Boeing 767-322 N647UA accident near Gulf Of America, GM

Probable cause

An encounter with an area of clear air turbulence during cruise, which resulted in a serious injury to a flight attendant.

NTSB analysis

United Airlines flight 854, operating between George Bush Intercontinental / Houston Airport (IAH), Houston, Texas, and Jorge Chávez International Airport (LIM), Lima, Peru, encountered moderate turbulence while in cruise. One flight attendant sustained a serious injury during the turbulence encounter.

The captain served as the flying pilot and the first officer as the pilot monitoring for the entire flight. Prior to the flight, the crew reviewed the dispatch release and weather forecasts, which indicated areas of light to moderate turbulence along the route, and no other significant turbulence risks were identified along their route.

After a standard pushback, taxi, and takeoff, the aircraft climbed to cruise altitude. About one hour after reaching cruise altitude, the crew anticipated encountering turbulence ahead based on the SkyPath and Weather Services International (WSI) electronic depictions of turbulence potential along their route. The captain contacted the purser approximately ten minutes before the expected turbulence and advised that the “flight attendants, please take your jump seats” announcement would be made in five minutes. This was followed by a public announcement (PA) to passengers and crew regarding the expected turbulence and the need for flight attendants to be seated soon.

Five minutes later, the captain made the “flight attendants, please take your jump seats” PA to the cabin. Shortly thereafter, the aircraft encountered light turbulence that quickly escalated to moderate. The turbulence lasted approximately 25–30 minutes, with intermittent light turbulence continuing for an additional 15–20 minutes.

The three cabin crew members working in the rear of the aircraft reported that, following the “flight attendants, please take your jump seats” announcement, they attempted to move their service carts to the aft galley and secure their equipment. However, turbulence began before they could fully stow the carts, leaving them only able to park the carts in the galley without securing them back into their slots. While one flight attendant stated that while they were attempting to prevent a cart from tipping over, the airplane experienced a “big shake”. The flight attendant was thrown to the floor, striking her back against the edge of a jumpseat before falling to the floor. The flight attendant was able to secure themselves in a jumpseat for the remainder of the turbulence encounter.

Following the turbulence, the captain made a “flight attendants, please check in” PA, and the purser initially reported that all was well. However, later the purser informed the cockpit that a flight attendant had fallen in the aft galley during the turbulence. The captain visited the injured flight attendant, who reported lower back pain but stated they were fit to continue duties.

The crew contacted dispatch via satellite communications and given the flight attendant’s ability to continue working, they elected to continue to LIM without diversion and decided no further Medlink action was necessary. The approach and landing into Lima were normal.

After deplaning, the captain spoke with the injured flight attendant, who again declined medical attention, and was able to depart the flight and airport without assistance. However, when the injured flight attendant returned to Houston, the they were medically examined, and it was determined that they had sustained fractures of two vertebrae.

Text from the NTSB. Open the NTSB docket for DCA25LA091 for the full record.