CFM56-5A inlet cowl
The engines used in the Airbus A319 and A320 are fitted with inlet cowl acoustic panels which experience serious corrosive damage after only a relatively short operating period. Lufthansa Technik Airframe Related Components (ARC®) offers a repair which provides a long-lasting remedy.
The issue
The inlet cowl acoustic panels of the engine are built CFM56-5A out of a honeycomb structure that is finished on the outside with an aluminum sheet. As there is no provision for drainage, depending on the operating conditions, sooner or later the structure becomes corroded. The extent of the damage rules out the possibility of a local repair or makes it uneconomic.
Our solution
Working with a specialist company in the USA, Lufthansa Technik has developed a new acoustic cowl inner barrel as an integral component constructed out of high-grade steel. It is not only a lot more robust than the composite unit, but also significantly less expensive. At the same time, the integral structure of the new steel acoustic inner barrel, which is manufactured with a patented welding process, weighs exactly the same as the original structure. Another major advantage of the new component is the reduced complexity of removing and installing the new inner barrel. It is delivered as a unit complete with mounting flange and is installed using an existing jig.
More robust and less expensive
A welcome side-effect of the integral design is the enlargement of the effective sound dampening surface. This is due to the fact that fasteners are no longer required between the individual segments, and this means higher limits during repairs in this area. Moreover, future repairs can be accomplished more efficiently, contributing to further cost savings. Simple external doubler repairs, which can also be carried out on-wing, are permitted in flight operations. The steel inner barrel from ARC® is an extremely efficient and durable solution for all operators of the CFM56-5A engine and is another example of the cost-saving solutions offered by ARC®. The new structure is evaluated and proven in the Lufthansa fleet.
