|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||1201 To 1800|
|Locale Reference||navaid : ccr.vor|
|Altitude||msl single value : 3500|
|Controlling Facilities||tower : ccr.tower|
|Operator||general aviation : instructional|
|Make Model Name||Skyhawk 172/Cutlass 172|
|Operating Under FAR Part||Part 91|
|Flight Phase||cruise : level|
|Function||instruction : instructor|
|Qualification||pilot : multi engine|
pilot : instrument
pilot : commercial
pilot : cfi
|Experience||flight time last 90 days : 200|
flight time total : 1100
flight time type : 1000
|Function||instruction : trainee|
|Anomaly||aircraft equipment problem : critical|
other anomaly other
|Independent Detector||other flight crewa|
|Resolutory Action||flight crew : landed as precaution|
Flight Crew Human Performance
About 3 mi north of ccr VOR, our C172 had a rough engine at 3500 ft MSL. Tried to troubleshoot and flow check, but it didn't work. Therefore, I requested priority landing over the concord airport (buchanan field) and landed on runway 19R. After landing, checked magnetos and mixture, etc, but the student and I couldn't find out what was wrong. The temperature at 3500 ft MSL was about 25 degrees C. No signs of carburetor icing, no signs of magneto problems. Callback conversation with reporter revealed the following information: reporter elaborated that the engine roughness resulted in reduced power availability and that he requested priority landing clearance rather than declare an emergency because he felt that failure was not imminent. They were unable to quickly determine a cause after landing and left the aircraft with a maintenance facility. Reporter is unaware of the ultimate evaluation of the problem.
Original NASA ASRS Text
Title: FLT INSTRUCTOR AND STUDENT SUFFER ENG ROUGHNESS AND PARTIAL LOSS OF PWR OVERHEAD CCR. REQUEST AND RECEIVE PRIORITY HANDLING FOR LNDG.
Narrative: ABOUT 3 MI N OF CCR VOR, OUR C172 HAD A ROUGH ENG AT 3500 FT MSL. TRIED TO TROUBLESHOOT AND FLOW CHK, BUT IT DIDN'T WORK. THEREFORE, I REQUESTED PRIORITY LNDG OVER THE CONCORD ARPT (BUCHANAN FIELD) AND LANDED ON RWY 19R. AFTER LNDG, CHKED MAGNETOS AND MIXTURE, ETC, BUT THE STUDENT AND I COULDN'T FIND OUT WHAT WAS WRONG. THE TEMP AT 3500 FT MSL WAS ABOUT 25 DEGS C. NO SIGNS OF CARB ICING, NO SIGNS OF MAGNETO PROBS. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR ELABORATED THAT THE ENG ROUGHNESS RESULTED IN REDUCED PWR AVAILABILITY AND THAT HE REQUESTED PRIORITY LNDG CLRNC RATHER THAN DECLARE AN EMER BECAUSE HE FELT THAT FAILURE WAS NOT IMMINENT. THEY WERE UNABLE TO QUICKLY DETERMINE A CAUSE AFTER LNDG AND LEFT THE ACFT WITH A MAINT FACILITY. RPTR IS UNAWARE OF THE ULTIMATE EVALUATION OF THE PROB.
Data retrieved from NASA's ASRS site as of July 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.