Another Southwest close call
Flaps Extended = no MCAS.
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Vessbot. So what happens when go around is selected and the Flaps have been left out 15 degrees. With power coming up, and the FO feels the Nose get light, could he have pushed too hard?
Thinking over rotation, could MCAS deploy? His saturation level as high as it was, could he have Retracted Flaps then gotten as alarmed with Pitch Rate down and then pulled back? With unexpected MCAS deployment, well, talk about saturation. Seeing the FO's mess, was Captain as unsure of the flight path as PF?
Thinking over rotation, could MCAS deploy? His saturation level as high as it was, could he have Retracted Flaps then gotten as alarmed with Pitch Rate down and then pulled back? With unexpected MCAS deployment, well, talk about saturation. Seeing the FO's mess, was Captain as unsure of the flight path as PF?
Then in addition what the pilot did, there's the question of what were the avionics doing, and could they have added to the process.
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The aircraft levelled off and had a thrust setting that maintained speed. Why would manually advancing the throttles come with an airpeed loss? There was no climb.
Do we expect that there will ever be a public report? All I have heard is that FAA is investigating. I have not heard of any reason for NTSB to become involved.
Do we expect that there will ever be a public report? All I have heard is that FAA is investigating. I have not heard of any reason for NTSB to become involved.
Perhaps someone who believes the leaked "report" provides an accurate account would be kind enough to break out each significant reported event and assign a time tag to it. We would then be able to reconcile the account with the previously posted ADS-B data plots.
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Somatogravic Illusions
I still have a belief based on the actions initiated AFTER TOGA. Rapid acceleration, Somatogravic illusion effect, without interpreting the accurate flight instrument display the result would be push down and an added twist, pull the throttles back.
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Fully agree Colgan crash had this (Pilot Union input to NTSB -- in NTSB Docket). Somatogravic is a real killer that cannot be fully duplicated in a simulator ( whreas somatogyric can be)
Colgan
Colgan and Somatographic? As I recall Captain was flying and when he heard the STALLSTALL he Pulled, FO had retracted flap. (sic). The warning was spurious, as they hadn't lowered the bug after switching off anti ice. Aircraft did not spin until after it actually Stalled... He pulled all the way down.
Some very experienced instructors will tell you that once in a blue moon they get someone who is wired to interpret significantly less than 1g as stalling, so push forward, which reduces the g, which leads to more pushing forward, etc. I once witnessed an aircraft enter a progressively steepening dive from level flight, straight into the ground on finals killing the pilot: no medical conditions, no aircraft anomalies, nothing. I don’t know if there’s any literature on the subject but it’s talked about in the gliding world, where low g is experienced at quite an early stage of training, in order to prepare instructors to take over should the pupil end up bunting uncontrollably. Still extremely rare, though, and could easily end up in the LoC/mishandling statistics.
I think low g familiarization was a standard part of the BGA (British Gliding Association) training syllabus. I certainly experienced it in UK and demonstrated to students there. The nearest to that in USA was simulated winch launch cable breaks. I doubt any US SEL, MEL, ATP pilots ever experience low g during training.
Last edited by EXDAC; 1st Jul 2024 at 23:07.
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"Submission of the Air Line Pilots Association, International to the National Transportation Safety Board Regarding the Accident Involving Colgan 3407 DHC-8-Q400 DCA09MA027 Clarence Center, NY February 12, 2009" Interesting read. page 44 commences a discussion on the somatogravic illusion.
"FDR data reveals rapid deceleration and that the pilot initially pulled back on the controls, increasing the angle of attack. The CVR is inconclusive, except absence of callouts for stall recovery may be supporting indicators. It is probable that the pilot flying initially did not perceive a stall but rather excessive pitch down due to deceleration resulting from power reduction, gear deployment, propeller drag increase, induced drag from increased angle of attack and parasitic drag from flap deployment. The aircraft decelerated 50 knots in 26 seconds, which would produce a strong deceleration force and vestibular illusion of tumbling forward."
The factors relevant to somatogravic illusion ( my memory) include : lack of external horizon - present, midnight in a snow storm: :fatigue - present (CVR had crew yawning),:higher workload - present (Night IFR approach in icing weather - crew commented that they had not seen icing that heavy before):, accelration/deceleration - present (as per quote above): startle - present ( stick shaker activated unexpectedly- icing logic raises activation speed). The NTSB report also makes reference to a possible crew concern that the tailplane would stall as they accumulated ice. The sudden tumbling forward sesnation may have been interprated as this ( the tailplane did not stall, by the way)
"FDR data reveals rapid deceleration and that the pilot initially pulled back on the controls, increasing the angle of attack. The CVR is inconclusive, except absence of callouts for stall recovery may be supporting indicators. It is probable that the pilot flying initially did not perceive a stall but rather excessive pitch down due to deceleration resulting from power reduction, gear deployment, propeller drag increase, induced drag from increased angle of attack and parasitic drag from flap deployment. The aircraft decelerated 50 knots in 26 seconds, which would produce a strong deceleration force and vestibular illusion of tumbling forward."
