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
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:
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 |
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.