Has anybody noticed that NASA has sent men nowhere off-world to explore, in over 4 decades? NASA is about much more than manned spaceflight, but that is its “front-burner” mission, its reason-for-being, and has been, since it was created in 1958.
NASA was originally formed to put man in orbit, and carry out science and aeronautics, too. But the “prime show” or “front-burner project” was manned spaceflight. 3 years later, that mission got upgraded to the far more demanding man-on-the-moon, which really energized the little agency.
In those days, NASA was rather small, very heavy on engineering talent, had a definite front-burner mission, money was no object, and no one told them how to do their jobs. They got to figure that all out themselves. And, miss-steps notwithstanding, it worked quite well. It was only 8 years from assigning the moon-as-mission to the agency, until two men first walked there.
It might have taken perhaps 5 extra years to do this, had budgets been a problem, but that basic approach of assigning the mission and then “stand back and let them do it” works really well either way.
In those days, there were dozens of prime contractors to let contracts to, competitively. Cost-plus is quite appropriate when doing things never before done. Fixed-price would have been egregious mismanagement.
All that changed in the middle of the moon landings in 1972 (there should have been missions through Apollo 22, not 17), when Apollo got cancelled early and all manned flight outside Earth orbit forbidden by presidential order. NASA has never had a front-burner mission, an agency reason-to-be, ever since. They have only had major projects mandated upon them mostly by Congress, with some from the various presidents. Projects like Space Shuttle, like ISS, like X-30, like X-33, etc.
Science and aeronautics are still small-time background, but by dint of the successes of the probes (which derives mostly from being left alone by Congress), the planetary probe program kind-of falls in-between, in that spectrum. Some of these projects, like the Mars landers and Hubble, turn out to be quite popular with the public, too popular to kill, even though Congress often tries.
Two of these mandated projects flew men in space (Shuttle and ISS), the rest didn’t. There were some tests (like X-43A) that never led anywhere. But, none of these were actually managed in an overall sense by the agency. Instead, the project, its detailed objectives, how it would be done, and where things would be built (by that I mean in whose districts) were all mandated by Congress. That’s exactly what Constellation was, and what its resurrected form Orion/SLS is. There is no one in Congress at all competent to do any of this work, which is precisely why their mandated project plans are so egregiously ineffective and nonsensical.
Meanwhile the agency has grown to enormous size, trying to be “everything to everybody” in lieu of a front-burner mission / reason-to-be. Once an organization gets too large, it gets very inefficient, worrying more about preserving departments, people, and budgets than actually doing anything real anymore. NASA is no exception. There’s more managers and support functions at NASA these days than there are real engineers. That’s not a good recipe to get anything major, actually done. Not in industry, not in government.
When you add bureaucratic inertia to mandated-but-nonsensical-projects to be done, you have what we see now: no man has flown beyond Earth orbit, or explored anything off-world, in person, since 1972. And with the mandated projects they have to do sopping-up most of the available money, we’re having a hard time not spending trillions just to go back to moon, the same moon that we visited over 4 decades ago! None of the stuff they are doing now (with the serious money) can take a crew to Mars alive, much less land there.
I’m talking about Orion/SLS as a “Mars rocket”, of course. The PR about that is nothing but lies. And everybody who knows much at all about these things knows it. Most within the agency are too afraid to “tell the emperor that he has no clothes”, though. And as an agency, NASA is afraid to tell Congress that it, too, has no clothes.
Meanwhile, Congress and the various presidents have let the available contractors "consolidate" into a monopoly supplier. With only a monopoly available, the distinction between fixed price and cost plus is functionally irrelevant. With only a monopoly available, the incentive to actually do something never done before is greatly reduced. Recently, upstarts like Spacex have attempted to break these monopolies, but with limited success. This basic situation is not NASA's fault, but their rules are rigged to favor the monopoly.
There are small groups within NASA that are working on the right kinds of things for men to go beyond Earth orbit again. But these are not funded with any serious money. Some of these groups are better managed than others. Some of these groups have better talent than others. So, their ideas and plans vary considerably in practicality and feasibility. That should not be unexpected, given the situation. But until these things get the money and attention to perfect them, they will take no one anywhere. That, you can count on.
And in conclusion, that complicated description is fundamentally why what is funded seriously at NASA often makes no sense. A lot of you may have noticed that, or at least know that something is wrong. Nothing about that situation will change, until the operating model for NASA-as-an-agency goes back to that 1958 version. They need a front burner mission as a reason-to-be, and they need to be left alone to accomplish it. Period. That mission has been known for at least 2 centuries: Mars.
Unfortunately, Congress craves ever-more control, not less. Ergo, no change is forseeable. So, no Mars.