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The Future of Flight
Roland Piquepaille writes "With "High Times," the Economist delivers a very long and extremely well-documented article about the future of aviation during the next fifty years. It tells us about pilotless planes, with 32 countries currently developing more than 250 models of unmanned aerial vehicles (UAV), primarily for combat purposes. The article also looks at future civilian pilotless planes and at the future of personal aviation. But what captivated my attention in this article was the last part about future commercial supersonic and hypersonic (at least five times the speed of sound) planes. In particular, the Economist describes the HyperSoar. "The HyperSoar is a concept for a craft flying at ten times the speed of sound and able to reach any point on the globe within two hours." This overview contains more details and references about the HyperSoar which would fly from Los Angeles to New York in 35 minutes."
planes!? Where are the flying cars? I was promised flying cars!
Esoteric reference.
hmm, I thought High Times was a publication of a different sort...
Enough said.
"Eve of Destruction", it's not just for old hippies anymore...
gee, just like the pop science article i read as a kid 30 years ago...can't wait !! (maybe they will have the 100 mile per gallon carb additive to - no wait, no more carbs !!!!)
But even with that fact HyperSoar which would fly from Los Angeles to New York in 35 minutes. How long would you have to wait at the airport to get on the plane?
Get Movie Posters
The only fly in HyperSoar's ointment is that its success is highly dependent upon Hyper-X. Note how similar the designs are.
Additionally, Hyper-X is designed to use the engine block as a heatsink. It will run for a few minutes (which is all it needs to do to get up to speed) and then the engine will melt and the aircraft will splash into the Pacific. I don't think that would be a good thing for a passenger aircraft.
I've done a few tests in X-Plane and came to the conclusion that with today's rockets and advanced materials it might be fairly easy to make a suborbital plane that can go from Paris to New-York in under an hour. I've got three different designs that could do it. The one obstacle is leading edge temperature at supersonic and hypersonic speeds, but shockwave shaping and the use of cryogenic fluid (liquid hydrogen ?) like on the 70s' XB-70 Valkyrie can overcome it.
Maybe we deserve this world ?
To bad all the major airlines don't want faster planes because of the effect it would have on the schedules of flights. Faster planes have been available for years and it still takes about 4 hours between NY and LA on commercial flights. Not to mention the sonic boom of faster than sound travel not being allowed (one of the reasons the Concorde was never used across the US).
What fuels are we supposed to use for civil flight in 50 years?
Today, the commersial airlines do not pay any environmental fees whatsoever on their fuel (correct me if I am wrong - I would like to be).
The energy cost for travel by flight is much higher than for other transport methods.
I guess that especially super/hyper-sonic flight will not be considered before the environmental issues (noise, not the least) are completely resolved.
In 50 years, I hope we have airplanes fueled by hydrogen produced in nuclear facilities.
Considering it takes about 90 minutes to orbit the earth at LEO (or 45 min to go 'anywhere'), getting anywhere in 2hrs is very impressive. I wonder if it flies inverted so that its lift prevents it from entering orbit.
HyperSoar which would fly from Los Angeles to New York in 35 minutes.
...be able to claim coast-to-coast on one battery.
*coast-to-coast claim only valid when flying at over 5 times the speed of sound.
wow, I think that if this Plane is developed, we may see the beginning of cross country commutes every day, much like we see train commuters in Connecticut.
"honey, Im gonna be late for work!!! my Editor at the LA Times sad that if I was 5 minutes late again that I would be fired!!"
"ok, just make sure you get to the subway on time this time so you can catch the 6 o' clock train to JFK"
weird.
I am the Alpha and the Omega-3
Although the article did a good job of discussing flight technology, they did not say enough on the market forces that might drive different scenarios. Its not clear whether Boeing's vision of direct point-to-point travel or Airbus's visions of mass-transit hub-and-spoke will be the future of air travel. On the one hand, the decline in business travel hurts the economics of offering quick direct flights to everywhere while new technologies like free flight aid point-to-point travel. On the other hand, its not clear whether people will tolerate multiple connections and long boarding processes required for larger aircraft like the A380.
Two wrongs don't make a right, but three lefts do.
