B777 captain reported a primary flaps failure and ran the appropriate checklist. They opted to devia...

Narrative:

Landing south in ZZZ; ATC near capacity; busy night. Given a number of speed assignments during our arrival; and we had slowed to 210 kts by 40 NM from field. On base leg to final; runway xxl; we were assigned 160 kts. Our ZFW of 505;000 lbs required 30 flaps to go below 165 kts; so we asked to stay at 165 and were cleared for that; initially. On dogleg to final; still approximately 20 miles to touchdown; we were assigned 160 kts to 5 NM final. Lowered the gear and as we selected 30 flaps we got an EICAS alert 'primary flaps fail'. We ran the non-normal checklist and noted that the flaps were extending beyond 25 as we read the checklist. By the time we finished the checklist; we were configured with gear down and flaps 30; with field in sight and intercepting the glideslope. All indications for the approach were normal; autopilot was engaged and the aircraft was stabilized. As pilot monitoring; I made the decision to continue the approach as I considered it a safer course of action than discontinuing approach at that point; especially since we were on final. I elected also to leave the flaps at 30 instead of trying to raise them to 20 at that point; confident that the aircraft in that configuration had more than enough go-around performance. First officer was pilot flying and continued the stabilized approach to an uneventful landing.submitting this report because after completing the 'primary flaps fail' checklist; I determined it safer to remain in current; stabilized configuration for landing than to try and raise the flaps via alternate means to the recommended configuration of flaps 20. Weather was clear and we were confident that the aircraft had more than sufficient go-around capability.our option was to discontinue the approach; request vectors and reset the flaps from 30 to 20. With the traffic load on approach; we determined it safer to continue to landing. I don't think this type of event can be prevented; as it was an aircraft system malfunction. If the weather was questionable; or if there was any question of go-around performance due to terrain we would have definitely discontinued the approach and reconfigured the aircraft.

Original NASA ASRS Text

Title: B777 Captain reported a primary flaps failure and ran the appropriate checklist. They opted to deviate from the checklist and land with more flaps than the checklist dictated.

Narrative: Landing south in ZZZ; ATC near capacity; busy night. Given a number of speed assignments during our arrival; and we had slowed to 210 kts by 40 NM from field. On base leg to final; Runway XXL; we were assigned 160 kts. Our ZFW of 505;000 lbs required 30 flaps to go below 165 kts; so we asked to stay at 165 and were cleared for that; initially. On dogleg to final; still approximately 20 miles to touchdown; we were assigned 160 kts to 5 NM final. Lowered the gear and as we selected 30 flaps we got an EICAS alert 'PRIMARY FLAPS FAIL'. We ran the non-normal checklist and noted that the flaps were extending beyond 25 as we read the checklist. By the time we finished the checklist; we were configured with gear down and flaps 30; with field in sight and intercepting the glideslope. All indications for the approach were normal; autopilot was engaged and the aircraft was stabilized. As Pilot Monitoring; I made the decision to continue the approach as I considered it a safer course of action than discontinuing approach at that point; especially since we were on final. I elected also to leave the flaps at 30 instead of trying to raise them to 20 at that point; confident that the aircraft in that configuration had more than enough go-around performance. FO was pilot flying and continued the stabilized approach to an uneventful landing.Submitting this report because after completing the 'Primary Flaps Fail' checklist; I determined it safer to remain in current; stabilized configuration for landing than to try and raise the flaps via alternate means to the recommended configuration of flaps 20. Weather was clear and we were confident that the aircraft had more than sufficient go-around capability.Our option was to discontinue the approach; request vectors and reset the flaps from 30 to 20. With the traffic load on approach; we determined it safer to continue to landing. I don't think this type of event can be prevented; as it was an aircraft system malfunction. If the weather was questionable; or if there was any question of go-around performance due to terrain we would have definitely discontinued the approach and reconfigured the aircraft.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Attributes
ACN	1421407
Time
Date	201702
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Make Model Name	B777-200
Operating Under FAR Part	Part 121
Flight Phase	Initial Approach
Route In Use	Vectors
Flight Plan	IFR
Component
Aircraft Component	Trailing Edge Flap
Person 1
Function	Captain Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Less Severe Deviation - Procedural Published Material / Policy

B777 captain reported a primary flaps failure and ran the appropriate checklist. They opted to deviate from the checklist and land with more flaps than the checklist dictated.