Brief Summary

A support team was initially contacted regarding a flap fault on an aircraft stationed in Georgia. The expectation was a routine investigation involving a possible flap control unit reset, wiring checks or a straightforward mechanical release. Upon arrival, however, the situation escalated when a fuel bowser rolled into the right wing, leaving the vehicle lodged beneath the structure. The event evolved into a structural repair operation involving damage mapping, temporary flap repair and replacement of several components. What began as an anticipated quick fix ultimately became a complex, multi-day AOG recovery.

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Initial Assessment

The operator first reported a flap fail message during approach, with the flaps refusing to extend beyond an intermediate position. Such symptoms can arise from mechanical binding, actuator anomalies or invalid transducer feedback, all of which are monitored by the aircraft’s flap control logic. As the fault appeared consistent with a control unit or position-sensor disagreement, the team departed the United Kingdom carrying the necessary tools for data downloads, wiring continuity checks, and a potential reset.

Because the UK does not operate direct flights to Georgia, the journey required multiple connections. The team arrived late in the evening, checked into a nearby hotel and attempted to grab dinner before preparing for the following day’s inspection. One hour into dinner, the operator issued an urgent update advising of a new event. A fuel bowser, left with its parking brake insufficiently secured, had rolled and become physically jammed beneath the aircraft’s right wing. The team was instructed to attend immediately the next morning to assess the damage.

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Diagnostic Approach

The following morning the bowser remained lodged under the wing. To separate the aircraft from the vehicle without causing further structural damage, the team agreed to over-inflate the right main landing gear oleo to raise the wing slightly. Increasing oleo pressure is an accepted technique for creating clearance during ground incidents, although it must be carried out with strict weight-and-balance control. The manoeuvre successfully created the gap required for the bowser to be removed without additional deformation.

Once the aircraft was moved into a hangar, detailed damage mapping began. The right-hand flap assembly, right winglet and right aileron were all found to be beyond structural limits. Composite fractures on the winglet panels, distortion of flap track fairings and hinge misalignment indicated energy transfer well above typical ground-handling damage.

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Communication and Planning

The operator’s maintenance control centre was briefed on the expanded scope. Rather than a routine FCU reset, the recovery now required structural assessment, parts sourcing, composite repair and a decision on whether permanent repairs could be completed on site.

While the team planned the repair strategy, a film crew was using the hangar as a temporary medic bay for an Afghanistan-themed production. Once cleared, the aircraft was moved inside for controlled inspection. Reference was made to previous escalation scenarios, such as those described in the reversed AC phases case on AeroTechCareers which demonstrate how quickly simple faults can evolve into multi-system recoveries:

The consensus was that a permanent repair was essential before repositioning, since both the winglet, flap and aileron were beyond any ferry-flight structural allowance.

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Logistics and Installation

A new aileron was ordered, along with four replacement winglet composite panels. A temporary flap repair kit was sourced to allow the aircraft to regain airworthiness for a controlled relocation once the structural conditions were met. Importation into Georgia required coordination with both customs authorities and the airport operator, a process complicated by varying handling capabilities.

Over several days, the team removed damaged components, fitted the new winglet panels, installed the replacement aileron and carried out a temporary restoration of the flap mechanism.

Because the facility lacked full jacking capability, defuel equipment and flap-replacement stands, the team prepared the aircraft for a ferry flight to a maintenance base better equipped for final work. This logistical escalation is frequently noted in other case studies, such as the double wingtip strike incident.

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Testing and Return to Service

Once the temporary repair was completed, the flap system underwent a full ground functional test. Engineers monitored position transducers, asymmetry protection logic, motor current draw and mechanical travel limits. All readings matched allowable tolerances for a short repositioning sector.

The aircraft was released under an approved maintenance ferry permit. At the destination base, engineers performed a complete flap replacement, including full defuel, jacking and rigging checks. Upon completion, the aircraft passed all post-maintenance tests and was released back to service.

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Technical Reflection

The successful use of oleo over-inflation to free the aircraft shows the value of flexible, practical problem-solving in AOG situations. The escalation from a suspected flap control unit reset to extensive structural repairs is a reminder for AOG teams: the reported fault is often just the beginning.

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And if you ever find yourself in Tbilisi, Georgia, the Biltmore Hotel is worth checking out for sure.