DGEN 380 running on the test bench at Tarnos
A Program full of maturity, youth and modernity
The objective of the DGEN program is to develop a family of two spool unmixed flow turbofan jet engines, namely DGEN 380 and DGEN 390, intended for twin engine, 2-6 seats airplanes with a max weight ranging between 1,400 and 2,150 kg (3,417 lb – 5,622 lb).
DGEN jet engines are optimized for a cruise altitude ranging from 15,000 to 20,000 ft and Mach 0.35 with a flight ceiling limited to 25,000 ft. They have low specific fuel consumption, they are lightweight and reasonably priced.
The DGEN program is directed by the engineering team of Price Induction.
Some partners assist the team on theoretical approaches and studies as well as on the methods and means to be used.
The objective is to offer a package composed of two DGEN 380 engines, their accessories and FADEC. In OEM conditions (Category A), such a package would be compatible with the appearance on the market of an aircraft with prices below $1,000,000 depending on the manufacturer and the level of equipments.
Integrating a turbine-powered engine on general aviation aircraft is a definite step forward in technology. It offers reliability, safety, automation of engine management and control, natural opening of the flight envelope and comfort, etc.
Ces images sont la propriété de GasTurb
Turbofan, a compromise between Turbojet and TurboProp.
TurbofanThe Turbofan, which is basically a ducted fan driven by a turbine, is an engine between the Turbojet, whose thrust results from hot gas ejection, and the Turboprop, that uses the gas turbine to drive a propeller. In all cases, the principle of gas generator or turbine is maintained.
The bypass ratio, defined as the ratio of cold thrust due to the action of the fan (secondary flow) to the thrust due to hot gas ejection (primary flow), varies between 5 and 9 for civil applications.
The turbofan is a very good compromise that will enable the development of airplanes with a significant potential for evolution which is precisely what an aircraft manufacturer is looking for.
The turbofan was the technological solution that allowed the development of commercial aviation in the 80’s.
TurbojetTurbojet engine’s principle is to optimize the speed and flow rate of the hot gas ejection. Thrust results from the movement of air through the gas turbine itself.
Turbojet is inappropriate for general aviation and light aviation applications. Its main default lies in its fuel consumption (SFC) that represents at least two or three times the fuel consumption of a DGEN jet engine.
The recommended ratio between thrust and airplane weight equipped with DGEN jet engines is 3. For an identical ratio, turbojet engines are heavy and too fuel consuming. Engines developing lower thrust (and therefore lower fuel consumption) allow to obtain good speeds in flight but are unable to develop enough thrust for take off (length of runway).
Moreover, because of its principle of operation, a turbojet engine is very noisy (shocked airflow at exit of tail pipe) and not adapted for low speeds.
Turbojets are usually made for military applications.
TurbopropThe kinetic energy of the hot gases is transformed into mechanical energy then used to drive the propeller. Thrust or traction results from the work of the propeller, while the residual hot thrust will be almost non existent.
The turboprop seems to be a wise choice. Compared to a turbofan, its specific consumption is slightly better. In addition the turboprop’s noise level is relatively low, it is light, and is easy to integrate in traditional airframes. In other words, it presents the advantages of using a turbine while keeping the classical presentation of a propeller.
However, despite these attractive aspects, that solution remains expensive compared to a conventional turbocharged piston engine while not providing the aircraft design potential provided by the DGEN turbofan for a PLJ.
Efficiency Performance Optimization
|PERFORMANCES||DGEN 380||DGEN 390|
|Thrust at Take Off Power (ISA-SLS, Mn 0)/SFC||255 daN||560 lb||0,44||330 daN||730 lb||0,46|
|Thrust at max cruise (ISA, FL100, Mn 0.338)/SFC||105 daN||230 lb||0,78||145 daN||320 lb||0,71|
|Flight envelope||< 25.000 ft||ISA ±30||< 25.000 ft||ISA ±30|
|< 250 KTAS||< 300 KTAS|
|Dry weight (fully equiped, without nacelle)||80 kg||175 lb||80 kg||175 lb|
DGEN performances are given as information and may change.
The DGEN jet engines are two spool, unmixed flow turbofan jet engines with a high bypass ratio. They have been designed and optimized to operate in the flight domain of traditional light aviation, i.e. below 25,000 ft and maximum speed of approximately 250/280 kts.
Fuel equipments are designed to operate with Jet A1 fuel with a specific consumption of 0.78 Kg of fuel/ Kg thrust/ hour at design point (ISA conditions , cruise setting, 10,000 ft, Mn 0.338).
DGEN engines are lubricated and oil-cooled in a closed circuit.
Each engine has its own regulation group made of a tank, heat exchanger, and pumps.
The oil tank capacity should allow operation for more than 300 hours under normal conditions.
The oil cooling system is integrated to the engine and does not require the installation of a fuel return line.
The DGEN engine uses modern and high-performance materials allowing the weight of the components to be optimized from both a structural and a functional point of view (Composites, light alloys…).
General regulation is carried out by a FADEC that controls the whole engine as well as the electric system in real time.
The management of the propulsion group (two engines) is totally under the control of the FADEC. That translates into an extreme ease of use and a much lighter workload for the pilot. Such a layout also allows a continuous engine health and usage monitoring.
FADEC and electronics are located in each engine.
DGEN engines will be presented in very integrated and complete package to facilitate aircraft manufacturing and installation.
Easy to install, Affordable, Totaly accessible ...
To complete its offer Price Induction will, in the future, offer a nacelle specially developed for DGEN engines.
1 FADEC per engine PLA
(control interface) Screen displaying