https://arstechnica.com/science/2018/10/lockheed-martin-unveils-a-super-sized-lunar-lander-for-four-humans/This seems like a great idea, until they actually show how much it's going to cost to launch 40 tonnes of hydrolox to the Gateway for every surface sortie. Blowing a whole SLS cargo launch just to get the mostly empty lander to the Gateway is, well, rather ambitious.
Hm. It seems that someone is adapting their Kerbal spacecraft designs for actual spaceflight, if you ask me.Can someone remind them that mass still makes a difference?
Quote from: envy887 on 10/03/2018 02:19 pmhttps://arstechnica.com/science/2018/10/lockheed-martin-unveils-a-super-sized-lunar-lander-for-four-humans/This seems like a great idea, until they actually show how much it's going to cost to launch 40 tonnes of hydrolox to the Gateway for every surface sortie. Blowing a whole SLS cargo launch just to get the mostly empty lander to the Gateway is, well, rather ambitious.That is ... quite ambitious.
Quote from: speedevil on 10/03/2018 02:43 pmQuote from: envy887 on 10/03/2018 02:19 pmhttps://arstechnica.com/science/2018/10/lockheed-martin-unveils-a-super-sized-lunar-lander-for-four-humans/This seems like a great idea, until they actually show how much it's going to cost to launch 40 tonnes of hydrolox to the Gateway for every surface sortie. Blowing a whole SLS cargo launch just to get the mostly empty lander to the Gateway is, well, rather ambitious.That is ... quite ambitious.Agreed. Hard to make an exact judgement call. Slightly more sane than either Gateway or the Mars Orbiting Laboratory. I'd like more details on this lander for sure.I kind of wish Altair had been pursued instead of Orion now from the perspective that developing a lander is trickier than an orbiter but yields a more unique and usable spacecraft...as opposed to something no different than the ISS, space shuttle, or Soyuz.
If they could loss some of that dry mass and get DV upto 6km/s, would be capable of LEO -moon leg direct. Return with ISRU surface refuelling.
Two bits in the Ars story caught my eye. First off, they are saying the vehicle will be reusable for "five to 10 flights". I am by no means an engineer, but I would be a bit concerned about the actual durability of something that has such low predicted reuse (and presumably has extremely limited ability to be refurbished). I'd be dubious of doing the fourth flight of an aircraft that had "5 to 10 flights" in it. (Contrast this with SpaceX's claims for Falcon 9 Block 5 that it can potentially be flown 5 to 10 times without refurbishment, and perhaps 100 with occasional overhauls.)Second, LockMart also says that "A similar vehicle, of a similar scale, with similar engines could perform a powered landing on the Red Planet." I would really like to see more detail on that, since I would think re-entry in atmosphere would require a radically different design.
Lockheed has floated a Mars lander proposal that does use RL-10s IIRC, but otherwise is rather different.