Narrative:

While pushing back at smf; got clearance to start both engines. Started #1 engine; set brakes; and told ground crew to disconnect headset. Saw another ramp person on tug driving towards the right side of aircraft while we were starting #2 engine. I assumed he was going around the right wing for some reason; maybe to clear wing on taxi out. About 1/2 way through #2 engine start; forward cargo door and master caution illuminated for about 1-2 seconds. First officer and I looked at each other curiously; and I thought it was an anomaly or intermittent loose door handle; but then we saw ramp person driving away from aircraft. I was told by a ramp supervisor when I called back later in the day that he loaded a bag while we were starting the #2 engine; much to our disbelief. The door light went on and off so fast that we didn't shut down engine; due to our belief that it was a brief anomaly.

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Original NASA ASRS Text

Title: B737 FLT CREW REPORTS GROUND CREW LOADING LATE BAG IN CARGO HOLD DURING #2 ENGINE START.

Narrative: WHILE PUSHING BACK AT SMF; GOT CLRNC TO START BOTH ENGS. STARTED #1 ENG; SET BRAKES; AND TOLD GND CREW TO DISCONNECT HEADSET. SAW ANOTHER RAMP PERSON ON TUG DRIVING TOWARDS THE R SIDE OF ACFT WHILE WE WERE STARTING #2 ENG. I ASSUMED HE WAS GOING AROUND THE R WING FOR SOME REASON; MAYBE TO CLR WING ON TAXI OUT. ABOUT 1/2 WAY THROUGH #2 ENG START; FORWARD CARGO DOOR AND MASTER CAUTION ILLUMINATED FOR ABOUT 1-2 SECONDS. FO AND I LOOKED AT EACH OTHER CURIOUSLY; AND I THOUGHT IT WAS AN ANOMALY OR INTERMITTENT LOOSE DOOR HANDLE; BUT THEN WE SAW RAMP PERSON DRIVING AWAY FROM ACFT. I WAS TOLD BY A RAMP SUPVR WHEN I CALLED BACK LATER IN THE DAY THAT HE LOADED A BAG WHILE WE WERE STARTING THE #2 ENG; MUCH TO OUR DISBELIEF. THE DOOR LIGHT WENT ON AND OFF SO FAST THAT WE DIDN'T SHUT DOWN ENG; DUE TO OUR BELIEF THAT IT WAS A BRIEF ANOMALY.

Data retrieved from NASA's ASRS site as of January 2009 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.