The factors relevant to somatogravic illusion ( my memory) include : lack of external horizon - present, midnight in a snow storm: :fatigue - present (CVR had crew yawning),:higher workload - present (Night IFR approach in icing weather - crew commented that they had not seen icing that heavy before):, accelration/deceleration - present (as per quote above): startle - present ( stick shaker activated unexpectedly- icing logic raises activation speed). The NTSB report also makes reference to a possible crew concern that the tailplane would stall as they accumulated ice. The sudden tumbling forward sesnation may have been interprated as this ( the tailplane did not stall, by the way)
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More on the somatorgravic effect and other aspects of spatial disorientation can be found in this very readable paper. NCBI Bookshelf. A service of the National Library of Medicine, National Institutesof Health Physiology Of Spatial Orientation Rachel K. Meeks Jackie Anderson Paul M. Bell Last Update:August 14, 2023
The effect of linear acceleration (or deceleration) on percieved nose-up/nose-down attitude is surprisingly strong. An Australian King-Air (VH-LFH) crashed just off the end of the runway during a night takeoff, and the ATSB report stated "an aircraft accelerating from 100 to 130 knots in 10 seconds generates an acceleration on the pilot of 0.16 G, which is sufficient to produce the sensation of a 9 degree pitch-up"
The effect of linear acceleration (or deceleration) on percieved nose-up/nose-down attitude is surprisingly strong. An Australian King-Air (VH-LFH) crashed just off the end of the runway during a night takeoff, and the ATSB report stated "an aircraft accelerating from 100 to 130 knots in 10 seconds generates an acceleration on the pilot of 0.16 G, which is sufficient to produce the sensation of a 9 degree pitch-up"
Submission of the Air Line Pilots Association, International to the National Transportation Safety Board Regarding the Accident Involving Colgan 3407 DHC-8-Q400 DCA09MA027 Clarence Center, NY February 12, 2009" Interesting read. page 44 commences a discussion on the somatogravic illusion.
"FDR data reveals rapid deceleration and that the pilot initially pulled back on the controls, increasing the angle of attack. The CVR is inconclusive, except absence of callouts for stall recovery may be supporting indicators. It is probable that the pilot flying initially did not perceive a stall but rather excessive pitch down due to deceleration resulting from power reduction, gear deployment, propeller drag increase, induced drag from increased angle of attack and parasitic drag from flap deployment. The aircraft decelerated 50 knots in 26 seconds, which would produce a strong deceleration force and vestibular illusion of tumbling forward."
The factors relevant to somatogravic illusion ( my memory) include : lack of external horizon - present, midnight in a snow storm: :fatigue - present (CVR had crew yawning),:higher workload - present (Night IFR approach in icing weather - crew commented that they had not seen icing that heavy before):, accelration/deceleration - present (as per quote above): startle - present ( stick shaker activated unexpectedly- icing logic raises activation speed). The NTSB report also makes reference to a possible crew concern that the tailplane would stall as they accumulated ice. The sudden tumbling forward sesnation may have been interprated as this ( the tailplane did not stall, by the way)
^^^^^^°°°°°°°^^^^^
THIS STATEMENT NEEDS TO BE FLIPPED:
"""*FDR data reveals rapid deceleration and that the pilot initially pulled back on the controls, """"
..Flaps were out and the aircraft was trimmed for flaps. The first thing FO did at Stall warning was retract flaps. Pitching down and picking up speed, by the time Captain reacted, pulling up and dumping ajrspeed the game was up. At Stall warning,they had fifteen knots of buffer. SW. activated at ON ANTI ICE bugspeed which they had selected OFF, but neglected to move the bug...StallWarn was spurious. The Crew were called out for lack of sterile cockpit, and poor CRM.
The ANTI ICE was turned off because there was no Icing.
Let's be fair
"FDR data reveals rapid deceleration and that the pilot initially pulled back on the controls, increasing the angle of attack. The CVR is inconclusive, except absence of callouts for stall recovery may be supporting indicators. It is probable that the pilot flying initially did not perceive a stall but rather excessive pitch down due to deceleration resulting from power reduction, gear deployment, propeller drag increase, induced drag from increased angle of attack and parasitic drag from flap deployment. The aircraft decelerated 50 knots in 26 seconds, which would produce a strong deceleration force and vestibular illusion of tumbling forward."
The factors relevant to somatogravic illusion ( my memory) include : lack of external horizon - present, midnight in a snow storm: :fatigue - present (CVR had crew yawning),:higher workload - present (Night IFR approach in icing weather - crew commented that they had not seen icing that heavy before):, accelration/deceleration - present (as per quote above): startle - present ( stick shaker activated unexpectedly- icing logic raises activation speed). The NTSB report also makes reference to a possible crew concern that the tailplane would stall as they accumulated ice. The sudden tumbling forward sesnation may have been interprated as this ( the tailplane did not stall, by the way)
^^^^^^°°°°°°°^^^^^
THIS STATEMENT NEEDS TO BE FLIPPED:
"""*FDR data reveals rapid deceleration and that the pilot initially pulled back on the controls, """"
..Flaps were out and the aircraft was trimmed for flaps. The first thing FO did at Stall warning was retract flaps. Pitching down and picking up speed, by the time Captain reacted, pulling up and dumping ajrspeed the game was up. At Stall warning,they had fifteen knots of buffer. SW. activated at ON ANTI ICE bugspeed which they had selected OFF, but neglected to move the bug...StallWarn was spurious. The Crew were called out for lack of sterile cockpit, and poor CRM.
The ANTI ICE was turned off because there was no Icing.
Let's be fair
Last edited by BugBear; 2nd Jul 2024 at 16:06.
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The quotes are directly from the reports as written by persons who were closer to the investigation and far more intelligent than I .
My intent is not to re-do the Colgan investigation. My intent is to highlight an aspect of human physiology that can turn very deadly, very quickly under certain circumstances.
My intent is not to re-do the Colgan investigation. My intent is to highlight an aspect of human physiology that can turn very deadly, very quickly under certain circumstances.
