Learjet 35
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Landed As Precaution; Flight Crew Returned To Departure Airport; Flight Crew Inflight Shutdown; General Flight Cancelled / Delayed; General Maintenance Action
Aircraft; Procedure
The crew conducted a Maintenance Test Flight; to test the repairs made on the Right Engine Fire Loop. During the climb phase of the flight while passing FL380; the crew observed the R/H Fire T-Handle illuminate flashing associated with a flashing Master Warning indication. As the crew was expecting this possible indication during the flight; the on board Mechanic was notified to observe the indications. Immediately afterwards the crew began to perform the memory items of the QRH ENGINE FIRE Checklist in an effort to extinguish the illuminated/flashing T-handle. After performing all memory items followed by the QRH checklist; the Engine Fire T-Handle continued to flash. The PIC (Pilot in Command) asked the on board Mechanic to observe if there was any indication of engine fire outside the window to which he confirmed there was not. ITT Engine indications also confirmed that there was no indication of an actual engine fire. As the aircraft was now single engine; the crew [requested priority handling] with ATC and elected to return to ZZZ. The aircraft landed safely and without incident. No suggestions at this time.
LJ35 Captain reported an air turnback after an IFSD during a maintenance check to test an engine fire loop was unsuccessful.