Clark Lindsey has some thoughts on the late Kistler concept, with which I largely agree:

I've never thought the K-1 design that they came up with was anywhere close to an ideal RLV. For example, it doesn't allow for incremental testing to find problems without losing the vehicle as Rutan could do with the SS1. However, it was a proof of principle that even a group of conservative NASA/Apollo/Saturn engineers could sit down and design a two-stage-to-orbit (TSTO) fully reusable vehicle without breaking any laws of physics or requiring even an ounce of unobtainium. Other than the occasional anonymous commenter posting "the K-1 is crap" sort of criticism, I've never seen any credible person point to some particular part of the K-1 design and say this definitely is not going to work.

Kistler got 75% of the hardware built for the first K-1 when their target LEO comsat constellation market disappeared and funding dried up. Kistler had at that point spent about $800M but raised only $600M. The company itself had remained relatively small and had farmed out most of the hardware to various mainstream aerospace companies. (SpaceX decided that building many of its major components in house could save lots of money over this outsourcing approach.) People who were involved with other entrepreneurial launch vehicle companies during that period occasionally express annoyance, to say the least, that Kistler Aerospace soaked up most of the private investment available for such ventures yet still didn't get anything into the air.

I always thought that it was a mistake to hire Apollo retreads for the job. George Mueller and company knew how to get the job done on an unlimited budget, but they didn't have one (though they had a lot more money than anyone else). There was never any reason to think that they could do things cost effectively. My understanding is that the investors demanded that "space experts" be brought in. Unfortunately, the "space experts" they brought in simply farmed the job out to cost-plus contractors, because that's all they knew how to do.

Whether they really "soaked up all the private money for such ventures" is hard to know, because the investors that were willing to put money into Kistler weren't necessarily willing to put money into a company that didn't have old Apollo hands running it. So perhaps that was their loss, not the industry's.

I've been running a "newspace" company since about 1992 and nothing has changed. If you go to the market for funds they inevitably turn to the "experts" - NASA etc and their retirees for an "expert" opinion. Kills most deals at that point becasue the "experts" can (a) never agree and (b) always advise extreme caution lest they be seen to have advised backing a failure. It's one more example of risk aversion in American society.

It is only the advent of entrepreneurs with money that has begun to tip the balance a little. Once someone achieves orbit, manned flight etc. and does so reliably then reliance on the old ways will decline and the investment community will begin to accept that not all space "experts" come from NASA.

Meanwhile the rest of us who do not have deep pockets soldier on keeping the dream alive and sometimes making a difference.

No offense, but risk aversion is a good thing when you don't understand the risks. In the above scenario, the potential investor asks someone else who doesn't really know what's going on either or perhaps who doesn't give a straight answer. That's a sure indication to me that the investor shouldn't be investing in New Space.

As I see it, New Space will just have to live with low investment because currently it is far too uncertain a market for rational but ignorant investors to enter. Who can you hire to soundly evaluate the risks of a New Space investment?

For example, let's just consider ten years ahead. What launch vehicles will be present and how much will they cost? What will the regulatory and insurance environments look like? Will you be able to own property in space? What customers will be present in space? Big questions and I doubt anyone knows more than a small bit of the answers.

All we know for sure is that there will continue to be demand for satellites in space, there will be some sort of government activity by multiple nations in space, economic activity on Earth will increase somewhat, and all those planets, moons, and asteroids will still be around.

No offense taken, for the average "man in the street" thiis is exactly what should happen. However, risk aversion is not necessarily a good thing in any market. There has to be some catalyst for change or we will stagnate as a nation, as a culture and as a business environment. I would suggest we cannot afford to stagnate at any level. We are already hearing about the drop in post-graduate students in science and technology. In five or so years time this will translate into a larger problem for the R&D and manufacturing companies.

There are currently two profitable sectors using space and they both rely on the ground to provide customers. Those two sectors are: (a) Communication Satellites and (b) Earth Observation satellites.

It may be argued that in both cases the mechanism by which the system works is essentially transparent to the user and largely so to the operator. This community only gets concerned when the capability no longer exists. So, to some extent we are always dealing with negative perceptions, the best we can hope fopr is to come up to the zero line from a negative value. In other words; "nobody sees us if we do our job perfectly".

In my opinion nothing is going to change significantly until we are able to move to and fro to orbit reliably and routinely with people on board. We can pretty much get to orbit reliably, it is not yet routine; but we cannot reliably bring people back to the surface on a routine basis. Niether Shuttle nor Soyuz can be considered routine.

It is for this reason that hope for the future lies with the current crop of sub-orbital vehicle developers. Roughly 32 Mj of energy per kilo of mass is imparted to a body to reach orbit and it has to be extracted from that body during re-entry and landing. Extraction of that energy has to occur in a controlled and reasonable manner - particularly if people are on board. This is the "hard" problem; it's not the only problem but it is probably the most intractable.

Company's like the Orbital Commerce Project and SFO are solving this problem incementally; starting with sub-orbital vehicles and gradually expanding the enevelope. We are currently developing vehicles that will exist in "Near" space - those altitudes between about 65000ft and 365000ft. Hopefully we will solve the "hard" problems in this flight regime.

When we show that we know what we are doing contracts will surface for all sorts of applications.

Kistler also had those initial problems of proposing the Launch Assist Platform that was supposed to hover and catch the returning booster. It took me a while to take anything they said seriously after seeing that design.

I've also had trouble with their 75% complete claims. Has anyone seen a complete (or 75% complete) stage? All I've seen are cartoon images of the system with pictures of some small hardware components inset, and computer generated images of the stages themselves. If they actually built a first or second stage, it would be something to crow about, but yet I've seen nothing.

Perhaps they mean 75% complete by mass.