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The B-52 was designed in a hotel over a weekend with sketches on the notepad in the room and calculations done on a roll of toilet paper.

I've seen designers comment on it in documentaries, but the official Boeing history of it's design weekend leaves that bit out.

http://www.boeing.com/defense-space/military/b52-strat/b52_50th/design.htm

Probably somewhere between 300-500hp. It appears to be a Boeing T50/502. Although, I wouldn't imagine it's all that fast on the 1/4 mile. Turboshaft engines are designed to operate at a constant speed and are very inefficient when used like a piston engine.

Painting a plane weighs a few hundred pounds. It does not need to be taken into consideration on a 300,000 lb plane.

They do not remove the paint if "too much accumulates" while painting. Heck, they can put two full layers on before operational efficiency is impacted.

http://www.boeing.com/commercial/aeromagazine/aero_05/textonly/fo01txt.html

Since Airbus has a better safety record, you should trust the software more.

Citation Needed

Boeing's own presentation is one source of many.

Only the 777 is on par with Airbus. And of the three safest widebodies (the 777, A330 and A340), the 777 is the only one with a hull loss due to a mechanical failure (luckily with no pax fatalities but that was luck more than anything else). Besides, anybody that thinks Boeing flies without the risk of software bugs fucking it up for pilots doesn't know how the FBW system in the 777 works (the only Boeing FBW in service). It has a control column but there's no direct pilot to hydraulics input, it's just a more intuitive interface for pilots than the side-sticks Airbus use. Software processes the pilot inputs (to various degrees depending on the mode) and makes the column handle as if it were connected to hydraulics.

I'm seriously annoyed by the retarded anti-Airbus sentiment on slashdot. We're geeks, we shouldn't care that much about the unjust financial support Airbus gets from Europe and instead just focus on fascinating technology.

From http://www.boeing.com/news/releases/2005/q1/nr_050214s.html

The two X-45As began the latest test, known as Peacekeeper, by departing from Edwards and climbing to altitudes of 24,500 and 25,500 ft respectively. Separated by approximately 25 miles and operating at Mach .65 (225 knots), the jets began their combat air patrol (CAP) mission to provide airborne alert over the exercise area. Tasked with suppression of enemy air defenses, the two vehicles were given two simulated pop-up ground threats to eliminate.

Once alerted to the first threat, the X-45As autonomously determined which vehicle held the optimum position, weapons and fuel load to properly attack the target. After making that decision, one of the X-45As changed course and the pilot-operator allowed it to attack the simulated ground-based radar. Following a successful strike, another simulated threat emerged and was subsequently destroyed by the second X-45A. The two X-45As completed their mission and safely returned to Edwards.

In the future, ground-based pilots will be controlling multiple combat aircraft with high-level commands: Patrol that sector, destroy target, refuel, RTB.

sure come a long way..

You always know a liar if he tells you, 'That'll never fly'.

Yes, because we know Boeing and Honeywell have no interest in keeping WiFi on a short, monetized leash in aircraft...

http://www.boeing.com/Features/2010/04/bds_feat_BBSN_031210.html

Wong Tsoo (can't find entry in Wikipedia oddly enough).

Nuff said.

There are good technical reasons why FDR data doesn't make sense to upload raw data automatically.

The pure FDR data is sampled at a high data rate, which varies according to model of FDR. The most modern systems also collect hundreds of data points at a time. This is discussed in the article, though I'd challenge some of their bandwidth calculations... the sample rates they quote seem very low (for modern systems), though I don't have my books in front of me.

What DOES make sense (and again, the article does address this), is having computing capability in the FDR (or outside of it, as it wouldn't need to be crash-worthy) that filters the data and ID's in real-time out-of-normal events and reports them.
In fact, most airlines already use a system like this, but not for the purpose of crash monitoring, but to detect aircraft problems in flight and alert ground crew so they can they can be prepared to fix them before the pilots even know there was a problem.

