FlarePath

What happened

NTSB summary, verbatim

On November 10, 2011, at about 1157 central standard time, Delta flight 1691, an A320-211, N331NW, experienced a bird strike during initial climb after departure from Minneapolis-St. Paul International Airport (KMSP), Minneapolis, Minnesota. There were no injuries to the 150 passengers and crewmembers onboard and the airplane was substantially damaged. The flight was operating as a 14 Code of Federal Regulations Part 121 regularly scheduled passenger flight from KMSP to Reno–Tahoe International Airport (KRNO), Reno, Nevada. According to the flight crew, a flock of "50-100" large white birds, possibly geese, appeared in front of the airplane during initial climb. The first officer, who was the pilot flying, increased the rate of climb to attempt to avoid the flock, but at least one bird made impacted the aircraft. After striking the bird, the flight crew received an Electronic Centralized Aircraft Monitor message for loss of cabin pressure and the right side airspeed indication became erratic. The flight crew declared an emergency and made an uneventful landing back at KMSP. Examination of the aircraft after landing revealed substantial damage to the forward pressure bulkhead and minor damage to the right engine.

Photographs

4the aircraft, and what the investigators found

The aircraft before the accident

Wreckage and site documentation · 3 photographs from the docket

Photographs are NTSB docket attachments — works of the US government, in the public domain. Captions are the Board’s own.

Probable cause

the Board's determination

In-flight collision with birds during initial climb, which resulted in substantial damage to the aircraft.

Occurrence sequence

1 stepsNTSB coding · CICTT taxonomy

1 · Initial climb
Birdstrike
defining event

Findings

1 causal · 0 contributing

CAUSE
Environmental issues › Physical environment › Object/animal/substance › Animal(s)/bird(s) — Effect on equipment

Sequence of events

4 timed eventsfrom the FDR factual report · claude-fable-5-1 (in-session)

11:39 CSTtakeoffp.3
Aircraft departed Minneapolis
11:40:58 CSTclimbp.3
Climbing through approximately 3,400 ft, a vertical acceleration spike of 1.527 g was recorded while pitch increased from about 6 degrees to 16.2 degrees nose up (bird strike)
after 11:40:58 CSTreturnp.3
Aircraft leveled at about 4,000 ft before returning to the airport
11:58 CSTlandingp.3
Landed at Minneapolis

NTSB analysis

from the final report

On November 10, 2011, at about 1157 central standard time, Delta flight 1691, an A320-211, N331NW, experienced a bird strike during initial climb after departure from Minneapolis-St. Paul International Airport (KMSP), Minneapolis, Minnesota. There were no injuries to the 150 passengers and crewmembers onboard and the airplane was substantially damaged. The flight was operating as a 14 Code of Federal Regulations Part 121 regularly scheduled passenger flight from KMSP to Reno–Tahoe International Airport (KRNO), Reno, Nevada. According to the flight crew, a flock of "50-100" large white birds, possibly geese, appeared in front of the airplane during initial climb. The first officer, who was the pilot flying, increased the rate of climb to attempt to avoid the flock, but at least one bird made impacted the aircraft. After striking the bird, the flight crew received an Electronic Centralized Aircraft Monitor message for loss of cabin pressure and the right side airspeed indication became erratic. The flight crew declared an emergency and made an uneventful landing back at KMSP. Examination of the aircraft after landing revealed substantial damage to the forward pressure bulkhead and minor damage to the right engine.

AIRBUS INDUSTRIE A320 211DELTA AIR LINES INC