A B737 crew reports a flap asymmetry with flaps at 5DEGS. This aircraft had the same problem earlier...

Attributes
ACN	813937
Time
Date	200811
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	msl single value : 4000
Environment
Flight Conditions	VMC
Aircraft 1
Controlling Facilities	tower : zzz.tower
Operator	common carrier : air carrier
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Experience	flight time last 90 days : 160 flight time total : 6000 flight time type : 3000
ASRS Report	813937
Person 2
Affiliation	company : air carrier
Function	flight crew : captain observation : company check pilot oversight : pic
Experience	flight time last 90 days : 210 flight time total : 10000 flight time type : 6000
ASRS Report	813945
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	aircraft equipment other aircraft equipment : flap gage other flight crewa other flight crewb
Resolutory Action	flight crew : landed in emergency condition flight crew : declared emergency
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

On a 10 mi final to runway 27 ZZZ; the flaps were lowered to 10 degrees; the flaps stopped at 5 degrees. I was flying the plane and the captain ran all the checklists with a jumpseater backing him up. The checklist procedure did not fix the flap problem. Then; per the checklist; the captain calculated speeds and landing distance and all was good to go for runway 27. I flew ATC vectors during this time and we declared an emergency and passed on all appropriate information to ATC and dispatch. I then did my own numbers to make sure the captain and I came up with the same numbers; we did. The captain briefed the cabin crew but did not prep the cabin. The plane was landed with flaps 5 degrees and slats at 'extend.' the landing was uneventful. After clearing runway 27 the fire department checked for hot brakes. Brakes were good and we taxied the plane to gate and deplaned normally. There were no human factors. All air carrier procedures and checklists were followed. Supplemental information from acn 813945: this malfunction happened to the same airplane this morning at ZZZ1. I received the plane from the pilots at ZZZ2 that had flown it from ZZZ1-ZZZ2-ZZZ1 earlier. They cycled the circuit breakers; as we did; but got control of the flaps and landed normally. The flaps worked normally on their return leg from ZZZ2 to ZZZ1. I thought it was just a 1 time event; as happens with old airplanes.

Original NASA ASRS Text

Title: A B737 CREW REPORTS A FLAP ASYMMETRY WITH FLAPS AT 5DEGS. THIS AIRCRAFT HAD THE SAME PROBLEM EARLIER IN THE DAY. AN EMERGENCY WAS DECLARED FOLLOWED BY A NORMAL LANDING.

Narrative: ON A 10 MI FINAL TO RWY 27 ZZZ; THE FLAPS WERE LOWERED TO 10 DEGS; THE FLAPS STOPPED AT 5 DEGS. I WAS FLYING THE PLANE AND THE CAPT RAN ALL THE CHKLISTS WITH A JUMPSEATER BACKING HIM UP. THE CHKLIST PROC DID NOT FIX THE FLAP PROB. THEN; PER THE CHKLIST; THE CAPT CALCULATED SPDS AND LNDG DISTANCE AND ALL WAS GOOD TO GO FOR RWY 27. I FLEW ATC VECTORS DURING THIS TIME AND WE DECLARED AN EMER AND PASSED ON ALL APPROPRIATE INFO TO ATC AND DISPATCH. I THEN DID MY OWN NUMBERS TO MAKE SURE THE CAPT AND I CAME UP WITH THE SAME NUMBERS; WE DID. THE CAPT BRIEFED THE CABIN CREW BUT DID NOT PREP THE CABIN. THE PLANE WAS LANDED WITH FLAPS 5 DEGS AND SLATS AT 'EXTEND.' THE LNDG WAS UNEVENTFUL. AFTER CLRING RWY 27 THE FIRE DEPT CHKED FOR HOT BRAKES. BRAKES WERE GOOD AND WE TAXIED THE PLANE TO GATE AND DEPLANED NORMALLY. THERE WERE NO HUMAN FACTORS. ALL ACR PROCS AND CHKLISTS WERE FOLLOWED. SUPPLEMENTAL INFO FROM ACN 813945: THIS MALFUNCTION HAPPENED TO THE SAME AIRPLANE THIS MORNING AT ZZZ1. I RECEIVED THE PLANE FROM THE PLTS AT ZZZ2 THAT HAD FLOWN IT FROM ZZZ1-ZZZ2-ZZZ1 EARLIER. THEY CYCLED THE CIRCUIT BREAKERS; AS WE DID; BUT GOT CTL OF THE FLAPS AND LANDED NORMALLY. THE FLAPS WORKED NORMALLY ON THEIR RETURN LEG FROM ZZZ2 TO ZZZ1. I THOUGHT IT WAS JUST A 1 TIME EVENT; AS HAPPENS WITH OLD AIRPLANES.

Data retrieved from NASA's ASRS site as of May 2009 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.

A B737 crew reports a flap asymmetry with flaps at 5DEGS. This aircraft had the same problem earlier in the day. An emergency was declared followed by a normal landing.