The issue is that this uplink capability can't replace the on-board FDR recording capability. That black box must still be there, as during the crash sequence, there is a good chance your satcom/etc systems will fail before the final crash. So this can augment, but not replace.

They also discuss adding a capability to comb through the complete raw data (you can just download it on landing as another route). Yep, great idea, but already being done by many airlines.
See http://www.boeing.com/commercial/aviationservices/brochures/Airplane_Health_Management.pdf

And in fact, the military is using the FDR data to check their pilot's proficiency as well as the aircraft performance:
See http://www.navair.navy.mil/PMA209/_Documents/MFOQA_101_20090224.ppt

"The US could bomb the shit out of the whole world if they really wanted to, and *everyone* knows that."

No. BTW, the B-1s don't carry nukes, nor do we have enough strategic bombers to level any major city with conventional weapons unless given months to do it, extreme force concentration, vast amounts of munitions, and few/no other missions. The days of darkening the skies with SAC are ancient history.

http://www.boeing.com/defense-space/military/b1-lancer/index.html

You are utterly ignorant, and unless you are some idiot teenager whose youthful frothing is stupid but somewhat understandable, please remove yourself from the gene pool by suicide.

    It's the same argument that an automobile manufacturer doesn't release the detailed specs of a vehicle, because the owners manual doesn't show a breakdown of the engine. They are available (for a price, of course) to the people that need the information.

    Here's the list of manuals for a Boeing 777.

    But for both aircraft and auto manufacturers, I don't believe they release detailed specs of say the software that makes their vehicles work. I doubt A&P mechanics are fixing software flaws in the autopilot, just as auto mechanics can't fix the software in the cruise control. It's the same as a doctor wouldn't be able to change the software controlling a pacemaker.

    I know plenty of automobile electronics have been reverse engineered, but that's due to the number available to work with, and the potential profit to be had from tuning the software. Most of us wouldn't know where to get our hands on a new or used pacemaker to begin reverse engineering it. I definitely wouldn't be able to get my hands on a new or used 777, nor have anywhere to store it. It's a bit bigger than most of our garages, and I can't imagine our significant others not minding that we have one in the garage.

The great majority of time spent on designing and testing a modern jet is done on a computer. For example, the 787 Dreamliner project used 800,000 hours of computation time on Cray supercomputers, 15,000 hours of wind tunnel testing and substantially less time for actual flight testing -- http://www.boeing.com/commercial/787family/programfacts.html

By the time a design is ready for wind tunnel testing all of its primary handling characteristics are almost fully established. Computers can model everything from aerodynamic characteristics of the airplane to static structural analysis of the airframe to even simulating resonance frequencies of the airplane body.

The MIT H-series looks rather like the Boeing X-48B: http://www.boeing.com/news/releases/2006/q4/061027b_nr.html Regarding the D-series - is it using ducted Propfans? - I couldn't find any information. The biggest problem with the Propfan technology appeared to be the noise produced by blades spinning at near or above supersonic speed. But it didn't seem insurmountable and ducting would seem like an obvious place to start in order to mitigate it. Although obvious to someone who has no aerospace training whatsoever, probably means "obviously stupid" in engineering terms.

No. Reusable has been shown to be a money pit and failed too much. It was expensive for the US, it was expensive for the Soviets.

Um, you can't make statements like that based on 2 data points utilizing technology from 30 years ago. The X-37B's requirements are quite a bit simpler (e.g. don't have to carry 50,000 pounds to orbit, don't need extreme crossrange capability, don't need to carry humans, etc.) than the Shuttle or Soviet Buran, and technology has progressed quite a bit since the 1970s. Heck, I'll just paste from Boeing's fact-sheet:

http://www.boeing.com/defense-space/ic/sis/x37b_otv/x37b_otv.html

The X-37B is one of the world's newest and most advanced re-entry spacecraft. Designed to operate in low-earth orbit, 110 to 500 miles above the Earth at a nominal speed of about 17,500 miles per hour, the vehicle is the first since the Space Shuttle with the ability to return experiments to Earth for further inspection and analysis.

