SpaceX drops plans for propulsive Dragon landings

GW Johnson · 2017-07-26 11:54:08

Spacenut:

I've got a long history of looking at Mars landings. I got my atmosphere data and a lot of EDL data from the big Justus & Braun report (two NASA biggies in EDL). The simplified entry ballistics is adapted directly from the old warhead stuff by H. Julian Allen in the 1950's. Such entry ballistics and exponential (scale height) atmosphere models were still taught in engineering graduate schools when I was there in the 1970's.

My list of related "exrocketman" articles follows below. I did not include the article on the old NASA Glenn Research Center Mars atmosphere model, because the Justus & Braun stuff is far, far better. This list does not include any of the expedition mission architecture designs, just the entry and landing studies I did. No artifiial gravity, space suits, or hab and suit atmospheres. I have a lot of that stuff on "exrocketman", but the topic just above is entry, descent, and landing on Mars.

GW

Mars landing articles posted at http://exrocketman.blogspot.com, site name “An Ex-rocket Man’s Take on It”. Data format: date / search keywords / title. There is a by-date-and title-tool on the left side of the page; open the year, then the month, then click on the article. Otherwise, find one with the appropriate “Mars” keyword, click that, and see only articles to search with that keyword.

“Best model atmosphere” data from Justus & Braun:

6-30-12 / Mars, space program / Atmosphere Models for Earth, Mars, and Titan

Simplified entry ballistics estimator adapted from H. Julian Allen warhead stuff:

7-14-12 / Mars, space program / “Back of the Envelope” Entry Model

1-21-13/ Mars, space program / BOE Entry Model User’s Guide

1-21-13 / Mars, space program / BOE Entry Analysis of Apollo Returning From the Moon

Typical hypersonic drag data:

8-19-12 / Mars, space program / Blunt Capsule Drag Data

8-19-12 / Mars, space program / Ballute Drag Data

Various studies done with simplified entry model and best model atmosphere data:

7-25-12 / Mars, space program / Rough Correlation of Entry Ballistic Coefficient vs. Size for “Typical” Mars Landers

8-5-12 / Mars, space program / Ballistic Entry from Low Mars Orbit

8-10-12 / Mars, space program / Big Mars Lander Entry Sensitivity Study

8-12-12 / Mars, space program / Direct-Entry Addition to Mars Entry Sensitivity Study

(Note: entry sensitivity studies established need for low path angle in entry, and that high ballistic coefficients correlate very strongly with low altitude at end of hypersonics)

8-12-12 / Mars, space program / Chemical Mars Lander Designs “Rough-Out”

8-28-12 / Mars, space program / Manned Chemical Lander Revisit

9-3-12 / Mars, space program / Using the Chemical Mars Lander Design at Mercury

12-31-12 / Mars, space program / Mars Landing Options

Final study that proved a 1-stage reusable chemical design really is feasible for Mars:

8-31-13 / Mars, space program / Reusable Chemical Mars Landing Boats Are Feasible

Last edited by GW Johnson (2017-07-26 12:01:20)

SpaceNut · 2017-07-26 16:06:13

Thanks, You sure have alot of homework reading on your site for myself and others but its worth it...

Excelsior · 2017-09-29 23:11:26

Given the new data on the BFR, I now generally agree with the decision to nix the propulsive landings, as the BFR Upper/Shuttle (we need a better name for that...) nicely fills that role, at least for manned missions. On the off chance the ISS is still there by the time the BFR flies, it can fulfill all resupply and crew transfer needs. Many times over. A far more capable replacement station, even several of them, are viable with such a launcher.

I think the Red Dragon concept still has a role to play for unmanned missions. Sending an entire BFR Upper/Shuttle to find water is a needlessly expensive gamble when you can use several Red Dragons on a single launch. Duplicate the capsules heat shield, propulsion, and landing feet on the trunk segment, and mount a rover, drill, and whatever other permanent science you want/can fit in there. Build specimen lockers into the capsule itself, with an elevator/crane that rises out of the forward hatch. Launch 6-8 of them in the bay of a Cargo BFR/Upper on that first operational launch window to shake out the system in a interplanetary transit, releasing the Red Dragons on close approach, and covering many more sites.

