The National Transportation Safety Board (NTSB) is 
United Airlines
The Boeing 757 incident occurred in September 2024. The agency determined that two passengers were injured when United Airlines' Boeing 757 experienced sudden pitch control issues.
what happened?
On September 19, 2024, United Airlines Boeing 757-200 aircraft, registered as N12125, operated UA 2428 from Newark International Airport (EWR). San Francisco International Airport
(SFO), when the aircraft receives a traffic alert and Collision Avoidance System (TCAS) resolution advisor while the aircraft is descending on flight level FL310 on its way to the SFO.
Photo: Michael Gordon | Shutterstock
Air Traffic Control (ATC) has instructed the Boeing 757 flight crew to descend and level with the FL310 to arrive at the SFO. Approximately 500 feet before reaching the FL310, the crew received the TCAS traffic alert warning “Traffic, Traffic” and passed the aircraft 1,500 feet below. In response, the first mate, who was flying the aircraft, used the mode control panel to reduce the vertical speed.
The first mate unplugged the autopilot and automatic throttle and threw the aircraft upward following pitch guidance on the primary flight display. The flight crew responded to the TCAS alert in what the NTSB calls “sudden pitch control input.” In that report, ntsb
description:
“The National Transportation Safety Board determines the possible cause of this accident. The sudden pitch control input by the flight attendant in response to the TCAS resolution recommendations resulted in two serious passenger injuries.”
According to data from PlaneSpotters.net, the aircraft in question is the airline's 27.2-year-old Boeing 757-200 aircraft. According to data, the aircraft is currently in storage
Maintained damage to the ankle and spinal vertebrae
As a result, two passengers were seriously injured and two cabin crew members were minor injuries.
The seat belt sign had been activated in the cabin just before the TCAS alert, but some passengers were still in the bathroom during operation. One passenger flew upwards and advanced, destroying the L2 spinal vertebrae. Other passengers had left the bathroom when he flew upwards and landed on his leg, breaking his ankle.
Photo: Vincenzo Pace | Simple Flying
Meanwhile, two flight attendants were cleaning the galley ahead in preparation for the announcement of the first descent. These two cabin crew members fell to the floor while piloting and suffered minor injuries.
Related
Understanding the TCAS Advisory: How Two Passengers Are Injured on a Recent United Flight
The incident occurred at 31,000 feet.
Details of TCA
Safety is the most important thing in all aviation, so many steps have been taken to keep the aircraft away from the air. One such example is an independent collision avoidance system known as TCAS.
TCAS stands for traffic collision avoidance system, and its purpose is to minimize the risk of airborne collisions between aircraft. ICAO must equip all aircraft with the capacity of more than 19 passengers with this safety measure. This rule also applies to aircraft with a maximum takeoff weight (MTOW) of 5,700 kg or more.
Working independently of air traffic control, TCAS uses transponder signals from nearby aircraft to alert pilots of the risk of an airborne collision. This is done by constructing a three-dimensional map of the airspace in which the aircraft is traveling. When detecting transponder signals from other aircraft, potential collisions can be predicted based on the speed and altitude of the plane passing through the airspace in question.
If TCAS detects a potential collision, each affected aircraft will be automatically notified. In this example, a mutual avoidance operation will be started automatically. For more information about the TCAS system, see the complete Simple Flying guide below.
Related
What is TCA? How does it work?
See how technology helps prevent aircraft from getting too close to each other.
