Narrative:

After start up; all system checks were normal. We began our taxi to runway xxr for takeoff and were holding short of runway xy when tower told us it would be at least a 15 minute delay to take off unless we could takeoff runway xz. We accepted runway xz and taxied onto runway xy then made an immediate right onto taxiway foxtrot and then a left onto taxiway a. We were cleared to cross both runway xxr/left. At about 200 feet from the hold short line of runway xz; we both looked at each other and asked if we smelled a musky smell in the airplane. At that time we looked back in the cabin and realized it was filling up with smoke. I came to a stop at the hold short line of runway xz and my co-pilot called for the truck to start rolling and I [advised ATC] after asking if we were declaring an emergency. I immediately shut off the left engine and my co-pilot opened the door and ran to the back of the airplane to look in the back to make sure there was no smoke coming out anywhere. He then came back into the airplane and said he didn't spot anything and began evacuating the passengers from the airplane as I continued to shut the airplane down. I notified tower I was going off com and exited the plane. The fire department showed up and could not find anything wrong and left. We then had the airplane towed to the FBO where it sits for maintenance to look at it.

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Original NASA ASRS Text

Title: Lear 60 flight crew reported evacuating the aircraft on the taxiway due to smoke in the cabin.

Narrative: After start up; all system checks were normal. We began our taxi to Runway XXR for takeoff and were holding short of Runway XY when Tower told us it would be at least a 15 minute delay to take off unless we could takeoff Runway XZ. We accepted Runway XZ and taxied onto Runway XY then made an immediate right onto Taxiway Foxtrot and then a left onto Taxiway A. We were cleared to cross both Runway XXR/L. At about 200 feet from the hold short line of Runway XZ; we both looked at each other and asked if we smelled a musky smell in the airplane. At that time we looked back in the cabin and realized it was filling up with smoke. I came to a stop at the hold short line of Runway XZ and my co-pilot called for the truck to start rolling and I [advised ATC] after asking if we were declaring an emergency. I immediately shut off the left engine and my co-pilot opened the door and ran to the back of the airplane to look in the back to make sure there was no smoke coming out anywhere. He then came back into the airplane and said he didn't spot anything and began evacuating the passengers from the airplane as I continued to shut the airplane down. I notified Tower I was going off com and exited the plane. The fire department showed up and could not find anything wrong and left. We then had the airplane towed to the FBO where it sits for maintenance to look at it.

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.