The Turbomeca Turmo is a family of French turboshaft engines manufacturered for helicopter use. Developed from the earlier Turbomeca Artouste, later versions delivered up to 1,300 kW (1,700 shp). A turboprop version was developed for use with the Bréguet 941 transport aircraft.
Current versions are built in partnership with Rolls-Royce, and the engine is produced under licence by the Chinese Changzhou Lan Xiang Machinery Works as the WZ-6 and Romanian Turbomecanica, Bucharest, as the Turmo IV-CA.
Design and development
The Turmo was initially developed with a single-stage centrifugal compressor, annular combustion chamber and single stage turbine. Power output was from a single-stage free power turbine and was initially 200 kW (270 hp).[1]
During early post-war helicopter development, the use of cold and hot rotor tip-jets was widely investigated. To provide large mass-flow air for efficient operation of the tip-jets, Turbomeca developed a gas turbine driven gas producer, powered by the free power-turbine of the Turmo to deliver the required gas flow.[1]
Variants
Data from:-Jane's all the World's Aircraft 1957–58[1]
- Turmo I
- The initial version of the Turmo; max continuous gearbox output 200 kW (270 shp) at 3,000 rpm, at 33,750 rpm gas generator speed.
- Turmo II
- Developed version of the Turmo I; max continuous gearbox output 240 kW (320 shp) at 34,000 rpm gas generator speed.
- Turmo III
- With 2-stage free power-turbine, pressure ratio 5.7:1 ;Maximum shaft output 560 kW (750 shp), max continuous 450 kW (600 shp) at 33,400 rpm
- Turmo IIIB
- Turmo IIIC
- A 890 kW (1,200 hp) turboshaft powering the Sud-Aviation Frelon prototypes.
- Turmo IIIC2
- Developed from the IIIC delivering 970 kW (1,300 hp) maximum output
- Turmo IIIC3
- Maximum rating 1,100 kW (1,500 hp) at 33,500 rpm for production Super Frelon helicopters
- Turmo IIIC4
- Military variant.
- Turmo IIIC5
- Turmo IIIC6
- Turmo IIIC7
- Turmo IIID
- Turboprop for the proposed Breguet Br 942 STOL transport, maximum rating 913 kW (1,225 hp).
- Turmo IIID2
- 996 kW (1,335 hp) at 22,460 free turbine rpm
- Turmo IIID3
- 1,080 kW (1,450 hp) at 33,500 rpm
- Turmo IVB
- Military Variant
- Turmo IVC
- Civil Variant
- Turmo IV-CA
- Licence production in Romania
- Turmo VI
- Turboprop engine with two axial stages, one centrifugal compressor stage and two free power turbine stages, rated at 1,300 kW (1,800 hp) at 32,000 rpm.
- WZ-6
- Licence production at the Changzhou Lan Xiang Machinery Works in the People's Republic of China.
Specifications (Turmo IIIC7)
Data from Flight International.[2]
General characteristics
- Type: Two-shaft turboshaft
- Length: 182 cm (71.65 in)
- Diameter: 71.6 cm (28.19 in)
- Dry weight: 325 kg (717 lb)
Components
- Compressor: Single-stage axial, single-stage centrifugal
- Combustors: Annular, reverse-flow
- Turbine: Two-stage compressor turbine, two-stage power turbine
Performance
