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Ethiopia Reveals Initial Boeing 737 MAX Crash Findings
The Ethiopian Ministry of Transport’s Aircraft Accident Investigation Bureau released its Interim Investigation Report regarding the 2019 Ethiopian Airlines 737 MAX crash. The report goes over the crash and the events leading up to it in excruciating detail. (simpleflying.com) Más...Sort type: [Top] [Newest]
Think for a minute that instead of a possible bird strike disabling the left AOA vane allowing it to give false information, a flock of birds damages both left and right AOA vanes and they both erroneously send info back to the aircraft that is in a stall scenario? However the aircraft attitude, speed, rate of climb are all normal but both stick shakers are firing, the aircraft is trying to trim itself downwards because of known/unknown MCAS...thrust is at climb power! The crew finally turn off the trim cut-out switches while manually trimming but do not reduce power. The aircraft still about 7000’ above ground and now in 100’ fpm descent and almost under control.....the crew decides to turn the cut-out switches back on (probably because they are uncomfortable hand flying) to get the autopilot back and the aircraft dives into the ground at over 5000’ fpm. Bad design for sure, poorly trained crew probably, sign of the times by pushing both aircraft and pilots out the door without adequate testing......definitely. Just an opinion.
Where do you get the idea of the plane being 7000' above the ground? The Addis airport is at nearly 7000' elevation. This explains the continued take-off thrust, the rapid acceleration and the very short duration of the flight.
The aircraft reached 6,200’agl which translates into approx. 13,200’ asl using your stats. The crew had set 14.000 into their altitude alerter.
Flightradar 24 tracker shows highest altitude was about 8500' AMSL. Field elevation is actually 7625'. You can do the math.
875 feet above ground level.
https://www.flightradar24.com/blog/flightradar24-data-regarding-the-crash-of-ethiopian-airlines-flight-302/
NTSB Report - abbreviated
At 5:42:12, the crew requested a vector to return to the airport.
At 5:42:15, the F/O requested “Radar Ethiopian three zero two request vector to return to home » Following ATC instruction to turn to 260°, a new target heading of 262 ° was set.The aircraft heading at that time was 102 degrees.
At 5:42:47, the captain said « Ok, what was it? Master Caution? The F/O says« Master caution? » The captain asked the F/O to verify. The F/O answered “Master Caution Anti Ice”. The captain said “Left Alpha Vane”. The F/O acknowledged“Left Alpha Vane” the FDR data at this time is consistent with the crew pressing the MASTER CAUTION recall button to review the existing faults.
During this phase, the crew was applying an average force of 94 lbs for a long time.
From 5 h 41 min 25 s, bank angle progressively increased to the right and heading increased towards the new selected heading.
At the end of the phase:
- The airplane was at an altitude of 6,200 ft above the airfield elevation (computed from the RH pressure altitude). LH altitude values were 1,250 ft lower.
- Computed airspeed was around 367 kt (RH value), LH erroneous value was 344 kt.
- The pitch angle of the airplane was lower than 1°
- The vertical speed was around + 125 ft/min and decreasing
- The bank angle was around 21° right, with a slight trend to increase.
Phase 5: Stab trim cut out switches back in normal position until the end of the flight (from 5h 43 min 11 s until 5h 43 min 44 s)
At 5:43:11, the crew tried to engage the A/P. A/P warning sounded for 3 s.
At the time of the A/P engagement attempt, 2 short-time manual electrical trim up inputs were recorded , from which it can be concluded that the stabilizer cutout switches had been restored to the normal position6; at this time, the stabilizer position was 2.3 units.
At 05:43:21, approximately five seconds after the last manual electric trim up input, automatic nose-down trim triggered for about 5 s. The stabilizer moved from 2.3 to 1 unit. 3 seconds after the automatic nose-down trim activation, the vertical speed decreased and became negative.
One second before the end of the automatic trim nose-down activation, the average force applied by the crew decreased from 100 lbs to 78 lbs in 3.5 seconds.
In these 3.5 seconds, the pitch angle dropped from 0.5° nose up to -7.8° nose down and the descent rate increased from -100 ft/min to more than -5,000 ft/min.Following the last automatic nose-downtrim activation and despite recorded force of up to 180 lbs, the pitch continued decreasing. The descent rate and the airspeed continued increasing.
