Jet-Care Adds PT6 to Engine Test Portfolio

Engine condition trend monitoring specialist Jet-Care is making its gas path analysis (GPA) available to operators of Pratt & Whitney Canada’s PT6 turboprop engines. The process detects deterioration and faults in the engine core by analyzing key flight data parameters, including fuel flow, shaft speeds and gas temperatures.

In tandem with the GPA service, Jet-Care also offers an array of laboratory services; analyzing oil, chips, filter debris, fuel and hydraulic fluids. These help to provide a fuller picture of an engine’s condition (see below).

Jet-Care (Booth 3816) already offers GPA trending for the P&WC PW100 turboprop and 300, 500 series and JT15D turbofans. Also included in its GPA portfolio are Honeywell’s TFE731, ALF502, LF507 and HTF7000 engines, as well as the Williams FJ44, Rolls-Royce BR710 and GE CFE738.

“Each trend program is designed and built for a particular engine and airframe type by our in-house thermodynamicists, rather than using one system for all engine types,” explained Jet-Care sales and marketing manager Josh Wagner. “This enables us to provide a very precise trending analysis service specific to the PT6 family of engines.”

Apart from identifying potential safety risks, the main benefit of GPA to operators is the chance to identify issues early enough to reduce the resulting maintenance costs. “It could be a question of a $300 fix or a $100,000 fix instead of a $1.5 million problem,” explained Wagner. It also helps by identifying issues prior to being grounded.

“The main purpose of GPA is to identify signs of core engine distress,” he said. “This can involve identifying issues such as shroud damage, [blade] tip rubbing or even airframe issues such as bleed-air leaks.

In order to conduct meaningful and accurate assessments of engine condition trends, Jet-Care first converts the GPA data to reflect standard day operating conditions and then compares the results to a mathematical model. The company standardizes the baseline for environmental conditions to sea level, zero airspeed and 15 deg C (also known as standard day ISA conditions). Trend plots are analyzed to assess any change in the engine’s condition, and abnormal deterioration will result in an alert for the operator.

The core engine parameters measured for the GPA process include speeds (N1, N2, and so forth), fuel flow and operating temperatures. This information can be collected through electronic data capture, when available, but Jet-Care also prefers to capture data manually collected by the pilot. Increasingly, flight crews are using iPads to record and upload the data, and Jet-Care’s iECHO GPA application is a useful tool for this task. By having both sets of data (electronically and manually captured) the Jet-Care team can look out for anomalies that affect one data set and not the other. This comparison is a powerful analytical tool.

In addition to identifying engine health trends that are important to maintenance planning, GPA also reveals engine usage trends. This can be particularly helpful to fleet operators eager to identify, for instance, why some of their aircraft are being operated more efficiently than others.

In some instances, Jet-Care has helped engine manufacturers with product development work. For instance, one OEM changed a gas path component that affected performance and wanted Jet-Care analysis to demonstrate to the airframer that the change had maintained or even improved overall performance.

Specialist Testing

Jet-Care’s analysis of oil, debris, filters, fuel and hydraulic fluids is offered to address three main issues: the mechanical condition of the equipment, the condition of fluids and any contamination that might undermine performance. The tests can reveal failures in the oil-wetted system such as bearings, gears, towershaft, “mis-assembly” or other oil-wetted components.

In the case of the fluids, the laboratory teams are looking for factors that could indicate oxidation and acidity in the oil or contamination issues such incorrect oil mixes, the presence of hydraulic fluid and or fuel in the oil and unacceptable levels of particulates present in the hydraulic system. Jet-Care also analyses fuel for the presence of moisture in tanks and potentially harmful microbes. “There are about 250 types of microbe that can live in the fuel, but only a dozen of these cause issues,” Wagner told AIN. “Some types of microbe eat away at the liner of a fuel tank and that can result in very expensive repair work.”

According to Wagner, what sets Jet-Care apart on the market for engine condition trend monitoring is that its testing and data analysis is so comprehensive. It also maintains a high rate of reinvestment in its capabilities, striving to identify new types of analysis to support operators and buying the equipment and investing in the training necessary to deliver these services. For instance, last year it introduced new tests to assess the cleanliness of hydraulic fluids, having spent two-and-a-half years devising ways to extract and categorize particles to assess their origins and advise operators on what follow-up may be required.

Jet-Care’s U.S. laboratory is located near Morristown, N.J., and its European sister company Spectro has facilities in the UK and Switzerland. The company is set to roll out its new webECHO online portal at this year’s NBAA show. The site allows customers to register aircraft and engines and other monitored equipment, view test results and see trend data. Its website also hosts an online discussion forum for operators.