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Before I make my engineering and science comments; SpaceNut: shouldn't this discussion be moved to a Mars thread, as inflatables for Mars entry need to be on a Mars thread? Feel free to delete this portion of this post, need arising.
What's really obvious underlying these discussions is just how poorly engineers have done w/r the Orion capsule. It is too limited in scope to be useful for anything other than just a joy ride in space. Terribly overweight and over budget. It reminds me of the old joke here in the west: a camel is a horse designed by a committee; modified form pertaining to Orion: An elephant is a racehorse designed by NASA engineers.
Even with the undeniably hefty chunk of change these guys are going to pony up for the ride, SpaceX is underwriting the bill for quite a bit of dough. I suspect this will expend all components of the Falcon Heavy, unless the 2 booster stages are recovered. I don't think they can do it any other way than as a throwaway rocket mission.
GW-
Even the specter of reusability scares the s**t out of ULA! We'll see how successful SpaceX is later on in March, when they re-fly one of their boosters.
Edit: A final comment; Dr. Zubrin states in his books that the biggest product Lockheed-Martin and Boeing have to sell is OVERHEAD, in the cost-plus contracts.
Louis-
In a way, this isn't that different than the early days of aviation. The super rich in the days just after the Wrights first flew were slinging money around for airplane rides, and posting huge (for the times) cash prizes for specific accomplishments. There were prizes posted for the first flight coast to coast in the U.S. Another significant one was for the first crossing of the English Channel. The names are legend in aviation history. The Bendix Trophy, The Collier Trophy, etc. I was reading that these 2 guys are paying Musk about the same as the Russians are charging for civilian seats on their Soyuz up to the ISS, which last I read was $22 Million each. If they are charged what the NASA astronauts have to pay, that's $80 Million per each.
I was just looking at my copy of The Case for Mars, and on p.96 there's a small table of delta V'ees for various Hohmann transfer trajectories to Mars with free return.
Here's some information for departure from LEO. For ascent to LEO, the delta V is around 8.7 km/sec.
delta V (kM/s) Transit to Mars (days) Mars Aeroentry
3.34 250 Easy
5.08 180 Acceptable
6.93 140 Dangerous
For the around the Moon flight, it seems that the Falcon 9 second stage has enough to send the Dragon + pressurized trunk + some extra fuel to circumnavigate the Moon on a free return trajectory.
When I was just a kid back in 1953, it was when the first popularized space articles had been appearing in Collier's magazine, it was only 50 years since the Wright brothers started riding on, essentially, powered kites; at that time jets were coming into service that were supersonic. Only 10 years after that, men were riding rockets into LEO, and another 10 years later, men had walked on the Moon. In my college years, I was positive we'd be on Mars by 2000, and the asteroids by 2010. What went wrong? Answer: we lacked not the intelligence and science to do so--only the POLITICAL WILL to do so. No President since Kennedy has come forward with SCIENCE and SPACE as high national priorities. Maybe--just maybe--this new one will have a different perspective. I'm not "counting on it," but...hoping!
The September 25, 2016 test was conducted using a 1/3 scale Raptor engine, but it still outperformed the current Merlin D.
rdierking-
I'm not being deliberately negative, but living in what's called "the oil patch" states, I've seen what it takes to drill a meaningful "hole in the ground." Core drilling units are smaller, as are water well drilling rigs. We just don't have the payload capacity at this point in time to get the job done. A serious rig could weigh in at least 5 tons, if not double that. Doing that sort of drilling also requires water, and lots of it. That makes 2 things we can't get to Mars that soon. Scientifically, I'd love to see several hundred linear feet of Martian core samples placed in the hands of a good geologist. In a well equipped laboratory, and not have the dregs tossed into a 250 gram sample return mission.
Here's the link to spaceflight101:
Bam! NASA just got a wake up call! SpaceX is a giant which is not sleeping. Will this force NASA into sending a crew around the Moon on the first SLS flight?