At 05:43:36 the EGPWS sounded: “Terrain, Terrain, Pull Up, Pull up”
The recordings stoped 23 seconds after the activation of the 4th automatic nose down trim.
At the end of the recording:
- Computed airspeed values reached 500 kt
- Pitch values were greater than 40° nose down
- Vertical speed values were greater than 33,000 ft/min.
Both recorders stopped recording at around 05 h 43 min 44 s.
At 5:42:12, the crew requested a vector to return to the airport.
At 5:42:15, the F/O requested “Radar Ethiopian three zero two request vector to return to home » Following ATC instruction to turn to 260°, a new target heading of 262 ° was set.The aircraft heading at that time was 102 degrees.
At 5:42:47, the captain said « Ok, what was it? Master Caution? The F/O says« Master caution? » The captain asked the F/O to verify. The F/O answered “Master Caution Anti Ice”. The captain said “Left Alpha Vane”. The F/O acknowledged“Left Alpha Vane” the FDR data at this time is consistent with the crew pressing the MASTER CAUTION recall button to review the existing faults.
During this phase, the crew was applying an average force of 94 lbs for a long time.
From 5 h 41 min 25 s, bank angle progressively increased to the right and heading increased towards the new selected heading.
At the end of the phase:
- The airplane was at an altitude of 6,200 ft above the airfield elevation (computed from the RH pressure altitude). LH altitude values were 1,250 ft lower.
- Computed airspeed was around 367 kt (RH value), LH erroneous value was 344 kt.
- The pitch angle of the airplane was lower than 1°
- The vertical speed was around + 125 ft/min and decreasing
- The bank angle was around 21° right, with a slight trend to increase.
Phase 5: Stab trim cut out switches back in normal position until the end of the flight (from 5h 43 min 11 s until 5h 43 min 44 s)
At 5:43:11, the crew tried to engage the A/P. A/P warning sounded for 3 s.
At the time of the A/P engagement attempt, 2 short-time manual electrical trim up inputs were recorded , from which it can be concluded that the stabilizer cutout switches had been restored to the normal position6; at this time, the stabilizer position was 2.3 units.
At 05:43:21, approximately five seconds after the last manual electric trim up input, automatic nose-down trim triggered for about 5 s. The stabilizer moved from 2.3 to 1 unit. 3 seconds after the automatic nose-down trim activation, the vertical speed decreased and became negative.
One second before the end of the automatic trim nose-down activation, the average force applied by the crew decreased from 100 lbs to 78 lbs in 3.5 seconds.
In these 3.5 seconds, the pitch angle dropped from 0.5° nose up to -7.8° nose down and the descent rate increased from -100 ft/min to more than -5,000 ft/min.Following the last automatic nose-downtrim activation and despite recorded force of up to 180 lbs, the pitch continued decreasing. The descent rate and the airspeed continued increasing.
At 05:43:36 the EGPWS sounded: “Terrain, Terrain, Pull Up, Pull up”
The recordings stoped 23 seconds after the activation of the 4th automatic nose down trim.
At the end of the recording:
- Computed airspeed values reached 500 kt
- Pitch values were greater than 40° nose down
- Vertical speed values were greater than 33,000 ft/min.
Both recorders stopped recording at around 05 h 43 min 44 s.
Not really possible unless measured over some dramatically lower terrain, which doesn't appear. Not even within the rate of climb capabilities of the 737. Also, pressure altitude is not measured AGL but AMSL.
You're trying to argue a blog post from 2019 has more reliable data than a NTSB report?
The series of events with the accident doesn't even make sense if the airplane was at 875' AGL.
The series of events with the accident doesn't even make sense if the airplane was at 875' AGL.
Allan, read this again slowly:
The airplane was at an altitude of 6,200 ft above the airfield elevation (computed from the RH pressure altitude). LH altitude values were 1,250 ft lower.
The airplane was at an altitude of 6,200 ft above the airfield elevation (computed from the RH pressure altitude). LH altitude values were 1,250 ft lower.
What I said was that Flightradar24 flight tracking last reported altitude as about 8500' AMSL. That was at 05:41. I do not believe the plane climbed another 6000' in the remaining two minutes of flight with MCAS pointing the nose at the ground. So yes I think the NTSB report has an error. And, to repeat myself, barometric altimeters do not measure the vertical distance from terrain.