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tekochip
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Re: West to East in less than an hour
tekochip   8/16/2012 8:46:22 AM
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The speed hasn't improved but there have been improvements elsewhere.  Navigation, weather prediction, safety and on time performance have improved greatly.  The cost of travel has remained about the same, so the cost corrected for inflation is actually less.
 
As mentioned in another post, the time on the ground has really climbed.  Long security lines and long times to board and deplane because there is way too much carry on luggage and everyone is trying to squeeze their three bags in ahead of the next guy.  The last few trips I've flown myself in my 40 year old 172, which is much slower than a 737 but without all the time on the ground the total trip is about the same.  The total cost is actually cheaper because I'm able to bring my wife for the same cost of fuel.
 
Best of all, I have more legroom too.


Charles Murray
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Blogger
Re: West to East in less than an hour
Charles Murray   8/15/2012 7:14:34 PM
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It's interesting to see how fast aircraft technology advanced between the early years of flight and the commercial jet era. But Chuck Yeager broke the sound barrier over Edwards Air Force Base in 1947. And what has happened since? Commercial jets have been flying at top speeds of about 500-600 mph for a half-century.

Rob Spiegel
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Re: Air Travel...
Rob Spiegel   8/15/2012 6:14:32 PM
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I didn't realize the margins for airlines were so slim, Jon. But I'm not surprised. For most flights I take, the cost if roughly that same as it was in the early 1970s. Needless to say, the flight experience was much better back then.

williamlweaver
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Platinum
Re: Not the first
williamlweaver   8/15/2012 5:53:48 PM
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naperlou... If you take a look at the dimensions and the image accompanying the Wikipedia article on the X-51A Waverider, you will notice it is tiny. Even a predator drone is longer by 2-ft and has a nearly 50-ft wingspan

X-51 Length: 25 ft, Empty Weight: 4,000 lb, Wingless (but for small control fins)

By the time you fill it with fuel and basic remote control electronics and communication equipment, there is not much room for exotic auto-navigation, landing, and recovery systems.

I'm not sure of our newest Naval equipment, but locating and retreiving what amounts to a 25' metal pipe at the bottom of the ocean does appear to be money well spent on design and development. I'm also going to assume that each test article has an automatic destruct just in case other nations are interested in diving for lost treasure...

williamlweaver
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Platinum
Re: Air Travel...
williamlweaver   8/15/2012 5:38:14 PM
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[Update 8/15/2012]

U.S. military's unmanned hypersonic craft fails over Pacific

An unmanned experimental aircraft failed during an attempt to fly at six times the speed of sound in the latest setback for hypersonic flight.

The X-51A Waverider was designed to reach Mach 6, or 3,600 mph, after being dropped by a B-52 bomber off the Southern California coast on Tuesday. Engineers hoped it would sustain its top speed for five minutes, twice as long as an X-51A has gone before.

But the Air Force said Wednesday that a faulty control fin prevented it from starting its exotic scramjet engine and it was lost.

"It is unfortunate that a problem with this subsystem caused a termination before we could light the scramjet engine," Charlie Brink of the Air Force Research Laboratory at the Wright-Patterson Air Force Base in Ohio, said in a statement.

We still have a ways to go before we start to see comercial applications...

Jon Titus
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Blogger
Air Travel...
Jon Titus   8/15/2012 11:11:14 AM
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The airlines are in the business of flying planes, much like the railroads were in the business of driving trains.  The airlines don't care whether you make a flight or what happens to your bags, they just want to get your money.  There's no incentive for them to get people on or off planes quickly because they have assigned takeoff and landing slots and cannot just get everyone on board quickly and take off the way a taxi could. Likewise, the airlines have no incentive to get luggage out to fliers in a timely way. The pilots landed the plane and got it to an assigned gate, end of story.