An update on spaceflight101 indicated the charges would be similar to a Russian Soyuz seat to the ISS. My last recollection was they charged a private individual something like $20 Million, but I've seen NASA quoting $80 Million to fly on a Soyuz. This might make 2018 one exciting year to be alive!
I also looked into using the Russian Proton M third stage, since it could be boosted into LEO by Falcon Heavy in the presently as designed configuration. It is NTO/ADMH fueled but there isn't enough fuel available for a TMI. The Isp is fine, but the amount of fuel comes up way short. I didn't do the calculations for staging 2 of them in sequence, however.
GW-
My calculations were for a delta V of 4.0 km/sec departing LEO; there's some wiggle room should a shorter time trajectory be desired. I also included a massive surplus of food and water in my Spacecraft mass. There's a full 30 month food supply calculated in case of an Earth Free return trajectory. It is doable with an RP-1 fueled rocket, but I'm worried about the RP-1 turning into a hydrocarbon equivalent of Jello. The step up to Methane helps a LOT w/r to Isp available and a much higher exhaust velocity in the Rocket Equation calculations. I should probably recalculate on the basis of a delta V of 5.0 km/sec departure, which should give a E-M transit time of 180 days, but still with a free return available. I'm just wondering what Elon Musk's next surprise will be? It would make sense to me for the heavy satellites he's contracted to place in GST for an upgraded Falcon 9 second stage in order to demonstrate the Raptor engine "in flight," and also showcase the Methyoxy fuel oxidizer couple. Your thoughts as to how much that could improve the lift of mass to LEO?
You added something in an edit while I was doing my last post. Here are the numbers I used: Base mass of the spacecraft minus fuel; includes the 35,000 kg and 6500 kg for the Falcon 9 rocket second stage dry weight. Then: 107,500 kg combined methane and LOX. Isp for CH4 (vacuum ):348 sec. A deltaV/C = 1.173; e^1.173 = 3.23 for the mass ratio (min). Mass ratio (actual) = 3.59. So...I have some wiggle room for a possible Mars landing, if not with the whole works but the crew capsule alone.
Just my humble opinion: W/r Mars, we've really reached a point of diminishing returns using robotics. Just bring back what samples we can scratch our of the surface will not conclusively confirm or deny the presence of life forms, past or present. I've had this argument with my friend at Lawrence Livermore National labs; he's a really big supporter of continued robotic exploration in place of "boots on the ground." I've simply known too many geologists who state that what we are looking to find requires a human on the scene. The $2 Billion spent on tis single aspect of MSR could go a very long way if used to fund SpaceX's attempts to land on Mars by 2025. I also believe that deep samples from core drilling are the only justifiable mission I could/would support--but it ain't happening any time soon.
Robert Zubrin does an excellent job in his second book: "Entering Space; Creating a Spacefaring Civilization." A brief discussion of principles of rocketry on pp. 35-38 shed a lot of light on things. I had a lot of math--55 years ago--mostly forgotten by now. I spent several hours last night working on several derivations of Differential equations that I couldn't solve anymore. So...thanks to Bob Zubrin, it is now making some sense. I'm also hoping for GW to take a look at my conclusions. I hope I'm correct, or not too wrong!
