Service difficulty report · Actuator · Boeing 7474B5

Difficulty date
November 12, 2025
Submitted
November 25, 2025
Operation
Air carrier
Aircraft
N708CK
Make and model
Boeing 7474B5
Aircraft serial
25275
Aircraft time
116,252 hours, 19,861 cycles
Part
Actuator
Part number
1U11937
Part serial
3767
Condition
Unserviceable
Location
Zone 700
Stage of operation
CL
How discovered
O
Nature of condition
J
Precautionary procedure
A

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

What was found

GEAR DOOR ACTION TAKEN: REMOVED & REPLACED RH BODY LANDING GEAR DOOR ACTUATOR IAW B747-400 AMM 32-33-27. GEAR DOOR REMAINED INOP. SEE SDR SECTION 5. SPECIFIC PART OR STRUCTURE CAUSING DIFFICULTY FOR OFF PART INFORMATION. PN ON 1U1193-7 SN ON 3849. REF GEAR DOOR #100281064, R & R BODY GEAR ALT-EXT ACTUATOR ROTARY IAW B747-400 AMM 32-35-01. PERFORMED OPS CHECK IAW B747-400 AMM 32-35-00. OPS CHECK GOOD. PN OFF 1387T100-5 SN OFF 1346 PN ON 1387T100-11 SN ON 4438. RT BODY GEAR DOOR BUMP STOP MISSING BOLT ACTION TAKEN: INSTALLED TEMP SCREW IAW B747-400 SRM CHAPT 51-40 AND E-50. MUST BE REPLACED WITHIN 10 FLIGHT CYCLES. REF WO #100281066 RH BODY GEAR DOOR BUMP STOP MISSING SCREW. ACTION TAKEN: APPROVED FOR COI #100281067 IAW E-50 EVENT 16406. TEMP SCREW MUST BE REPLACED WITH IN 10 FC. INFLATED STRUT TO OPEN GEAR DOOR. ACTION TAKEN: APPROVED FOR COI #100281068 INSPECT R/H BODY GEAR STRUT IAW B747-400 AMM 12-15-04. PER GMM 3.1.19 RECHECK DUE BETWEEN 5 & 10 CYCLES. REFERENCE COI #100281068 RH BODY GEAR STRUT. ACTION TAKEN: INSPECTED RH BODY GEAR STRUT IAW B747-400 AMM 12-15-04, PER GMM 3.1.19. FOUND TO BE WITHIN LIMITS. THIS CLEARS COI. REF COI 100281067 TEMP SCREW INSTALLED. ACTION TAKEN: REMOVED AND REPLACED TEMP SCREW IN RH BODY GEAR DOOR BUMP STOP THIS CLEARS COI 100281067.

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