The Jet Sustainer System

JS-MD Turbo Jet System

For most pilots it is becoming important to have the reassurance that they will be able to land back home, especially after very long flights or a fierce competition day. The JS-MD partnership boasts a modern solution for this, matching the performance of a jet engine with a high performance sailplane.

This lightweight solution of only 17kg has no noticeable increase drag or decrease in the gliding ratio, an extremely intuitive and user-friendly user interface while giving great climb or straight line performance.

With the flick of a switch, you will become a jet pilot.

The Jet system can be installed on all JS’s gliders

TECHNICAL DATA

Engine System Specifications

Engine MD-TJ42
Manufacturer
M&D Flugzeugbau GmbH
Maximum rotary speed
97000 RPM
Idle speed
30000 RPM
Thrust at maximum rotary speed
40 daN (approximate thrust)
Fuel Consumption at max thrust
77 I/h (MSL and ISA condition)
Compression ratio
1:3.8
EGT at max RPM
790°C (1472°F)
Complete system weight – no fuel
17 kg
Fuel Capacity
JS1 – 42 liters (11.1 gal US)
JS3- 22 liters (5.8 gal US)

Standard Features for your comfort

  • Single spool jet turbine
  • Two stage axial-centrifugal stator-less compressor with a compression ratio of 1:3.8
  • Cannular combustor with multiple fuel injectors and combustion zones contained within a single annulus casing
  • Glow-plug ignition system (used in start-up sequence only, ignites top combustion zone only)
  • Convergent nozzle
  • Front-mounted, direct drive electric starter motor for initial spool up
  • Fully automated digital engine control (FADEC) system operated by a single switch and digital RPM throttle control including “Full auto start mode”
  • Single ø57 mm (2-¼ inch) colour Jet Display and control Unit (JDU) for system and throttle control, displaying RPM, EGT, fuel level & flow, and battery voltage & capacity.
  • Engine and mechanical systems mounted in monocoque carbon fibre box, easily removable for maintainability.
  • Fuselage mounted fuel tanks with integral fuel quantity sensors and filters
  • Engine extension and retraction using an electrical linear actuator with mechanical sequencing to close engine bay doors in extended and retracted positions
  • On board self-contained refuelling system (battery driven) with fuel filler connector in engine box for supply

UNMATCHED

PERFORMANCE

There is no increase in workload, only a single switch and throttle dial, and there is no noticeable performance loss with the jet extended.

The efficiency of the Turbo Jet increases with altitude. With a saw tooth flying profile at an altitude of 2000m (±6560ft) a range of 240 km (149 miles) can be obtained with the JS1 and 150 km (93 miles) with the JS3.

Maximum Power is achieved in less than 40 seconds from deployment of the system.

Visit M&D’s website to view more performance data of the MD TJ-42.

Thrust and fuel consumption versus RPM

Saw-tooth flying profile

MAGNIFICENT

DESIGN

In 2007 M&D Flugzeugbau, Jonker Sailplanes’ European partners, identified the potential benefits of installing a small jet turbine sustainer in gliders but considered the range of jet turbines available for model aircraft had limitations. Such engines had not been designed from the outset to consider certification or in-flight starting. M&D decided that rather than convert a model aircraft jet turbine into a glider sustainer, it would be better to develop and certificate a new engine.

The TJ42 has a kerosene start-up (as opposed to gas start engines) which eliminates the need for separate gas canisters and long complex start-up procedures.

The engine and pylon are enclosed by cowlings manufactured from fiberglass and aluminium (or possibly stainless steel subject to clarification of certification requirements).

In 2013 the JET Engine was integrated in the JS1 as a sustainer package.
M&D was awarded Type Certification of the MDTJ-42 in December 2015 and six months after the EASA (European Aviation Safety Agency) approved the turbine, SACAA (South Africa Civil Aviation Authority) approved the amendment of the JS1 Type Certificate to include the Jet turbine. In 2017 EASA awarded Type certification to the JS-MD 1C with Jet Turbine included.