v5p1374b

Report of the PRESIDENTIAL COMMISSION on the Space Shuttle Challenger Accident

Volume 5 Index

Hearings of the Presidential Commission on the Space Shuttle Challenger Accident: February 26, 1986 to May 2, 1986.

MARCH 21, 1986 SESSION. (part 2 of 2)

[1374] [Ref. 3/21-76 1 of 2] O-Ring Erosion Analysis.

O-RING EROSION ANALYSIS

MARCH 21, 1986

G.M. LITTLES

[1375] [Ref. 3/21-76 2 of 2] Erosion Scenario.

EROSION SCENARIO

GAS IMPINGEMENT EROSION
- GAS JET PENETRATES VACUUM PUTTY AND IMPINGES ON PRIMARY SEAL

- SEAL EROSION CONTINUES UNTIL PRESSURE IN CAVITY BETWEEN SEAL AND PUTTY EQUALS ROTOR CHAMBER STATIC PRESSURE
BLOW-BY EROSION
- GAS JET PENETRATES VACUUM PUTTY AND BLOWS BY PRIMARY SEAL

- PRIMARY SEAL ERODES DUE TO CONVECTIVE HEATING AND SECONDARY SEAL ERODES DUE TO GAS IMPINGEMENT UNTIL PRESSURE OF THE CAVITY BETWEEN PRIMARY AND SECONDARY SEALS EQUALS THE PRIMARY SEAL CAVITY PRESSURE