I recently learned the airline's PROFIT on a flight amounts to the cost of one economy ticket.  So if you're on a flight with 150 people and they each pay $300 for the flight, the airline makes a profit of $300.  The rest goes to expenses.  Because the airlines run a low-margin business, fliers can expect poor service.

williamlweaver
User Rank
Platinum
Re: Who's to Blame?
williamlweaver   8/15/2012 11:02:36 AM
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I'm not an aerospace engineer but I did have the privilege of being on a design team that developed diagnostics for hypersonic tests conducted at the fabled Hanger 18 of the Air Force Research Laboratory at Wright-Patterson Air Force Base -- the one that houses the Alien Technology that we keep copying...
 
The difficulty with hypersonic speeds is that fuel/oxygen mixing and combustion at those speeds have more in common with cement mixing than the traditional jet engine problem of trying to keep a candle burning within a tornado. If the aircraft is not bringing along its own fuel and oxidant, as is the case with rocket propulsion, then the oxygen must be scooped up, mixed with fuel, and compressed before it is burned to create propulsive thrust. RAM Jets skip the traditional compression blades and use the velocity of the incoming air for compression, but ultimately slow some of the the air down to subsonic speed to mix with fuel efficiently. SCRAM jets are pushing the mixing technology so that fuel and air can be mixed at supersonic speeds. The X-51A Waverider is testing this technology. 
 
It's not a regulation, management, licencing, cost thing.  It's a lack of technology thing. Very similar to the reason why we don't have efficient solar-cell shingles on every roof --- great idea, but we are not there yet.


naperlou
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Not the first
naperlou   8/15/2012 9:19:30 AM
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Rich, this is an interesting development.  You may not recall, but the X-15 rocket plane had a maximum speed of Mach 6.72, or 4,520MPH(7,274km.h).  These planes flew from 1959 to 1970.  They were piloted, dropped from a B-52 and landed like a plane.  One interesting fact I found was that the ejection seat, which was never used, could be deployed up to Mach 4.  That would be a wild ride. 

So, why can these planes not be recovered or landed.  I wonder.  The space shuttle was basically landed automatically.  The pilot was just there to take over in case of a problem.

naperlou
User Rank
Blogger
Re: Who's to Blame?
naperlou   8/15/2012 9:09:18 AM
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Jack, in this case there is a reason for the regulation.  The sonic boom will break windows and cause lots of other problems when flown over land, unless you are at a very high altitude (think SR-71).  The military also has to be careful when doing that.  Frankly, supersonic speed is great for catching up to someone or getting away from someone  (I am thinking military jets).  On the other hand, you can't shoot or turn very tightly at supersonic speed.  For transport it would be great, but the cost is very high.  Those safety and other regulations are important in this case.

TJ McDermott
User Rank
Blogger
Where is the time wasted?
TJ McDermott   8/15/2012 1:12:36 AM
A transcontinental flight takes about five hours, wheels up to wheels down.  Five hours to go 3000 miles is not too shabby, and there's no shock wave to be of concern.

I am constantly dismayed at the amount of time it takes, when using air travel, that is not actually in the air.

The airlines tell you to arrive 75 to 90 minutes before your departure, and you could spend up to 45 minutes waiting for your luggage at the other end.  Tack on an additional 20 minutes or so taxiing to and from the gate.  Call it 2-3/4 hours going effectively ZERO miles per hour.

Your average speed for your transcontinental flight isn't 600 miles per hour, it's 387, just two thirds the real speed of the plane.

Think about it.  Sure the speed is the same as it was 40 years ago. The passenger loading process hasn't changed one bit for almost a century!  It seems insane to load everyone single file through ONE door!  The time a passenger jet spends on the ground not moving people is wasted revenue to an airline.  An airline should be able to cut the turnaround time by at least 40% if more than one door is used.  Sometimes that's done on jumbos, but it's still from ONE SIDE ONLY!

A widebody has two aisles.  Why not load from both sides of the plane?  And why not load from the rear as well?  A jumbo could effectively be loaded from a four doors on two aisles.

Even a single aisle aircraft could be loaded from front and back.  I've seen a single aisle aircraft unloaded a few times in this manner at the San Jose airport in California (Alaska Air), and that gets the plane empty fast.

Time is money.  Cut the load / unload time, and make millions.

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