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|
Attributes | |
ACN | 401321 |
Time | |
Date | 199805 |
Day | Mon |
Local Time Of Day | 1201 To 1800 |
Place | |
Locale Reference | atc facility : rvs |
State Reference | OK |
Altitude | msl bound lower : 1100 msl bound upper : 1100 |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Controlling Facilities | tower : rvs |
Operator | general aviation : instructional |
Make Model Name | Skyhawk 172/Cutlass 172 |
Operating Under FAR Part | Part 91 |
Flight Phase | climbout : takeoff climbout : initial |
Flight Plan | VFR |
Person 1 | |
Affiliation | Other |
Function | flight crew : single pilot |
Qualification | pilot : private |
Experience | flight time last 90 days : 23 flight time total : 111 flight time type : 16 |
ASRS Report | 401321 |
Person 2 | |
Affiliation | government : faa |
Function | controller : local |
Qualification | controller : non radar |
Events | |
Anomaly | aircraft equipment problem : critical other anomaly other |
Independent Detector | other flight crewa |
Resolutory Action | flight crew : declared emergency none taken : unable other |
Consequence | Other |
Supplementary | |
Primary Problem | Aircraft |
Narrative:
The elevator was stuck in the climb position after takeoff. I rotated at 55 KTS and held the aircraft until vy (84 KTS) was reached. During the climb with nose down trim I tried to push the aircraft nose down for level flight, but it would not leave the climb attitude. I pushed the yoke forward with my knee to help my arms to avoid stalling. I verified the flaps up, gear up, and trim in nose down position. I proceeded with full nose down trim until it stopped and momentarily let go of the yoke -- nothing happened, the aircraft continued to climb. Then I put the trim wheel in the neutral position thinking the trim had stuck and the aircraft continued to climb. Next I put the trim back to full nose down attempting to get some leverage. All the gauges in the aircraft were fine and in the green. I declared an emergency. I attempted to land on runway 31 but could not due to a tail wind and too high a ground speed. At this time I was still forcing the nose down with my arms and the trim was still full nose down. Attempted landing on runway 19R and made it. The aircraft bounced hard on landing due to lack of elevator control. I cleared the runway and taxied back to the ramp. At the ramp I was met by safety officer and line lead. The safety officer got the elevator to stay in the up position. The preflight of the aircraft was routine until reaching the elevator. I moved the elevator up and down on the flight instructor's side of the aircraft and a rod (in a hole near the tail) would twist when moved. I went and got the mechanic to come and look at it. He said that it was normal due to a sprocket and cables in the tail. I taxied to the runup area. Everything was normal. The first takeoff was normal. The next takeoff and landing was normal. The next takeoff was normal until about 1200 ft when the incident occurred. The mechanic allowed the instructor to go fly the aircraft because maintenance could not find anything wrong. Maintenance man lubricated the joints. It was found that the trim was wrong in the aircraft. When the trim was in the neutral position indicated it was too nose up. The lack of lubrication also could have caused the elevator jam. The maintenance man downed the aircraft. There has not been a definite cause to the problem. During the climb, nothing I tried would get the nose down except excessive force pushing against the yoke. The aircraft was a C172RG. Callback conversation with reporter revealed the following information: reporter states it has been determined that the trim indicator was inaccurate and also the trim. So the problem was strictly a mechanical one and no reason could be found for this to happen. The statement about the rod which twisted in the preflight procedures was explained as a rod which connects to a sprocket and attaches to the trim. About two weeks later reporter went on a check flight with an instructor and made three perfect lndgs so there seems to be no residual effects from the experience. The aircraft, a 172RG is flying again.
Original NASA ASRS Text
Title: PLT OF A C172RG HAS ELEVATOR JAM IN THE UP POSITION. UNABLE TO KEEP THE ACFT FROM CLBING, BOTH HANDS AND KNEE ARE USED TO GET THE ACFT BACK AROUND AND LAND.
