moo wrote:

NERVA would do it...

The 1960s designs were at least twice as efficient as chemical rocket engines and flight designs were comparable in thrust as well.

The dry NERVA stage had about 1:1 thrust to weight. Add in reaction mass and you are nowhere near liftoff and still don't have a payload.

You could lift off from earth with an Orion style nuclear pulsedrive. But you will see oppostion well beyond the average tree hugger

nuclear lightbulb ? https://www.google.dcom/search?q=nuclear+lightbulb

I think the deep space gateway is a great concept for NASA to work towards. It would do for larger vehicles what the ISS does for orbital ones. It creates a demand for regular flights which drives down cost and increase overall capability. If you make it a true gateway able to support both exploratory and commercial missions you can start to create a real space based economy.

Some of you can't seem to think outside the box.

I grew up in the 1960s when the TV and newspapers were full of NASA performing miracles. Every day almost, some frontier was pushed back and it all grew to a crescendo that one night in 1969 when I was allowed to stay up extremely late to watch history being made.

Now, NASA has gone from breathtaking to bland. SLS? Meh. Been there, done that kind of stuff. What the politicians who are not tech minded will be saying is that NASA is reinventing old wheels and not pushing boundaries hard or fast enough, and the private sector is a better bet.

That's why I think NASA needs to be in the game of blue sky thinking. Not rocketry. Instead of chemical rockets they need to be flying test vehicles with radical new propulsion methods and funding that work appropriately. The Orion is not going to sell itself to Congress as it's rehashed technology and not nearly 'sexy' enough for the money.

Channex757 wrote:

Some of you can't seem to think outside the box.

I grew up in the 1960s when the TV and newspapers were full of NASA performing miracles. Every day almost, some frontier was pushed back and it all grew to a crescendo that one night in 1969 when I was allowed to stay up extremely late to watch history being made.

Now, NASA has gone from breathtaking to bland. SLS? Meh. Been there, done that kind of stuff. What the politicians who are not tech minded will be saying is that NASA is reinventing old wheels and not pushing boundaries hard or fast enough, and the private sector is a better bet.

That's why I think NASA needs to be in the game of blue sky thinking. Not rocketry. Instead of chemical rockets they need to be flying test vehicles with radical new propulsion methods and funding that work appropriately. The Orion is not going to sell itself to Congress as it's rehashed technology and not nearly 'sexy' enough for the money.

I a nice idea but for what goal are they pursuing what you suggest? The space program always had specific goals: Launch something into orbit, then get a human into space and then into orbit. The Saturn was developed to land a human on the moon. The space shuttle was to develop a reusable space launch system. Then there was the ballistic missile programs which also lead to satellite launch systems.

What boundaries, what specific goals are you wanting NASA to achieve? With a clearly defined goal no development will ever be completed, it will drift from one pork barrel project, to another crony company funding tool.

Tugg

Channex757 wrote:

Some of you can't seem to think outside the box.

I grew up in the 1960s when the TV and newspapers were full of NASA performing miracles. Every day almost, some frontier was pushed back and it all grew to a crescendo that one night in 1969 when I was allowed to stay up extremely late to watch history being made.

Now, NASA has gone from breathtaking to bland. SLS? Meh.

They ostracized Wernher von Braun and gained a range of dumb presidents in return.

The moon landings were driven by synergies between SPACE monomaniac von Braun and "get away from my mad generals" JFK.

After 69 NASA lost its focus and nobody was bothered because politics also lost its interest and returned to the "clowns with arms" competition.

Beyond one upping the Chinese and soaking up money from allies ( so they don't go on their own.) there is no current political interest in space.

Tugger wrote:

What boundaries, what specific goals are you wanting NASA to achieve? With a clearly defined goal no development will ever be completed, it will drift from one pork barrel project, to another crony company funding tool.

Tugg

That is what seems to be happening today.

It isn't for me to set goals. I don't have any interest in this game beyond being a spectator on a cold rock in the North Atlantic.

What I am, is a fan from the day I could read or watch a TV. I've seen NASA go from focus to drift, with no clear program that stretches them beyond their comfort zone. Apollo and Shuttle both did that. Visit the moon? Done. DC-9 size freighter to fly in space and land like a DC-9? Done. Now where is the progress towards Roddenberry's dream of a galaxy-spanning civilisation? Going faster and further all the time?

Yes you might point to SLS and Orion as going faster and further but it's not fast and furious enough. NASA needs projects where imagination is the driver; almost impossible projects that stretch science and technology as far as they can go and then a bit further. All the rest is just FedExing to orbit and it's dull.

And that is the danger. Dull isn't sexy. If it's not sexy, then politicians won't be sold on it.

DfwRevolution wrote:

SLS will have unique capabilities versus any current or soon-to-be flown booster, namely:
- Accommodation of payloads over 5 meter diameter
- Insertion of payloads between 70,000-100,000 kg to LEO
- Fast transfer of small payloads to outer solar system

All nice & well but there are no commercial applications that requires such huge payload. So what will NASA do with SLS, aside from sending Orion into deep space?

