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AW139 incident - Houma

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AW139 incident - Houma

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Old 30th Sep 2022, 10:27
  #41 (permalink)  
 
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That is the case for the cockpit windows, the cabin windows are pushed out
Thanks Nescafe
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Old 30th Sep 2022, 19:24
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A helicopter cockpit emergency egress door or window that could to be pulled in? Where are you going to put the darn thing?
Kinda counter intuitive.
Jettison one in forward flight? Regardless of which side the tail rotor is on stranger still.




Originally Posted by SASless
The window was pulled inwards....not jettisoned to the outside according to some reports I. have seen.

What I took from the wording is there might have been a bit of rough treatment of said window in the process of getting some beneficial use of the opening in clearing out the smoke and fumes.

Which....seems very reasonable and understandable if the window was extremely small and wanted enlarging.



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Old 30th Sep 2022, 21:14
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I am betting the Door is jettisionable...not the window......perhaps a 139 knowledgeable person can address that for us.
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Old 30th Sep 2022, 21:19
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I am betting the Door is jettisionable
No, neither cockpit nor cabin doors can be jettisoned.
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Old 30th Sep 2022, 23:19
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Originally Posted by albatross
A helicopter cockpit emergency egress door or window that could to be pulled in? Where are you going to put the darn thing?
Kinda counter intuitive.
Jettison one in forward flight? Regardless of which side the tail rotor is on stranger still.

It is to enable egress with water pressure opposing. Also allows for a little control of where the window goes, providing a little protection to the floats. Kind of makes sense when you think about it. The ergonomics of the system are not the best, tiny little tab to grab on to remove the beading before pulling the window in.

The video below gives a great demonstration of the windows and some of the ergonomic issues.
https://vimeopro.com/rollingball/wrhs/video/353912555
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Old 1st Oct 2022, 00:51
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Try that in the dark after hitting the water with a lot of force and the aircraft rolling over to one side or the other ....finding that pull tab is not something I would want to bet my life on.
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Old 1st Oct 2022, 01:10
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Originally Posted by SASless
Try that in the dark after hitting the water with a lot of force and the aircraft rolling over to one side or the other ....finding that pull tab is not something I would want to bet my life on.
.

The pull tab is highlighted by a HEELS strip to make it easier to locate if underwater/inverted.
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Old 1st Oct 2022, 08:03
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Just noticed we have a Like button now
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Old 1st Oct 2022, 19:15
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One guy I flew with attached a lanyard to the window pull strip loop when he flew as cojo, not sure what that said about his confidence in his captain 😂😂😂
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Old 1st Oct 2022, 20:15
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Having experienced the difficulties of opening a helicopter cockpit door underwater (thankfully in a training scenario) I’d say that anything that helps make it less difficult is a good idea. The door doesn’t open in the expected sense, it gradually “oozes” away from the frame and only with sustained pressure, rather than a push.
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Old 1st Oct 2022, 21:02
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Griffo,

What did you use to craft the Lanyard?
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Old 1st Oct 2022, 21:08
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Perhaps both EEC's reverted to manual and the high side/s were a result of the pilot lowering collective without manually reducing engine power?
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Old 1st Oct 2022, 22:02
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If the pilot did lower the collective.....why would the crew report there was no collective control response felt or observed.....to the point they were convinced there had been a loss of collective control?

Not challenging your suggestion....just trying to correlate what has been reported to what you suggest may have happened.

Certainly if both engines were at max power.....lowering the collective would not have assisted in controlling the Rotor RPM but you would think they would have known whether the aircraft was responding to a collective movement by observing a pitch change in the blades or felt a reaction.
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Old 2nd Oct 2022, 00:41
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My familiarity with PT6’s ended awhile ago, but is it a given that their FADECs have built in history recorders?
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Old 2nd Oct 2022, 01:29
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So far we haven’t heard from the crew, company, manufacturer or the FAA.
Just the usual Rumours, Innuendo and Hearsay.
It will be interesting to see the initial and then final reports. Hopefully CVR / FDR info will be available.
One thing also is that wirh the electrical fire / problems they may have had just blank screens to look at. That would have made figuring out what the heck is happening difficult to say the least.
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Old 2nd Oct 2022, 02:59
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is it a given that their FADECs have built in history recorders
They do John, from an incident report.
Crew Alert System

The primary flight display (PFD) and the multi-function flight display (MFD) present instrumentation to the pilot. The PFD displays FD modes selected, and their status. The MFD displays engine and aircraft system data and the crew alert system (CAS). The CAS displays messages pertaining to the operation and condition of the aircraft to the crew for information and action.

The CAS messages appear in order of priority. Red warnings appear at the top of the list, next are yellow caution messages, third are green advisory messages, and fourth are white status messages. The final line in the list is white text stating ‘END.’ Each page shows twelve lines and crew can scroll through pages. When scrolling, red warnings cannot be hidden and remain at the top of the list on each page.

A warning or caution message will show with a coloured background until acknowledged. Once acknowledged, it appears as coloured text on a black background. Some messages such as “XMSN OVTQ” (main transmission overtorque) will disappear when the condition causing them has passed. White status messages will only show on the ground with weight on wheels.

The “MAINTENANCE” message is significant because following exceedance of a limit such as torque, it will illuminate after landing. The presence of the “MAINTENANCE” message is a cue to an aircraft maintenance engineer (engineer) to investigate and rectify the cause of the message before cancelling the message.
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Old 2nd Oct 2022, 05:57
  #57 (permalink)  
 
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SASless,
I believe it was a double ended dog lead attached to his flight suit 🤷
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Old 2nd Oct 2022, 06:16
  #58 (permalink)  
 
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Pulling the strap makes it only easier to jettison a window. Enough force applied, they jettison with the cord still in place.
Depending on the age, wear etc "enough" might be surprisingly little.
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Old 2nd Oct 2022, 10:03
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Originally Posted by SASless
If the pilot did lower the collective.....why would the crew report there was no collective control response felt or observed.....to the point they were convinced there had been a loss of collective control?

Not challenging your suggestion....just trying to correlate what has been reported to what you suggest may have happened.

Certainly if both engines were at max power.....lowering the collective would not have assisted in controlling the Rotor RPM but you would think they would have known whether the aircraft was responding to a collective movement by observing a pitch change in the blades or felt a reaction.
Surely they must have been able to reduce pitch or they would almost certainly be dead from killing the engines at 200 feet. And if cycling the engine mode switches between idle and flight had an effect (as reported) then I guess the engines must have still been in auto and not manual fuel control. Which debunks my high side theory.
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Old 2nd Oct 2022, 12:31
  #60 (permalink)  
 
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As recently as November 21, 2021 the FAA issued an AD re chafing of wire bundles in the overhead panel of certain AW-139's that required detailed inspections and related corrective actions to include replacing certain Circuit Breakers.

I found the Congressional Record entry that displayed the FAA's AD.

Phrases like "could cause the loss of control of the aircraft" was part of the verbiage.


https://flightaware.com/live/flight/...0220924/2224ZZ

Last edited by SASless; 2nd Oct 2022 at 13:24.
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