Investigation Summary
Flight 297 was the first leg of a multi-stop service to Atlanta. While level at 6,000 feet following a descent from 10,000 feet, air traffic controllers warned the crew of numerous reports of large birds in the area. Shortly after acknowledging a heading change, the aircraft struck at least two whistling swans. One bird caused minor damage to the right stabilizer, but a second bird crashed entirely through the left horizontal stabilizer. The structural damage was so severe that the stabilizer separated from the airframe in flight. The Vickers Viscount design was particularly vulnerable because its high-mounted tailplane sat above the protective wash of the propellers, leaving it exposed to direct impacts. The resulting loss of pitch control caused the aircraft to dive into a wooded area, where a post-crash fire consumed much of the remaining fuselage.
Final Conclusions
The Civil Aeronautics Board (CAB) released its final report on March 22, 1963, concluding the probable cause was the loss of control following the separation of the left horizontal stabilizer, which had been weakened by a collision with a whistling swan. The investigation highlighted that existing bird-strike certification standards, which focused primarily on windshields, were insufficient for the higher speeds and tail designs of modern turboprop and jet aircraft.
Photographic Evidence (1)
Video Analysis
United Airlines Flight 297 Aftermath Footage | 23 November 1962 Ellicott City, Maryland — Historical aftermath footage and accident description of the Vickers Viscount crash caused by a whistling swan strike over Maryland.
If playback is blocked, the owner has disabled embedding — use the link above.
Airframe & Maintenance
Systems & Failure Modes
Horizontal Stabilizer
A critical tail surface providing longitudinal stability; its failure led to an immediate loss of pitch control.
Empennage
The tail assembly of the aircraft, which on the Viscount 745D was positioned above the propeller line, leaving it unshielded from bird impacts.
Interesting Facts
- 01The birds involved were identified as whistling swans, which can weigh over 18 pounds (8 kg).
- 02The left horizontal stabilizer was found a quarter of a mile away from the main wreckage site.
- 03Six of the thirteen passengers were off-duty United Airlines employees.
- 04The aircraft was originally owned by Capital Airlines before its merger with United in 1961.
- 05During the uncontrolled descent following the initial strike, the right horizontal stabilizer and elevator also failed and separated from the aircraft.
Safety Actions & Advisories
CFR Section 25.631
In 1970, the FAA implemented new regulations requiring the empennage structure of transport category aircraft to be designed to withstand an impact with an eight-pound bird at cruising speed.