Casualties unknown

Sightseeing Aircraft Collides with Telephone Pole After Encountering Downdrafts (N56856)

Big Bear, CA, US

On August 29, 1998, a Boeing Stearman A75N1 (registration N56856) operated by Twin-d Enterprises Inc was involved in an aviation accident near Big Bear, CA. Investigators recorded the probable cause as: The pilot's encounter with an unfavorable wind condition, which caused the aircraft to descend at a rate that exceeded the aircraft's climb capability. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 2026-07-04Data APIEditorial standards

A for-hire sightseeing aircraft, part of a two-ship formation, encountered downdrafts on crosswind leg, turned left, recovered near ground, struck a telephone pole, and inverted. Postimpact fire destroyed the aircraft. No mechanical anomalies were found.

Accident Sequence

The aircraft was one of two conducting for-hire sightseeing flights from the airport. After turning onto the crosswind leg, both aircraft encountered downdrafts. The accident aircraft turned left while the trailing aircraft turned right. The accident aircraft recovered close to the ground, collided with a telephone pole, and came to rest inverted.

Aircraft Examination

Postaccident examination established control continuity. No mechanical anomalies were noted. The pilot reported no mechanical anomalies during the flight, stating the aircraft was at full power but not gaining altitude. This was the sixth flight of the day, with no discrepancies recorded on previous flights.

Weather Conditions

At the time of the accident, weather was deteriorating. A witness reported rain showers approximately 5 miles southeast of the airport. Meteorological data indicated the presence of instability and convective activity conducive to up and downdrafts near the accident site.

Damage

The aircraft was destroyed by a postimpact fire.

Frequently asked questions

What happened in the 29 Aug 1998 Boeing Stearman A75N1 accident near Big Bear, CA?

A for-hire sightseeing aircraft, part of a two-ship formation, encountered downdrafts on crosswind leg, turned left, recovered near ground, struck a telephone pole, and inverted. Postimpact fire destroyed the aircraft. No mechanical anomalies were found.

What aircraft was involved and where did it happen?

The accident on 29 Aug 1998 involved a Boeing Stearman A75N1, registration N56856, operated by Twin-d Enterprises Inc, at Big Bear, CA.

What was the probable cause of the accident?

The pilot's encounter with an unfavorable wind condition, which caused the aircraft to descend at a rate that exceeded the aircraft's climb capability.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001211X10908. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.