Narrative:

While at rockford, il, preparing to takeoff for pontiac, mi, we noticed smoke coming from the right front nose just as we began taxiing onto the active for takeoff. We immediately shut down the engines, on the taxiway, and disembarked. Further inspection indicated that the heater had overheated due to the simultaneous failure of the combustion air pressure switch, the combustion air blower, and the ground fan to the heater. The combined failure caused the heater to continue heating to dangerous levels.

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Original NASA ASRS Text

Title: DURING TAXI PLT OF SMT NOTICED SMOKE COMING FROM NOSE OF ACFT. STOPPED AND DISEMBARKED FROM ACFT. ENGINES SHUT DOWN.

Narrative: WHILE AT ROCKFORD, IL, PREPARING TO TKOF FOR PONTIAC, MI, WE NOTICED SMOKE COMING FROM THE R FRONT NOSE JUST AS WE BEGAN TAXIING ONTO THE ACTIVE FOR TKOF. WE IMMEDIATELY SHUT DOWN THE ENGS, ON THE TXWY, AND DISEMBARKED. FURTHER INSPECTION INDICATED THAT THE HEATER HAD OVERHEATED DUE TO THE SIMULTANEOUS FAILURE OF THE COMBUSTION AIR PRESSURE SWITCH, THE COMBUSTION AIR BLOWER, AND THE GND FAN TO THE HEATER. THE COMBINED FAILURE CAUSED THE HEATER TO CONTINUE HEATING TO DANGEROUS LEVELS.

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.