The Delta-glider is equipped with two scramjet engines located at the underside of the fuselage which can be used during the atmospheric phase of Earth ascents/descents to preserve propellant for the primary engine system.
To provide sufficient compression of the airstream in the diffusor, the scramjets should only be operated at velocities M > 3.0. Takeoff and initial climb phase therefore require the use of the DG main engines.
Parameter | Flight model | |
---|---|---|
easy | complex | |
Intake area | 2 x 1.0 m2 | 2 x 1.0 m2 |
Burner temperature limit | 3500 K | 3200 K |
Propellant | Hydrocarbon[1] | Hydrocarbon[2] |
Fuel heating value (in air) | 3.5·108J/kg | 2.0·108J/kg |
Fuel pump capacity | 2.0 kg/s (max) | 3.0 kg/s (max) |
Thrust rating (v=Mach 4, alt=10km) | 390 kN per engine | 340 kN per engine |
TSFC (v=Mach 4, alt=10km) | 0.0051 kg kN-1 s-1 | 0.0088 kg kN-1 s-1 |
Fuel capacity | 4.0·103 kg[3] 10.4·103 kg[4] |
4.0·103 kg[3] 10.4·103 kg[4] |
Operational speed | Mach 3.0 ≤ v ≤ Mach 7.3 | Mach 3.0 ≤ v ≤ Mach 7.3 |
Operational altitude | 10 km ≤ h ≤ 40 km | 10 km ≤ h ≤ 40 km |
Sustained speed (level flight) | Mach 4.3 (alt=10km) Mach 7.5 (alt=20km) |
Mach 3.9 (alt=10km) Mach 7.3 (alt=20km) |
Fig. 1: DG scramjet TSFC vs. Mach number at ambient density 0.43 kg/m3 and ambient temperature 225 K (corresponding to altitude 10 km in standard atmosphere).
Fig. 3: DG scramjet single engine thrust vs. Mach number.