Engine test cells are a unique blend of architecture and aerodynamics. One of the leading suppliers is Safran Aero Boosters, based in Herstal, close to Liège, Belgium, and has subsidiaries in Minneapolis, US and Singapore.

The company has its roots in Fabrique Nationale de Herstal, which began in 1949, manufacturing Rolls-Royce and General Electric engines under licence.

This become Safran Aero Boosters, specialising in low pressure compressors, with a division which specialises in the design, build, installation and commissioning of engine test cells, the associated engine-specific test equipment, and data acquisition and control systems.

This test cells activity has now been named Safran Test Cells.

It obviously has close links to Safran Aircraft Engines, especially on the CFM56 and LEAP engine programmes and, at the present moment, says Jean-Christophe Dalla Toffola, senior vice president, Safran Test Cells, the primary activity is supporting the production ramp up of the LEAP family.

This has been remarkable, he comments. The CFM 56 was launched in 1974 and there have been more than 33,000 CFM56 engines delivered to date. In comparison, LEAP was launched in 2007 with 2,000 engines to be produced this year and already 16,300 on order.

As a result, there was an initial requirement for a few facilities at various production and test locations, all of which are CFM/LEAP capable. Later, company MRO facilities Safran Aircraft Engines Mexico and Safran Aircraft Engine Services in Morocco will be added.

In response to this, the company is currently developing a standard new generation of test cells that will fit the need for LEAP next generation engines.

In response to this, the company is currently developing a new generation of standard test cells that will fit the needs of the LEAP engine. These will be available in the middle of 2019.

By using a common standard, it should be possible to reduce the length of the building time and the commissioning phase – currently every cell has to be calibrated individually.

It will also optimise the cost of operation for customers. Just as each cell will be the same physically, each will have the same operating characteristics, allowing test results to be compared and exchanged across the network and to be analysed in case of an unusual occurrence.

To ensure on time delivery, a dedicated shop has been established in Herstal to coordinate all the Test Enabling Hardware, including the thrust reverser simulator, into a complete shipset ready for dispatch.

The facilities so far are for the LEAP-1A and -1B engines for the Airbus A320 Family and Boeing 737 MAX respectively. Waiting in the wings is the LEAP-1C, for the COMAC C919. The aircraft is still in the development stage, but there will be an eventual requirement for test cells in China.

IATA agreement

In July 2018, CFM International and the IATA signed a commercial settlement agreement concerning CFM’s MRO policies and activities. Under this, CFM reaffirmed its commitment to maintain and foster robust and open competition within the MRO market, as well as the competitive nature of its MRO model.

As part of this agreement, CFM has published its Conduct Policies and associated Implementing Measures, specifying its product support policy and guidelines related to such aspects as licensing, warranties, servicing, technical support, repairs, communication, and contracting.

These documents help to confirm, clarify, and complement CFM’s aftermarket practices.

One result of the agreement, says Dalla Toffola, is that CFM/LEAP maintenance has become an even more attractive proposition, especially as GE Aviation and Safran will release more work packages, and new facilities will be built in the US.

Other engines

The company is supplying test cells for a wide range of engines, from the very large commercial engines like the GE90, to military engines.

This year, for business aircraft engines, two test cells have been delivered to GE Aviation Czech for the GE Catalyst engine, plus two for the AECC Commercial Aircraft Engine Company in Shanghai, with a further three under discussion.

The Belgian way to the Lockheed Martin F-35 Lightning II leads to a Letter of Intent from Pratt & Whitney to Safran for facilities to handle the F135.

Services

Maintenance support is another growing area. He says some facilities do not pay enough attention to routine maintenance and can be surprised by failures.

He points that the buildings take in the same volumes of air as an engine in flight, and so can be affected by the same environmental conditions – corrosion if in a coastal area, or erosion from sand ingestion, while vibrations from engines runs, particularly at lower frequencies, can cause progressive structural damage.

Any interruption can be very expensive, as engines have to be moved over greater distances to a test cell at a competitor, which is likely to demand a premium, especially if its schedule has to be amended to accommodate the displaced engine.

The company has now developed regular inspection and maintenance plans that provide a systemic approach to looking after the facility. It also has a team of 45 people spread across Herstal, Minneapolis and Singapore to provide 24/7 support. Turnover has grown by a factor of five in the last five years, and the higher demand is expected to see it triple in 2019.

Training has also become more important, and the company has developed a test cell simulator that can be adapted to different models. Just like in a full flight simulator, trainees can learn operating procedures, troubleshooting and deal with emergencies, all without live running of an engine.

This year the American branch of Safran Test Cells (former Cenco) is celebrating its 60th Anniversary, and will hold a Customer and End Users Meeting in Singapore on 11-13 March 2019.