Narrative:

Arrived at aircraft about 40 min prior to scheduled out time. Noticed first officer (first officer) seated in flight deck with APU running. Went aft to stow my crew bag and noticed no air conditioning / stuffy cabin. Stowed my flight bag and sat down in the captain (ca) seat and noted that the pack switchlights were out; selected environmental control system (ecs) page and noted the packs were not on and then noted that the leng start switchlight was on!!! Immediately noted leng N2 around 35% and immediately noted both thrust levers were in the shutoff detent. Immediately selected leng ignition off switchlight and the start switchlight went out. And the packs came on (just like they're supposed to do!!!). Talked to first officer and he said he must have accidently pressed the leng start switchlight when he arrived and started up the APU.so to summarize the above: when the first officer arrived at the aircraft he started the APU and inadvertently activated the leng start switchlight. The left engine began to motor since the APU was running. The pack valves remained closed; which was why I noticed a 'stuffy' cabin when I went aft to stow my crew bag. I would estimate that the engine had been motoring (but not started) for about 10 minutes; obviously exceeding by a country mile the engine starter start and dry motoring limitations!!! And by the way; he apparently preflighted the aircraft while the engine was dry motoring. But it was a very windy day and the other engine was motoring with the wind and it was noisy with aircraft turning nearby.I called maintenance and advised them of the obvious exceedance of starter limitations. After consulting with the line maintenance technician it was decided to start the engine at the gate which I did. About 20 minutes had elapsed at this point since I had selected the leng stop switchlight. The leng started normally. I was advised that [a logbook] discrepancy was not necessary. The flight departed on time and proceeded uneventfully to destination.the next day we had the same airplane for 3 legs and the leng started and operated normally the entire time.

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Original NASA ASRS Text

Title: CRJ-900 flight crew member inadvertently motored one engine turbojet was parked at the gate.

Narrative: Arrived at aircraft about 40 min prior to scheduled out time. Noticed First Officer (FO) seated in flight deck with APU running. Went aft to stow my crew bag and noticed no air conditioning / stuffy cabin. Stowed my flight bag and sat down in the Captain (CA) seat and noted that the PACK switchlights were out; selected Environmental Control System (ECS) page and noted the PACKS were not ON and then noted that the LENG START switchlight was ON!!! Immediately noted LENG N2 around 35% and immediately noted BOTH Thrust Levers were in the Shutoff detent. Immediately selected LENG Ignition OFF switchlight and the START switchlight went out. And the PACKS came ON (just like they're supposed to do!!!). Talked to FO and he said he must have accidently pressed the LENG START switchlight when he arrived and started up the APU.So to summarize the above: When the FO arrived at the aircraft he started the APU and inadvertently activated the LENG START switchlight. The left engine began to motor since the APU was running. The PACK valves remained closed; which was why I noticed a 'stuffy' cabin when I went aft to stow my crew bag. I would estimate that the engine had been motoring (but not started) for about 10 minutes; obviously exceeding by a country mile the engine starter start and dry motoring limitations!!! And by the way; he apparently preflighted the aircraft while the engine was dry motoring. But it was a very windy day and the other engine was motoring with the wind and it was noisy with aircraft turning nearby.I called maintenance and advised them of the obvious exceedance of starter limitations. After consulting with the line maintenance technician it was decided to start the engine at the gate which I did. About 20 minutes had elapsed at this point since I had selected the LENG STOP switchlight. The LENG started normally. I was advised that [a logbook] discrepancy was not necessary. The flight departed on time and proceeded uneventfully to destination.The next day we had the same airplane for 3 legs and the LENG started and operated normally the entire time.

Data retrieved from NASA's ASRS site 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.