A United Airlines Boeing 777-200 that had just taken off from Maui Airport in Hawaii bound for San Francisco last December plunged 1,425 feet in just a few seconds and came within 748 feet of hitting the Pacific Ocean because the First Officer misheard instructions given to him by the Captain an NTSB investigation has concluded.
Following the horrifying incident, United Airlines didn’t bother to report the event but the National Transportation Safety Board (NTSB) decided to open its own investigation after learning of the circumstances some two months later.
By this point, data from the cockpit voice recorder and flight data recorder had already been wiped, but the NTSB was able to piece together what happened after the Captain and First Officer agreed to provide interviews to investigators.
It turns out that the terrifying incident unfolded after the First Officer misheard just one word in a set of instructions given by the Captain.
The instruction related to the settings of the flaps – panels that extend from the wings of an airplane and help increase the lift generated by the wings, allowing a plane to take off and land at slower speeds.
On takeoff from Maui, the Captain had set the flaps to a setting of 20 but during the climb, the airplane started shaking because of turbulence in the air, causing the speed of the plane to go up and down.
The Captain, who had more than 19,600 hours of flying experience at the time of the incident on December 18, 2022, asked the First Officer to adjust the flap setting to 5 in order to make the aircraft more streamlined.
But the First Officer told investigators he mistakenly thought the Captain had asked for the flaps to be set to setting 15. This caused the speed of the plane to go up too quickly and at this point, the Captain started to figure out what was going on and again asked the co-pilot to adjust the flap setting to 5.
On this occasion, the First Officer heard the Captain’s correct command and set the flap setting accordingly.
Following the incident, United Airlines aid it closely coordinated with the Federal Aviation Administration (FAA) and the ALPA pilots union, and this resulted in both pilots receiving additional training.
A spokesperson for the airline said: “Safety remains our highest priority”.
The NTSB has confirmed that none of the 281 passengers and crew onboard United flight UA1722 were injured and the aircraft was not damaged. The whole incident was over in only 45 seconds.
