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Maintenance Lapse Identified as Initial Problem Leading to Lion Air Crash

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Maintenance Lapse Identified as Initial Problem Leading to Lion Air Crash

Old 3rd Jan 2019, 05:59
  #81 (permalink)  
 
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Unless I missed it, I have been wondering why the Lion Air Engineers did not consult the ( Jakarta based ) BOEING Tech Rep(s) when they were trouble shooting the problem following the flight from DPS to CGK ?
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Old 3rd Jan 2019, 07:14
  #82 (permalink)  
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And we probably will never know for sure what happened as CNN this morning reported that the search for the CVR and more debris have been abandoned
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Old 3rd Jan 2019, 14:59
  #83 (permalink)  
 
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Originally Posted by CONSO View Post
RE FCeng84 # 63
Interesting - a pic of " typical " AOA Sensor shows 8 holes in post # 58
...
That is not a "typical" AOA Sensor. This pic shows the sensor of an B737MAX Sensor!
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Old 3rd Jan 2019, 15:37
  #84 (permalink)  
 
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Originally Posted by IFixPlanes View Post
That is not a "typical" AOA Sensor. This pic shows the sensor of an B737MAX Sensor!
Are you implying that it's different from the sensor on the NG ?
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Old 3rd Jan 2019, 15:43
  #85 (permalink)  
 
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No, PN 0861FL1 can be installed on NG and MAX.
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Old 3rd Jan 2019, 16:49
  #86 (permalink)  
 
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Originally Posted by IFixPlanes View Post
No, PN 0861FL1 can be installed on NG and MAX.
Thanks, that helps to discount the theory that the wrong part number was fitted to the accident aircraft and had to be forced to fit.
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Old 3rd Jan 2019, 17:25
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Originally Posted by ATC Watcher View Post
And we probably will never know for sure what happened as CNN this morning reported that the search for the CVR and more debris have been abandoned


IF that is confirmed as a final decision, then I find it unbelievable.

Last edited by phil gollin; 3rd Jan 2019 at 17:26. Reason: typo
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Old 3rd Jan 2019, 17:41
  #88 (permalink)  
 
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Originally Posted by phil gollin View Post

IF that is confirmed as a final decision, then I find it unbelievable.
No, Lion is stopping their search. The Indonesian government is going to step in and resume searching, albeit with arguably less capable equipment.

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Old 3rd Jan 2019, 17:53
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Originally Posted by phil gollin View Post

IF that is confirmed as a final decision, then I find it unbelievable.
Any money more spent on this search would probably be much better spent in extra sim time for the pilots.
Don't think the CVR will tell you why the AoA sensor was reading wrong.

An improvement for MCAS is already under way at Boeing as far as i understood. Anyway any improvement in that area can be made without finding any further parts.

What do you think further search will provide?
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Old 3rd Jan 2019, 18:10
  #90 (permalink)  
 
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Originally Posted by wiedehopf View Post
Don't think the CVR will tell you why the AoA sensor was reading wrong.
No, of course it won't.

But the CVR will, in all likelihood, help the investigators (and us) to understand what happened differently on the accident flight compared to the previous flights where the same problems were mitigated by the crews' actions.

Personally, I think we stand to learn a lot from that.
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Old 3rd Jan 2019, 23:21
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No, PN 0861FL1 can be installed on NG and MAX.
This is correct. UT manufactures only 2 models of the sensor, one wing mounted, Model 0012, and the fuselage mounted Model 0861...
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Old 3rd Jan 2019, 23:43
  #92 (permalink)  
 
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Question

Originally Posted by underfire View Post
This is correct. UT manufactures only 2 models of the sensor, one wing mounted, Model 0012, and the fuselage mounted Model 0861...
Since the sensor shown seems to be for the left side,is there a different dash number for the right side or is the change taken care of by mounting ' upside down ' on right side and acomodated via electrical ?
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Old 4th Jan 2019, 08:53
  #93 (permalink)  
 
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Originally Posted by CONSO View Post
Since the sensor shown seems to be for the left side,is there a different dash number for the right side or is the change taken care of by mounting ' upside down ' on right side and acomodated via electrical ?
Given that, as posted earlier, the physical movement limits of the AoA vane are the same in both directions, there is no need for the sensor to be handed. The aircraft is clever enough to understand that clockwise rotation of one vane means the same as anticlockwise rotation of the one on the other side.

The other giveaway is that the Part Description on vendors' and MRO websites doesn't include a "LH" or "RH" qualifier:

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Old 4th Jan 2019, 09:43
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Originally Posted by tarkay01 View Post
The Indonesian government is going to step in and resume searching, albeit with arguably less capable equipment.
Less capable equipment? That'd be difficult. The MPV Everest was only fitted with a pair of Triton XLX ROVs and a Forum Comanche ROV. None of those ROVs are particularly useful for search work unless you intend to search visually for a target sitting on the surface of the sea floor. On the basis that the CVR is almost certainly buried in mud the whole Everest exercise was essentially a waste of time and money. What's required is an acoustic sub-bottom profiler.
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Old 4th Jan 2019, 12:02
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given the 'keyed' bolt pattern, the unit can be either RH or LH
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Old 4th Jan 2019, 14:38
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Originally Posted by underfire View Post
given the 'keyed' bolt pattern, the unit can be either RH or LH
Correct, though the photo isn't the variant that's fitted to the 737NG/Max.

See my previous post, and this is what it looks like in situ, courtesy of Burkhard Domke:



There are no fewer than four locating pegs, plus what look like non-uniformly-spaced mounting bolts, designed to Murphy-proof the sensor against being fitted out-of-alignment, but which allow it to serve as the LH or RH sensor.
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Old 4th Jan 2019, 14:45
  #97 (permalink)  
 
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Originally Posted by DaveReidUK View Post
Given that, as posted earlier, the physical movement limits of the AoA vane are the same in both directions, there is no need for the sensor to be handed. The aircraft is clever enough to understand that clockwise rotation of one vane means the same as anticlockwise rotation of the one on the other side.

The other giveaway is that the Part Description on vendors' and MRO websites doesn't include a "LH" or "RH" qualifier:


translation- must be an electrical function built in somewhere in software or wiring ? or having a connector pin open/blocked differently on each side. ....
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Old 4th Jan 2019, 15:31
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Correct, though the photo isn't the variant that's fitted to the 737NG/Max.
The AOA sensor you showed is from Rosemont. The AOA sensor on the MAX is supplied by United Technologies.

This looks like its installed on a battleship, not a max!

EDIT: Even though the UT AoA sensor is advertised as mounted on the LionAir MAX, either there are multiple options, or multiple manufacturers...

Spirit of Renton MAX is the rosewood you mentioned Dave


Last edited by underfire; 4th Jan 2019 at 15:51.
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Old 4th Jan 2019, 15:45
  #99 (permalink)  
 
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Originally Posted by underfire View Post
The AOA sensor you showed is from Rosemont. The AOA sensor on the MAX is supplied by United Technologies.
Rosemount Aerospace Inc is a division of what was United Technologies, now Collins Aerospace.

Air Data Systems - Collins Aerospace
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Old 4th Jan 2019, 15:46
  #100 (permalink)  
 
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Here is the "keyed" bolt pattern of the 737MAX AOA:

You can see that is is symmetrical and due to the fact that the alignment bushings are at 0 and 180 it can be installed on both side simply by a 180 turn.
@ underfire:
The MAX also use the PN 0861FL1 (Rosemont) - check the IPC (if you can...)
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