Because the X-37B can be returned to Earth, reused, and is designed to be highly flexible and maneuverable, its contributions to space exploration will result in making space access more routine, affordable and responsive.

The X-37B features many elements that mark a first in space use. The X-37B is one-fourth the size of the Space Shuttle, and relies upon the same family of lifting body design. It also features a similar landing profile. The vehicle was built using lighter composite structures, rather than traditional aluminum. A new generation of high-temperature wing leading-edge tiles will also debut on the X-37B. These toughened uni-piece fibrous refractory oxidation-resistant ceramic (TUFROC) tiles replace the carbon carbon wing leading edge segments on the Space Shuttle. The X-37B will also use toughened uni-piece fibrous insulation (TUFI) impregnated silica tiles, which are significantly more durable than the first generation tiles used by the Space Shuttle. Advanced conformal reusable insulation (CRI) blankets are used for the first time on the X-37B.

All avionics on the X-37B are designed to automate all de-orbit and landing functions. Additionally, there are no hydraulics onboard the X-37B; flight controls and brakes use electromechanical actuation.

The on-orbit duration of the X-37B will vary based upon mission requirements, but has the ability to perform missions lasting up to 270 days.

The objectives of the first flight are to demonstrate that the X-37B is able to conduct long-duration operations, and to enable scientists to understand the long-term effects on system components, such as the structure and future payloads. The successful first flight will include achieving orbit, de-orbiting, and safely landing at the primary return location, Vandenberg Air Force Base, or Edwards Air Force Base, if necessary.

And is anyone still running any bare Aluminum? I certainly wouldn't, it leads to corrosion.

Yes, American Airlines has never painted their aircraft (in part to reduce weight). I don't think they've had any trouble with corrosion, and their MD-80s are going on 30 years old.

Boeing has a discussion of painting aircraft. They mention corrosion, and to a quick read, it looks like washing aircraft is more important than paint to reducing corrosion.

Some great photos in there.

You don't have to be an aero engineer to know that you don't want your engine looking like that.

Shutting down most of Europe's airspace was entirely the right decision. All it would take is one flight through an unexpected dust cloud to produce a near-disaster, if not a crash. That's happened at least five times in the past. Read Boeing's advisory on volcanic ash.

Read Branson's autobiography? Several times in his life, he's been involved in adventure vacations that left someone else dead. This is not someone you want making risk management decisions for others.

The big problem now is that the airlines are botching the logistics of getting people back where they're supposed to be. There are people being told they can't get a flight until mid-May, because they booked a flight using frequent-flyer miles or via some discount deal that has a low priority. They can't get the airline on the phone, and they get hit with heavy roaming charges while on hold. This is really tough on people in transit running out of money.

Don't know if you put any stock in what an aircraft manufacturer might say on the subject, but...

http://www.boeing.com/commercial/aeromagazine/aero_09/volcanic_story.html

Summary: If you find yourself flying into an ash cloud, turn around immediately.

So, yeah, maybe Branson wants a check, but flying into ash clouds is a very bad idea. And they don't show up on weather radar.

There are thick ash clouds and thin ones. No, you shouldn't have been flying planes in Iceland or northern UK, but halting flights as far south as Turkey certainly seems to have been unwarranted. There is particle-per-million level below which the Boeing bulletin fails to be applicable, and it appears most of Europe was below that level during most of the ban.

Don't know if you put any stock in what an aircraft manufacturer might say on the subject, but...

http://www.boeing.com/commercial/aeromagazine/aero_09/volcanic_story.html

Summary: If you find yourself flying into an ash cloud, turn around immediately.

So, yeah, maybe Branson wants a check, but flying into ash clouds is a very bad idea. And they don't show up on weather radar.

I'll be staying home, thanks.

