Lyon, France-based fuel-leak repair specialist Sunaero (also known as Aerowing in the U.S.) is offering its services to the helicopter industry, pledging significant time savings over conventional detection and repair methods.
Increasingly complex fuel-tank shapes have raised new challenges, Sunaero vice president Thierry Regond told AIN. Small but serious leaks, whether they originate from vibration wear or manufacturing defects, are difficult to locate and can force missions to be scrubbed, as one European country’s police force recently discovered, Regond said.
The technology Sunaero uses on helicopters was developed at the U.S. Navy’s request to repair F/A-18s. That fighter has flexible fuel tanks, just like the bladders aboard rotorcraft. The technology uses a tracer gas (typically helium) to detect leaks, considerably simplifying the detection process. For example, testing an underfloor tank requires the removal of only one floor slab, according to Regond.
A fast curing process using broadband, low-temperature infrared seals the patch swiftly. The working temperature remains below 50 degrees C (122 degrees F), eliminating the risk of explosion. The infrared energy also cleans away any fuel (and its telltale odor) that had leaked. The process takes about eight hours instead of the usual 72 hours, according to Sunaero. Repairs are limited in size, however, and the process cannot be used on a torn bladder.
Sunaero has performed fuel-leak repair services on all major brands of helicopter, and the manufacturer only has to issue its approval, Regond said.
Sunaero can train manufacturer employees to perform quality-control checks before delivery, and it can also train MRO providers and aircraft operators. As of early last month, a German company was nearing a deal with Sunaero to be the first MRO company to use Sunaero’s system.