Actually, it would mean: ;)
- strong acceleration during take-off and climb
- low gravity during most of the flight, oscillating between 0.2 to 0.8 g, or maybe an alternation of weightlessness and 1g gravity. I'm sure most tourists would appreciate a free fall experience as a bonus
- strong deceleration during the whole approach
Maybe we deserve this world ?
commercial airlines have an accident rate of 0.06 crashes per million hours of flying whereas the Northrop Grumman Global Hawk UAV used by the US military has 1600 crashes per million hours of flying. This shows that the UAVs have a long way to go before we can trust our lives to this tecnology.
When they were designing the SR-71, the Skunk Works had a hell of a time designing the life support systems for the pilot-- and that's just one guy in a space suit. At Mach 3, the heat generated by air friction is sufficient that if the cockpit air conditioning system fails, he's in deep shit. If you're reading this and you think in your lifetime you're going to see passengers flying in casual clothes more than three times faster than the SR-71, you'd better think again.
Even if it does become technically feasible, so few people will be able to afford it that it would be completely impractical to try to build a passenger transportation business around it.
~Philly
There is a joke in the airline industry that the future crew of an airliner will consist of a pilot and a dog. The pilot's job is to watch all the computers, and the dog's job is to bite the pilot if he tries to touch anything.
Remarkably bad math. Escape velocity is closer to Mach 25.
Oh, and flying upside down doesn't have a magical affect on whether or not you escape or not.
As an aerospace engineer, I'm always surprised about how many things we are supposed to achieve in the next so-many-years.
People, believe me: It is _not_ going to happen. Period.
Why not?
Well first of all, aerospace as an industry is extremely conservative. Despite it's high-tech image, the facts (and my experience) show differently. Look at the shape of aircrafts for example: Essentially unchanged since the 1930s. The fuselage-wing-tail concept is still the most popular, and all the research on blended wings, canards, double-fuselage, and other stuff people have made up, have not changed a thing (try to find the book by E. Torenbeek, you'll be amazed about how rich a phantasy some people have). That is because it simply is by far the most efficient concept: it's easy to stabilize, and you can put lots of people in it. Blended wings, for example, turn out to be too thin for people to fit in for, say, an aircraft for 100 people. Also, safety is easlier to achieve, and there's lots of room for cargo/luggage and fuel. Boeing's SST and Sonic Cruiser, and even the Concorde, did not fail without a reason. The A380, the "next generation aircraft", still has the same basic design as a DC-3 had 60 years ago. Another example is materials: Aluminum is still the primary construction material. It is _very_ slowly being replaced with composites and laminates (carbon, glass fibre/epoxy, GLARE). Aircraft manufactures can't sell an aircraft until it is absolutely proven that the new aircraft is safe and maintainable and has cheap Direct Operating Costs. So they all play safe and go with trusted concepts/materials. The A380 took about US$15_billion_ to develop. You don't go gable with such amounts. You play safe.
Then there's an economic reason. Profits for airliners are extremely low: 3-5% is not unusual. In fact, very few airlines have made a net profit over the past two decades. In the USA, airlines go bankrupt every 10 years, in Europe they would not survive without government support. Investing in airlines is high risk. This automatically means that investments in aircraft manufacturers is also quite risky. So actual research development of new technologies in the aerospace industry are very low, and usually government-sponsored, related to military applications, or conducted in universities or research institures. The "time to market" of any new technology in the aerospace industry has been estimated to be about 35 years.
This is already too long a story, I could go on for pages. But realy, this kind of views on the future just makes me laugh my pants off.
L.A city centre -> L.A airport : 50 mins
L.A. ->Tokyo : 30 mins
Tokyo airport -> Tokyo city centre: 1:20h
10 ?"Hello World" life was simple then
Before someone posts about how rockets are fuel-inefficient compared to other engines, I'd like to point out that it mostly depends on the cruise speed of the aircraft.
If the plane completes the flight in ten times less time than a conventional subsonic plane, then its engines are burning fuel for ten times less time as well.
Modern high-bypass turbofan engines have a specific fuel consumption (SFC) rate around 0.5 lb of fuel per lb of thrust per hour. Current liquid fuel rockets' SFC is around 10, and solid / hybrid rockets' SFC is around 5. But the concept of "pound of thrust" evolves with speed: for example, a reciprocating engine with a propeller will give you much more (approximately four times as much) pounds of thrust than the number of HP the engine develops, _at low speeds_. At 375 mph, you get one pound of thrust per HP. And beyond, you get much less. That's why high subsonic planes use turbofans and the slower planes still use propellers.
