Narrative:

During initial climb the acm O'heat light illuminated; smoke with light haze and order was observed in cockpit and cabin. Completed abnormal checklist for acm O'heat and declared emergency. Completed all applicable checklist for landing and returned to [departure airport]. Acm O'heat light extinguished and smoke dissipated prior to landing.

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Original NASA ASRS Text

Title: CE-560XL flight crew reported ACM Overheat light illuminated on climb out; accompanied by smoke and odor. Flight declared an emergency and returned to departure airport.

Narrative: During initial climb the ACM O'Heat Light illuminated; smoke with light haze and order was observed in cockpit and cabin. Completed abnormal checklist for ACM O'Heat and declared emergency. Completed all applicable checklist for landing and returned to [departure airport]. ACM O'Heat light extinguished and smoke dissipated prior to landing.

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.