How could these pilots make such a rookie mistake? - CO1943

the dc-9 from Continental Airlines is approaching Runway 2-7 at Houston the landing gear warning horn is sounding loudly inside the cockpit but the pilots are ignoring it the airplane hits the ground violently and comes to a stop at the end of the runway the investigation that followed tried to find out why these experienced Pilots had made such a bizarre mistake foreign Continental Airlines flight 1943 was operated by a DC 9-32 registered November 10556 there were 82 passengers two flight crew members and three flight attendants on board the airplane flight 1943 was a scheduled service between Washington National Airport and Houston Intercontinental Airport the pilot flying was the 37-year-old first officer who had 2200 hours of Total experience Anna passed as United States Air Force pilot flying the F4 Phantom the 50-year-old Captain was the pilot monitoring he had approximately 17 500 hours of experience and he was also a United States Air Force pilot having served in the Vietnam War the weather conditions that day were quite good with 10 miles of visibility and overcast clouds at 2700 feet the plane left Washington at 5 50 p.m Central Standard Time and was cruising at 35 000 feet at 8 40 p.m the ATC cleared Flight 1943 to descent to 13 000 feet while descending the captain read both The Descent and the in-range checklists ten minutes later Houston terminal radar approach cleared the plane to descend to 4000 feet and to join the localizer of Runway 2-7 the crew completed the approach checklist and was then instructed to descend to 2000 feet to join the instrument Landing system of Runway 2-7 the next step for the pilot flying was to start configuring the plane for landing so he asked for the slats to be extended at five the captain moved the slap flap lever to five and confirmed slats are going to five the first officer then requested flaps 15 but after the movement of the control lever looking at the flap gauge he realized that the flaps were not extended he pointed this out to the captain who exclaimed I think the flaps are a few seconds later the landing gear warning horn sounded and so the captain lowered the landing gear lever thereafter the first officer called for the landing checklist and the flaps to be extended to 25. Meanwhile the landing gear warning horn sounded again distracting the captain from executing the landing checklist during the next 12 seconds the first officer called for the flaps to be extended to 40 and then to 50. after that he stated I don't have any flaps without the drag provided by the landing gear and flaps the plane did not slow down while descending on the Glide path and reached an alarmingly high speed of 216 knots a normal approach speed for a dc-9 with Landing flaps is something between 125 and 135 knots at 500 feet above field the worried first officer asked want to take it around but the captain replied no that's all right keep your speed up as the plane got closer to the runway the ground proximity warning system or gpws shouted three times followed by The Continuous sound of the landing gear warning horn at about 160 feet above field with a speed of 206 knots the first officer felt very uncomfortable and questioned the captain wants a landed the captain replied yeah and took control of the airplane a few seconds later the airplane touched down hard with the wheels up at 193 knots indicated AirSpeed as the airplane slid down the runway two controllers on duty in the tower and two airport groundskeepers observed smoke and Fire coming from beneath the airplane the captain was able to maintain directional control with the rudder and the plane stopped in the Grass at the Left End of Runway 2-7 with the dc-9 resting on the ground the pilots shut down the engines in preparation for an emergency evacuation the senior flight attendant informed them that there was smoke in the cabin after the engines stopped the three flight attendants led the passenger evacuation through the inflatable slides in less than one minute all passengers and crew were out of the stranded plane following the accident 12 of the 82 passengers were treated for minor injuries while the five crew members were unharmed the airplane received substantial damage to its lower fuselage estimated repair costs exceeded the airplane's insured value of 2.56 million dollars and it was scrapped the accident was investigated by the national Transportation safety board or NTSB which released the final report one year after the event since both the flaps and the landing gear are hydraulically operated the NTSB suspected that a failure of the hydraulic system could have caused the malfunction hydraulic power on the dc-9 is provided by two independ and hydraulic systems each system is normally pressurized by its respective engine driven hydraulic pump an auxiliary electrically operated pump and an alternate motor pump provide backup pressure sources the output pressure of each engine driven hydraulic pump is controlled by a three position switch in the high position pump output pressure is 3000 psi while the low position reduces the pressure to 1500 PSI the off position depressurizes the system switch is controlling the auxiliary and Alternate hydraulic pumps are also located on the same instrument panel ground takeoff and Landing operations are conducted with the engine driven hydraulic pumps which is in the high position and the auxiliary and Alternate switches on during in-flight operation system pressures are reduced to 1500 PSI by positioning the engine driven pump switches to low and turning the auxiliary and Alternate switches off Continental Airlines procedures require changeover to the low pressure configuration during the completion of the after takeoff checklist the high pressure configuration is enabled before landing during the completion of the in-range checklist by analyzing the cockpit of the crash dc-9 the investigators made an astonishing Discovery the landing gear handle was in the down position and the flap handle was set to 50 but the engine driven hydraulic pump switches were in the low position and the auxiliary and Alternate switches were in the off position this meant that the hydraulic system was operating at low pressure during approach and Landing rendering impossible the extension of flaps and landing gear as the NTSB ascertained that the accident was not caused by a mechanical failure it started to analyze the behavior of the flight crew to understand why they failed to set up the hydraulic system and why they ignored all the indications that warned them of the wrong configure Nation from the cockpit voice recorder they found that the captain omitted one item from the in-range checklist the omitted item hydraulics on and high checked would have enabled