At supersonic speeds the fuel consumption per distance covered of a turbofan engine can grow as high as 3+, but that of a rocket engine does not grow with speed, so there's a given speed beyond which rockets are more efficient than turbofans.
Maybe we deserve this world ?
"HyperSoar's trajectory follows a skipping pattern. Passengers would feel 1.5 times the force of gravity at the bottom of each skip, and weightlessness out in space. The experience would be comparable to being on a swing, although HyperSoar's motion would be 100 times slower."
Anyone else thinking about investing their life savings into sick bag companies?
I could see UAVs being used for freight long before the public will accept it for holiday flights. Also the piolts are concerned with the collision avoidance abilites of UAVs. This may mean that in the next few years we may see plans for UAV only airports near our lager cities. For this to become anywhere near reality the problems of overcrowded airlanes and over worked air-traffic control staff, need to be resolved. For tis 'free flight' needs to be adopted, it allows piolts to plot their own flight plans and then when airborne onboard computers 'project' a 300km (30 sec)'bubble' around each aircraft, and automatically resolve incursions into the 'bubble'. This method allows more direct and efficent routes to be taken by aircraft and frees up large regions of currently unused airspace. Boeing is backing this move and is also taking an intrest in personal air transport. Yes, that means a flying car.
This article sounds just like a show that was on NPR the other day http://www.sciencefriday.com/pages/2003/Dec/hour2_ 121203.html
They had 'experts' talking about why supersonic commercial flight isn't hot, explains where our personal aircraft are at, sub orbital flights, etc.
It was an interesting listen!
Sean
I missed a zero, sorry. However, I will argue your second point
Flying right side up does prevent you from falling down to earth, and flying upside down should provide downward thrust (unless you change the angle of attack of the wings). So it should allow you to go at faster than the escape velocity.
Don't waste your vote! Vote for whoever you want, unless you live in a swing state it won't matter anyways
RTFA:The g forces would vary between 1.5g and weightlessness
Technology aside (assume it will exist) the economics are going to be tough. The Concorde went under because no one wanted to pay that kind of transatlantic fare, which meant the plane was always operating in the red. Any new technology such as a 35 Min NY-LA plane would need tends to be very expensive at first, so ticket prices would be sky high. Not to mention getting something like that FAA certified to carry passengets (so it and they can be insured) would be a nightmare and very expensive. With high-speed Internet access so cheap, you can hold a LOT of video-meetings for the price of one plane ticket. Then if you really need to go in person to close the deal, you take the lowest cost flight. In fact, most employers require you take the lowest cost flight unless it would make you arrive too late. It would be very hard to justify a (guessing here) $25,000 ticket just to save 4 hours time unless someone made $6,000/hr. I can see cases where it would pay but they are not prevalent enough to subsidize the operational costs. One positive aspect is that donor organs could be shipped anywhere for transplant, versus some limits now due to flight times. That might be worth $25,000!! Of course, a Government could give the firm an operating subsidy which would help prices to be lower. If you were looking at it strictly as a free market venture you likely wouldn't make it.
Could we all spesify weather our mach numbers are at sea level or 100,000 feet or whatever, the speed of sound changes as altitude increases.
Strive to make your client happy, not necessarly give them what they ask for
Strangely enough we've been seeing similar claims for the last 50 years. Even back in the 50's, magazines such as Popular Science were informing us that "soon" we'd have rocket planes that will take us anywhere in the world in X hours (where X is very small).
Why don't we have them yet then?
Cost. Most people want to fly as cheaply as possible and aren't willing to spend an extra grand in exchange for shaving three hours off their travel time.
In addition, unlike the 50's, business people no longer need to travel everywhere to cut deals. With the advent of email, teleconferening, etc. they don't have to.
Something we geeks need to remember is that just because we can invent a cool new technology doesn't mean there will be any drive to bring it to market.
Damianio
Speaking of sick bags, they used to have one in every seat back. On my last flight I realized I haven't seen a sick back in a long time, and I fly several times a year, so I rooted around the seatback pockets in front of me and found no sick bags.