Here's some information from Boeing on the volcanic ash and airliners.

sPh

Delta IV vehicles can launch payloads weighing from 4,300 kg (9,480 lb) to 12,980 kg (28,620 lb) to GTO, and can lift over 23,000 kg (50,000 lbs.) to LEO. link

The LEO numbers aren't as firm as the numbers I've seen elsewhere but the GTO numbers are much closer to my numbers than yours. I'd assume that the heavy payload duty for US launches will shift to the Delta-IV now that we no longer have the Shuttle to perform heavy lifts.

Falcon-9 Heavy is another interesting lifter in that the $/lb to LEO is about 1/3rd the cost of other launchers, will be very interesting to see if it is ever built, and if they can hit their pricing target.

Also:

• Price of a 737: $50,000,000 or more.
• Price of a Toyota Prius: $20,000 or more.

Even if the computers in the 737 cost 1,000 times as much per unit as those in the Prius, it's still cheaper per unit sold to fit 3 to the aircraft than it is to fit 3 to the car. Plus, of course, avionics failure is pretty much guaranteed to end in bad press for Boeing; many failure modes for the Prius's computers end up with the driver being blamed, and no bad press for Toyota (car accidents are so much more common than plane accidents that they're not automatically newsworthy).

"The" cause is that humans make mistakes.

The "flawed human" defense works great for lawyers and TV dramas, but I am always surprised and disappointed when I hear it from engineering types. The problem with that argument is that you can't do anything to fix it!

I suggest you read up on Human Factors Engineering. Take a systems approach and you will find that humans are a component like any other, with measurable tolerances and response ranges. One of the best human factors success stories is aviation safety. Most FAA incident reports still include "pilot error," but also instrument design, automation design, training, schedule-induced fatigue, and other things you can actually change to reduce the likelihood of that incident happening again.

It would seem to me if every citizen knew how to properly shoot a rifle, odds are pretty good one of those things could be knocked out of the sky with a barrett. It would cost all of us a heck of a lot less money too. In fact... this is exactly the sort of thing the 2nd amendment was written for. "The people" defending themselves from attack.

Look, I'm a strong proponent of the 2nd Amendment, and a licensed concealed-carry instructor to boot. And having a bunch of citizens attempt to shoot down a drone is simply a BAD IDEA. What goes up must come down, no? Every year on the 4th of July, some idiot kills a completely innocent bystander because he decided to shoot up in the air, not realizing that the bullets have to land somewhere. Instead, we'd be better off looking at taking airborne missile-defense laser weapons and adapting them to ground-based installations. Of course, these drones are small, fast, and stealthy, so we would probably have to include a system to find the drones in real-time and link that system to the ground-based air defense. We'd still have to worry about legitimate air-traffic, and depending upon the strength of the lasers, possibly objects in low-earth-orbit. But while it would probably be way too expensive a solution to put into place, it would be way more safe than a bunch of us gun-owners trying to shoot down a drone!

spent 5 hours on a flight next to a woman whose blanket clearly was Catted

Would a light face mask help if you can plug it into the air vent? The mask doesn't have to be hermetic, it only needs to maintain positive pressure over your nose and mouth. You'd still be breathing some cat in if you need to leave your seat, but that's just seconds... perhaps survivable.

I have no allergies, but I might want to use such a mask myself all the time, just to protect against viruses and such. The 50% of the air is coming from outside, so it is clean, and the other 50% is filtered. It definitely makes sense if the area has local contaminants.

Yeah, but I don't see that wire being much bigger than 30 gauge (which is about 1cm thick; pretty darn thick). 190,000 meters (it was meters, not feet) of 30 gauge copper wire only weighs a little over 200 pounds. That's less than a passenger + luggage.

Um, AWG 30 is less than a millimeter, not a centimeter, and a lot of the wiring in an airplane would be bigger than 30 gauge.

On the OP's link they claim that 2% of the weight of a 747 is copper. Boeing says a fully loaded 747 is about 875,000 lbs . If this post is accurate, carbon nanotube conductors might weight as little as 1/7 of what copper conductors weigh. My calculator says that means a savings of 15,000 pounds.

That's a pretty porky passenger, but I might have sat next to him on an Oregon-Ohio trip.

