Flight Crew Multiengine; Flight Crew Flight Instructor; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 95; Flight Crew Total 9483; Flight Crew Type 1300
Aircraft Equipment Problem Critical
Flight Crew Landed in Emergency Condition; Flight Crew Diverted; General Maintenance Action
Aircraft
I was administering a private pilot ASEL add-on to a commercial rated helicopter applicant with instrument helicopter rating as well.  During recovery from emergency descent; myself and applicant heard loud bang.  Sounded like baggage door opening.  Applicant stated he was having trouble flying aircraft and asked me to fly aircraft.  IAS approximately 80 knots; altitude 1000 FTt.  At 80 knots; I had trouble keeping aircraft going straight.  Full left aileron; approximately full left rudder.  I decided to slow aircraft and climb to approximately 2500 FT.  At 2500 FT; I slowed aircraft to determine controllability at different airspeeds.  Decision was made to fly 70 knots IAS on final.  At this point we were 19 NM NW of ZZZ with left flap at approximately 30 degrees; right flap 0 degrees.  Flew back and landed; wind approximately 090 degrees at 10 gusting 13.  Landed without incident.  My concerns: 1) Is this an 'AD' concern? 2) Based on my experience; I believe this would be a major flight control issue for a private pilot. 3) I am 6'4' and it was very uncomfortable flying aircraft in this condition due to flight control pressures required to maintain control.
The flaps had been extended during the emergency descent with the left flap failing to retract during clean up from the maneuver.  The reporter states that consideration was given to extending the right flap and rejected due to the fact that the aircraft was controllable and the possibility of making the situation worse.  Post flight revealed that a left flap track bearing had failed causing the flap to jam.  The cable connection between the left and right flap had snapped and was likely responsible for the loud bang that was heard.  Flaps had been manually preflighted by both pilots during the walk around prior to flight.
C172 Examiner reports a left flap jammed at 30 degrees when the flaps are selected up after an emergency descent with the examinee at the controls.  Examinee passes control of the aircraft to the Examiner due to controlability issues.  Reporter finds aircraft marginally controllable but is able to climb and land at a suitable airport.