Microturbo TRS 18

The Microturbo TRS 18 is a small, low thrust turbojet designed and built in France in the 1970s. It was installed on both manned and unmanned aircraft.

TRS 18
Type	Turbojet
National origin	France
Manufacturer	Microturbo SA

Design and development

The TRS 18 was originally designed for self-launching motor gliders but was adapted to power conventional ultralight aircraft and unmanned vehicles (RPV). It was originally designed and developed by Sermel, a competitor company to Microturbo which the latter took over in 1971.^[1] It is a simple, low thrust, reverse flow single shaft engine with a centrifugal compressor and axial turbine. It is built in three modules: an intake section containing starter and lubrication systems; a centre section with compressor and turbine on ball bearings; and an aft section with the folded combustion chambers and tail-pipe.^[2]

It gained its US Federal Aviation Administration type certificate in May 1976.^[2]

Variants

Data from Jane's All the World's Aircraft 1984-85^[2]

TRS 18-046

Production version, primarily intended for manned applications with full self start provision, oil lubrication and temperature and pressure transducers.

TRS 18-056

Cut down gas generator or core engine version, fuel lubricated and only 62% the weight of the 18-046 version but the same thrust; intended for RPVs.

TRS 18-075

Intended respectively for the Flight Refuelling ASAT target drone. Includes an engine driven alternator and fuel and oil lubrication pumps. Dry weight as 18-046. Take-off thrust increased to 1.15 kN (260 lb st) and maximum continuous thrust to 1.10 kN (247 lb st).

TRS 18-076

Intended for the Meteor-Mirach 100. Includes an engine driven alternator and fuel and oil lubrication pumps. Dry weight as 18-046. Take-off thrust increased to 1.15 kN (260 lb st) and maximum continuous thrust to 1.10 kN (247 lb st).

Applications

Data from Jane's All the World's Aircraft 1984-85^[2]

Manned

• Bede BD-5J
• Caproni Vizzola A-21SJ
• Chagnes Microstar (version of Rutan VariViggen)
• EFF Prometheus 19
• EFF Prometheus 12
• Microjet 200
• NASA AD-1 slew wing

Unmanned

• Flight Refuelling ASAT
• France-engins Mitsoubac
• Meteor-Mirach 100

Specifications (TRS 18-046)

Data from Jane's All the World's Aircraft 1984-85^[2]

General characteristics

• Type: Single shaft centrifugal turbojet.
• Length: 650 mm (25.59 in)
• Diameter: 325 mm (12.80 in) wide × 350 mm (13.78 in) high.
• Dry weight: 37 kg (81.6 lb) dry, basic, no jet pipe.

Components

• Compressor: Centrifugal; one piece with diffuser and straightener vanes.
• Combustors: Folded, with ten spill type burners.
• Turbine: Axial.
• Fuel type: Electric pump.
• Oil system: Submerged pump in tank on front underside; filter and pressure transducer on upper side. Closed circuit with high pressure supply to rotor and gearbox bearings.

Performance

• Maximum thrust: Take-off 1.10 kN (247 lb st). Maximum continuous 1.00 kN (225 lb st).
• Specific fuel consumption: 35 g/(kN⋅s) (1.24 lb/h⋅lb st).
• Thrust-to-weight ratio: 3.0

References

1. "Turbine engines of the World - Microturbo". Flight. Vol. 105, no. 3383. 10 January 1974. p. 49.
2. Taylor, John W. R. (1984). Jane's All the World's Aircraft 1984-1985. London: Jane's Publishing Co. p. 811. ISBN 0710608012.