DG-S Technical Specification

Scramjet Subsystem

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)
[1]) magically enhanced
[2]) enhanced
[3]) configuration A
[4]) configuration B


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.