Posted on 03/12/2019 10:11:53 AM PDT by Moonman62
About 12:38, the controller informed the pilots that they would be past the area of weather in about 18 miles, that they could expect a turn to the north for a base leg to the approach to runway 26L, and that weather was clear west of the precipitation area. The pilots responded, “sounds good” and “ok.” At this time, radar and ADS-B returns indicated the airplane levelled briefly at 6,200 ft and then began a slight climb to 6,300 ft.
Also, about this time, the FDR data indicated that some small vertical accelerations consistent with the airplane entering turbulence. Shortly after, when the airplane’s indicated airspeed was steady about 230 knots, the engines increased to maximum thrust, and the airplane pitch increased to about 4° nose up and then rapidly pitched nose down to about 49° in response to column input. The stall warning (stick shaker) did not activate.
FDR, radar, and ADS-B data indicated that the airplane entered a rapid descent on a heading of 270°, reaching an airspeed of about 430 knots. A security camera video (figure 4) captured the airplane in a steep, generally wings-level attitude until impact with the swamp. FDR data indicated that the airplane gradually pitched up to about 20 degrees nose down during the descent.
Hope the CVR didn’t record Aloha snackbar on the way down.
I imagine there was at least one “What the *&!@ are doing?”
There was a dry line front they flew into ATC reported precipitation. Strong wind direction change with very strong gusts. Most likely damage to control surfaces put that bird in the water. Doubt it was intentional.
If you’ve ever experienced a dry line front with high wind change you would understand.
OMG 11!!1 ITS A SOFTWARE GLITCH THE 737 CRACHING AGAIN ARE THE UN CLIMATE GUYS ALL DEAD !`1?
As FYI — this was a February 23, 2019 crash.
Is there a flightradar24 link for this? I cannot find it because I don’t know what I’m doing over there. GTI3591 does not come up with a hit.
The airspeed was steady and high enough for flight.
So I do understand.
The scenario you are putting forth would have been indicated on the data recorder. According to the NTSB, it wasn’t.
This airplane didn’t have the 737-Max style pitch override, so that feature could not have caused this crash. The autothrottles are very easily overridden but if the autopilot stayed on it is tough to physically override the pitch, roll, and yaw. I can’t imagine neither pilot using the quick disconnect on the yoke for the autopilot, or not overriding the autothrottle, if they knew it was in a dive. And surely with 49 degrrees of pitch they knew.
The fact that the dive was arrested to 20 degrees nose-low seems to suggest either a struggle by one pilot against the strength of the other, or a struggle against the (still-connected) autopilot to pull out of the dive.
In the Egypt Air flight 990 crash (also a 767) the pilots were fighting each other’s control input to the point that the horizontal stabilizer linkage separated, with each side contolling only half of the horizontal stab. That would diminish either pilot’s ability to pull out of a dive (or to steepen the dive) if they were in opposition in their yoke movements. There hasn’t been enough data released from this mishap to know.
And 450 knots? Ridiculously fast in any recovery scenario from that low of an altitude.
Right now I am leaning even more toward the “deliberate act” scenario. Occam’s razor.
The NTSB has now changed the wording, saying the nose down was due to elevator deflection, but not saying what caused it:
About 12:38, the controller informed the pilots that they would be past the area of weather in about 18 miles, that they could expect a turn to the north for a base leg to the approach to runway 26L, and that weather was clear west of the precipitation area. The pilots responded, “sounds good” and “ok.” At this time, radar and ADS-B returns indicated the airplane levelled briefly at 6,200 ft and then began a slight climb to 6,300 ft.
Also, about this time, the FDR data indicated that some small vertical accelerations consistent with the airplane entering turbulence. Shortly after, when the airplane’s indicated airspeed was steady about 230 knots, the engines increased to maximum thrust, and the airplane pitch increased to about 4° nose up. The airplane then pitched nose down over the next 18 seconds to about 49° in response to nose-down elevator deflection. The stall warning (stick shaker) did not activate.
FDR, radar, and ADS-B data indicated that the airplane entered a rapid descent on a heading of 270°, reaching an airspeed of about 430 knots. A security camera video (figure 4) captured the airplane in a steep, generally wings-level attitude until impact with the swamp. FDR data indicated that the airplane gradually pitched up to about 20 degrees nose down during the descent.
Something looks very wrong about this. IAH has a LOT of cargo planes in and out of there.
Any release of cockpit conversation?
Just a general description. The NTSB said the quality was poor. There’s no transcript yet.
“There is more info on this thread:
http://www.freerepublic.com/focus/f-chat/3730070/posts “
I’m not convinced that your picture on entry 24 does not tell the story. An outflow boundary can be quite turbulent in a short horizontal distance and you never want to fly there, particularly if there is a roll cloud visible. The turbulence extends well beyond any visible cloud. I suspect the plane suffered its fatal damage while passing through the outflow boundary.
The picture you provided shows pretty much the south end of a squall line hundreds of miles long, quite similar to that existed during the Washington, Illinois tornado a few years ago.
Revised to:
"The airplane then pitched nose down over the next 18 seconds to about 49° in response to nose-down elevator deflection."
These are completely different, with the second quote removing the crew from implied causation.
They gave away too much information the first time.
According to someone on this thread the data recorder keeps track of force applied to the control column. If true, the NTSB knows what happened. They just don’t want to say anything that seems conclusive at this point, but I think they already slipped with the first release.
https://www.reddit.com/r/flying/comments/b08v9q/ntsb_issues_investigative_update_on_atlas_air_3591/
When I look at the video of the final seconds of flight the plane looks like it’s under control to me.
Firsthand from an ex-Atlas employee (pilot), now working for [I should not mention] who is familiar (I believe type rated) with the 767/757 and also was privy to the investigation:
The mishap crew was descending through about 6,200 feet when ATC asked them to expedite down to 3,000 feet. The first officer was flying, autopilot on. . He selected 3,000 and idle — called for “flaps one” which is an unusual move for a descent, as explained to me. He reached across for the speed brake, over the throttles (instead of under as most do). He inadvertently hit the go-around button. This caused the nose to pitch up as the throttles went to max power. They were in the clouds. The first officer was startled and interpreted the commotion as a stall. He violently pushed the nose over to 2.5 g’s (an absolutely enormous startle factor, and way too much of a push on the yoke for any reason). The airplane was still accelerating, more quickly as the nose went through the horizon, ever more nose-low (and I’m not sure of this detail but I think not pulling back the throttles, thinking he needed the power to get out of a stall). The startle factor of the negative g’s temporarily kept the captain from reacting (and may have injured his head on the overhead panel if he was not strapped in tightly) but he figured out what was happening in the dive and pulled back on his yoke. They were so much in opposition on the controls the yokes split (no longer connected). As they screamed through about 2,000 feet the nose came up some but it was too late. They impacted at high speed and a steep angle.
The first officer had a poor record at Atlas and at least one other airline (check ride failures).
The jumpseater was in the cockpit (cargo configuration). The recovery team knew exactly where the flight data and cockpit voice recorders were but they were buried so deep in the ground and water it took a long time to excavate them. He told me some other gruesome details of the recovery operation I will not mention.
So bottom line: 100 percent preventable pilot error.
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