A C172 pilot experienced an unexplained 80% RPM loss. An emergency highway landing followed with no ...

Attributes
ACN	651468
Time
Date	200505
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	agl single value : 0
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	general aviation : personal
Make Model Name	Skyhawk 172/Cutlass 172
Operating Under FAR Part	Part 91
Flight Phase	cruise : level landing : roll ground : maintenance
Flight Plan	None
Person 1
Affiliation	other
Function	flight crew : single pilot
Qualification	pilot : private
Experience	flight time last 90 days : 7 flight time total : 759 flight time type : 65
ASRS Report	651468
Events
Anomaly	aircraft equipment problem : critical other anomaly other
Independent Detector	other flight crewa
Resolutory Action	flight crew : landed in emergency condition
Consequence	other
Supplementary
Problem Areas	Aircraft
Primary Problem	Aircraft

Narrative:

Departed ZZZ at XA15 planning a 25 mi roundtrip to highway; circle and return to ZZZ. At around XA27; I experienced an 80% RPM loss about 1 mi north of highway at an altitude of +2500 ft MSL. At XA30 I made an emergency landing on highway approximately 9 mi west of abc. The aircraft did not sustain any damage nor was anyone endangered or hurt. The cause of RPM loss has not yet been determined. The wings were removed and the aircraft was trucked back to ZZZ.

Original NASA ASRS Text

Title: A C172 PLT EXPERIENCED AN UNEXPLAINED 80% RPM LOSS. AN EMER HWY LNDG FOLLOWED WITH NO DAMAGE OR INJURIES.

Narrative: DEPARTED ZZZ AT XA15 PLANNING A 25 MI ROUNDTRIP TO HWY; CIRCLE AND RETURN TO ZZZ. AT AROUND XA27; I EXPERIENCED AN 80% RPM LOSS ABOUT 1 MI N OF HWY AT AN ALT OF +2500 FT MSL. AT XA30 I MADE AN EMER LNDG ON HWY APPROX 9 MI W OF ABC. THE ACFT DID NOT SUSTAIN ANY DAMAGE NOR WAS ANYONE ENDANGERED OR HURT. THE CAUSE OF RPM LOSS HAS NOT YET BEEN DETERMINED. THE WINGS WERE REMOVED AND THE ACFT WAS TRUCKED BACK TO ZZZ.

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.

A C172 pilot experienced an unexplained 80% RPM loss. An emergency highway landing followed with no damage or injuries.