C172 instructor has loss of engine power and makes an off field landing.

Attributes
ACN	716499
Time
Date	200611
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : bum.vortac
State Reference	MO
Altitude	msl single value : 2500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : instructional
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	cruise : level
Flight Plan	None
Person 1
Affiliation	other
Function	instruction : instructor
Qualification	pilot : commercial pilot : cfi pilot : instrument pilot : multi engine
Experience	flight time last 90 days : 130 flight time total : 1000 flight time type : 150
ASRS Report	716499
Person 2
Affiliation	other
Function	instruction : trainee
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa other flight crewb
Resolutory Action	flight crew : landed in emergency condition
Consequence	other
Factors
Maintenance	performance deficiency : inspection performance deficiency : scheduled maintenance
Supplementary
Problem Areas	Aircraft Flight Crew Human Performance Maintenance Human Performance
Primary Problem	Maintenance Human Performance

Narrative:

The C172 aircraft I was instructing in; suffered a loss of engine power while in cruise flight. I assumed control of the aircraft; attempted to reestablish engine power with the appropriate checklist. Adjusting the throttle yielded no change in engine power. Due to an overcast layer at 3000 ft MSL; we were flying at 2500 ft MSL (approximately 1500 ft AGL). With the aircraft operating at idle power only I had no choice but to initiate an off-airport landing. I made a 'mayday' call on 121.5 and squawked 7700. I was able to select a smooth dry field oriented into the wind and made an uneventful landing in a wheat field. The aircraft came to rest undamaged and neither I nor my student were injured. I contacted a commercial airliner on 121.5 when the aircraft had come to stop and requested that he relay to ZKC that the aircraft was undamaged and the occupants uninjured. My student made a follow-up phone call with columbia FSS informing them of our status. My student and I de-cowled the aircraft shortly after landing and we were able to determine that the throttle cable had become disconnected from the carburetor. The aircraft was able to maintain 'idle' power only and no input from the pilot in the cockpit could have restored engine power. The aircraft had recently undergone an annual inspection. This was the aircraft's second flight following its annual inspection. The aircraft owner informed me that the throttle cable and attachment assembly had been replaced during the annual inspection.

Original NASA ASRS Text

Title: C172 INSTRUCTOR HAS LOSS OF ENG PWR AND MAKES AN OFF FIELD LNDG.

Narrative: THE C172 ACFT I WAS INSTRUCTING IN; SUFFERED A LOSS OF ENG PWR WHILE IN CRUISE FLT. I ASSUMED CTL OF THE ACFT; ATTEMPTED TO REESTABLISH ENG PWR WITH THE APPROPRIATE CHKLIST. ADJUSTING THE THROTTLE YIELDED NO CHANGE IN ENG PWR. DUE TO AN OVCST LAYER AT 3000 FT MSL; WE WERE FLYING AT 2500 FT MSL (APPROX 1500 FT AGL). WITH THE ACFT OPERATING AT IDLE PWR ONLY I HAD NO CHOICE BUT TO INITIATE AN OFF-ARPT LNDG. I MADE A 'MAYDAY' CALL ON 121.5 AND SQUAWKED 7700. I WAS ABLE TO SELECT A SMOOTH DRY FIELD ORIENTED INTO THE WIND AND MADE AN UNEVENTFUL LNDG IN A WHEAT FIELD. THE ACFT CAME TO REST UNDAMAGED AND NEITHER I NOR MY STUDENT WERE INJURED. I CONTACTED A COMMERCIAL AIRLINER ON 121.5 WHEN THE ACFT HAD COME TO STOP AND REQUESTED THAT HE RELAY TO ZKC THAT THE ACFT WAS UNDAMAGED AND THE OCCUPANTS UNINJURED. MY STUDENT MADE A FOLLOW-UP PHONE CALL WITH COLUMBIA FSS INFORMING THEM OF OUR STATUS. MY STUDENT AND I DE-COWLED THE ACFT SHORTLY AFTER LNDG AND WE WERE ABLE TO DETERMINE THAT THE THROTTLE CABLE HAD BECOME DISCONNECTED FROM THE CARB. THE ACFT WAS ABLE TO MAINTAIN 'IDLE' PWR ONLY AND NO INPUT FROM THE PLT IN THE COCKPIT COULD HAVE RESTORED ENG PWR. THE ACFT HAD RECENTLY UNDERGONE AN ANNUAL INSPECTION. THIS WAS THE ACFT'S SECOND FLT FOLLOWING ITS ANNUAL INSPECTION. THE ACFT OWNER INFORMED ME THAT THE THROTTLE CABLE AND ATTACHMENT ASSEMBLY HAD BEEN REPLACED DURING THE ANNUAL INSPECTION.

Data retrieved from NASA's ASRS site as of January 2009 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.