the high pressure configuration of the hydraulic system thereby providing pressure to operate the flaps and landing gear the safety board found no evidence indicating that the captain was interrupted or distracted during the performance of the in-range checklist or that the omitted checklist item was obscured the NTSB was unable to determine the specific reason for the captain's omission of the Hydraulics item on the in-range checklist but why didn't they respond properly to the flap extension failure immediately before the first officer requested slats and five degrees of flaps the captain commented shoot I can't play tennis when it's like this well maybe this afternoon it'll clear up actually I've still got a lot of time after moving the flap handle the captain stated slats are going to 5 paused for about 10 seconds and then continued to discuss with the first officer for about 30 seconds the weather as it would affect his afternoon tennis the topic of the captain's conversation indicates that his attention was directed outside the cockpit as he assessed the weather's effect on his tennis plans it would have been unlikely for him to detect the momentary illumination of the master caution light especially if he was using a side window to view the rain on the ground the first officer may have been distracted by the captain's statements or by attempts to reduce speed while maintaining the airplane on the correct Glide path that said I guess the question many of you will be asking is how did they ignore the continuous sound of the landing gear warning horn I asked myself that too the reason for this may be that the gear warning horn frequently sounds during routine operations on the dc-9 and it can be perceived by pilots as a nuisance alarm for example people the horn sounds during approaches whenever the throttles are reduced to idle and the landing gear is not down a condition that is not always consistent with a dangerous configuration research has shown that frequent alarms can lead to slower response times or even disregard for a warning in this case however the horn sounded after the gear handle was placed down and the flap handle was moved to 25. these conditions were outside the traditional nuisance envelope the first officer later stated that he did not hear the horn the captain stated that he heard the horn but thought it sounded because he put the flaps to 25 before the gear was down and locked it is possible that the Horn's constant tone lost its salience as a signal in the environment because of the extended duration for which it sounded during the final minute of the approach the safety board concludes that the pilots failed to detect the numerous queues alerting them to the status of the landing gear as a result of their focus on on coping with the flap extension problem and the high level of workload because of the rapid sequence of events in the final minute of the flight a final question worth analyzing is why despite the approach being clearly unstable due to the high speed the pilots decided not to go around the first officer told safety board investigators that his goal after recognizing that the flaps were not extended was to get the captain to initiate a go-around when the captain denied the first officer's request to go around and told him to keep his speed up the first officer did not challenge the captain's statement the first officer's failure to assert himself and clearly challenge the captain's decision to continue the approach must be evaluated in the context of the strategy he had developed after an Airbus a300 incident in 1994 when he was removed from Duty for 60 days and sent to a psychiatrist for evaluation following a captain's complaint the first officer described this incident is terribly damaging to him personally and professionally he told the safety board investigators that he believed his career would be in Jeopardy if another Captain complained to management about him therefore after the incident he adopted a cautious and deferential mode of interaction with captains to prevent a recurrence even though this style of communication could on occasion conflict with the training he had received the captain's rejection without any discussion of the first officer's go-around request was also inconsistent with the training concerning decision-making that he had received the captain stated after the accident that he was aware that the first officer was uncomfortable with the approach but that he felt comfortable continuing with the landing there was no safety reason for the captain to land the airplane and there was sufficient fuel on board to abort the landing and make another approach although the captain referred to an on-time arrival bonus there was no system in place at Continental Airline lines for rewarding Pilots for individual flight performance consequently the safety board concludes that there was no compelling reason for the captain's decision to land the airplane multiple signals and guidance indicated that the approach should be discontinued as did Continental standard operating procedures the captain's improper decision to land was consistent with his behavior during the final 30 minutes of the flight his behavior was that of a passive distracted pilot and not that of an active member of the flight crew ensuring the safety of the flight he repeatedly deviated from standard operating procedures failed to adhere to the sterile cockpit rule ignored warnings and did not utilize effective crew resource management techniques the safety board concluded that the captain's degraded performances consistent with the effects of fatigue but there is insufficient information to determine the extent to which it contributed to the accident following the flight 1994 accident the NTSB made the following recommendation require all dc-9 operators to revise their checklists to emphasize the importance of the Hydraulics item by placing it as the first item on the in-range checklist and to ensure that crew Resource Management Programs provide Pilots with training in recognizing the need for and practice in presenting clear and unambiguous Communications of flight-related concerns thanks for watching if you enjoyed this video please like it and make sure to subscribe to the channel as similar contents are on the way

Channel: Aviation Investigation Channel

Views: 163,082

Keywords: air, crash, investigation, mayday, national, geographic, seconds, disaster, pilot, error, mistake, gear, up, landing, belly, Washington, Houston, COA, 1943, continental, airlines, N10556, flaps, slats, DC, 32, ils, texas, 27, hydraulic, checklist, omitted, master, caution, low, pressure, ntsb, investigator, damaged, beyond, repairs, final, report

Id: ssmHJBM0Qj0

Length: 14min 16sec (856 seconds)

Published: Wed Nov 30 2022