An MD10-10 cockpit door would not unlock normally to allow captain to return to the cockpit. First o...

Attributes
ACN	639921
Time
Date	200412
Day	Fri
Local Time Of Day	0001 To 0600
Place
Locale Reference	atc facility : zjx.artcc
State Reference	FL
Altitude	msl single value : 33000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	artcc : zjx.artcc
Operator	common carrier : air carrier
Make Model Name	MD-10 Conversion
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : multi engine pilot : flight engineer pilot : cfi pilot : atp
Experience	flight time last 90 days : 100 flight time total : 16500 flight time type : 800
ASRS Report	639921
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument pilot : multi engine pilot : atp
Experience	flight time last 90 days : 150 flight time total : 5000 flight time type : 1950
ASRS Report	639745
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	other flight crewa other flight crewb
Resolutory Action	flight crew : overcame equipment problem
Consequence	other other
Supplementary
Problem Areas	Aircraft Chart Or Publication Environmental Factor Flight Crew Human Performance Maintenance Human Performance
Primary Problem	Aircraft

Narrative:

Captain left the flight deck for lavatory. Upon return, signaled the first officer with standard 'code' combination for cockpit re-entry. First officer placed the magnetic door control switch to the un-locked position. Green 'entry' light illuminated on keypad in supernumerary area, but captain was unable to open the door. After several seconds, captain again signaled the first officer for re-entry. First officer again rotated the magnetic door lock control to unlock, but this time noted a 'lock fail' light illuminate. First officer had to unmask and unstrap, briefly leaving his flight station unattended to manually open the cockpit door for the captain to return to his station. Luckily the first officer did not have to leave the cockpit for his own 'relief' purposes, otherwise the situation might have repeated itself. After further review by maintenance, they found the striker solenoid stuck. The solenoid roller was degreased and door tested ok. MEL removed and aircraft ok for service. Callback conversation with reporter revealed the following information: the reporter believes the cockpit door needs an engineering review as everything that can go wrong will go wrong. Inadequate door knobs and as in this incident maintenance found the striker solenoid stuck. Striker was degreased and cleaned and operated ok. Safety is being compromised when the single crewman in the cockpit must remove the O2 mask and unstrap the harness and leave the seat to manually open the door. Callback conversation with reporter acn 639745 revealed the following information: the reporter stated the door was unlocked from the cockpit twice and on the second attempt the door failed electrically. Removed oxygen mask and seat belt. Left the seat and manually opened the door. This is a safety of flight problem and needs a positive fix. The reporter indicated that this was the second event of a cockpit door failure locking out crew members while in flight. The reporter reflected that the subject door always checks ok on the ground when required checks are performed.

Original NASA ASRS Text

Title: AN MD10-10 COCKPIT DOOR WOULD NOT UNLOCK NORMALLY TO ALLOW CAPT TO RETURN TO THE COCKPIT. FO UNMASKED AND UNSTRAPPED, THEN GOT OUT OF SEAT TO MANUALLY OPEN THE DOOR.

Narrative: CAPT LEFT THE FLT DECK FOR LAVATORY. UPON RETURN, SIGNALED THE FO WITH STANDARD 'CODE' COMBINATION FOR COCKPIT RE-ENTRY. FO PLACED THE MAGNETIC DOOR CTL SWITCH TO THE UN-LOCKED POSITION. GREEN 'ENTRY' LIGHT ILLUMINATED ON KEYPAD IN SUPERNUMERARY AREA, BUT CAPT WAS UNABLE TO OPEN THE DOOR. AFTER SEVERAL SECONDS, CAPT AGAIN SIGNALED THE FO FOR RE-ENTRY. FO AGAIN ROTATED THE MAGNETIC DOOR LOCK CTL TO UNLOCK, BUT THIS TIME NOTED A 'LOCK FAIL' LIGHT ILLUMINATE. FO HAD TO UNMASK AND UNSTRAP, BRIEFLY LEAVING HIS FLT STATION UNATTENDED TO MANUALLY OPEN THE COCKPIT DOOR FOR THE CAPT TO RETURN TO HIS STATION. LUCKILY THE FO DID NOT HAVE TO LEAVE THE COCKPIT FOR HIS OWN 'RELIEF' PURPOSES, OTHERWISE THE SIT MIGHT HAVE REPEATED ITSELF. AFTER FURTHER REVIEW BY MAINT, THEY FOUND THE STRIKER SOLENOID STUCK. THE SOLENOID ROLLER WAS DEGREASED AND DOOR TESTED OK. MEL REMOVED AND ACFT OK FOR SERVICE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR BELIEVES THE COCKPIT DOOR NEEDS AN ENGINEERING REVIEW AS EVERYTHING THAT CAN GO WRONG WILL GO WRONG. INADEQUATE DOOR KNOBS AND AS IN THIS INCIDENT MAINT FOUND THE STRIKER SOLENOID STUCK. STRIKER WAS DEGREASED AND CLEANED AND OPERATED OK. SAFETY IS BEING COMPROMISED WHEN THE SINGLE CREWMAN IN THE COCKPIT MUST REMOVE THE O2 MASK AND UNSTRAP THE HARNESS AND LEAVE THE SEAT TO MANUALLY OPEN THE DOOR. CALLBACK CONVERSATION WITH RPTR ACN 639745 REVEALED THE FOLLOWING INFO: THE RPTR STATED THE DOOR WAS UNLOCKED FROM THE COCKPIT TWICE AND ON THE SECOND ATTEMPT THE DOOR FAILED ELECTRICALLY. REMOVED OXYGEN MASK AND SEAT BELT. LEFT THE SEAT AND MANUALLY OPENED THE DOOR. THIS IS A SAFETY OF FLT PROB AND NEEDS A POSITIVE FIX. THE RPTR INDICATED THAT THIS WAS THE SECOND EVENT OF A COCKPIT DOOR FAILURE LOCKING OUT CREW MEMBERS WHILE IN FLT. THE RPTR REFLECTED THAT THE SUBJECT DOOR ALWAYS CHKS OK ON THE GND WHEN REQUIRED CHKS ARE PERFORMED.

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.

An MD10-10 cockpit door would not unlock normally to allow captain to return to the cockpit. First officer unmasked and unstrapped, then got out of seat to manually open the door.