A false cargo door warning required the aircraft to return land.

Attributes
ACN	287721
Time
Date	199411
Day	Mon
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : sjc
State Reference	CA
Altitude	agl bound lower : 0 agl bound upper : 5000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tower : sjc
Operator	common carrier : air carrier
Make Model Name	MD-82
Operating Under FAR Part	Part 121
Flight Phase	climbout : initial climbout : takeoff other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 40 flight time total : 10500 flight time type : 4000
ASRS Report	287721
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	none taken : unable other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

There are recurring incidents of false 'door open' warning lights on our MD82-MD83's. This is apparently due to door misalignment or shifting of the door during turbulence or jarring on rough runways like san jose, ca. During rotation and liftoff, we received an aft cargo door open annunciation light. The cabin altitude was increasing. Due to concerns of pressurization capability,we decided to return to land. The subsequent landing was normal. Inspection by ramp personnel (not mechanics) showed the door to be closed. The door open annunciator system appeared to be working properly (each cargo door was opened and closed repeatedly). My decision was that no maintenance was required. Therefore no maintenance log entry was made. After refueling, the flight continued normally with no further door open warning lights. It seems that a different design for door open indication sensing is necessary to prevent this recurring scenario from happening. This is my 4TH experience in 4000 hours with this same problem. Many others have occurred to other pilots in our company alone. Probably an industry-wide problem. Callback conversation with reporter revealed the following information: the reporter is an instructor pilot with an air carrier that operates a medium sized fleet of md-80 aircraft. This analyst is retired from a major air carrier that operates an extremely large fleet of md-80 aircraft. The reporter and the analyst talked about this problem and the fact that the analyst has never heard of this problem before, either within his former air carrier or any other air carrier. The conclusion is that maybe the reporter's air carrier has a unique problem. The reporter was instrumental in getting a new procedure on his air carrier's checklist for this problem. The sensing device is a 'proximity switch.' the solution for the ground personnel is to slam the cargo doors harder, which of course is no solution at all. The reporter was counseled to have his people contact the very large operator of md-80 aircraft and see if they have found a solution to this problem.

Original NASA ASRS Text

Title: A FALSE CARGO DOOR WARNING REQUIRED THE ACFT TO RETURN LAND.

Narrative: THERE ARE RECURRING INCIDENTS OF FALSE 'DOOR OPEN' WARNING LIGHTS ON OUR MD82-MD83'S. THIS IS APPARENTLY DUE TO DOOR MISALIGNMENT OR SHIFTING OF THE DOOR DURING TURB OR JARRING ON ROUGH RWYS LIKE SAN JOSE, CA. DURING ROTATION AND LIFTOFF, WE RECEIVED AN AFT CARGO DOOR OPEN ANNUNCIATION LIGHT. THE CABIN ALT WAS INCREASING. DUE TO CONCERNS OF PRESSURIZATION CAPABILITY,WE DECIDED TO RETURN TO LAND. THE SUBSEQUENT LNDG WAS NORMAL. INSPECTION BY RAMP PERSONNEL (NOT MECHS) SHOWED THE DOOR TO BE CLOSED. THE DOOR OPEN ANNUNCIATOR SYS APPEARED TO BE WORKING PROPERLY (EACH CARGO DOOR WAS OPENED AND CLOSED REPEATEDLY). MY DECISION WAS THAT NO MAINT WAS REQUIRED. THEREFORE NO MAINT LOG ENTRY WAS MADE. AFTER REFUELING, THE FLT CONTINUED NORMALLY WITH NO FURTHER DOOR OPEN WARNING LIGHTS. IT SEEMS THAT A DIFFERENT DESIGN FOR DOOR OPEN INDICATION SENSING IS NECESSARY TO PREVENT THIS RECURRING SCENARIO FROM HAPPENING. THIS IS MY 4TH EXPERIENCE IN 4000 HRS WITH THIS SAME PROB. MANY OTHERS HAVE OCCURRED TO OTHER PLTS IN OUR COMPANY ALONE. PROBABLY AN INDUSTRY-WIDE PROB. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR IS AN INSTRUCTOR PLT WITH AN ACR THAT OPERATES A MEDIUM SIZED FLEET OF MD-80 ACFT. THIS ANALYST IS RETIRED FROM A MAJOR ACR THAT OPERATES AN EXTREMELY LARGE FLEET OF MD-80 ACFT. THE RPTR AND THE ANALYST TALKED ABOUT THIS PROB AND THE FACT THAT THE ANALYST HAS NEVER HEARD OF THIS PROB BEFORE, EITHER WITHIN HIS FORMER ACR OR ANY OTHER ACR. THE CONCLUSION IS THAT MAYBE THE RPTR'S ACR HAS A UNIQUE PROB. THE RPTR WAS INSTRUMENTAL IN GETTING A NEW PROC ON HIS ACR'S CHKLIST FOR THIS PROB. THE SENSING DEVICE IS A 'PROX SWITCH.' THE SOLUTION FOR THE GND PERSONNEL IS TO SLAM THE CARGO DOORS HARDER, WHICH OF COURSE IS NO SOLUTION AT ALL. THE RPTR WAS COUNSELED TO HAVE HIS PEOPLE CONTACT THE VERY LARGE OPERATOR OF MD-80 ACFT AND SEE IF THEY HAVE FOUND A SOLUTION TO THIS PROB.

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.