Showing posts with label Project Morpheus. Show all posts
Showing posts with label Project Morpheus. Show all posts

Thursday, January 15, 2015

NASA Technology Transfer for suborbital and air-launched orbital launchers.

Copyright 2015 Robert Clark

 I have become enamored of NASA's Morpheus lunar lander project. In the post "NASA Technology Transfer for manned BEO spaceflight", I discussed how it can be used to produce a manned lunar lander, or asteroidal lander, for a few 10's of millions of dollars, far less than the $10 billion estimated to be needed by NASA. And in "NASA Technology Transfer for Orbital Launchers", I discussed how its engines could be used for the small orbital launch system Firefly, resulting in a significant reduction in the launcher's development costs.

 I don't think NASA fully appreciates the usefulness of the Morpheus development. Here I'll show how the Morpheus itself can be used to produce suborbital launchers, and also the stages for orbital launchers. For instance the Morpheus can be used to provide the solution to DARPA's ALASA air launched, small orbital system.

 The Wikipedia page on the Morpheus gives its propellant load as 2.9 metric tons (mT) and dry mass as 1.1 mT. Its methane/LOX engine has an Isp of 321 s with a thrust of 24 kN, 2,450 kilogram-force (kgf).



 Note this means when fully fueled the single engine could not lift the vehicle in Earth's gravity. The single engine of course would be fine for its intended purpose as a lunar lander at 1/6th gravity. However, for a Earth launch system we'll use a half-size vehicle to be launchable with a single engine. Rounding off this gives it a propellant mass of 1.5 mT and dry mass of .5 mT. Compared to the full Morpheus this will have only two spherical propellant tanks instead of four, one each for the liquid methane and LOX.

 Since this will be reaching high velocity through Earth's atmosphere it will have to be streamlined. Then we'll place the two propellant tanks inline vertically. We'll also need an aeroshell. To save weight we could make the aeroshell composite. Another possibility would be to make the aeroshell inflatable. Since the aeroshell would not need to be load-bearing and with the possibility to make it inflatable we'll assume it adds only a small proportion to the weight. We could save additionally weight by making the tanks out of aluminum-lithium alloy, titanium, or composites. Alternatively, we could use a cylindrical tank to hold the propellants to eliminate the need for an aeroshell.

 Suborbital Case.

 This page gives the required delta-v for a suborbital flight as in the range of ca. 2,400 m/s:

Flight Mechanics of Manned Sub-Orbital Reusable Launch Vehicles with Recommendations for Launch and Recovery.
Mechanical and Aeronautical Engineering Department, University of California, Davis, CA 95616-5294
Marti Sarigul-Klijn Ph.D. and Nesrin Sarigul-Klijn*, Ph.D.
An approximate delta V to reach 100 km is 7,000 to 8,000 fps (2,100 to 2,400 m/s) for vertical takeoff, with slightly less delta V needed for air launch, and significantly more required for horizontal takeoff.
http://www.spacefuture.com/archive/flight_mechanics_of_manned_suborbital_reusable_launch_vehicles_with_recommendations_for_launch_and_recovery.shtml

  Now, at a 1.5 mT propellant load, .5 mT dry mass, .25 mT payload, and 321 s Isp, the vehicle can do a delta-v of 321*9.81ln(1 + 1.5/(.5 + .25)) = 3,460 m/s, sufficient for a suborbital flight.

 There are commercial opportunities for suborbital flight with NASA. Also using two to four copies or scaled up that many times this could also be used for a suborbital tourism vehicle.

DARPA Air-Launched Orbital Vehicle.

 DARPA is funding research into a small air-launched system called ALASA, As described in the blog post "Dave Masten's DARPA Spaceplane, page 2: an Air Launched System", high altitude supersonic air-launch at Mach 2 can cut 1,600 m/s from the delta-v needed for low Earth orbit. This would reduce the delta-v that needed to be supplied by the rocket from 9,100 m/s to 7,500 m/s.