The Dragons would land, deploy their rovers and drills and collect their samples. The BFR/Upper would aerobrake into orbit, hopefully saving enough fuel to return to Earth. Samples would be loaded via crane through the hatch, and installed to lockers for storage. This can probably be done within a month, on a short stay plan. Once the rovers are clear, the capsules would fire their Dracos into orbit to dock in the bay of the BFR/Upper. The trunks and rovers on the ground would remain and continue observations. The BFR/Upper would fire its engines and return to Earth, probably aerobraking initially for want of landing fuel. If it really needs to land at this point, it could be refueled. In any event the Dragon capsules can be dropped for splashdown, returning a wealth of samples. Based on these results, on the next window, your full BFR landers can make their runs on the most promising targets. Further cargo and manned flights would go on the third window. In the meantime, the first round of hardware could continue making Dragon runs gradually covering more and more sites.

Such a pattern could be repeated on other terrestrial bodies. The only limit is return fuel. I think your ultimately going to see boosters modified and taken all the way to orbit and used as extra propulsion stages. Once there, they too could be refueled and used as tugs, leaving as much on board fuel for operations in theater, and for the return trip, as possible.

Last edited by Excelsior (2017-09-29 23:15:18)

louis · 2017-09-30 03:51:07

Just so everyone is clear: it is only the Dragon propulisve landings that have been abandoned, not the general use of propulsive landing both for boosters and main craft.

I think Musk has made it clear the BFR will be the first landing on Mars...he has decided to take the fast track to a Mars settlement.

I don't think it will be a needlessly expensive gamble on finding water. There are water signals over virtually the whole of Mars. The regolith itself averages 6% in vast swathes. You might note he added they wanted to land in a "dusty" place...my guess would be so they can simply scoop up the dust and warm up the ice in it and then collect and purify water in large quantities (several tonnes a day). I don't think they will need to land next to a glacier.

The great thing about the BFR is they can land with 150 tonnes of supplies on board. That is a huge amount!.

One issue though: how do they get the supplies out of the upper level of the BFR and on to the surface - must be about 70 feet off the ground? That hasn't been shown yet!

Excelsior wrote:

Given the new data on the BFR, I now generally agree with the decision to nix the propulsive landings, as the BFR Upper/Shuttle (we need a better name for that...) nicely fills that role, at least for manned missions. On the off chance the ISS is still there by the time the BFR flies, it can fulfill all resupply and crew transfer needs. Many times over. A far more capable replacement station, even several of them, are viable with such a launcher.
I think the Red Dragon concept still has a role to play for unmanned missions. Sending an entire BFR Upper/Shuttle to find water is a needlessly expensive gamble when you can use several Red Dragons on a single launch. Duplicate the capsules heat shield, propulsion, and landing feet on the trunk segment, and mount a rover, drill, and whatever other permanent science you want/can fit in there. Build specimen lockers into the capsule itself, with an elevator/crane that rises out of the forward hatch. Launch 6-8 of them in the bay of a Cargo BFR/Upper on that first operational launch window to shake out the system in a interplanetary transit, releasing the Red Dragons on close approach, and covering many more sites.
The Dragons would land, deploy their rovers and drills and collect their samples. The BFR/Upper would aerobrake into orbit, hopefully saving enough fuel to return to Earth. Samples would be loaded via crane through the hatch, and installed to lockers for storage. This can probably be done within a month, on a short stay plan. Once the rovers are clear, the capsules would fire their Dracos into orbit to dock in the bay of the BFR/Upper. The trunks and rovers on the ground would remain and continue observations. The BFR/Upper would fire its engines and return to Earth, probably aerobraking initially for want of landing fuel. If it really needs to land at this point, it could be refueled. In any event the Dragon capsules can be dropped for splashdown, returning a wealth of samples. Based on these results, on the next window, your full BFR landers can make their runs on the most promising targets. Further cargo and manned flights would go on the third window. In the meantime, the first round of hardware could continue making Dragon runs gradually covering more and more sites.
Such a pattern could be repeated on other terrestrial bodies. The only limit is return fuel. I think your ultimately going to see boosters modified and taken all the way to orbit and used as extra propulsion stages. Once there, they too could be refueled and used as tugs, leaving as much on board fuel for operations in theater, and for the return trip, as possible.

Terraformer · 2017-09-30 04:03:44

One issue though: how do they get the supplies out of the upper level of the BFR and on to the surface - must be about 70 feet off the ground? That hasn't been shown yet!

Ladders. Long ones.

louis · 2017-09-30 04:21:42

Good luck carrying down a one tonne propellant manufacturing plant, although I suppose it will only weigh 380 Kgs!

I guess we are talking about a hoist and winch. Or maybe a chute - more like those airliner chutes for getting passengers off.

