Just after takeoff, engine of small aircraft lost power. Pilot returned and landed.

Attributes
ACN	123555
Time
Date	198909
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : bur
State Reference	CA
Altitude	msl bound lower : 0 msl bound upper : 500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : bur
Operator	general aviation : instructional
Make Model Name	Small Aircraft, Low Wing, 1 Eng, Retractable Gear
Flight Phase	climbout : takeoff landing other
Flight Plan	None
Person 1
Affiliation	Other
Function	flight crew : single pilot
Qualification	pilot : instrument pilot : commercial
Experience	flight time last 90 days : 36 flight time total : 1000 flight time type : 100
ASRS Report	123555
Person 2
Affiliation	government : faa
Function	controller : local
Qualification	controller : non radar
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	other other : unspecified cockpit
Resolutory Action	flight crew : declared emergency none taken : anomaly accepted
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

Just after takeoff from bur runway 07, power dropped to about 5% at approximately 500' AGL. Was able to make descending 270 degree turn and land on runway 15. Received tower clearance to land. Landing uneventful. Mechanic found alternate air door had broken off at hinges and lodged in engine air intake channel to injection box, cutting off air supply to engine.

Original NASA ASRS Text

Title: JUST AFTER TKOF, ENGINE OF SMA LOST POWER. PLT RETURNED AND LANDED.

Narrative: JUST AFTER TKOF FROM BUR RWY 07, PWR DROPPED TO ABOUT 5% AT APPROX 500' AGL. WAS ABLE TO MAKE DSNDING 270 DEG TURN AND LAND ON RWY 15. RECEIVED TWR CLRNC TO LAND. LNDG UNEVENTFUL. MECH FOUND ALTERNATE AIR DOOR HAD BROKEN OFF AT HINGES AND LODGED IN ENG AIR INTAKE CHANNEL TO INJECTION BOX, CUTTING OFF AIR SUPPLY TO ENG.

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.