|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||0601 To 1200|
|Locale Reference||atc facility : adm|
|Altitude||msl bound lower : 1500|
msl bound upper : 4000
|Controlling Facilities||artcc : zfw|
|Operator||general aviation : instructional|
|Make Model Name||Small Aircraft, Low Wing, 1 Eng, Fixed Gear|
|Flight Phase||cruise other|
|Function||instruction : instructor|
|Qualification||pilot : commercial|
pilot : cfi
pilot : instrument
|Experience||flight time last 90 days : 150|
flight time total : 890
flight time type : 25
|Function||instruction : trainee|
|Qualification||pilot : private|
|Anomaly||altitude deviation : excursion from assigned altitude|
inflight encounter : weather
|Independent Detector||other flight crewa|
|Resolutory Action||flight crew : regained aircraft control|
|Primary Problem||Flight Crew Human Performance|
|Air Traffic Incident||other|
We were northbound on 343 degree right off ardmore at 4000'. Turned on autoplt for about 3 mins, then all of sudden were in a 90 degree bank going down at 3000 FPM. Turned autoplt off, pulled power, pulled fuse for autoplt, turned on carburetor heat, lost 80% engine power, took bank out slowly, broke out about 1500' MSL level airplane pitch up to level flight about 300' above ground, got bearing, and turned left to 350 degrees. 3 mi to pauls valley airport. Flew plane with 1200 RPM to airport and landed. I think autoplt on small aircraft should be checked and tested more often. Callback conversation with reporter revealed the following: did not have pitot heat on at time of incident. Gave the aircraft type and autoplt model. Did not feel he had any problem with the static system. Admitted however when in the descent he put the carburetor heat on and knew that was probably the trouble with the engine. Air was extremely smooth, but he was flying in clouds for training for the student working on an instrument rating. When he took the aircraft the student called the center and advised they were in 90 degree bank descending at 3000 FPM. Did not declare emergency or set transponder to 7700. Apparently no loss of sep. Maintenance checked the aircraft over and found no irregularities and flew the aircraft to home base using the autoplt and everything worked perfectly.
Original NASA ASRS Text
Title: IFR TRAINING FLT AUTOPLT GIVES HARD OVER SIGNAL RESULTING IN UPSET.
Narrative: WE WERE NBOUND ON 343 DEG R OFF ARDMORE AT 4000'. TURNED ON AUTOPLT FOR ABOUT 3 MINS, THEN ALL OF SUDDEN WERE IN A 90 DEG BANK GOING DOWN AT 3000 FPM. TURNED AUTOPLT OFF, PULLED PWR, PULLED FUSE FOR AUTOPLT, TURNED ON CARB HEAT, LOST 80% ENG PWR, TOOK BANK OUT SLOWLY, BROKE OUT ABOUT 1500' MSL LEVEL AIRPLANE PITCH UP TO LEVEL FLT ABOUT 300' ABOVE GND, GOT BEARING, AND TURNED LEFT TO 350 DEGS. 3 MI TO PAULS VALLEY ARPT. FLEW PLANE WITH 1200 RPM TO ARPT AND LANDED. I THINK AUTOPLT ON SMA SHOULD BE CHKED AND TESTED MORE OFTEN. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: DID NOT HAVE PITOT HEAT ON AT TIME OF INCIDENT. GAVE THE ACFT TYPE AND AUTOPLT MODEL. DID NOT FEEL HE HAD ANY PROB WITH THE STATIC SYS. ADMITTED HOWEVER WHEN IN THE DSCNT HE PUT THE CARB HEAT ON AND KNEW THAT WAS PROBABLY THE TROUBLE WITH THE ENG. AIR WAS EXTREMELY SMOOTH, BUT HE WAS FLYING IN CLOUDS FOR TRNING FOR THE STUDENT WORKING ON AN INSTRUMENT RATING. WHEN HE TOOK THE ACFT THE STUDENT CALLED THE CENTER AND ADVISED THEY WERE IN 90 DEG BANK DSNDING AT 3000 FPM. DID NOT DECLARE EMER OR SET TRANSPONDER TO 7700. APPARENTLY NO LOSS OF SEP. MAINT CHKED THE ACFT OVER AND FOUND NO IRREGULARITIES AND FLEW THE ACFT TO HOME BASE USING THE AUTOPLT AND EVERYTHING WORKED PERFECTLY.
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.