B777 crew had autoflt and autothrottle anomalies in egcc class B airspace.

Attributes
ACN	480293
Time
Date	200007
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : egcc.airport
State Reference	FO
Altitude	msl bound lower : 4000 msl bound upper : 4150
Environment
Flight Conditions	Mixed
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	B777 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	ils localizer & glide slope : 06l other other
Flight Phase	descent : approach descent : intermediate altitude
Route In Use	arrival : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 16000 flight time type : 800
ASRS Report	480293
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Events
Anomaly	aircraft equipment problem : less severe other anomaly other
Independent Detector	other flight crewa other flight crewb
Resolutory Action	flight crew : returned to assigned altitude other
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

The event did/does not involve any aircraft/ATC violation. The scenario is related solely for advisory of FMC malfunction. Final approach to runway 6L, man, uk, cleared to descend from FL090 to 4000 ft. Flight level change selected on autoplt, first officer flying. At +-4500 ft, captain and first officer set local altimeter of 1025 hectopascals. ATC issued speed reduction to 210 KTS, flaps 1 degree selected. 'Speed' and 'flight level change' annunciation on FMA. A yellow box appeared around first officer and captain altimeter indicating window and aircraft leveled off at 4150 ft. Crew then noted 'altitude hold' button illuminated. First officer reselected flight level change, aircraft still did not descend to 4000 ft. At this time both captain and first officer observed airspeed decelerate below 190 KTS, autothrottle engaged, speed in MCP set to 210 KTS, flight level change selected. ATC was vectoring toward localizer intercept and requested 'report established.' first officer added power, requested 'flaps 5 degrees' and announced 'autoplt coming off.' aircraft was hand flown down to 4000 ft and accelerated to 210 KTS. Yellow box around altimeter indicator window disappeared and after approximately 60 seconds, autoplt re-engaged (selected) and aircraft resumed normal speed and altitude (GS tracking) control. Less attention to situational awareness or an increased distraction level could have resulted in a mishap.

Original NASA ASRS Text

Title: B777 CREW HAD AUTOFLT AND AUTOTHROTTLE ANOMALIES IN EGCC CLASS B AIRSPACE.

Narrative: THE EVENT DID/DOES NOT INVOLVE ANY ACFT/ATC VIOLATION. THE SCENARIO IS RELATED SOLELY FOR ADVISORY OF FMC MALFUNCTION. FINAL APCH TO RWY 6L, MAN, UK, CLRED TO DSND FROM FL090 TO 4000 FT. FLT LEVEL CHANGE SELECTED ON AUTOPLT, FO FLYING. AT +-4500 FT, CAPT AND FO SET LCL ALTIMETER OF 1025 HECTOPASCALS. ATC ISSUED SPD REDUCTION TO 210 KTS, FLAPS 1 DEG SELECTED. 'SPD' AND 'FLT LEVEL CHANGE' ANNUNCIATION ON FMA. A YELLOW BOX APPEARED AROUND FO AND CAPT ALTIMETER INDICATING WINDOW AND ACFT LEVELED OFF AT 4150 FT. CREW THEN NOTED 'ALT HOLD' BUTTON ILLUMINATED. FO RESELECTED FLT LEVEL CHANGE, ACFT STILL DID NOT DSND TO 4000 FT. AT THIS TIME BOTH CAPT AND FO OBSERVED AIRSPD DECELERATE BELOW 190 KTS, AUTOTHROTTLE ENGAGED, SPD IN MCP SET TO 210 KTS, FLT LEVEL CHANGE SELECTED. ATC WAS VECTORING TOWARD LOC INTERCEPT AND REQUESTED 'RPT ESTABLISHED.' FO ADDED PWR, REQUESTED 'FLAPS 5 DEGS' AND ANNOUNCED 'AUTOPLT COMING OFF.' ACFT WAS HAND FLOWN DOWN TO 4000 FT AND ACCELERATED TO 210 KTS. YELLOW BOX AROUND ALTIMETER INDICATOR WINDOW DISAPPEARED AND AFTER APPROX 60 SECONDS, AUTOPLT RE-ENGAGED (SELECTED) AND ACFT RESUMED NORMAL SPD AND ALT (GS TRACKING) CTL. LESS ATTN TO SITUATIONAL AWARENESS OR AN INCREASED DISTR LEVEL COULD HAVE RESULTED IN A MISHAP.

Data retrieved from NASA's ASRS site as of July 2007 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.