How do they handle sick bag situations now?
Then again, in my many many flights I have never seen anyone use a sick bag.
On Dec 17th, 1903, the Wright Brothers made history. Flight has come a long way in 100 years.
There doesn't seem to be any R&D towards developing unmanned targets so I'm sure there will be plenty of employment opportunities there. And with GWB as president I'm sure there will be plenty of growth in that field.
Wings and engines have not changed much in 50 years.
But... New electronics are finding their way into small planes that anyone can learn to fly.
Now GPS makes it hard to get lost. New electronic flight displays are replacing 50 year old "steam gauge" instruments.
Sooner or later, someone will perfect cheap and reliable fly by wire controls that will make small aircraft much simpler to fly and reduce training time and improve safety.
Today, personal flying is a fun way to travel. Just yesterday was a beautiful, sunny day. I flew up to New Hampshire just to enjoy the view.
On warm days, my wife likes to fly with me down to Martha's Vineyard, a small island off the coast of Massachusetts where we can land on a grass strip 50 feet from the beach. When the sun goes down, we just get back in the plane and fly home.
Flying is a very old dream. Anyone can learn to fly, but be warned, once you start, it is very addictive! Flying is not just a way to get from here to there. It is a lot of fun all by itself.
Im currently doing my masters project on the feasibility of the hypersoar concept. In a nutshell, its possible, but with some caveats. One of the main reasons you want to do a periodic trajectory is to reduce drag and heating of the aircraft. If you stay at a constant altitude, all that heat builds up and eventually melts your plane. If you skip out of the atmosphere the heat should radiate to space, reducing your total heat load. The problem comes when you come back in. You go deeper into the atmosphere at a higher temperature than you would at a constant altitute. Ultimately your total heat load is lower, but your maximum temperature is higher by about 20% (in degrees K) which is enough to require some more exotic materials. The other thing is that you require alot of lift for pulling out of the dive at the bottom of your trajectory. So you need a high L/D ratio, which for a hypersonic vehicle is about 4. So you need wings and structure to hold the wings etc. Thirdly, you need an engine with enough thrust to overcome the drag at the bottom of the dive. If your engine isnt pushing harder than the air is pushing back, you just slow down and fall to earth. If its not pushing hard enough to bring you back to your initial velocity, you cant go very far. For my preliminary vehicle design I found that a vechile of ~500 tons with a L/D of 4 needs a thrust of about 2g's or about a million newtons If your vehicle is too light, it cant push far enough into the atmosphere to generate thrust (im using an airbreathing engine) and you crash. If its too heavy you go in to far and burn up. There is a specific range of weights and engine on-off conditions that are required for a successful trajectory. I think Ive got it worked out, but I need to do some more analysis over winter break
The airplane has some interesting scaling laws. The 747, say, gets 60 seat-MPG (you probably have to look at some actual data rather than max range data because max range has reserve for headwinds, diversion to alternate airport, but the 60 seat-MPG is not far from the mark). I am guessing, but I would say a 757 may get close to 100 seat-MPG New York-LA (the 757 is a lighter plane which is lighter per passenger, carries less fuel than a trans Pacific flight, the PW 2037 is a really efficient engine). But if you operate the 757, say Minneapolis to Detroit, I would bet the fuel mileage may drop to 40-50 seat MPG because of the energy cost of climbing to cruising altitude, low-and-slow flight in the landing pattern.
From reading a trucking magazine at a truck stop, I learned that an 18-wheeler with good aerodynamic fairings and a late-model Diesel engine gets about 6 miles per gallon. If you figure 8 miles per gallon for a bus, an intercity bus can give over 300 seat-MPG. As for the train, I am willing to guess that for a transcontinental train like the Chicago-Seattle Empire Builder, what with sleeping and dining cars, U.S. standards that passenger cars be built like tanks to withstand derailments (European passenger cars are much lighter), and all of the mountain passes on the western routes, the train is probably little different than the airplane and at the 50-60 seat-MPG range.
These Diesel commuter trains where they have one locomotive pulling 6 or 7 100-passenger double-decker cars may get something in the 500-600 seat-MPG. But if you go for acceleration and frequent stops such as a subway train, or if you go for high speed, I bet your seat-MPG start working their way back to the car and airplane range.
