Andrew Doyle/LONDON
THE FINNISH air force and flag carrier Finnair have each taken delivery of engine-compressor-wash systems from Sweden's Gas Turbine Efficiency, after carrying out a 12-month evaluation of the product.
The air force will use the GTE Cleaning System for all of its aircraft, including McDonnell Douglas F/A-18 Hornets, British Aerospace Hawks and Valmet Redigos. Finnair will initially use it for McDonnell Douglas (MDC) DC-9s and MD-80s. Similar systems for MDC DC-10 and MD-11 are under development.
Peter Asplund, president of GTE, which developed the technique in conjunction with Sweden's Volvo Aero Support, claims that the system can yield a 1% reduction in fuel consumption, reduce turbine-inlet temperatures and improve corrosion resistance. "A 1% saving in an airline's fuel budget is simply a lot of money," he says.
Airborne particles can cause a coating of dirt to form inside a jet engine, particularly in the compressor. This can reduce the efficiency of the compressor and "disturb" the airflow through the engine, degrading performance.
Operators have traditionally used abrasive particles, which can cause surface erosion, or large quantities of hazardous solvents to clean engines. GTE's system, however, uses surface-active agents (surfactants), which clean chemically by bonding with molecules of dirt to form a powder, which is cleared by the airflow.
GTE's method is based on the concept of using small amounts of small-particle fluid, instead of large amounts of large-particle fluid, to ensure that the fluid particles follow the same path as airborne particles through the engine. This means that any contamination should be removed from every part of the engine.
Other customers include the Swedish and Norwegian air forces, and Japan Air Commuter. GTE is also in negotiations with Scandinavian Airlines System.
Asplund says that GTE will eventually offer systems for most airliner types. "We have started with the most frequently used types - the DC-9, MD-80 and Boeing 737," he says, "but we have many more planned."
Source: Flight International
