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|
Attributes | |
ACN | 1018599 |
Time | |
Date | 201206 |
Local Time Of Day | 1201-1800 |
Place | |
Locale Reference | ZZZ.Airport |
State Reference | US |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Make Model Name | Skyhawk 172/Cutlass 172 |
Operating Under FAR Part | Part 91 |
Flight Phase | Landing |
Route In Use | Visual Approach |
Flight Plan | None |
Component | |
Aircraft Component | Flap Control (Trailing & Leading Edge) |
Person 1 | |
Function | Instructor |
Qualification | Flight Crew Flight Instructor Flight Crew Instrument Flight Crew Commercial |
Experience | Flight Crew Last 90 Days 129 Flight Crew Total 590 Flight Crew Type 300 |
Events | |
Anomaly | Aircraft Equipment Problem Critical Deviation - Speed All Types Inflight Event / Encounter Loss Of Aircraft Control |
Narrative:
The flight was a training flight out and back from our home airport with one intermediate stop. A thorough preflight per the flight schools checklist was performed prior to engine start that was unremarkable; no abnormalities were discovered. We flew to the northeast practice area where multiple training maneuvers were performed; then landed and departed our intermediate stop uneventfully. On the return flight we agreed to complete two to three touch and goes; time permitting; at our home airport. The student was given the responsibility to maintain directional control of the aircraft on the runway; including rudder; yoke; and throttle control while I was to retract the flaps and trim the aircraft. These responsibilities were delegated per the suggestions in the FAA aircraft flying handbook. We entered the traffic pattern and successfully completed the first touch and go. On the second touch and go we landed with 30 degrees of flaps and the student completed his responsibilities as I selected 10 degrees of flaps (per the recommended takeoff flap setting in the flight school's checklist); visually noted that the flaps were retracting from the 30 degree position and reset the trim per the takeoff checklist as the student applied full power. The aircraft lifted off prematurely at 52 KTS (normal rotation is at 55 KTS) and the aircraft accelerated in ground effect uneventfully to approximately 57 KTS and climbed to an altitude of approximately 300 ft MSL. At this point the aircraft's airspeed began to drop quickly and I took command of the controls and performed did a cockpit scan: flight instruments checked normal; engine instruments checked normal; and the flaps were selected at 10 degrees. The flap indicating needle adjacent to the flap selector showed a flap setting of 15 degrees but this was not suspicious in itself because the needle often indicates an error of +/- 5 degrees and is accurate only when the flaps are fully retracted or fully extended.however; I visually checked the flaps and noted they appeared to have retracted only to the 20 degree position despite the flaps being confirmed selected for 10 degrees. The instructor lowered the nose to a slightly nose down attitude to gain airspeed. At 300 ft MSL we were indicating a descent rate of 150 ft per minute and the aircraft was not gaining airspeed quickly enough to initiate a climb. This poor performance was further complicated by the effects of density altitude and the midday surface thermals from the ground causing light chop/turbulence.it appeared that a controlled off airport landing might be necessary if the airplane's descent could not be stabilized. Erring on the side of caution to ensure maximum safety of flight; I declared an emergency with the tower and advised we were unable to maintain altitude due to slow airspeed and a flap malfunction. The tower immediately cleared the airspace and made all runways available to the instructor's aircraft. At this point the airspeed was trending higher and I was able to initiate a gentle positive rate of climb at 60 KTS at approximately 100-200 ft per minute. A shallow; almost level turn was initiated to join the downwind of the active runway. The aircraft was able to climb to approximately 800 ft in the downwind leg prior to initiating a shallow and gentle turn to a safe landing. During the downwind leg we cycled the flap selector through the full range of flap options and were unable to retract the flaps. The circuit breakers were checked and none of the circuit breakers had been tripped. The flight school checklist and the poh were consulted for a flap malfunction and neither listed a checklist for this problem in either the normal or emergency procedures. After landing safely; the operations manager was specifically notified that this type of failure constitutes a flight control failure and that an immediate notification to the NTSB is required. The aircraft was squawked and grounded bythe flight instructor. A post flight review of all available checklists; flight maneuver descriptions/checklists; the poh and the airplane flying handbook was completed. No evidence was found requiring that the pilot in command of any aircraft completing a touch and go is required to visually confirm that the flaps have completely retracted to the correct takeoff position prior to opening the throttle and accelerating for liftoff/rotation. The only requirement is to select flaps appropriately per the takeoff checklist. A similar review of the aircraft owners and pilots association air safety foundation's (AOPA asf's) safety brief on touch and goes specifically mentions that aircraft equipped with electric flaps may open the throttle after selecting the correct flaps because electric flaps retract slowly and do not harmfully degrade aircraft performance during the retraction. Under normal operations; the flaps would have had sufficient time to retract to the 10 degree position prior to rotation.