Terraformer wrote:

One issue though: how do they get the supplies out of the upper level of the BFR and on to the surface - must be about 70 feet off the ground? That hasn't been shown yet!
Ladders. Long ones.

Excelsior · 2017-09-30 06:54:54

louis wrote:

One issue though: how do they get the supplies out of the upper level of the BFR and on to the surface - must be about 70 feet off the ground? That hasn't been shown yet!

That they showed it, just on the Lunar Base. They use a crane, thru the hatch about three quarters the way up. Elon was rather dismissive about it.

Which is problematic for any cargo larger than a pallet. I think the satellite deployment slide, with big clam-shell door is the key. Modify it to slide clear parallel to the tankage, and you can build a sturdier crane for bulkier items directly into the nosecone.

In the end, I think there will be a wider variety of upper stages to dispense with the 90 tons of dry mass that the shuttle brings with it. Not everything will need to interact with the atmosphere. Plus you can probably get you 12m payload back with a regular faring.

louis · 2017-09-30 08:20:35

Why do you keep calling it a shuttle?! I don't like that name!

A crane sounds doable for light loads. But surely some of the cargo would weigh tonnes...Oh well I guess if you have a crane you can maybe offload the parts to build an external lift.

Excelsior wrote:

louis wrote:
One issue though: how do they get the supplies out of the upper level of the BFR and on to the surface - must be about 70 feet off the ground? That hasn't been shown yet!
That they showed it, just on the Lunar Base. They use a crane, thru the hatch about three quarters the way up. Elon was rather dismissive about it.
Which is problematic for any cargo larger than a pallet. I think the satellite deployment slide, with big clam-shell door is the key. Modify it to slide clear parallel to the tankage, and you can build a sturdier crane for bulkier items directly into the nosecone.
In the end, I think there will be a wider variety of upper stages to dispense with the 90 tons of dry mass that the shuttle brings with it. Not everything will need to interact with the atmosphere. Plus you can probably get you 12m payload back with a regular faring.

Last edited by louis (2017-09-30 11:10:39)

GW Johnson · 2017-09-30 10:06:33

I don't know if Red Dragon will ever fly, but if it does, it is a crew Dragon with the seats and life support deleted in favor of equipment racks. They'll use the jettisoned nose cone from cargo Dragon (and delete the parachutes entirely) to lighten the landing weight, and likely use the solar wing trunk from cargo Dragon, since there is no crew abort capability needed. The crew Dragon already has the landing legs and Super Dracos. The trunk is shed prior to entry.

And by the way, there is NO possibility of ever lifting Red Dragon off again. There's only about 1200-1600 kg of propellants, and they get used to land. It IS NOT, and NEVER WAS intended to be a two-way vehicle on Mars.

Whatever it carries will have to fit through the existing hatch, and be able to deploy robotically through that opening and out onto the surface. Or else it will have to function from within the capsule's hull.

Given a tank of water to work with, you could attempt to make methane at small scale within the capsule. But that does NOTHING to address finding and processing local water.

Something that could find the water is a big robot rover with a drill rig. Something that could process the water is probably crudely the same size, but not mobile. Such stuff is unlikely to fit a Red Dragon, but could be off-loaded from the cargo BFR in spades. These would be palletized packages lowered with the crane, and assembled with a rover that has the articulated arms and manipulators to do so.

You could put together an entire subscale propellant processing plant that way, and actually demo combined LOX and LCH4 production at the 4:1 ratio actually needed. The biggest and bulkiest and heaviest item in that package is the quantity of solar panels required to power the experimental setup.

Done subscale as a feasibility pathfinder, then if successful, you bring the actual full-scale plant to the site in the subsequent 4-ship expedition, just like he showed in the IAC presentation. If not successful in robotic subscale, then you must do the 2-ship robot mission to another site first, and repeat until you do succeed.

So there, I've gone and guessed what Musk has in mind for the first missions. He's not proposing to build the base that grows to a city himself. He is proposing to provide the transportation for others to build it. So don't line up for tickets just yet. I don't yet see anyone with resources clamoring to go build that city yet. Lots of us poor folks, no rich giants yet.

GW

Last edited by GW Johnson (2017-09-30 10:15:04)

kbd512 · 2017-09-30 15:19:00

What's the major problem with putting everyone in space suits and using a minimal complexity unpressurized ascent capsule based on Dragon? The suits already have to be utterly reliable to ensure that the astronauts can perform EVA's on a routine basis. The MCP suits are clearly the way forward here. There's nothing about 1960's tech MCP suits and existing helmet technology that can't provide safe and reliable pressurization for the crew.