Interesting that you should mention high-speed rail. Part of what makes my Taurus get 31 highway MPG is that I pretty much stick to 65 MPH. All those dudes passing me doing 75 or 80 are probably getting more like 25 MPG or less. I read that the highly-streamlined but quite fast TGV's are maybe a factor of 2 better than air - I am guessing maybe about 100 seat-MPG. And that 300 MPH Japanese maglev may be comparable to air, perhaps in the 40-50 seat-MPG range.
If you start going fast, think of going at airplane speed but doing it at ground level where the air is thicker. Part of how jets get their efficiency is that they fly high -- the thin air reduces the power on their turbine engines without the losses of throttling, and the thin air allows them to go fast without too much drag. They have to pay for that efficiency with a long climb to cruising altitude. Coupled with large-long range planes being heavier, there is probably a sweet spot in efficiency for perhaps a 1500-3000 mile trip.
The problem is low-altitude (approach/departure) airspace around large airports, most large airports today are near capacity. (IFR traffic, which all airline traffic is.) Free flight doesn't buy you anything for approach/departure, which is where all the delays and inefficiencies are.
You might say the advantage of "free flight" is to the pilot -- less pesky knob-twiddling as you go from segment to segment. But the computer is flying the airplane enroute regardless of whether or not they're going direct or by a published route -- the flight computers know all the routes and will fly them all automatically. A "free flight" system has to know about traffic so it can tell the autopilot to take evasive action. That stuff is really, really expensive. (Check out how much TCAS-II systems cost.) How much longer before recreational and research aviation disappears? It's already ridiculously expensive to fly. The airlines are using this as a gambit to "own the airspace" -- make other uses of aviation prohibitively expensive so it's just airline and military flying. First transponders, then Mode C, then Mode S, and now TCAS for "free flight." (Yes, this is a rant -- but it's all true.)
Unlimited growth == Cancer.
There was a Golden Age of private aviation -- perhaps the mid 1960's, when a Piper or a Cessna was competitive with a luxury car. What has happened since then is that liability insurance has driven the light plane manufacturers into the ground and priced light planes out of the market.
We can all get mad at lawyers and call for tort reform and exemptions for plane manufacturers. But flying a light plane is a much riskier activity than driving a car, and the high liability insurance making planes really expensive is society's way of saying that we place a high value on human life, or at least on human life lost in transportation accidents, and the legal system coupled to the market system has perhaps made the correct decision in trying to get people to drive rather than fly themselves.
You mention the "steam gauges" and the need for a glass cockpit in a light plane. The "steam gauges" are there because they are simple and reliable -- and perhaps safer unless there is an enormous breakthrough in light plane avionics.
The engine controls are very primitive and manual: throttle, mixture control, and in some cases, propeller speed: not much more sophisticated than a lawn mower. If you have a turbo engine, you have manual control over boost pressure and have to follow rules for both advancing and retarding the throttle so as to not ruin the engine. In the 1980's there as some attempt at modernization: Porsche came out with an engine with electronic controls and "single-lever power control." But I don't know if this changed the general market trend that light plane manufacturers went out of business or went high-end (half-million dollar plus airplanes), and the only affordable planes are the ones stamped "Experimental" (i.e. I built it myself so I can't sue anybody).
The social effect of the hyper-sonic passenger aircraft was written about by Whitley Streibler in his book "Nature's End" in 1986.
In it he describes aircraft that can get you from L.A. to India in three hours but punch holes in the local ozone layer when they leave the atmosphere. These holes cause unfiltered sunlight to shine through tiny portals onto the earth.
In his book he describes whole blocks of children playing outside getting severely sunburned to the point of third-degree burns requiring hospitalization when one of these TAV (trans-atmospheric vehicle) windows passes over a schoolyard with kids playing at recess (an American term for the period when young children in school are allowed outside to run around).
He describes hundreds of mothers demonstrating at airports in the 2020's with pictures of their burned children begging people not to use hypersonic air travel because their pleas and lawsuits against hypersonic aircraft are ignored by the authorities.
An example of the unintended consequences that often arise when the full environmental effects of disruptive technology are not taken into account by corporate engineers. This is what science fiction is best at.