Many of the major evolutions in aircraft are still waiting out materials science to catch up. Almost every issue of Pop Sci comes with fantastic ideas for space-age aircraft that could conceivably be built… except we don’t have materials capable of withstanding the stresses. Those materials we do have (such as carbon nanotubes) can’t be produced in mass quantities at anything resembling an affordable price.
Also, I’m not sure I agree with the premise that our cars are much more advanced than they were a few decades ago. They are incrementally shaving off MPG, we’ve made some changes in crash design, and I can play my iPod through the car stereo. But at the end of the day it’s still a metal shell with a combustion gasoline engine sitting on four rubber tires. It still throws toxic gases out the pipe in the back, and the rubber in the tires still rubs off and enters the environment. They are more efficient, to be sure, but the fundamentals and the associated problems have not changed.
All the identification in the world would not stop a person who normally wouldn’t blow a plane up from blowing a plane up if they suddenly felt they had cause to. Not everybody is a Unibomber or member of a terrorist organization, anybody can decide to commit an act of violence [or have a sudden mental issue that makes them decide they need to blow something up.]
I have never had the urge to blow up an airplane, though I am sure that under the right circumstances the act may seem desirable.
Emissions from a late-model car are orders of magnitude smaller than they were from a 1960’s car with a carburetor and no exhaust cat.
“Some changes in crash design” is also a gross understatement. For its 50th anniversary, the Insurance Institute for Highway Safety pitted a 1959 Chevy Bel Air against a 2009 Chevy Malibu in an “offset frontal collision” (i.e. one vehicle or another crossed the centerline of the road) to show how far crash safety technology has come. Here’s the video; the Malibu driver might have hurt his foot, but the Bel Air driver would have been turned into hamburger.
When you’re moving around things that are massless, like bits of information, it’s possible to achieve exponential growth in your ability to move them. Pack more angels on the head of that pin.
When you’re picking up a metal box and hurling it through the air at 50 to 500 miles per hour (cars and airplanes) you have to deal with real physical issues like aerodynamics, kinetic energy, momentum, metallurgy, fuel storage & delivery, not smashing your passengers into jelly, etc.
This is why cars can’t go 200mph on the highway and travel 100 miles per thimbleful of gas. It’s also why planes still go 500mph and still represent a significant expense of energy and time.
You get some improvements, better fuel economy (but not exponentially better) better comfort (sometimes) better amenities, but they’re not going to compare to improvements in computing and communication, because they don’t have the advantage of moving nothing but data.
I wonder how much car engine efficiency has improved – it’s easy to get figures in terms of MPG, but I’m more curious about thermodynamic efficiency. MPG figures have steadily improved, but weight gains would mask improvements in engine efficiency. Off the top of my head, I believe the ballpark thermal efficiency for an internal combustion engine is 20-30%, and maximum theoretical efficiency might be 40-50%. What was the typical efficiency of, say, the Chevy small-block form 1960, vs the best today?
Question for aviation dopers: do you believe that either hybrid jet/rocket engines or reliable scramjets could make a trans-atmospheric / suborbital airliner cost effective if some portion of the flight was balistic, i.e coasting with engines off outside the atmosphere, like an ICBM warhead?
In the U.S., commercial supersonic flight has been banned since the early 1970s, which is, in large part, why no U.S. airlines ever took delivery of a Concorde, and why the U.S. airliner manufacturers killed their SST projects.
The big growth in air travel in the past few decades has been in Asia, but a lot of the demand there is for carrying as many passengers as possible (rather than carrying passengers more quickly). This is why Airbus developed the A380, which can carry upwards of 800 passengers, depending on configuration.
Interesting, RF and Analog circuits have already hit the Moore’s Law barrier, and there is a lot of work on implementing Wireless Transceivers digitally in order to be able to shrink them. I was going to write a column about this until I discovered that there were lots of discussions about it 10 years ago.
As for airplanes, you can go a lot faster than passenger jets today - if you are a fighter pilot.
The number of passengers flying routes where this would be useful is fairly small, especially when you have to amortize the development cost over them. People who pay a lot today get their own little rooms and beds. Much better deal.
If it is a real emergency, and someone has to interact right away with someone on the other side of the world, telepresence will further cut the market for this.
For many shorter flights today security and check-in time is greater than travel time. If scramjet passenger have to transfer to standard aircraft to reach their final destinations, much of the advantage will be gone when compared to more or less direct flights there.
Price of economics . The concorde was too costly to stay in service and with the price of gas it would be too costly to have other concorde than can go 2 or 3 times faster.
The direction of air travel now is big air bus and this where the research and money is going. They have some really big air bus now that they never had before.
The US military is still spending money and researching faster planes and many of them can go much faster than the concorde .
20 years? No way. Something would be on the drawing board already.
50, 100 years. <WAG> I doubt. More likely we’d send 3D avatars to meet in cyber space. Unless we were going for sex. In which case, no hurry, and with body suits, we might not to even do that.
I suspect we will go faster on the way to orbit, though.
This is a huge achievement, considering how many more thousands of flights, and how many more millions of air travellers there are, today than there were decades ago.
It is. But yes, I am sure there are still plenty of engineering as well as economical challenges to be overcome before this aircraft is seen zipping through the skies-still would love to ride one some day…
Indeed. Exactly so. You can’t fight the physics of some aspects of the RF chain, and digital techniques have made a whole slew of traditionally analog steps obsolete. I think the new gains we are starting to see is progress in hybrid chips - where the competing process requirements of digital and RF integration is being bridged. We are moving towards a mobile phone on a single chip.
Yeah, their technology is intriguing, but it just barely qualifies as “on the drawing board”. Reaction Engines LTD is a private start-up with an nifty design for a combined rocket/jet engine, but no working prototypes as far as I know. Their A2 and Skylon space planes are really just concepts from “design studies”, which is engineer-speak for “formal [del]bullshit[/del] brainstorming session”. So far they’ve secured a few million in funding here and their, but while that sounds like a lot of money, it really amounts to salary and overhead for a handful of aerospace engineers.
It’d take way more than twenty years to get a working aircraft based on these technologies. Boeing or Airbus take about ten years to design a new airliner, and that’s with fairly conventional designs and loads of private and government funding.
The docent whose tour we followed in the Smithsonian Air and Space Museum last April mentioned this. He went over the aircraft from the Wright Brothers up through mid-century and then pointed out that there have really been no major widespread leaps since then. A jetliner of the 1960s is not all that much different from one today from a passenger viewpoint or in looks. That’s a simplification of course, but looking at aircraft from 1920 and 1940 hanging there in the museum, we saw his point.