SOP for ascents and landings is for everyone to wear a suit. An unpressurized ascent capsule can be light enough that a comparatively nominal propellant mass is required to attain orbit or soft land. Once you get to where you're going, there has to be a "home away from home" waiting for you, or you're dead. If you can't attain orbit during ascent, you're dead. If you crater into the surface on landing, you're dead. It doesn't matter if you die in 5 minutes, 5 hours, or 50 days, you're still just as dead. There are no varying degrees of dead.

I don't see any technical advantage to these massive and overly-complicated descent and ascent systems. Obtain LOX from the atmosphere for the oxidizer and use that in conjunction with a storable chemical propellant. The same storable fuel used for ascent should also be used as a monopropellant for soft landing.

If a LOX/LCH4 plant becomes a viable replacement for existing technology after water can reliably be extracted from the surface, then a development program can be started to use those propellants for future ascent and descent vehicles. Until then, what we have works as well as it needs to work to get the job done. If giant interplanetary spaceships become viable at some point in the future, that's also great. Until then, small unpressurized capsules acting as ferries will have to suffice.

Is the goal here to simply get the job done so we can put the check in the block or is it to maintain an infinite development cycle with associated costs so high that the entire solution becomes impractical to actually use?

Absent Star Trek level technology, there will never be a "perfect" solution to the descent / ascent problem. A practical solution that doesn't require decades of development, giant interplanetary spaceships, or giant rockets is a mission enabler. That means a small, light, and simple unpressurized capsule will get the job done long before ITS and BFR ever will.

GW Johnson · 2017-09-30 16:17:36

I never said you couldn't do a small capsule as part of an ascent vehicle. I said Dragon by itself just ain't it.

There's 1200-1600 kg worth of propellants on board Dragon (either version) in tanks located between the pressure shell and the outer mold line of the capsule. Most of that gets used to land, and after dropping the trunk, which you must do to use the heat shield for entry, the mass ratio is such that you only have about 0.6-0.9 km/sec delta-vee available. The landing takes 0.5 to 0.8, as best I can figure.

There is theoretically room for more propellant in the Dragon trunk (again, either version), but only about 2900 kg worth. Figured at mass ratios reflecting trunk retention, that gives you maybe 1.5-2 km/sec delta vee, with the larger number associated with negligible payload. What is required for ascent from the surface to low Mars orbit is 3.6 km/sec as an utter minimum, with closer to 4 km/sec much more practical and safer. Plus, how do you land with the trunk in place? It has no heat shield! It just ain't there for ascending with Dragon alone, folks!

What Kbd512 envisions could be a lightweight unpressurized shell structure atop a small powered stage of the right delta-vee. This could be included as part of a larger item that lands one-way, very similar to the concept of the Apollo lander. Just remember that the delta-vee requirement for ascent (3.6 to 4 km/sec) is far larger than the delta vee requirement for landing (0.6 to 0.9 km/sec).

This is true whether you use chutes or retropulsion. Only the details vary, and really not by very much, since you come out of entry hypersonics doing roughly 0.5 to 0.7 km/sec. That's what you have to kill to land, one way or another. It's a theoretical minimum, so don't be fooled.

The higher you are at end of hypersonics, the more hover budget you need to add to that theoretical delta vee, but also the more feasible chutes become, acting to reduce it. If you come out low, there's no time for chutes, but your hover budget is also greatly reduced.

However you choose to do this, you can use storable propellants if you wish. Since the landing burn is a small portion of the total vehicle delta-vee, why take the risk of counting on ISPP for those first landings? Just use what you already know works. Switch to different vehicles later if your ISPP really pans out.

If you do a one-way descent and a one-way ascent as separate stages, the vehicle really isn't all that large. What will really drive its size is the bulk and mass of the cargo you want it to bring down. The ascent stage is actually rather small, even for a crew of 3-6.

What makes the lander a lot larger for the same payload is single-stage two-way operation: the refillable, reusable lander. That's what I put in the Mars Mission 2016 plan posted over at "exrocketman", because I wanted to visit 12+ sites. If you are set instead on visiting only one site, you don't need that. Do the smaller two-stage one-use lander.

