Date: February 19, 1985
Type: Boeing 747-SP
Registration: N4522V
Operator: China Airlines
Where: San Francisco, California
Report No. NTSB-AAR-86-03
Report Date: March 29, 1986
Pages: 48

A Boeing 747 SP-O9, enroute to Los Angeles, California from Taipei, 
Taiwan, suffered an inflight upset. The flight from Taipei to about 300 
nmi northwest of San Francisco was uneventful and the airplane was flying 
at about 41,000 feet mean sea level when the No. 4 engine lost power. 
During the attempt to recover and restore normal power on the No. 4 
engine, the airplane rolled to the right, nosed over, and entered an 
uncontrollable descent.  The captain was unable to restore the airplane 
to stable flight until it had descended to 9,500 feet. After the captain 
stabilized the airplane, he elected to divert to San Francisco 
International Airport, where a safe landing was made. Although the 
airplane suffered major structural damage during the upset, descent, and 
subsequent recovery, only 2 persons among the 274 passengers and crew on 
board were injured seriously.

The National Transportation Safety Board determines that the probable 
cause of this accident was the captain's preoccupation with an inflight 
malfunction and his failure to monitor properly the airplane's flight 
instruments which resulted in his losing control of the airplane.

Contributing to the accident was the captain's over-reliance on the 
autopilot after the loss of thrust on the No. 4 engine.