Narrative:

After takeoff both packs ran away hot and filled cabin with very hot air. Unable to control temperature in automatic or manual. Turned packs off and set up for return to ord. Had some ATC frequency problems and declared emergency for priority handling by approach. Normal approach and landing.

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Original NASA ASRS Text

Title: AN FK100 FLT CREW RETURNS/LANDS WHEN THEIR TWO PACKS RUN AMUCK AND OVERHEAT THE ACFT ON DEP FROM ORD, IL.

Narrative: AFTER TKOF BOTH PACKS RAN AWAY HOT AND FILLED CABIN WITH VERY HOT AIR. UNABLE TO CTL TEMP IN AUTO OR MANUAL. TURNED PACKS OFF AND SET UP FOR RETURN TO ORD. HAD SOME ATC FREQ PROBS AND DECLARED EMER FOR PRIORITY HANDLING BY APCH. NORMAL APCH AND LNDG.

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.