Here is the more detailed general plan of the vehicle "2500".
Figure 1. General purpose lander for Mars, Moons, etc. |
It is the standard 2 stage Apollo style vehicle. The lower part is the descent part with much as possible gas resistance and the upper part is the ascent stage with somewhat aerodynamic body to help it through the gases. The total maximum mass of the configuration is 150 000 lbs and with that amount of fuel it can do the Mars landing and return to LMO (Low Mars Orbit) without any help of aerodynamic braking. It can also handle the Earth's Moon and all other objects with less gravity than Mars.
The weight of the ascent stage is 20 000 lbs with all propellant included. All stages use typical Apollo style bi propellants and rockets have the Apollo nominal specific impulses (Isp) 311 seconds.
Figure 2. The descent stage with balanced bi propellant ball tanks. Notice that there is additional room to carry cargo etc. on the center heat shield. |
The descent stage landing gear is actually a combined fuel tank, foot pad, one shot strut, and heat shield. If the landing object has gas atmosphere then the foot pad heat shields and the center heat shields are covered with ablative material .. and everything else also such that the surfaces can sustain the landing. At touch down the foot pad heat shield works as a foot pad and the one time struts take the landing impact energies .. so that the touch down is as smooth as possible. The final (if not the whole) phase of the landing is powered as with Apollo flights and the descent rocket does most of the braking and hovering work. It is flown like a helicopter to the desired point (automatically or manually).
Figure 3. The ascent stage is rather nominal type rocekt. |
Some effort is seen to give the pilots much as possible visibility to the landing spot as early as possible. The overall planning of the landing trajectory is done so that the required flight attitude is reached at right time so that the pilots can see the landing area (as in Apollo LM landings).
The egress hatch is under the pilots flight positions and the lower part of the stage is not pressurized. The ladder slides down and the door opens to make the exit and entry possible for the astronauts. The fuels are located in the C.G. to keep the vehicle C.G. centered regardless of the amounts of propellants.
We will later return to this vehicle when doing some landing simulations with it.
* * *
No comments:
Post a Comment