Ce-560XL flight crew reported shortly after takeoff they had acm O'heat and bld air O'heat messages;...

Attributes
ACN	1025254
Time
Date	201207
Local Time Of Day	0601-1200
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Citation Excel (C560XL)
Operating Under FAR Part	Part 91
Flight Phase	Takeoff
Component
Aircraft Component	Air Conditioning and Pressurization Pack
Person 1
Function	First Officer Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Person 2
Function	Pilot Flying Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Critical Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor

Narrative:

[Shortly after] takeoff at about 300 ft AGL the acm O'heat came on followed by the left bld air O'heat. There was black acrid smoke in the cockpit and the cabin. Due to the fact we were in a critical phase of flight and at low altitude; we turned the pressure source to off and declared an emergency. We entered the downwind and configured for landing. The captain briefed the passengers over the intercom. When we were abeam the numbers the smoke started to lessen. After landing we cleared at the first available taxi way; performed an emergency shut down. While the captain performed the shutdown the first officer evacuated the passengers. We gathered about 100 ft in front of the aircraft and let the fire department check the plane. There was no fire detected.

Original NASA ASRS Text

Title: CE-560XL flight crew reported shortly after takeoff they had ACM O'HEAT and BLD AIR O'HEAT messages; as well as black smoke in the cockpit and cabin. They declared an emergency; returned to departure airport; and evacuated the aircraft.

Narrative: [Shortly after] takeoff at about 300 FT AGL the ACM O'HEAT came on followed by the left BLD AIR O'HEAT. There was black acrid smoke in the cockpit and the cabin. Due to the fact we were in a critical phase of flight and at low altitude; we turned the pressure source to OFF and declared an emergency. We entered the downwind and configured for landing. The Captain briefed the passengers over the intercom. When we were abeam the numbers the smoke started to lessen. After landing we cleared at the first available taxi way; performed an emergency shut down. While the Captain performed the shutdown the First Officer evacuated the passengers. We gathered about 100 FT in front of the aircraft and let the Fire Department check the plane. There was no fire detected.

Data retrieved from NASA's ASRS site as of July 2013 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.

Ce-560XL flight crew reported shortly after takeoff they had acm O'heat and bld air O'heat messages; as well as black smoke in the cockpit and cabin. They declared an emergency; returned to departure airport; and evacuated the aircraft.