Ethiopian Airlines, Lebanon, Official Report, Recap, update

Revisiting Ethiopia Flight 409

March 26, 2011 March 26, 2011

We’ve been studying Ethiopia Flight 409 for a while, and now that the official investigation Progress Report is out, we have looked at it with quite some interest. The 28 page report is attached as a pdf at the end of this editorial, so if you haven’t seen it yet, we have it handy–

In some places, we find that the report corroborates some of the the points we made (or discovered in our research.)

According to the report:

“Instruments meteorological conditions prevailed for the flight, and the flight was on an instrument flight plan. The accident occurred at night in dark lighting conditions with reported isolated cumulonimbus clouds and thunderstorms in the area.”

Their report also states:
The Lebanese Civil Aviation Authority reviewed the data from the Lebanese Meteorological Services that was collected on 25 January, 2010 after the accident. Meteorological data revealed some significant meteorological conditions in the area at the time of the accident. Relevant meteorological documents are included in the investigation file and will be analyzed during the investigation.

1.7.1 General meteorological situation
At the time of the accident, there was thunderstorms activity southwest and west of the field, as well as to the northwest on the localizer path for runway 16.

We had found a satellite photo of the area at the time in question and found something more turbulent than isolated cumulonumbus clouds. Here are the details we turned up
(thanks to Prof. Robert H. Holzworth
Departments of Earth and Space Sciences, and Physics
Director, World Wide Lightning Location Network )

WWLLN lightning strokes between (45,35.2) and (33.6, 35.7) coordinates on25 Jan 2010 between 00 and 06 UTC
.
2010/01/25,00:26:01.675091, 33.7925, 35.3157, 18.6, 15 2010/01/25,00:32:36.535404, 33.6762, 35.3223, 2.6, 5 2010/01/25,00:35:33.147928, 33.8152, 35.3989, 17.1, 9 2010/01/25,00:36:46.386409, 33.7880, 35.4182, 6.3, 6 2010/01/25,00:37:57.880969, 33.7473, 35.4083, 12.9, 8 2010/01/25,00:38:56.307703, 33.8144, 35.4480, 6.7, 5 2010/01/25,00:39:52.170965, 33.8098, 35.4486, 22.5, 1 02010/01/25,00:47:07.877656, 33.7658, 35.5138, 16.3, 7 2010/01/25,00:47:08.129640, 33.7532, 35.5187, 6.8, 5 2010/01/25,00:51:28.917459, 33.7313, 35.4897, 15.8, 8 2010/01/25,00:57:16.994854, 33.7712, 35.5668, 6.2, 5 2010/01/25,00:57:17.172976, 33.8877, 35.6009, 3.1, 5 2010/01/25,00:57:16.970924, 33.8230, 35.5664, 9.2, 5 2010/01/25,01:05:02.878083, 33.6379, 35.5348, 10.9, 5 2010/01/25,02:58:51.961652, 33.6073, 35.3703, 2.3, 5 2010/01/25,03:00:31.235850, 33.6450, 35.3881, 5.8, 7 2010/01/25,03:02:45.342786, 33.6157, 35.3553, 4.5, 7 2010/01/25,03:30:07.101084, 33.6511, 35.3185, 17.5, 7 2010/01/25,04:06:25.411422, 33.8432, 35.3648, 10.9, 5 2010/01/25,04:07:31.723296, 33.9087, 35.3844, 7.0, 5 2010/01/25,04:13:12.295902, 33.9543, 35.4151, 17.0, 10 2010/01/25,04:29:17.203911, 33.9865, 35.4613, 20.7, 10 2010/01/25,04:33:22.703869, 33.9637, 35.3229, 7.6, 6 2010/01/25,04:35:07.805894, 33.8709, 35.3297, 13.3, 8 2010/01/25,04:46:45.611497, 33.9634, 35.4145, 12.9, 6 2010/01/25,05:19:51.913652, 33.6442, 35.4520, 19.5, 8 2010/01/25,05:35:10.788571, 33.9139, 35.2087, 9.5, 7 2010/01/25,05:56:25.149281, 33.6332, 35.6535, 14.0, 7

and the satellite photo:

The plane’s on board radar would have normally registered this unacceptable massive super cell in the area where the airplane hit the ocean and the pilot would have adjusted the flight path accordingly. This makes us question if the on board radar was intact and operable. The weather system pictured in the satellite photo is not weather a pilot would voluntarily fly into. So we were not surprised to see this included in the report:

1.17.1.6 Procedure for use of on-board Weather Radar
ET provided its SOP and Boeing procedure for the operation of the weather radar during departure. The procedure will be addressed during the analysis phase.

OTHER POINTS
Our investigation pointed out that when an aircraft fails, it is a crucial part of the research to look at timely Airworthiness Directives (issued before and after) on the type of plane involved and indeed, this has become part of the ongoing research:

1.16.4.1 Removal and Analysis of the Trim Tab section:
ADs were issued (Emergency AD, AD 2010-09-05, AD 2010-17-19) by the FAA respectively on March and August 2010 regarding trim tab control mechanism and this airplane (with serial number 29935) was found affected by these ADs.
Therefore, and in accordance with the Airworthiness Group recommendation, the Investigation Committee decided the removal of the trim tab control mechanism for further test and research.

This is not the final report. The final report is due out this summer. We are looking forward to seeing if it answers some of our questions.

The Official Report