Service difficulty report · Dump Valve · Gulstm GIVXG450

Difficulty date
June 27, 2026
Submitted
July 2, 2026
Operation
Air carrier
Aircraft
N421QS
Make and model
Gulstm GIVXG450
Aircraft serial
4114
Aircraft time
12,636 hours, 6,267 cycles
Part
Dump Valve
Part number
1159SCH51219
Part serial
EFS0495A
Condition
Malfunctioned
Location
Zone 700
Stage of operation
AP
How discovered
O
Nature of condition
J
Precautionary procedure
L

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

What was found

ON APPROACH TO KAPF AND UPON SELECTING GEAR DOWN, CREW RECEIVED 'NOSE GEAR NOT DOWN' AND 'L-R MAIN GEAR NOT DOWN CAS' MESSAGE, FOLLOWED BY A 'L HYDRAULIC QUANTITY LOW CAS' MESSAGE. COMPLETED THE LANDING GEAR FAILED TO EXTEND CHECKLIST, THAT INSTRUCTED TO USE THE EMERGENCY GEAR EXTENSION PROCEDURE, AND RECEIVED A SUCCESSFUL GEAR EXTENSION INDICATION. CREW DECLARED AN EMERGENCY AND PERFORMED AN UNEVENTFUL LANDING. MAINTENANCE EVALUATION FOUND FAILED LANDING GEAR SELECTOR/DUMP VALVE.