 We'll use two copies of the half-size Morpheus firing in parallel and cross-feed fueling. Cross-feed fueling allows the upper stage to have its full level of fuel after staging, unlike the usual case with parallel staging. As in the earlier blog post, we'll again use the Star 17 solid stage as the final, orbital stage:

Encyclopedia Astronautica.
Star 17
Solid propellant rocket stage. Loaded/empty mass 124/14 kg. Thrust 19.60 kN. Vacuum specific impulse 280 seconds.
Cost $ : 0.580 million.
Status: Out of production.
Gross mass: 124 kg (273 lb).
Unfuelled mass: 14 kg (30 lb).
Height: 0.98 m (3.21 ft).
Diameter: 0.44 m (1.44 ft).
Span: 0.44 m (1.44 ft).
Thrust: 19.60 kN (4,406 lbf).
Specific impulse: 280 s.
Specific impulse sea level: 220 s.
Burn time: 18 s.
Number: 25 .
http://www.astronautix.com/stages/star17.htm

 Then we can get a payload of 55 kg to orbit by supersonic air-launch:

321*9.81ln(1 + 1.5/(.5 + 2.0 + .124 + .055)) + 321*9,81ln(1 + 1.5/(.5 + .124 + .055)) + 280*9.81ln(1 + .110/(.014 + .055)) = 7,690 m/s.


  Bob Clark






Saturday, January 3, 2015

NASA Technology Transfer for Orbital Launchers.

Copyright 2015 Robert Clark


 NASA's Technology Transfer Program intends to partner with U.S. companies to commercialize technology developed at NASA. One example is the autonomous landing system for robotic lunar landers (ALHAT) developed by NASA which will be used by the Moon Express team for their Google Lunar X-prize entrant. 

 I suggest another example that has more important commercialization potential are the methane engines developed for NASA's Project Morpheus robotic lunar lander. The Firefly launch company intends to make small methane fueled orbital launchers. The largest single development cost for a launcher are usually the engines. By using the engines already developed for the Morpheus lander for the Firefly, a significant proportion could be cut from the development cost.


  Bob Clark

Friday, June 13, 2014

The Morpheus lunar lander as a manned lander for the Moon.

 Copyright 2014 Robert Clark

 Nice article here on the Morpheus lunar lander:

Project Morpheus Concludes Successful Flight Test Campaign With Spectacular Night Launch.
By Mike Killian
http://www.americaspace.com/?p=61298&cpage=1


The project leader notes it could be scaled up to be a manned lander. Based on specifications of the lander I estimate it would need to be scaled up by a factor of three to form a descent stage while using the original sized version for the ascent stage. The delta-V from low lunar orbit to the lunar surface is 1,870 m/s each way:

Delta-V Budget.
Earth-Moon space.

http://en.wikipedia.org/wiki/Delta-v_budget#Earth.E2.80.93Moon_space

 According to the given specifications, the Isp of the Morpheus engine is 321 s and the propellant load is 2.9 mT and dry mass, 1.1 mT. So with a 2 mT lunar capsule mass, the ascent stage consisting of a single Morpheus would have delta-v of:

321*9.81ln(1 + 2.9/(1.1 + 2)) = 2,080 m/s.

 The descent stage consisting of the Morpheus scaled up three times would have a 8.7 mT propellant load and 3.3 mT dry  mass. Carrying the 4 mT of the ascent stage and the 2 mT capsule, the descent stage would have delta-v of:

 321*9.81ln(1 + 8.7/(3.3 + 4 +2)) = 2,080 m/s.

  Another nice article describes the origin of the idea of the Morpheus and its innovative, low cost approach:

A father-son chat leads to first-of-its-kind NASA spacecraft.
By Thom Patterson, CNN
updated 8:00 AM EDT, Mon May 19, 2014 |
http://www.cnn.com/2014/05/18/tech/big-idea-morpheus-lander/

 Based on a $14 million development cost for two prototypes, one scaled up by a factor of three might cost $21 million. So $28 million for both stages. Actually by the Wikipedia page on Project Morpheus, the parts to build the Morpheus version 1.5B were only $750,000. So construction of a single Morpheus was probably well less than $7 million, and the cost for one three-times scaled up one well less than $21 million.

  Instead of scaling up the Morpheus, we could also combine three of the original size to form the descent stage, with the same development cost of $21 million. This would have an advantage of a quicker time to producing a flight capable prototype. Another problem with the scaled up version of the descent stage is that based on the 12 foot height of the original version I estimate an 18 foot height of the descent stage. That would be a high climb down for the astronauts. Constructing the descent stage of three copies of the original-sized Morpheus though would allow you to connect them together on a single level so the climb down would still be 12 feet.

  In any case we see again, just as with the Masten Xeus lander, a manned lunar lander can be made for 10′s of millions of dollars rather than the $10 billion of the Altair lunar lander.

      Bob Clark 

Lightweight thermal protection for reentry of upper stages.

 Copyright 2025 Robert Clark   In the blog post “Reentry of orbital stages without thermal protection, Page 2”,  http://exoscientist.blogspo...