Narrative:

I was troubleshooting the roll spoiler circuit breaker popping on aircraft X. I got avionics to change out diode CR4 for the lift dump valve in the #1 nacelle. To double check the wiring, panel 261 dt was lifted for access to the wing root cannon plug. While avionics was checking CR4. I moved to the r-hand wing root cannon plug under panel 261 nt to check the wire (M) on 2700-2P. I found a short. Around that time, avionics was done in 261 dt. I was there when the cannon plug was installed. Avionics grabbed panel 261 dt and put it in place. I turned back to the r-hand wing root and the shorted wire (I assumed they put the panel down). When the temporary wire was installed, I ty-wrapped the wire bundles in the wing root and did an area safety check and closed panel 261 nt. When I was finished I looked over at 261 dt and did not see any cam locks sticking up, so I thought it was down and installed. Since both panels were on the same job card, I signed it off since I was there and locked. I should have verbally acknowledged the panel with avionics. The second flight crew noticed panel 261 dt was not installed.

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Original NASA ASRS Text

Title: A DEHAVILLAND DASH 8 WAS DISPATCHED IN NON COMPLIANCE WITH AN UPPER WING ROOT PANEL NOT SECURED. PANEL DEPARTED THE ACFT.

Narrative: I WAS TROUBLESHOOTING THE ROLL SPOILER CIRCUIT BREAKER POPPING ON ACFT X. I GOT AVIONICS TO CHANGE OUT DIODE CR4 FOR THE LIFT DUMP VALVE IN THE #1 NACELLE. TO DOUBLE CHK THE WIRING, PANEL 261 DT WAS LIFTED FOR ACCESS TO THE WING ROOT CANNON PLUG. WHILE AVIONICS WAS CHKING CR4. I MOVED TO THE R-HAND WING ROOT CANNON PLUG UNDER PANEL 261 NT TO CHK THE WIRE (M) ON 2700-2P. I FOUND A SHORT. AROUND THAT TIME, AVIONICS WAS DONE IN 261 DT. I WAS THERE WHEN THE CANNON PLUG WAS INSTALLED. AVIONICS GRABBED PANEL 261 DT AND PUT IT IN PLACE. I TURNED BACK TO THE R-HAND WING ROOT AND THE SHORTED WIRE (I ASSUMED THEY PUT THE PANEL DOWN). WHEN THE TEMPORARY WIRE WAS INSTALLED, I TY-WRAPPED THE WIRE BUNDLES IN THE WING ROOT AND DID AN AREA SAFETY CHK AND CLOSED PANEL 261 NT. WHEN I WAS FINISHED I LOOKED OVER AT 261 DT AND DID NOT SEE ANY CAM LOCKS STICKING UP, SO I THOUGHT IT WAS DOWN AND INSTALLED. SINCE BOTH PANELS WERE ON THE SAME JOB CARD, I SIGNED IT OFF SINCE I WAS THERE AND LOCKED. I SHOULD HAVE VERBALLY ACKNOWLEDGED THE PANEL WITH AVIONICS. THE SECOND FLT CREW NOTICED PANEL 261 DT WAS NOT INSTALLED.

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.