Original NASA ASRS Text
Title: A C-172S Intructor pilot and his student lost control of vertical performance during a touch and go departure when the electric flaps failed to retract to the selected 10 degree extension; appearing to stop at 20 degrees deflection. The Instructor assumed control and eventually managed to accelerate and climb to a safe altitude from where a safe approach and landing were completed.
Narrative: The flight was a training flight out and back from our home airport with one intermediate stop. A thorough preflight per the flight schools checklist was performed prior to engine start that was unremarkable; no abnormalities were discovered. We flew to the northeast practice area where multiple training maneuvers were performed; then landed and departed our intermediate stop uneventfully. On the return flight we agreed to complete two to three touch and goes; time permitting; at our home airport. The student was given the responsibility to maintain directional control of the aircraft on the runway; including rudder; yoke; and throttle control while I was to retract the flaps and trim the aircraft. These responsibilities were delegated per the suggestions in the FAA Aircraft Flying Handbook. We entered the traffic pattern and successfully completed the first touch and go. On the second touch and go we landed with 30 degrees of flaps and the student completed his responsibilities as I selected 10 degrees of flaps (per the recommended takeoff flap setting in the flight school's checklist); visually noted that the flaps were retracting from the 30 degree position and reset the trim per the takeoff checklist as the student applied full power. The aircraft lifted off prematurely at 52 KTS (normal rotation is at 55 KTS) and the aircraft accelerated in ground effect uneventfully to approximately 57 KTS and climbed to an altitude of approximately 300 FT MSL. At this point the aircraft's airspeed began to drop quickly and I took command of the controls and performed did a cockpit scan: flight instruments checked normal; engine instruments checked normal; and the flaps were selected at 10 degrees. The flap indicating needle adjacent to the flap selector showed a flap setting of 15 degrees but this was not suspicious in itself because the needle often indicates an error of +/- 5 degrees and is accurate only when the flaps are fully retracted or fully extended.However; I visually checked the flaps and noted they appeared to have retracted only to the 20 degree position despite the flaps being confirmed selected for 10 degrees. The instructor lowered the nose to a slightly nose down attitude to gain airspeed. At 300 FT MSL we were indicating a descent rate of 150 FT per minute and the aircraft was not gaining airspeed quickly enough to initiate a climb. This poor performance was further complicated by the effects of density altitude and the midday surface thermals from the ground causing light chop/turbulence.It appeared that a controlled off airport landing might be necessary if the airplane's descent could not be stabilized. Erring on the side of caution to ensure maximum safety of flight; I declared an emergency with the Tower and advised we were unable to maintain altitude due to slow airspeed and a flap malfunction. The Tower immediately cleared the airspace and made all runways available to the instructor's aircraft. At this point the airspeed was trending higher and I was able to initiate a gentle positive rate of climb at 60 KTS at approximately 100-200 FT per minute. A shallow; almost level turn was initiated to join the downwind of the active runway. The aircraft was able to climb to approximately 800 FT in the downwind leg prior to initiating a shallow and gentle turn to a safe landing. During the downwind leg we cycled the flap selector through the full range of flap options and were unable to retract the flaps. The circuit breakers were checked and none of the circuit breakers had been tripped. The flight school checklist and the POH were consulted for a flap malfunction and neither listed a checklist for this problem in either the normal or emergency procedures. After landing safely; the operations manager was specifically notified that this type of failure constitutes a flight control failure and that an immediate notification to the NTSB is required. The aircraft was squawked and grounded bythe flight instructor. A post flight review of all available checklists; flight maneuver descriptions/checklists; the POH and the Airplane Flying Handbook was completed. No evidence was found requiring that the pilot in command of any aircraft completing a touch and go is required to visually confirm that the flaps have completely retracted to the correct takeoff position prior to opening the throttle and accelerating for liftoff/rotation. The only requirement is to select flaps appropriately per the takeoff checklist. A similar review of the Aircraft Owners and Pilots Association Air Safety Foundation's (AOPA ASF's) safety brief on touch and goes specifically mentions that aircraft equipped with electric flaps may open the throttle after selecting the correct flaps because electric flaps retract slowly and do not harmfully degrade aircraft performance during the retraction. Under normal operations; the flaps would have had sufficient time to retract to the 10 degree position prior to rotation.
Data retrieved from NASA's ASRS site as of July 2013 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.