I've been doing calculations since yesterday evening using the so-called "Rocket equation," and have come up with what I call my initial Mars mission. This involves a much enlarged and modified Dragon 2 spacecraft, one with an integral cargo trunk section modified for pressurization and habitability, including a meal area, sleeping accommodations, and exercise equipment. Plus food storage. I've modified my architecture to a crew of 5. The dry mass of this portion of the system is ~ 35,000 kg. This is all within the ability of the Falcon heavy to make an orbital throw. This would be coupled with a 114,000 kg modified Falcon 2nd stage--modified to fuel by methylox propulsion and the new Raptor engine. Dry stage mass of 6500 kg, and 107,500 kg combined LOX and LCH4. These second stages would be equipped with extensible landing legs, similar to Falcon first stages currently in use. This system should be capable of meeting or exceeding the delta V of 4000 m/s required for trans Mars trajectory. There would be sufficient fuel remaining in order to land propulsively with considerable excess on hand. This vehicle could be refueled by ISPP and return to Earth orbit using aerobraking. This also calculates as "possible" using the Merlin engine and RP-1, but whether the RP-1 would remain fluid is highly doubtful? My other option is launching these systems 2 at a time--in parallel in order to use a tether between spacecraft and mutual generation of artificial gravity. The only real hangup now is getting the Falcon 2nd stages to LEO and subsequent docking with the spacecraft. I also propose they be capable of docking at the ISS through the standard cargo hatch; the spacecraft could be flown to orbit unmanned, and crew temporarily stationed at the ISS. It's conceivable that these second stages could be recycled in this manner and there are few if any throwaways. If sufficient fuel remains on board after LEO return, the possibility of a hypersonic retropropulsive atmosphere entry recovers these stages?
I've been mulling this over for a long time. Naturally, there would be several missions on order to accumulate the necessary base, preposition landing transponders, and transport the ISPP "factory" along with the Nuclear reactor and habitat construction materials.
I never intended this thread to become political, and just picked up the "Space President" moniker from another website--cannot remember which one anymore. It was asked in a somewhat rhetorical manner.
Encouraged by the fact that he's been in very close contact with Elon Musk. That bodes well for space enthusiasts such as those in this group. Hasn't anyone else figured it out yet? They are BOTH Wharton School of Business graduates, so maybe the "Good Old Boy" network is working in favor of space? I believe there is also the contact with Peter Thiel, another significant technology player (PayPal, and major investor in SpaceX).
As we've been discussing on another thread, NASA needs a real shakeup; get some of the "Christmas Tree Ornament" projects laid to rest. Focus. Focus. Focus!
GW-
I'd have to say that in order to have recoverable expensive assets, we initially should concentrate at the most interesting site on Mars. In that manner we can develop a complete orbital/ERV vehicle refueling center. In my above posts I'm attempting to come up with not a MINIMALIST approach, but one which can be carried out the soonest with components which may be available in our lifetimes. I firmly am convinced that we will be able to come up with something!
What's your opinion of using a Falcon 9 FT version 2nd stage as the landing, and potentially ERV power pack for a spacecraft with a mass of 30,000 kg? Especially if Musk goes to an upgrade with a single raptor engine using methylox fuels? Use a second similar module power pack for Trans Mars trajectory insertion. As it stands now, getting something that powerful into LEO seems to be out of reach unless SpaceX incorporates this same uprated module as it's second stage. Thoughts?
Robert-
Excellent response to my question/proposal!
As long as there are politicians involved, there will be "pork." Maybe this is the main reason I've become such an enthusiastic supporter of the Private Sector, i.e. Elon Musk & SpaceX.
You may be a bitter middle aged man, but it's hard to compete with a bitter OLD man such as I. I actually voted for JFK as my first time voting. This is why Robert Zubrin comes across to many as being bitter, too. It's called "frustration."
In my course of following many of the discussions on the Human Spaceflight and Interplanetary Transportation threads, I sensed an underlying rumble of discontent with the way NASA is/has been operating over the past several decades, and has become exacerbated since the retirement of the Space Shuttle.
Back when NASA was created out of NACA, it had a pretty clear mission: Manned Spaceflight. Over the subsequent years, NASA has undergone what normally happens to bureaucratic organizations: Mission Scope Creep. The organization has expanded to areas never originally envisioned by President Kennedy, but seem to consume more and more of scarcer and scarcer funding. Some measure of this scope creep is reflected in the Earth Science "mission," which was "encouraged" by the past administration to focus on "Global Warming," and led to falsification or modification of data. The other problem is aversion to risk taking, especially in light of 2 Space Shuttle disasters and the Apollo 1 accident. NASA was at it's finest during the abortive Apollo 13 near catastrophe.
