Quiet Technology Aerospace (QTA) has received FAA STC approval for its eighth airframe specific carbon fibre engine inlet replacement barrel. This STC offers a terminating solution for Gulfstream G450 and the shorter range G350 aircraft over the plaguing issue of engine inlet cowl inner barrel corrosion on Rolls Royce Tay Mark 611-8C turbofan engine inlets.
Combating an expensive and time-consuming problem of aluminium engine inlet cowl inner-barrel corrosion and acoustic screen degradation on the 365 Gulfstream G450/350 series aircraft in service, QTA replaces the aluminum based inner barrel with a lighter weight state-of-the-art carbon graphite composite barrel that terminates the root cause of the corrosion issue and comes with a lifetime warranty that remains with the aircraft's serial number and transfers to any future owner. It is the only permanent solution available today.
An additional significant benefit to the QTA G450/350 replacement barrels is a weight saving of 30 pounds per inlet.
When installed, the inlets appearance is better than originally manufactured. This is not a repair to the original aluminium inlet which will certainly fail again, potentially causing engine damage; It is a permanent and terminating solution to the corrosion issue.
The Gulfstream G450 solution is QTA's eighth approved STC in its carbon fibre engine inlet solution programme that began in 2015. Other inner barrel corrosion affected airframes benefitting from QTA's engineering and carbon fibre manufacturing are the Learjet 60, Gulfstream G200 and G280, Hawker 1000, Falcon 2000LX/EX, Challenger 300/350 as well as the Embraer Legacy 450/500 and Praetor 500/600 series.
In its 35-year history, exactly zero of QTA's inlet upgrades have failed on aircraft operating over 20 years. The company's first inlet upgrade was for the Douglas DC-8 in 1988.
To minimise aircraft down time QTA offers a guaranteed fixed price inlet exchange programme that keeps aircraft in operation. For operators undergoing a major inspection, then QTA can upgrade a complete set of inlet cowls for the customer's aircraft in four weeks.
QTA's carbon graphite composite inner barrel comes with a lifetime warranty, assigned to the aircraft's serial number that automatically transfers to any future owner. The QTA upgraded inlet cowls have lifetime product liability insurance placed via Lloyds of London. The combined product warranty and liability insurance provides owner confidence for total coverage over the life of the aircraft.
Since the carbon fibre inner barrel replacement programme began in 2015, operators of affected aircraft have shown enthusiastic support of QTA's technology and the manufacturing quality of its product. QTA has installed over 250 carbon fibre inlet barrels on 135 aircraft around the globe. Operators are both relieved from the corrosion problem that has plagued their engines inlets and impressed with the quality and reasonable pricing of the QTA solution.
Martin Gardner, executive VP of engineering and customer service of the company's composite barrel programme, describes the corrosion problem and its underlying cause: “There is a generation of aircraft where the need for increased acoustic sound suppression in the inlet was achieved through adding an acoustic screen over the traditional aluminum honeycomb panels with open perforated face sheets that make the inner barrel. The acoustic screen is a permeable fine woven wire mesh and is a powerful acoustic tool. Unfortunately, in the quest for increased sound attenuation, the effect of moisture entrapment in the aluminum inner barrel honeycomb cells was not contemplated. Previous generation inlet cowls with open perforated holes are self-drying, the engine vacuums the moisture out; this does not happen when the acoustic screen is added. This results in moisture being trapped in the cells.
“The end result is guaranteed eventual corrosion of the aluminum honeycomb and perforated face sheet which will render the Inlet un-airworthy.”
QTA CEO Barry Fine adds: “With our eighth STC approval finalised for the Gulfstream G450/350 series aircraft, QTA now has a permanent and terminating corrosion fix for over 2,688 aircraft operating around the world. That represents a large amount of time and money saved to operators that have been continuously troubled by expensive and time-consuming inner barrel corrosion on their original OEM inlet cowls, not to mention the already documented danger of engines ingesting corroded aluminum while operating. The carbon fibre inlet programme insures QTA customers a safe, simple and quick experience when upgrading that is most of all, cost efficient and final. Ours is the industry's only permanent solution. Our solution offers a permanent solution to the issue of corrosion and a substantial weight reduction for G450 operators. A repair does not eliminate the corrosion issue and the only guarantee you have is that it will fail again.”