Black Dart

The X-41 Black Dart is a futuristic military spaceplane. It is currently under development.

Features

• Main engine can gimbal from +5° to -90°, allowing hover flight in combination with a thruster in the nose.
• Nozzle extension deploys depending on thrust level (~chamber pressure) and ambient pressure, optimizing ISP.
• Nozzle performance depends on ambient and chamber pressure.
• Ladder deploys automatically when landing gear down and Ventral Bay Doors open.

Main Engine

Main engine TVC trim angle can only pass past -5°, when Main engine doors are opened. Main engine doors can only close when TVC trim angle is between +5° and -5°.

The nozzle extension position has three modes, RET, AUTO and DPY. RET keeps the nozzle in the retracted position, DPY keeps the nozzle extended.

Warning! Vertical landing with deployed nozzle extension can result in nozzle damage.

When in AUTO mode, the nozzle extension logic selects nozzle extension position for optimal ISP at current thrust level and ambient pressure. The automatic mode also retracts the nozzle when flying below 20m altitude.

Specifications (X-41A)

Empty mass	12,000 kg
Main propellant mass	10,000 kg
RCS/OMS propellant mass	6,000 kg
MTOW	32,000 kg
Main Engine Thrust (vac)	680 $kN$
Main Engine ISP (vac)	61000 ${N}\cdot {m}\cdot {kg^{-1}}$

Keyboard layout

1	Enable Low Thrust Mode of the main engine
2	Enable High Thrust Mode of the main engine
3	Toggle between OMS and main engine as main thrust group
5	Deploy antenna
6	Open/close Hatch
7	Open/Close main engine and hover doors.
8	Cycle through main engine nozzle extension modes (Retract, Automatic, Deploy)
9	Open/close canopy
0	Open/close fuel and oxidizer umbilical access doors
CTRL+0	Extend/Retract under-wing pylons.
E	Begin EVA, using the last astronaut which entered the spacecraft.
G	Deploy/retract landing gear
K	Open/close dorsal bay doors
CTRL + K	Open/close ventral bay doors
Space	Release payload.