ASN logo
Last updated: 18 November 2018
Status:Final
Date:Wednesday 12 September 1951
Time:10:46
Type:Boeing 377 Stratocruiser 10-34
Operator:United Airlines
Registration: N31230
C/n / msn: 15970/61
First flight: 1949-12-19 (1 year 9 months)
Total airframe hrs:1971
Engines: 4 Pratt & Whitney R-4360-B6
Crew:Fatalities: 3 / Occupants: 3
Passengers:Fatalities: 0 / Occupants: 0
Total:Fatalities: 3 / Occupants: 3
Aircraft damage: Damaged beyond repair
Location:off Redwood City, CA (   United States of America)
Phase: Approach (APR)
Nature:Training
Departure airport:San Francisco International Airport, CA (SFO/KSFO), United States of America
Destination airport:San Francisco International Airport, CA (SFO/KSFO), United States of America
Flightnumber:7030
Narrative:
United Air Lines' Boeing Stratocruiser "Mainliner Oahu" was being used for a semi-annual instrument check of a captain. In addition, consideration had been given to investigating the feasibility of using the Oakland, California, Municipal Airport for certain phases of crew training in this type aircraft for a new class of pilots and flight engineers which was to convene that afternoon. The flight departed at 09:42 and reported on top of the broken scattered clouds four minutes later. The flight proceeded to Oakland, where a simulated ILS approach was carried out, followed by a missed approach procedure. The flight again reported on top at 10:36. Another simulated ILS approach was requested of the Oakland tower but the flight was advised that there would be a delay due to other traffic. In view of this, the pilot decided to return to San Francisco. At 10:39, the flight was cleared for an ILS approach to the San Francisco Airport. The aircraft, with No. 4 propeller feathered, stalled and abruptly dived from an altitude of approximately 300 feet and was demolished upon impact in San Francisco Bay.

Probable Cause:

PROBABLE CAUSE: "An inadvertent stall at a low altitude from which recovery was not effected."

Classification:
Loss of control

Sources:
» CAB File No. 1-0089


Photos

Add your photo of this accident or aircraft

Map

languages: languages

Share

Boeing 377

  • 56 built
  • The first loss
  • The first fatal accident
  • The worst accident (at the time)
  • 6th worst accident (currently)
» safety profile