Service difficulty report · Selector Valve · Boeing 747122

Difficulty date
December 26, 1996
Submitted
March 26, 2000
Operation
Air carrier
Aircraft
N4732U
Make and model
Boeing 747122
Aircraft serial
19927
Engine
Pwa JT9D7A
Part
Selector Valve
Part number
366103
Condition
Cracked
Location
Nlg Steering
Stage of operation
LD
Nature of condition
K, J
Precautionary procedure
O

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

ON LANDING HYDRAULIC SYSTEM NR 1 QUANTITY WENT TO ZERO. PRESSURE LIGHT CAME ON FOR AIR PUMP AND ENGINE PUMP. TAXIED OFF RUNWAY AND WAS TOWED TO THE GATE DUE TO LOSS OF BODY AND NOSE LANDING GEAR STEERING. *S/D* LOSS OF HYDRAULIC FLUID WAS DUE TO CRACKED BODY/NOSE LANDING GEAR SELECTOR VALVE WHICH CAUSED THE ENGINE DRIVEN PUMP TO FAIL. REPLACED VALVE, ENGINE DRIVEN PUMP AND CASE DRAIN FILTER.