Compare that to the period from 1955 - 1975. Jets entered commercial service, displacing slow and noisy gas-powered propeller planes. The Concorde made its first flight in 1969, entering service shortly after. The US had its own supersonic airliners on the drawing board. There were even proposals for hypersonic transports. We ended up getting stuck with cosmetically identical jetliners and a series of unmanned hypersonic test vehicles. Remarkable feats like SpaceShipOne are few and far between.

Aerospace technology relies on inspiration. "Because we can" used to be a large motivator. It's tough to get around economic or military reality, but at the same time it's sad to see fewer mind-blowing engineering achievements. Most of us couldn't afford a Concorde ticket, but I bet there were plenty of people who still thought it was damn cool.

The concord was fast, but speed is not everything. The reason that there were no other supersonic passenger craft is because once this particular prestige project actually started flying everyone saw what a bad idea it really was; if the plane had been built and flown by private companies it would have been retired a decade earlier. It was cramped, had abysmal fuel efficiency, and required a great deal of maintenance to keep flying. It also turned out that few people actually needed (or were willing to pay for) the speed advantage being offered.

The current advances in passenger aircraft happen in areas that are not obvious to a casual observer; more efficient engines that require less maintenance, avionics that can fly the plane themselves and fly by wire systems that reduce weight and can increase safety. A modern sedan car looks very similar to one from twenty or thirty years ago, but the modern vehicle is superior in just about every possible way, The thing that you tend to forget about all of those "mind-blowing engineering achievements" is that most of them failed to have any significant impact -- optimization to an extreme along a single performance axis is neat, but not really as useful or interesting as most people think.

Those faster planes, not to mention things like flying cars and jetpacks, are dreams from the era of (apparently) limitless cheap energy.

Passenger space ultimately depends on cheap energy too, which is why the innovation we see is in things like entertainment systems, climate control, bigger windows, reduced noise, and so on that don't require more space.

I mean, sure, people would freak about a flying reactor, if only on principle. But that sort of thing dies down with time.

/me starts hunting for weights of marine nuclear reactors

In the 1950s, both the US and USSR did some fairly extensive research into nuclear-powered aircraft, culminating in flight tests by a US NB-36H carrying an operational 3 MW air-cooled nuclear reactor and a Soviet Tu-119 with a reactor powering two of its engines. The US had progressed quite far in developing nuclear-powered engines, culminating in Heat Transfer Reactor Experiment-3 (HTRE-3), but the project was cancelled in 1961 before it could go much further, with the Soviet project being cancelled soon afterwards. [1]

The program didn't solve all the problems that nuclear-powered aircraft could case, such as escaped radiation after crashes, but it did prove that crew shielding could be done safely at a low-enough weight that the concept remained feasible.

Scientific American featured an article [2] a couple of years ago about some people's recent calls to resurrect the idea for commercial use. But the inherent safety risks remain a big issue.

It's probably an inevitable development at some point, once the core problems have been solved. And with a new generation of high-temperature reactors emerging, such as South Africa's Pebble Bed Modular Reactor, we may see reactors that are ideally suited to this sort of thing coming through.

[1]http://en.wikipedia.org/wiki/Nuclear_aircraft

[2]http://www.scientificamerican.com/article.cfm?id=nuclear-pow...

And oops ^^; should've checked for "nuclear aircraft" on wikipedia first. I dove into details without hunting for attempts first. Thanks for the summary!

Surely we can make a bigger plane, especially if the power output of these things is enough to significantly increase the power of the engines, meaning the plane won't have to be as light (I'm thinking a flying-wing plane). Though does anyone know what the approx. power of those engines might be?

[1] : http://en.wikipedia.org/wiki/Antonov_An-225 [2] : http://en.wikipedia.org/wiki/SSTAR

However, with space travel, there's a growing consensus that sending people is too impractical and, importantly, needless. We can send robots to do our job for us. Likewise, I think air travel with stagnate because air travel will become almost inconsequential for business purposes and will merely be a leisure activity where time is not of the essence.

I'm sure studies are being done in to it, but I wouldn't be surprised if advances in communications technology and work culture are starting to have strong negative effects on compulsory business travel.

That's kinda the general feeling I get when looking at anything space-oriented. Which is part of the reason I get a bit excited reading up on recent robotics & AI progress.

People need too many supporting structures to be at the forefront of space travel, methinks. Once a tech has been proven, people adopt it pretty quickly; if anything, space travel has been disproven in terms of practicality, until some major change occurs.

I was hoping they'd get the prototype flying again. It's been sitting stationary for a lot longer than the production model, but it doesn't have nearly as much wear and tear. And it is, IMO, a more significant aircraft.