PT6 Turbines Get “Green” Engine Wash
If you already fly or maintain some regional airliners and larger business jets, including the Bombardier CRJ200 and Global Express; Gulfstream IV and V/550; Dassault Falcon 2000EX and 7X; Embraer ERJ 145, 170 and 190; IAI Westwinds and Beechcraft King Air turboprops, you may already be familiar with an innovative, on-wing engine-cleansing system called EcoPower Wash.
If you’ve been waiting for EcoPower Wash for smaller turbine engines, particularly the Pratt & Whiney Canada PT6 turboprop and turboshaft engines, your wait is over. EcoPower for the PT6 became available on September 1. The first example of the PT6 EcoPower Wash System is on display here at NBAA 2013 at Booth No. C12039.
The EcoPower Wash System itself is fairly easy to understand, but like a casual fan at a baseball game, you may find the players on the field a bit confusing without a program. So here’s a quick rundown.
At the top of the lineup is Pratt & Whitney of Hartford, Conn., whose Line Maintenance Services unit developed the technology for EcoPower and began using it in 2005. The Pratt unit has performed some 40,000 engine washes with EcoPower. Pratt & Whitney is a division of United Technologies.
To sell and market EcoPower, Pratt & Whitney entered into a joint venture in December 2011 with Vision Technologies (VT) Aerospace, the aerospace arm of Singapore Technologies Engineering, to form a company called EcoServices, located in Wethersfield, Conn. In May 2012, VT Aerospace acquired the controlling interest (50.1 percent) in EcoServices. Headquartered in Alexandria, Va., VT Aerospace owns three aerospace companies in Mobile, Ala., and San Antonio.
About a year and a half ago, EcoServices and Vector-Hawk Aerospace joined forces to develop and market EcoPower for the popular PT6 family of engines. EcoServices designed the manifold and nozzles to fit the PT6 engine inlet along with a smaller version of the EcoPower large turbofan-engine wash unit.
Vector-Hawk, which is based in Daleville, Ala., and has “footprints” in Huntsville, Ala., and Tel Aviv, Israel, began demonstrating the system to potential customers, primarily military PT6 users. Vector-Hawk is a joint venture of Blackhawk Modification (Booth C7032) of Waco, Texas, and Vector Aerospace (Booth C8107), a global company with facilities in Canada, the U.S., the UK, France, Malaysia, Africa and Australia. Vector Aerospace is headquartered in Toronto.
Circling back to the EcoPower system, Mike Nowicki, president of Vector-Hawk, told AIN that the version of EcoPower for the PT6 primarily involves changes to the nozzle and manifold so that the system works with the engine’s 180-degree, reverse-flow design, which makes the compressor and power turbines behind the combustion chamber harder to reach for cleaning.
As mentioned, the Pratt folks designed the original EcoPower system for big turbofans. For the most part it’s relatively easy to spray water and cleaning solutions all the way through a turbofan while it is spinning with the igniters turned off. But this is messy and environmentally unfriendly. So the engineers designed EcoPower so that it not only collects 95 percent of the water sprayed through the engine, but also recycles it.
Also important is the fact that EcoPower does not use any detergent or other chemicals to clean the engine, but rather hot (about 140-degrees F), deionized water that is atomized into extremely tiny particles. This combination apparently does an extremely effective job cleaning the compressor, hot section and power turbine inside the engine.
Fuel Cost Savings
Talking about EcoPower’s effectiveness in turbofans, Nowicki mentioned Southwest Airlines, which he said has been using EcoPower cleansings at boarding gates for seven years. He said Southwest claims that the saving in fuel costs from flying with cleaner engines offsets the cost of an EcoPower unit after only a few cleanings.
The EcoPower system has other uses, too, including washing the aircraft. Combined with glycol, it can be used for de-icing. When used for engine washing, the pressure of the ionized water as it goes through the manifold is 950 psi, which is needed to create the extremely small droplet size. When the water exits the manifold nozzles and enters the engine, its pressure drop is only about 3 to 5 psi.
The EcoPower system for the PT6 includes a small wash unit, which contains the controls; a direct-drive, diesel-powered water pump; an electric heater; an exhaust-to-water heat exchanger and a 160-gallon water tank; an effluent collector, which rolls under the engine; a PT6 manifold, which installs on the engine’s inlet screen; high-pressure hoses; and a hand lance for cleaning aircraft surfaces. The diesel engine runs on diesel and jet fuel. It all fits on the bed of a pickup truck, but Vector-Hawk also offers an optional highway trailer. Dry weight of the system is 850 pounds; when the water tank is full, the unit weighs 1,245 pounds.
The price of a EcoPower unit for a PT6 is about $100,000, said Nowicki. The first unit built is the one on display here at the convention and Vector-Hawk plans to demonstrate it on actual airplanes after NBAA at an airport in the Las Vegas area. The second example is under construction, and future units will be built to order.