Go Back  PPRuNe Forums > Aircrew Forums > Rotorheads
Reload this Page >

AW139 incident - Houma

Rotorheads A haven for helicopter professionals to discuss the things that affect them

AW139 incident - Houma

Old 26th Sep 2022, 09:26
  #1 (permalink)  
Thread Starter
 
Join Date: Oct 1999
Location: Den Haag
Age: 57
Posts: 6,218
Received 317 Likes on 176 Posts
AW139 incident - Houma

Some conflicting information, but certainly seems to have been a challenging situation to deal with, that had a good outcome: https://aviation-safety.net/wikibase/283731
212man is offline  

Top Answer

1st Oct 2022, 08:03
[email protected]
 
Join Date: Apr 2000
Location: EGDC
Posts: 10,289
Received 608 Likes on 266 Posts
Just noticed we have a Like button now
Old 26th Sep 2022, 10:13
  #2 (permalink)  
 
Join Date: Apr 2000
Location: EGDC
Posts: 10,289
Received 608 Likes on 266 Posts
Originally Posted by 212man
Some conflicting information, but certainly seems to have been a challenging situation to deal with, that had a good outcome: https://aviation-safety.net/wikibase/283731
Wow, stuff even the sim instructors hadn't thought of!

Great effort to walk away from it with everyone safe
crab@SAAvn.co.uk is offline  
Old 26th Sep 2022, 12:18
  #3 (permalink)  
 
Join Date: May 2002
Location: Downeast
Age: 75
Posts: 18,267
Received 467 Likes on 191 Posts
Excellent Airmanship....and I bet you the Checklist did not have pages enough for the problems encountered.

This is a story I would live to listen to being told by the Crew.

Very well done!

Now for the investigation to determine not only what happened....but why....to ensure another crew does not ever have to deal with such a problem again.
SASless is offline  
The following users liked this post:
Old 26th Sep 2022, 14:19
  #4 (permalink)  
Thread Starter
 
Join Date: Oct 1999
Location: Den Haag
Age: 57
Posts: 6,218
Received 317 Likes on 176 Posts
Certainly sounds like something you don't want to happen at night 100nm from land, or in IMC above mountains!
212man is offline  
Old 26th Sep 2022, 16:26
  #5 (permalink)  
 
Join Date: May 2002
Location: Downeast
Age: 75
Posts: 18,267
Received 467 Likes on 191 Posts
Errrr......ahhhh......call me a Scaredy Cat but I would not want to have that happen to me while setting on the Ramp.

Boredom is good!
SASless is offline  
Old 26th Sep 2022, 16:43
  #6 (permalink)  
 
Join Date: Mar 2007
Location: Hobe Sound, Florida
Posts: 949
Received 32 Likes on 26 Posts
Concur with comments above. Does it sound like the crew was facing a multiple basic instrument failure that was beyond the 10 to the minus 9 probability?
Edited: Oh, and combined with similarly improbable engine control issue?

Last edited by JohnDixson; 26th Sep 2022 at 16:45. Reason: Additional thought
JohnDixson is offline  
Old 26th Sep 2022, 18:06
  #7 (permalink)  
 
Join Date: Sep 2003
Location: Redding CA, or on a fire somewhere
Posts: 1,956
Received 50 Likes on 15 Posts
Video of it here:

zzzzhttps://www.facebook.com/562437460/videos/pcb.6344994705517913/1534647653658303

Will not let me post link---remove the four "z" at begining
Gordy is offline  
Old 26th Sep 2022, 18:37
  #8 (permalink)  
Thread Starter
 
Join Date: Oct 1999
Location: Den Haag
Age: 57
Posts: 6,218
Received 317 Likes on 176 Posts
Originally Posted by Gordy
Video of it here:

zzzzhttps://www.facebook.com/562437460/videos/pcb.6344994705517913/1534647653658303

Will not let me post link---remove the four "z" at begining
Been removed now it seems
212man is offline  
Old 26th Sep 2022, 19:19
  #9 (permalink)  
 
Join Date: May 2002
Location: Downeast
Age: 75
Posts: 18,267
Received 467 Likes on 191 Posts
Some photos at the Houma Fire Department Facebook Page.....

https://www.facebook.com/houmafire

SASless is offline  
Old 26th Sep 2022, 23:33
  #10 (permalink)  
 
Join Date: Jan 2019
Location: Michigan
Posts: 22
Received 1 Like on 1 Post
Congratulations to the crew for a job well done! A great demonstration of the adage: “never stop flying the aircraft”! I only hope that I could do as well!
Fun_police is offline  
Old 27th Sep 2022, 03:18
  #11 (permalink)  
 
Join Date: Feb 2004
Location: longwayplace
Posts: 238
Likes: 0
Received 3 Likes on 2 Posts
Video
Bomber ARIS is offline  
Old 27th Sep 2022, 08:20
  #12 (permalink)  
 
Join Date: Apr 2000
Location: EGDC
Posts: 10,289
Received 608 Likes on 266 Posts
The ASN report says they chopped the engines at 200' but that looked like a powered approach all the way to the ground - with judicious use of the Engine Mode .switches.

