Ethiopian B788 depressurization en-route to Dublin

Jack1985

Alarming reports to read concerning ET502 which was en-route to DUB. I am shocked with the actions of the crew here;

An Ethiopian Airlines Boeing 787-8, registration ET-AOP performing flight ET-502 (sch.dep. Mar 4th) from Addis Ababa (Ethiopia) to Dublin (Ireland), was enroute at FL400 over the Red Sea about 60nm southwest of Jeddah (Saudi Arabia) when the crew selected the emergency squawk into the transponder and descended the aircraft to FL100 being level at FL100 9 minutes after leaving FL400 (average sinkrate 3333 fpm). The aircraft turned around to return to Addis Ababa. About 10 minutes after levelling off at FL100 the aircraft climbed back to FL240 maintaining FL240 until reaching the top of descent into Addis Ababa. The aircraft landed safely back in Addis Ababa about 2:20 hours after leaving FL400.

The airline apologized to their passengers for the "minor technical problem", a replacement aircraft would take them to Dublin.

A replacement Boeing 787-8 registration ET-AOQ reached Dublin with a delay of 6:15 hours.

The occurrence aircraft returned to service 21 hours after landing back.

On Mar 10th 2019 The Aviation Herald received information that the aircraft was enroute at FL400 with no cockpit indication, however, the passenger oxygen masks were released and most of the passenger service units were activated. The crew initiated an emergency descent. Once level at FL100 the crew assessed the situation, however, no reason was apparent of why the oxygen masks had been released. The crew therefore decided to climb to FL240 and return to Addis Ababa. No second depressurization occurred on the way back. Maintenance subsequently found the forward cargo door seal was damaged, the high difference of cabin pressre to ambient pressure (at FL400) caused the cargo door to shift slightly out of position releasing the cabin air causing a loss of cabin pressure. The seal subsequently closed again at FL100. All passenger service units were replaced, the seal was replaced. An investigation has been initiated into why the crew climbed back to FL240 returning to Addis Ababa and did not divert to avoid high terrain (MSA around Addis Ababa 14,500 feet, highest mountain peak 3200 meters/10500 feet MSL) on the way back.

Source: http://avherald.com/h?article=4c50ff6c&opt=0

In addition to the events of ET302, serious questions need to be asked here of Ethiopian. The most alarming aspect of the above incident is that ET502 flew back to ADD at FL240 with some cabin oxygen units depleted and it looks like local MSA’s weren’t evaluated should a loss of pressure reoccur ?

basill

Lets wait for the report. Optics don't appear good I would concede but to play devils advocate what if for example they had a small load and were able to reseat the remaining passengers under an O2 unit that hadn't been activated? Would just need to restow the flap back in the closed position and should be good to go once you are assured that the aircraft is pressurising as normal. Then climb back up above MSA and head for home to get repaired and put punters onto another aircraft thereby minimising the disruption for all concerned. In relation to the MSA I haven't flown in that area but again giving the crew crew credit perhaps they had company escape routes which could assure them of getting from FL240 to FL100 should the need arise? Its a bit misleading to state the MSA around Addis without determining if there are escape routes. If we took that analogy then nobody would fly across the Alps, Himalayas etc. Finally its a modern ETOPS airliner so will no doubt will have sat comm and I am sure the crew were in contact with operations/maintenance back in base and discussed their proposed course of action. Will see what the report states.

smurfjed

Divert to the left into Sudan, right into Saudi, not great options.

Jack1985

basill wrote: »

Lets wait for the report. Optics don't appear good I would concede but to play devils advocate what if for example they had a small load and were able to reseat the remaining passengers under an O2 unit that hadn't been activated? Would just need to restow the flap back in the closed position and should be good to go once you are assured that the aircraft is pressurising as normal. Then climb back up above MSA and head for home to get repaired and put punters onto another aircraft thereby minimising the disruption for all concerned. In relation to the MSA I haven't flown in that area but again giving the crew crew credit perhaps they had company escape routes which could assure them of getting from FL240 to FL100 should the need arise? Its a bit misleading to state the MSA around Addis without determining if there are escape routes. If we took that analogy then nobody would fly across the Alps, Himalayas etc. Finally its a modern ETOPS airliner so will no doubt will have sat comm and I am sure the crew were in contact with operations/maintenance back in base and discussed their proposed course of action. Will see what the report states.

Just to point out the flight appears to have operated nearly full with video posted online of the emergency descent depicting a full cabin section. Ethiopian also replaced the oxygen in all PSU's. I'm not going to get into discussing alternative diversion options, but Egyptian airspace was ahead and left, I understand absolutely how a return to base facilitates is the best option however taking a step back and looking at the events and actions taken, this is not good.

EchoIndia

The fact of it being en route to Dublin is of no particular relevance. The Dublin stop is a technical one only; ET502 is an ADD-YYZ service with no Dublin traffic carried.

smurfjed

I'm not going to get into discussing alternative diversion options, but Egyptian airspace was ahead and left,

OK what would you do in the situation? Also have you looked at the Grid MORA's surrounding Addis?

NIMAN

This is the same plane that crashed?

TheMilkyPirate

NIMAN wrote: »

This is the same plane that crashed?

No.

smurfjed

This was a Boeing 787-8 the crashed aircraft was a 737-8 Max