The Nixon Administration is clearly culpable for the significant and underlying changes to the agency. Many claim that Nixon was increasingly risk averse when he cancelled the final 2 Apollo flights and declined to support a Mars direction, rather than a Space Truck to LEO where we've been stuck for 40+ years. My personal take is entirely political: Nixon HATED JFK, and took the opportunity to kill the landmark accomplishment of his short administration.
Comments?
Robert-
THX. I found the spaceflight101 data just before returning here to find your contribution. You are correct about the ability of the Falcon Heavy not currently having the necessary ability to orbit a fully fueled second stage as the payload; an uprated Falcon 9 as converted to the Raptor motor sounds capable of doing so, though. My thoughts ran along these lines: use a fully fueled Falcon 9-Raptor engine (Methylox fuel system) to power the EDS/MLS, equipped with extensible landing legs. That would propel my version of an expanded Dragon2 with the trunk extension converted to living quarters and supplies to Mars, with sufficient fuel to land. Also capable of being refueled by ISPP. Second thought: all it would need do is achieve LMO and meet up with a fully-fueled Proton M 3rd stage (storable propellants); do in-orbit reconfiguration and burn back to Earth. Granted, these are just some speculative ideas. We would have to send one of these 18 months ahead of the manned version in order to have ISPP, but it would be fully provisioned for a return mission. We could use the Falcon 9 2nd stage to boost the Proton 3rd stages to LMO and stockpile several of them there.
Here's a link to the proposed manned EM-1 Mission option.
Last night I tried to find some hard data on the total fueled mass of the Falcon 9 FT second stage, but was unable to do so. I was wanting to make a comparison to the Proton M third propulsive stage in order to do some modeling of a Mars departure stage up to Low Mars Orbit. My question was whether the Falcon Heavy could send a fully fueled Falcon 9 second stage into LEO?
Some idle speculation here: should Musk wish to test his new raptor Vacuum engine in true vacuum, maybe he's planning a possible performance upgrade to the Falcon Heavy system through incorporation of a Raptor powered 2nd stage? There's a significant performance boost available through the difference in Isp and engine thrust developed. That would achieve 2 goals: improved mass to orbit, and "proof of concept" for the Methylox system.
rdierking-
Thanks for posting a new topic, one which is sure to be somewhat controversial. I'll begin by stating my position (opinion!) regards the proposed Mars Sample Return Mission. This was one of the topics discussed at the last Mars Society chapter meetings in Boulder. As currently designed, it's overly complex, and with minimal scientific return for the dollars being expended by NASA. It seems that every time there's a mission, every group at NASA wants to be part of the Big Christmas Tree and hang their ornament on it. What I've seen, there are lots of samples they want to return, but keeping them separated and without cross-contamination is the real problem. And then--getting them back! The cost of this mission is going to hit $2 Billion, and sample collection and caching is going to delay things until 2022 if they don't get these problems resolved SOON! There's now talk of flying the mission minus the sample collection and return cache.
Need to be developed:
(1) Living quarters-expanded cargo trunk for Dragon 2+.
(2) Earth Departure stage, modified from Dragon trunk sections.
(3) Mars landing stage with extendable legs.
(4) Mars habitat stage, prepositioned on Mars with transponder system. Includes prefabricated "hard wall" habitat & airlocks.
(5) Earth return strategy and hardware.
(6) Sabatier and Moxie reaction units and storage technology for products.
After looking around a bit, it occurred to me we don't really have to do that much re: EDS and a Mars LS. The Russian Proton M uses Asymmetrical Dimethyl Hydrazine and NTO as propellants. We don't need the first stage due to having Falcon Heavy, but the second and third stages could be suitably modified by SpaceX into an EDS and MLS, or simply by purchasing the motors and adapting to the Dragon 2 Cargo trunks.
This kinda' accomplishes "getting there," so all we need now is a Earth departure stage fuelled by ISPP.