KarelXWB wrote:

DfwRevolution wrote:

SLS will have unique capabilities versus any current or soon-to-be flown booster, namely:
- Accommodation of payloads over 5 meter diameter
- Insertion of payloads between 70,000-100,000 kg to LEO
- Fast transfer of small payloads to outer solar system

All nice & well but there are no commercial applications that requires such huge payload. So what will NASA do with SLS, aside from sending Orion into deep space?

Nothing. SLS is an exploration launch vehicle only. Further, NASA hasn't been allowed to compete for commercial launch services since the Challenger disaster.

Channex757 wrote:

Some of you can't seem to think outside the box.

I grew up in the 1960s when the TV and newspapers were full of NASA performing miracles. Every day almost, some frontier was pushed back and it all grew to a crescendo that one night in 1969 when I was allowed to stay up extremely late to watch history being made.

Now, NASA has gone from breathtaking to bland. SLS? Meh. Been there, done that kind of stuff. What the politicians who are not tech minded will be saying is that NASA is reinventing old wheels and not pushing boundaries hard or fast enough, and the private sector is a better bet.

That's why I think NASA needs to be in the game of blue sky thinking. Not rocketry. Instead of chemical rockets they need to be flying test vehicles with radical new propulsion methods and funding that work appropriately.

Should Christopher Columbus have waited for the invention of jet airplanes before crossing the Atlantic? We have the technology to explore the inner solar system today. There's no reason to tinker in the laboratory with blue sky technologies that could well amount to nothing.

Channex757 wrote:

The Orion is not going to sell itself to Congress as it's rehashed technology and not nearly 'sexy' enough for the money.

Orion has already sold itself to Congress. The NASA Authorization Act passed by Congress and signed by the President in March 2017 reiterated that NASA is obligated to develop and fly Orion.

DfwRevolution wrote:

...have waited for the invention of jet airplanes before crossing the Atlantic? We have the technology to explore the inner solar system today. There's no reason to tinker in the laboratory with blue sky technologies that could well amount to nothing.

Channex757 wrote:

The Orion is not going to sell itself to Congress as it's rehashed technology and not nearly 'sexy' enough for the money.

Orion has already sold itself to Congress. The NASA Authorization Act passed by Congress and signed by the President in March 2017 reiterated that NASA is obligated to develop and fly Orion.

When did Americans stop being futurists?

In the 1950s, rocket after rocket blew up on the launchpad. Those scientists didn't complain that their tech was good enough. They took their bruises and explosions and used them as learning events.

That's why NASA needs to be pushing frontiers, not seeing what they can build behind them. Radical propulsion is the standout area they need to be working in as the civilian market will not have the focus or backing to get into those new theoretical areas and (yes...) take the failures on the chin. Finding out you have hit a dead end is not disastrous, as Feynman would have considered these "interesting". A true American genius not afraid of failure as it made success more and more likely.

Then again, we don't know just what Lockheed is hiding in the Skunk Works or out at Dugway!

I've seen comments like cancel Orion and let SpaceX take over manned space flight...

Putting into perspective - there have been at least 3 SpaceX accidents in past 5 years....

How many NASA rockets have failed on launch in past 3-5 years?

bmacleod wrote:

I've seen comments like cancel Orion and let SpaceX take over manned space flight...

Putting into perspective - there have been at least 3 SpaceX accidents in past 5 years....

How many NASA rockets have failed on launch in past 3-5 years?

But remember the perspective. NASA wasn't in early proving mode over the last 3-5 years.

Here are some links to help you look at the stats though.

http://www.spacelaunchreport.com/log2016.html



https://www.recode.net/2017/5/28/156950 ... successful

SLS has the same problem as the Saturn V and Energia. That being its lifting capacity has is way out of line with what the commercial and mundane government launches need. That results in SLS having to have unique missions designed for it resulting in very few launches and high up keep costs to maintain the system.

Meanwhile commercial and mundane government launches can use Space X rockets at roughly 6-10% of the costs of SLS. The ability to launch and save 900 million dollars is simply to great for those use that are not constrained by need to launch heavier payloads. That results in those making payloads favoring sizes that can be launched by existing affordable means. In the medium term new larger launch vehicle can arise and be successful. But they will be ones like falcon heavy that keep there costs down while targeting initial double triple launches of the existing payload sizes. Once that is established those making payloads will then be willing to upgrade the size of their payloads to use new ability given by larger launch vehicles.

In short the SLS has a chicken and eggs problem in that to be useful it has to launch larger payloads. But to launch those payloads it must be cheap enough and available in large enough quantity to cause payload designers to grow their payloads. As it stand now SLS will never achieve the cost per launch need to justify payloads being designed for it out side a very few specific ones.

That leaves you a choice do you maintain SLS at cost of manpower and brain power for those very few mission are do you let it go? I would finish development and then let it fade away. The people working on it will be better employed working on more viable long term solutions.