GW

Last edited by GW Johnson (2017-09-30 16:26:12)

SpaceNut · 2017-09-30 16:36:31

Excelsior the Space x BFR is just a launcher of huge number of people or a large mass to orbit but beyond that we need more infrastructure to make it go anywhere else. Sure one big rocket is better at that then lots of smaller ones but its cost will not be all that different. Less launches means more standing army costs between the launches to keep it in top shape for use.

louis Dragons propulsive landing was only part of the issue as it could not get back to orbit even if it was fully fueled up on the mars surface that was the problem to which GW has gone over this in an earlier post. Propulsive landing on mars will not be by a capsule for a crew but more like a modified falcon first stage with a lander habitat space on the top with some where around half the fuel from the first stage landing still available for return to surface as the payload mass to the surface will lots less upon reuse. As for getting the crew down to the surface via the emergency style airliner chutes as used for getting passengers off a plane the issue is not just getting down but also getting back up...

As kbd512 points out a Dragon with crew in space suits would do for a one way lander for a crew going to a preloaded site. I am sure that GW could give us numbers on if a fully fueled with no payload could launch back to orbit or not... but gut feeling says that it would need more fuel and more thrust to make it happen.

edit I see GW gave the answer

SpaceNut · 2019-12-30 21:03:27

I am wondering if the only reason was that we could not make return fuels from mars insitu materials, that the process needed to be able to do so was not refined to be able to do so...
Of course this is the super Draco engines which for human missions still need more testing it would seem before commiting to mars.

SpaceNut · 2020-09-03 19:05:10

Yet this all you have for moon landings...
NASA selects three companies for human landing system awards]

NASA selected teams led by Blue Origin, Dynetics and SpaceX for 10-month study contracts for the Human Landing System (HLS) program. The combined value of the awards is $967 million

.

Oldfart1939 · 2020-09-04 10:01:02

In regards to the Dragon capsule, we all know it's probably a dead issue at this point. I had envisioned something of an intermediate propulsive stage inserted between the trunk and capsule itself. Enough fuel and delta V capability to land the vehicle and still assist with return to Mars orbit. Something philosophically akin to the original Atlas "Stage and a half" to orbit, where a lot of the dead weight is jettisoned after entry into Mars' atmosphere, but still retaining engines and fuel to do a short takeoff propulsive phase after the landing. I haven't done any number crunching, but this goes along with what GW says about the delta V requirements and distribution of engines and fuel.

Last edited by Oldfart1939 (2020-09-04 10:02:01)

GW Johnson · 2020-09-05 09:35:23

Landing on airless worlds has even higher delta-vee requirements than landing on worlds with atmospheres. This is true even at low gravity. That is because with an atmosphere, most of the delta-vee to land can come from entry deceleration drag. Airless, 100% of that must come from propulsion.

A design that would work on Mars will not work on Mercury, for that very reason, despite the near-equivalence of surface gravity and low orbit speeds. The moon is as hard as it is, for precisely that same reason, despite having about half the surface gravity of Mars or Mercury.

From low lunar orbit, the kinematic delta-vee for descent equals that for ascent, being around 1.6 km/s. For a two-way trip, you add them, for about 3.2 km/s. Real world, you will need maneuvering and rendezvous allowances, plus some small gravity losses. Your design must usually exceed about 3.5 km/s capability.

You have a basic choice to make: do I take this in one stage, or two? One stage confers the possibility of reusability. Two (or more) stages means it's a one-shot, throwaway design. Period. If you choose 1 stage for the reusability with chemical propulsion, you will have a very small payload fraction of initial mass. That is the tyranny of the rocket equation. Period.

If you choose 2+ stages, your payload fraction of initial mass is very much larger, reflecting the long-known advantage conferred by staging. And also inherently reflecting a one-shot, throwaway design. You would have to go to extraordinary steps to reuse anything but the final stage. Period.

As for Red Dragon, Spacex had interested a couple of the NASA labs in it, but then the NASA office running the Crew Dragon program forbade Spacex making propulsive landings on land. Crew and Red Dragon were essentially the same basic design. So when propulsive land landings (on legs) went away, so did Red Dragon.

That NASA decision has a lot more to do with (1) "not invented here", and (2) fear of doing anything not done before, than it did anything to do with engineering and technology. NASA of today bears little resemblance to the NASA of ~1960. And that is due to (1) bureaucratic stodginess that inherently results from age and size, and (2) incompetent political mis-micromanagement by Congress.

