Light transport cabin door light comes on in flight. Return and land.

Attributes
ACN	293833
Time
Date	199501
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : dxo airport : dtw
State Reference	MI
Altitude	msl bound lower : 8000 msl bound upper : 8000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : dtw
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 135
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 180 flight time total : 4100 flight time type : 2500
ASRS Report	293833
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : declared emergency flight crew : overcame equipment problem other
Consequence	Other
Supplementary
Primary Problem	Aircraft

Narrative:

Approximately 25 mi east of detroit, we observed the cabin door warning light illuminate. We complied with the QRH emergency evacuation ditching and doors checklist which called for us to depressurize the cabin. At this time we were at 8000 ft with a differential pressure of 3.5. We depressurized the aircraft and requested a descent to 5000 ft. We advised our company dispatch of the problem and our intent to return to detroit. They agreed so, we advised ATC that we'd like to return.as the cabin differential neared zero, the door light extinguished. We observed no other abnormalities and landed without incident. As the captain, I felt we did the best thing in the interest of safety by returning to detroit. We completed all emergency funcitons related to this incident, and conferred with our company dispatch which agreed with us.

Original NASA ASRS Text

Title: LTT CABIN DOOR LIGHT COMES ON IN FLT. RETURN AND LAND.

Narrative: APPROX 25 MI E OF DETROIT, WE OBSERVED THE CABIN DOOR WARNING LIGHT ILLUMINATE. WE COMPLIED WITH THE QRH EMER EVACUATION DITCHING AND DOORS CHKLIST WHICH CALLED FOR US TO DEPRESSURIZE THE CABIN. AT THIS TIME WE WERE AT 8000 FT WITH A DIFFERENTIAL PRESSURE OF 3.5. WE DEPRESSURIZED THE ACFT AND REQUESTED A DSCNT TO 5000 FT. WE ADVISED OUR COMPANY DISPATCH OF THE PROB AND OUR INTENT TO RETURN TO DETROIT. THEY AGREED SO, WE ADVISED ATC THAT WE'D LIKE TO RETURN.AS THE CABIN DIFFERENTIAL NEARED ZERO, THE DOOR LIGHT EXTINGUISHED. WE OBSERVED NO OTHER ABNORMALITIES AND LANDED WITHOUT INCIDENT. AS THE CAPT, I FELT WE DID THE BEST THING IN THE INTEREST OF SAFETY BY RETURNING TO DETROIT. WE COMPLETED ALL EMER FUNCITONS RELATED TO THIS INCIDENT, AND CONFERRED WITH OUR COMPANY DISPATCH WHICH AGREED WITH US.

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.