Commuter aircraft has door warning light illuminate. Rapid descent, altitude deviation.

Attributes
ACN	162885
Time
Date	199011
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : loz
State Reference	KY
Altitude	msl bound lower : 12700 msl bound upper : 13000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : sna
Operator	common carrier : air carrier
Make Model Name	Light Transport, Low Wing, 2 Turboprop Eng
Flight Phase	climbout : intermediate altitude descent other
Route In Use	enroute : on vectors enroute airway : zid
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 : 200 flight time total : 5000 flight time type : 1500
ASRS Report	162885
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 250 flight time total : 2700 flight time type : 1200
ASRS Report	162796
Events
Anomaly	aircraft equipment problem : critical altitude deviation : overshoot non adherence : far non adherence : clearance
Independent Detector	other controllera other flight crewa
Resolutory Action	controller : issued new clearance flight crew : returned to intended course or assigned course
Consequence	faa : reviewed incident with flight crew
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

We were climbing to 16000' through 15500' when door warning light came on. I was flying and immediately started a descent per procedure. First officer told atl center we were descending to 8000'. Atlanta handed us off to ZID. On contact to ZID we told him we were descending to 8000' for a pressurization problem (procedure for door light is to descend to minimum safe altitude. Reduce cabin pressure). We were established on the arwy and center turned us 30 degree right for traffic. Through approximately 13500', center told us to maintain 13000', again for traffic. We asked him if we could give him good rate rb through 13000' (we were descending in excess of 2000 FPM) to 8000'. His reply was negative, maintain 13000' for traffic. By the time the captain started to arrest the descent, altitude was 12900', and after a smooth pull up, our descent was stopped at 12700' and we started an immediate climb back to 13000'. Center asked our altitude, we told him 13000' as we climbed back to 13000'. (Our time below 13000' was probably less than 30 seconds). A couple of mins later, we were cleared down to 8000', where we continued our flight. Prior to handoff, the controller told us of an investigation into a possible altitude deviation and gave us a phone number for further information.

Original NASA ASRS Text

Title: COMMUTER ACFT HAS DOOR WARNING LIGHT ILLUMINATE. RAPID DESCENT, ALT DEVIATION.

Narrative: WE WERE CLBING TO 16000' THROUGH 15500' WHEN DOOR WARNING LIGHT CAME ON. I WAS FLYING AND IMMEDIATELY STARTED A DSNT PER PROC. F/O TOLD ATL CTR WE WERE DSNDING TO 8000'. ATLANTA HANDED US OFF TO ZID. ON CONTACT TO ZID WE TOLD HIM WE WERE DSNDING TO 8000' FOR A PRESSURIZATION PROB (PROC FOR DOOR LIGHT IS TO DSND TO MINIMUM SAFE ALT. REDUCE CABIN PRESSURE). WE WERE ESTABLISHED ON THE ARWY AND CTR TURNED US 30 DEG R FOR TFC. THROUGH APPROX 13500', CTR TOLD US TO MAINTAIN 13000', AGAIN FOR TFC. WE ASKED HIM IF WE COULD GIVE HIM GOOD RATE RB THROUGH 13000' (WE WERE DSNDING IN EXCESS OF 2000 FPM) TO 8000'. HIS REPLY WAS NEGATIVE, MAINTAIN 13000' FOR TFC. BY THE TIME THE CAPT STARTED TO ARREST THE DSNT, ALT WAS 12900', AND AFTER A SMOOTH PULL UP, OUR DSNT WAS STOPPED AT 12700' AND WE STARTED AN IMMEDIATE CLB BACK TO 13000'. CTR ASKED OUR ALT, WE TOLD HIM 13000' AS WE CLBED BACK TO 13000'. (OUR TIME BELOW 13000' WAS PROBABLY LESS THAN 30 SECS). A COUPLE OF MINS LATER, WE WERE CLRED DOWN TO 8000', WHERE WE CONTINUED OUR FLT. PRIOR TO HDOF, THE CTLR TOLD US OF AN INVESTIGATION INTO A POSSIBLE ALT DEV AND GAVE US A PHONE NUMBER FOR FURTHER INFO.

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.