Narrative:

During takeoff the engines were brought to high idle abruptly. The rapid increase in fuel flow and high ambient temperatures (110 degree F+) resulted in momentary egt indications of approximately 30 degree C over maximum for that RPM. I didn't recognize the overtemp condition because the change to high idle normally is not temperature critical and the egt observed is very common during engine start. In short I failed to correlate the egt limitation with the RPM. The biggest problem is that the aircraft continued in service for 2 days until I realized my mistake and reported it to the company. My recommendation, aside from vigilance, is for the aircraft and engine manufacturers to revise their operating manuals with a warning about this potential for overtemp.

Related reports:

Google
 

Original NASA ASRS Text

Title: COMMUTER SMT OVER MAXIMUM EGT WAS NOT REPORTED FOR 2 DAYS. SITUATION OCCURRED WHEN ENGINES WERE BROUGHT TO HIGH IDLE AT THE START OF TKOF. HIGH AMBIENT GND TEMPERATURE WAS A FACTOR.

Narrative: DURING TKOF THE ENGINES WERE BROUGHT TO HIGH IDLE ABRUPTLY. THE RAPID INCREASE IN FUEL FLOW AND HIGH AMBIENT TEMPS (110 DEG F+) RESULTED IN MOMENTARY EGT INDICATIONS OF APPROX 30 DEG C OVER MAX FOR THAT RPM. I DIDN'T RECOGNIZE THE OVERTEMP CONDITION BECAUSE THE CHANGE TO HIGH IDLE NORMALLY IS NOT TEMP CRITICAL AND THE EGT OBSERVED IS VERY COMMON DURING ENGINE START. IN SHORT I FAILED TO CORRELATE THE EGT LIMITATION WITH THE RPM. THE BIGGEST PROBLEM IS THAT THE ACFT CONTINUED IN SERVICE FOR 2 DAYS UNTIL I REALIZED MY MISTAKE AND REPORTED IT TO THE COMPANY. MY RECOMMENDATION, ASIDE FROM VIGILANCE, IS FOR THE ACFT AND ENGINE MANUFACTURERS TO REVISE THEIR OPERATING MANUALS WITH A WARNING ABOUT THIS POTENTIAL FOR OVERTEMP.

Data retrieved from NASA's ASRS site as of August 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.