Bloody good job all round, probably make an excellent CRM lecture.
crab@SAAvn.co.uk is offline  
Old 27th Sep 2022, 09:14
  #13 (permalink)  
 
Join Date: Jul 2002
Location: UK
Posts: 2,953
Received 12 Likes on 8 Posts
Originally Posted by Bomber ARIS
Considering the situation, what a greaser! Chapeau to the crew.
Bravo73 is offline  
Old 27th Sep 2022, 10:54
  #14 (permalink)  
 
Join Date: Dec 2001
Location: GA, USA
Posts: 3,182
Likes: 0
Received 11 Likes on 8 Posts
I dare say this is what you call the Right Stuff.
B2N2 is offline  
Old 27th Sep 2022, 12:56
  #15 (permalink)  
 
Join Date: May 2002
Location: Downeast
Age: 75
Posts: 18,267
Received 467 Likes on 191 Posts
The question I am looking for will be what caused he Flight Control issues that were reported.

Some 139 pilots might weigh in on that.

One discussion of the AW-139 I have read stated the Aircraft had mechanical linkages combined with an AFCS that had equal authority to that of the Pilot.

So am I right to think with the Essential buses gone awry due to an electrical fire....would that somehow cause a problem where the Pilots could lose "control" of he aircraft due to the AFCS being left in a mode that could not be removed by the Pilots using normal means to do so?

Or....would the Pilots have to over power the AFCS and Force Trim by manual use of the flight controls?

Just some guessing at probable causes based upon what media reports are out at this time thus remaining in the "asking' and "guessing" mode of query.

Assuming the AFCS and FMS had been set to track "NAV" or "HDG" and maintain 6,000 Feet....and you could not get the AFCS to respond to any other commands....what would the control forces that would be felt by the Pilots?

I also assume the Essential Buses power their associate Emergency buses which means if all four buses are failed....there is not much left to work with in coping with the problems.

How are the Engine Control switches. powered.....which bus are they fed by?

For sure this shall be a very interesting Investigation to figure out what happened, why, what issues the Pilots had to deal with, and how they managed to do so in such am excellent manner.

SASless is offline  
Old 27th Sep 2022, 13:11
  #16 (permalink)  
Thread Starter
 
Join Date: Oct 1999
Location: Den Haag
Age: 57
Posts: 6,218
Received 317 Likes on 176 Posts
the Aircraft had mechanical linkages combined with an AFCS that had equal authority to that of the Pilot.
I'm not a 139 pilot, but this doesn't sound any different to most AFCS systems, especially with upper modes. SAS has fast acting low authority (5-10%) actuators, ATT has slow moving, high authority (100%) actuators. Neither has the power to not be overcome by pilot input, even if the FTR or trim release do not function.
212man is offline  
Old 27th Sep 2022, 14:02
  #17 (permalink)  
 
Join Date: May 2002
Location: Downeast
Age: 75
Posts: 18,267
Received 467 Likes on 191 Posts
What amount of physical force would be required to overpower the AFCS actuators and the Force Trim Gradient.....assuming that is what you had to do?

If both DC Essential buses failed....would that also take out. the DC Emergency buses?

What capabilities would be lost re systems control...AFCS, Stick Trim, Force Trim Release, flight instruments, Engine control....etc?

Looking for 139 specific answers.


SASless is offline  
Old 27th Sep 2022, 14:57
  #18 (permalink)  
 
Join Date: Sep 2005
Location: Montreal
Posts: 714
Received 13 Likes on 10 Posts
Looks powered at the end, then engines to idle, high flare pulling all the rpm off and a somewhat high ROD to runway impact that cleaned the gear off. Speed looked good for a full-on auto. Can't be too critical of the touchdown without knowing what was going on inside - what engine/flight instrumentation was still working, were the pilots fighting any AFCS or autopilots.

Ah yes, the mysteries of the AW139 electrical system, makes you wish you paid more attention in class. This might lead to a 76-style bus recovery mod.
malabo is offline  
Old 27th Sep 2022, 17:05
  #19 (permalink)  
 
Join Date: Apr 2000
Location: EGDC
Posts: 10,289
Received 608 Likes on 266 Posts
The rate of descent is way too low for a full down auto from any height in a 139 - it looks like they waited until they were very low to chop the second engine, I suspect the first was chopped just before the big flare.
crab@SAAvn.co.uk is offline  
Old 27th Sep 2022, 17:15
  #20 (permalink)  
 
Join Date: Apr 2000
Location: EGDC
Posts: 10,289
Received 608 Likes on 266 Posts
When the EECs fail the engines should revert to manual control but beeping the ECLs would need electrical power - ISTR they can be moved manually but can't remember if the link from ECL to FCU is mechanical or electrical.

I presume if they had to use the Eng Mode switches, and they worked, that there was some electrical power somewhere.
crab@SAAvn.co.uk is offline  

Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.