Narrative: THE ELEVATOR WAS STUCK IN THE CLB POS AFTER TKOF. I ROTATED AT 55 KTS AND HELD THE ACFT UNTIL VY (84 KTS) WAS REACHED. DURING THE CLB WITH NOSE DOWN TRIM I TRIED TO PUSH THE ACFT NOSE DOWN FOR LEVEL FLT, BUT IT WOULD NOT LEAVE THE CLB ATTITUDE. I PUSHED THE YOKE FORWARD WITH MY KNEE TO HELP MY ARMS TO AVOID STALLING. I VERIFIED THE FLAPS UP, GEAR UP, AND TRIM IN NOSE DOWN POSITION. I PROCEEDED WITH FULL NOSE DOWN TRIM UNTIL IT STOPPED AND MOMENTARILY LET GO OF THE YOKE -- NOTHING HAPPENED, THE ACFT CONTINUED TO CLB. THEN I PUT THE TRIM WHEEL IN THE NEUTRAL POSITION THINKING THE TRIM HAD STUCK AND THE ACFT CONTINUED TO CLB. NEXT I PUT THE TRIM BACK TO FULL NOSE DOWN ATTEMPTING TO GET SOME LEVERAGE. ALL THE GAUGES IN THE ACFT WERE FINE AND IN THE GREEN. I DECLARED AN EMER. I ATTEMPTED TO LAND ON RWY 31 BUT COULD NOT DUE TO A TAIL WIND AND TOO HIGH A GND SPD. AT THIS TIME I WAS STILL FORCING THE NOSE DOWN WITH MY ARMS AND THE TRIM WAS STILL FULL NOSE DOWN. ATTEMPTED LANDING ON RWY 19R AND MADE IT. THE ACFT BOUNCED HARD ON LANDING DUE TO LACK OF ELEVATOR CTL. I CLRED THE RWY AND TAXIED BACK TO THE RAMP. AT THE RAMP I WAS MET BY SAFETY OFFICER AND LINE LEAD. THE SAFETY OFFICER GOT THE ELEVATOR TO STAY IN THE UP POSITION. THE PREFLT OF THE ACFT WAS ROUTINE UNTIL REACHING THE ELEVATOR. I MOVED THE ELEVATOR UP AND DOWN ON THE FLT INSTRUCTOR'S SIDE OF THE ACFT AND A ROD (IN A HOLE NEAR THE TAIL) WOULD TWIST WHEN MOVED. I WENT AND GOT THE MECH TO COME AND LOOK AT IT. HE SAID THAT IT WAS NORMAL DUE TO A SPROCKET AND CABLES IN THE TAIL. I TAXIED TO THE RUNUP AREA. EVERYTHING WAS NORMAL. THE FIRST TKOF WAS NORMAL. THE NEXT TKOF AND LNDG WAS NORMAL. THE NEXT TKOF WAS NORMAL UNTIL ABOUT 1200 FT WHEN THE INCIDENT OCCURRED. THE MECH ALLOWED THE INSTRUCTOR TO GO FLY THE ACFT BECAUSE MAINT COULD NOT FIND ANYTHING WRONG. MAINT MAN LUBRICATED THE JOINTS. IT WAS FOUND THAT THE TRIM WAS WRONG IN THE ACFT. WHEN THE TRIM WAS IN THE NEUTRAL POSITION INDICATED IT WAS TOO NOSE UP. THE LACK OF LUBRICATION ALSO COULD HAVE CAUSED THE ELEVATOR JAM. THE MAINT MAN DOWNED THE ACFT. THERE HAS NOT BEEN A DEFINITE CAUSE TO THE PROBLEM. DURING THE CLB, NOTHING I TRIED WOULD GET THE NOSE DOWN EXCEPT EXCESSIVE FORCE PUSHING AGAINST THE YOKE. THE ACFT WAS A C172RG. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATES IT HAS BEEN DETERMINED THAT THE TRIM INDICATOR WAS INACCURATE AND ALSO THE TRIM. SO THE PROBLEM WAS STRICTLY A MECHANICAL ONE AND NO REASON COULD BE FOUND FOR THIS TO HAPPEN. THE STATEMENT ABOUT THE ROD WHICH TWISTED IN THE PREFLT PROCS WAS EXPLAINED AS A ROD WHICH CONNECTS TO A SPROCKET AND ATTACHES TO THE TRIM. ABOUT TWO WEEKS LATER RPTR WENT ON A CHECK FLT WITH AN INSTRUCTOR AND MADE THREE PERFECT LNDGS SO THERE SEEMS TO BE NO RESIDUAL EFFECTS FROM THE EXPERIENCE. THE ACFT, A 172RG IS FLYING AGAIN.
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.