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Aa-5B flight instructor reported a flap asymmetry condition in flight.
| Attributes | |
| ACN | 1509079 |
| Time | |
| Date | 201712 |
| 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 | Cheetah Tiger Traveler AA5 Series |
| Operating Under FAR Part | Part 91 |
| Flight Phase | Cruise |
| Flight Plan | None |
| Component | |
| Aircraft Component | Trailing Edge Flap |
| Person 1 | |
| Function | Instructor |
| Qualification | Flight Crew Flight Instructor Flight Crew Multiengine Flight Crew Instrument Flight Crew Commercial |
| Experience | Flight Crew Last 90 Days 35 Flight Crew Total 1200 Flight Crew Type 90 |
| Events | |
| Anomaly | Aircraft Equipment Problem Less Severe |
Narrative:
Upon recovering to 90kts 'maneuvering cruise' flight after demonstrating a stall; it was noted that an annoying level of right pressure was required on the flight controls to maintain wings level. At first I attributed this to a fuel imbalance; though it didn't quite make sense that such an imbalance would have developed in such a short time. Looking out at the right wing I then noted that the right flap had not retracted fully; and was still extended perhaps 2 to 7 degrees (estimated). I made the decision to terminate the flight; and took control from my student for the remainder of the flight; though I continued to talk them through my adm; so they could learn from the real-world lesson. Evaluating the situation; I elected to remain within a reduced flight envelope near the point that had already been proven. This meant maintaining speed at or below 90kts; throttle setting at or below about 2100 RPM; roughly 1g load factor; and no further flap setting changes. Rather than return to the airport of departure; which was beyond some hills creating orographic turbulence that could have added to the load factor; I elected to return to a nearby airport that had long; wind-aligned runways; this would provide ample margin for a no-flap landing and obviate the necessity for any side slip aerodynamic forces from a crosswind landing. I approached and landed without issue; and taxied to parking. Looking over the flap; someone wiggled it; and it popped right back to its normal position. The suspect roller was greased; the flap mechanism was inspected; and no further issue arose.
Original NASA ASRS Text
Title: AA-5B Flight Instructor reported a flap asymmetry condition in flight.
Narrative: Upon recovering to 90kts 'maneuvering cruise' flight after demonstrating a stall; it was noted that an annoying level of right pressure was required on the flight controls to maintain wings level. At first I attributed this to a fuel imbalance; though it didn't quite make sense that such an imbalance would have developed in such a short time. Looking out at the right wing I then noted that the right flap had not retracted fully; and was still extended perhaps 2 to 7 degrees (estimated). I made the decision to terminate the flight; and took control from my student for the remainder of the flight; though I continued to talk them through my ADM; so they could learn from the real-world lesson. Evaluating the situation; I elected to remain within a reduced flight envelope near the point that had already been proven. This meant maintaining speed at or below 90kts; throttle setting at or below about 2100 RPM; roughly 1g load factor; and no further flap setting changes. Rather than return to the airport of departure; which was beyond some hills creating orographic turbulence that could have added to the load factor; I elected to return to a nearby airport that had long; wind-aligned runways; this would provide ample margin for a no-flap landing and obviate the necessity for any side slip aerodynamic forces from a crosswind landing. I approached and landed without issue; and taxied to parking. Looking over the flap; someone wiggled it; and it popped right back to its normal position. The suspect roller was greased; the flap mechanism was inspected; and no further issue arose.
Data retrieved from NASA's ASRS site 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.