Narrative:

Called ground control for taxi instructions after engine start and received the clearance to taxi to runway 30L via G2; G and runway 4. We were not told to give way to or follow any other aircraft. Leaving the ramp and starting to enter taxiway G from G2 I looked left and saw a small red and silver single engine low wing aircraft taxiing at a high speed just in front and left of our nose. I braked firmly to avoid the aircraft. Not sure what type it was but my first officer believed it was a cirrus. We reported this to ground control. No one onboard was injured. We took off and proceeded to [destination] with no other incident.

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Original NASA ASRS Text

Title: MD-82 flight crew reported that during taxi out at SAT they had to brake 'firmly' to avoid a collision with a light aircraft.

Narrative: Called Ground Control for taxi instructions after engine start and received the clearance to taxi to runway 30L via G2; G and runway 4. We were not told to give way to or follow any other aircraft. Leaving the ramp and starting to enter taxiway G from G2 I looked left and saw a small red and silver single engine low wing aircraft taxiing at a high speed just in front and left of our nose. I braked firmly to avoid the aircraft. Not sure what type it was but my FO believed it was a Cirrus. We reported this to ground control. No one onboard was injured. We took off and proceeded to [destination] with no other incident.

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.