GW

Oldfart1939 · 2020-09-05 11:01:57

"That NASA decision has a lot more to do with (1) "not invented here", and (2) fear of doing anything not done before, than it did anything to do with engineering and technology. NASA of today bears little resemblance to the NASA of ~1960. And that is due to (1) bureaucratic stodginess that inherently results from age and size, and (2) incompetent political mis-micromanagement by Congress."

My recollection about the legs issue had to do with integrity of the heat shield, and the fact that Red Dragon had the legs protrude through it. It sounded more like an "excuse" at the time than a "reason." This "not invented here" mindset still pervades NASA thinking.

Bureaucracy stifles innovation. Entrenched bureaucracy kills in entirely. That's why SLS is nothing more than a failed reprise of 1960's technology.

In my post #65, my thinking was addition of an interim propulsive "throwaway" stage for landing and a short takeoff boost. Using hypergolic fuels, this would be a relatively small unit and short engineering lead time required. Something similar to one of the stages the Russians use on Proton.

Last edited by Oldfart1939 (2020-09-05 11:06:35)

kbd512 · 2020-09-05 12:21:57

Oldfart1939,

I'd agree that NIH runs rampant in NASA, but they're the ones doing most of the experimenting with new technology. They're simply very slow at applying new technology to human space flight missions, sometimes with good cause, other times not so much, unlike private companies who are not beholden to Congress. Congressional "mis-micromanagement" is not an issue with NASA, apart from them not having administrators who know how to apply the old Irish axiom of "telling Congress to go to hell in such a manner that they look forward to making the trip". They're beholden to Congress for funding and I don't know of any way around that problem for federal government agencies.

GW Johnson · 2020-09-05 16:57:37

Oldfart1939:

We have known since 1969 that you can have holes or gaps in the heatshield for hatches. The USAF did this for its MOL program re-flying a Gemini donated by NASA to USAF, leftover from one of its unmanned demo flights. This capsule flew the one and only MOL test flight unmanned, and is now in a museum. And it survived in fine shape.

It had a hatch cut right through the heat shield, to represent the Gemini-B that was to have been flown routinely in that program. As long as it is static, the gas column is such gaps or holes is actually a better insulator than the solid heat shield material adjacent to it. That's just the physics of heat transfer and compressible flow. It applies directly to the legs-through-the-heat-shield that Spacex wanted to use for Crew and Red Dragon. Same static gas column effect in a hole or gap.

My point here is a classic example of "NIH". It was USAF that demonstrated this. Not NASA. The data exist. They were just not generated by NASA.

Kbd512:

I actually see more experimentation going on with outfits like Spacex and Blue Origin than I do with NASA, in recent years. It has been some decades since NASA did real speculative experimentation. The last was the Space Shuttle, in my opinion. Which they screwed up from the 2-stage airplane that it was originally supposed to be. They did better with Apollo, but not until they reluctantly accepted the suggestion from an outsider to do lunar orbit rendezvous. THAT is how NASA got from 2 Saturn-5 shots to the moon for 1 mission, to 1 Saturn-5 shot for 1 mission.

As for NASA being micromanaged by Congress, that certainly needs to change. Congress won't change this until we vote the majority of those idiots out and replace them with new blood. Can't be done with an Executive Order.

Congress should be setting only the overall goals (like "moon landing", or "Mars landing") and overall (not detailed) budget levels. The details of exactly how to meet those goals should not be subject to the over-riding constraints of pork-barrel politics for the districts of powerful congressmen. Or to the effects of the massive pocketbooks of the giant corporations.

But I don't know how to achieve that change. And, until we do, NASA will be paralyzed by the current impasses. That leaves only the few visionary private concerns. Which is why I still think Spacex will very likely beat NASA to Mars with men.

GW

Last edited by GW Johnson (2020-09-05 17:06:06)

Oldfart1939 · 2020-09-06 11:51:31

There are undoubtedly some "bright candles" within NASA, but the overwhelming bureaucracy tends to but a damper on them. Saying that they are leading the way with research give NASA entirely too much credit. I'm sure there is more being done in some of the smaller companies than by NASA. Creative thought needs room to grow and flourish, and that's simply not the government way of doing things.

SpaceNut · 2020-09-06 13:29:06

GW Johnson wrote:

Kbd512:
I actually see more experimentation going on with outfits like Spacex and Blue Origin than I do with NASA, in recent years. It has been some decades since NASA did real speculative experimentation. The last was the Space Shuttle, in my opinion. Which they screwed up from the 2-stage airplane that it was originally supposed to be.

They we concinced that total reuseabilty would cost more.... I that that was SLI (space launch imitative) which were the 2 plane version.

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