhere could stuff it up and not realise what has happened. Out of this discussion, whether or not there is any relation to this accident, if some people have learnt about the phenomenon then that's good. |
No cvr recording, but obviously working on prior flight. Both engines showing no signs of pre impact failure.
Very odd. |
Both engines showing no signs of pre impact failure. |
The following from a tin foil hat wearing , conspiracy theory sprouting mate , suggesting I google,
" Munsch Hardt Lawyers, bankruptcy, Enron, and Northwest Airlines " Supposedly this would produce a theory for why the crash occurred. Beyond my tolerance level I'm afraid. Can any Pruners decipher this babble? |
Does the Kingair have external flight control locks?
Not insinuating anything - just interested. |
441 - nope, nothing genuine/approved anyway. I suppose someone could make something up, but why?
Never seen any with external locks either. |
Originally Posted by mickjoebill
(Post 9722548)
Not directly related to the accident report.
WebTrak Above is a link to the noise monitoring data at Essendon airport. The archive includes the accident date. I note that the tracks of some aircraft appear at the beginning of the taxi or a hover. Other tracks don't appear until the flight is past the end of the runway. What method is used to derive the track? Why does the position of the commencement of the track vary between aircraft/flights? There is no track for the King Air, it seems to fit the category of tracking that does not commence until the flight is past the end of the runway. The decibel level of both the impact and post impact noises (explosions?) are recorded. Mickjoebill |
Wrong fuel, contaminated fuel and/or water in the fuel.?
|
What about weight and balance issue/shifting of golf bags during takeoff?
|
1 Attachment(s)
Car RAMROD, I'm presuming these are the prop slash marks.
|
Would anyone know what bus the CVR is powered by? What other systems might be on that bus if for whatever reason it failed/was not energised...?
|
Originally Posted by megan
(Post 9722500)
Slash marks on the roof from the left prop would seem to indicate it wasn't feathered. Fag packet calcs of slash marks would seem to indicate normal RPM in 2,000 region. Some sort of failure in rudder boost? Any thing else to cause directional control issues?
How ever damage between B and C flange is an indication of Tq on inpact but i have yet to see a clear photo of ethier engine. |
Originally Posted by Eddie Dean
(Post 9722471)
fairly sure Ng will go to zero if engine is shut down. Np will do whatever the prop is doing.
FCU drive shear should go to full noise. Well on a - 20 and -34, maybe -41 and -42 have different arrangement. In my uneducated opinion |
Really you can tell the prop was at 2000rpm |
Originally Posted by megan
(Post 9723395)
Simple, four bladed prop, ATSB gives the GS just prior to impact, measure the distance between prop strikes, and apply a bit of maths.
|
In the report, ATSB listed flap setting as 10°. Is this the same as approach flap setting in the B200 which according to my manual is 40% of total flap extension. I can't seem to find actual flap settings in degrees in any B200 training text or AFM.
Also, why would the pilot use flaps approach on runway 17 at YMEN? Looking at TODR I wouldn't have thought there would be any runway length considerations to warrant such flap setting. |
Originally Posted by Obba
(Post 9722385)
Basically says that both engines were running at the time of the crash.
|
Manymak, already mentioned the flaps in a previous post buddy.
T/O App (40%) flap setting is 14 (+/- 1) degrees. Taking off with flap is better. Have a look at many of your performance figures, especially for Raisbeck equipped machines and the equivalent FAR25 numbers. |
Originally Posted by Car RAMROD
(Post 9723539)
Manymak, already mentioned the flaps in a previous post buddy.
T/O App (40%) flap setting is 14 (+/- 1) degrees. Taking off with flap is better. Have a look at many of your performance figures. But at some point if runway length is no problem. Takeoff without flap is more desirable. Have a look at Raisbeck accelerate go distance required charts and see the performance penalty an engine failure at V1/Vr to 35' incurs with flap approach. |
Originally Posted by Car RAMROD
(Post 9723539)
Manymak, already mentioned the flaps in a previous post buddy.
T/O App (40%) flap setting is 14 (+/- 1) degrees. Taking off with flap is better. Have a look at many of your performance figures, especially for Raisbeck equipped machines and the equivalent FAR25 numbers. |
Yes that's true the 2nd segment isn't as good.
But you also get better margin over stall and Vmca with flap at T/O. As long as the numbers work, my preference was with flap. |
In 2,500hrs of operating the B200, I not once took off with approach flap, unless I was clearly in need of it (obstacle clearance take off).
If you suffered a donk failure, you're going to want to clear those obstacles, not reduce your ground roll on a runway where you're already only using like 1/3 of the runway. A colleague I was talking to one day who operated the King Air and used approach flap for take off, went to Flight Safety for a course on the King Air. They showed him the climb penalty for taking off with approach flap. Needless to say, he never took off with approach flap again! morno |
Hear hear Morno! Over 3000hrs on type and I completely concur!
We look at it in the sim and it's a significant point of discussion (along with demonstrating on P charts) with pilots new to the type too! |
If ever I am in the position where I must use an APP Flap take off, I am never comfortable until the flap is retracted. Minimum airspeed, flap and gear extended, windmilling prop, is not a place I would ever like to be in a Kingair!
|
| All times are GMT. The time now is 09:22. |
Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.