Yup, I can confirm. i interviewed for a programming position at Boing on this project (DES) effort in 1997. There's also been lots of online material describing this chemical laser project over the years...

Here's a link on Boeing's own site from 1999 about it: http://www.boeing.com/news/releases/1999/news_release_990421b.html

How can commercial entities, who have so far demonstrated only toy rockets, possibly be closer to achieving space flight than NASA

Huh? Maybe you should look up who builds the Atlas and Delta boosters. Commercial entities have been flying rockets, *big* rockets, for decades.

This way If you like airships

Or this It uses regular length runways (build a temp out of gravel at the site a la WWII

And anyway, L2 is unstable and requires constant station keeping.

Minimal.

they don't ever drift apart from each other

Flying in formation is a solved problem.

The moon is a big hunk of rock.

Comprising a gravity well covered in nasty electrostatic dust and exerting a force on any structures, requiring them to have dramatically greater structural integrity.

Plus, the lunar far side is also blocked from the Sun for two solid weeks at a time, which also eliminates another big source of radio noise.

This can also be a bad thing for a lunar telescope, as it's going to dramatically change it's temperature over the course of a lunar month, altering its shape. Which is a huge problem. Also, the moon has a (tenous) ionosphere, and even "aurora"-like phenomena from electrostatically levitated dust.

Here's some dudes at Caltech laying out the arguments

And here's serious criticism of it.

Airbus A330-200 dimensions:
Overall length: 58.8 m
Fuselage diameter: 5.64 m
Wing area: 361.6 sq. m
Total silhouette area (target area for meteorite): 58.8 x 5.64 + 361.6 = 693.232 sq. m

FlightAware says there are about 5000 airborne commercial aircraft flying into or out of U.S. airports right now. For arguments sake, let's assume 5 times that amount for total currently-airborne global commercial flights (25,000 planes in the air).

Let's also assume (for arguments sake) that all those airplanes have the "target" area of an Airbus A330-200 (total target area of all airborne planes then equals 18,080,000 sq. meters, or 18 sq. km).

Let's also assume (however absurd) there has been this many planes, of this size, in the air since 1959.

Taking the high-end estimate (approx. 84,000/yr, or 4.2M since 1959) for the number of meteorites greater than 10 grams that strike the Earth's surface each year (assuming, of course, that all of these would bring down an aircraft with any contact) and given the surface area of the Earth at 510,072,000 km, the chance that a meteorite would hit any (as in, just a single) plane within the last 50 years would be about 13.8% (or .138) whereas there have been over 1900 non-meteorite-caused major commercial accidents since 1959.

The upshot of all this, even working with absurd (in the meteorites' favor) numbers, the odds of the Air France Flight 447 accident being caused by a meteorite are astronomical .

Some parts of the 747 may have been produced in Hawthorne, but the 747 is (and always has been) assembled in a Everett, WA. The article mentions the Hawthorne facility having a "massive hangar". The real thing is gigantic (eg: 90' ceiling).
http://www.boeing.com/commercial/facilities/

As far as using "biofuels" on jet engines - it's been done. Remember, JetA is pretty much kerosene which is pretty much diesel.

As far as scuba diving from a oil rig - you're pretty much correct. Lots of critters like to hang around the pylons so it wouldn't be as boring as just dropping off in the middle of the Gulf, but I can think of lots better places to dive.

We have noise pollution laws for everything but aircraft.

You have no idea what you are talking about. Ten seconds on Google would get you to Title 14, Part 36 of the Code of Federal Regulations, "Noise Standards: Aircraft Type and Certification". All airplanes built in the United States are certified to this standard. Europe (EASA) has very similar regulations, and most of the other national regulatory bodies in the world pattern their regulations off of the FAA/EASA regulations.

That same FAA disregard for anything that might negatively impact total air passenger miles got us 9/11

Wait, what? Are you seriously implying that 9/11 was the FAA's fault? Citation please.

and continues to cause well documented health and mortality effects in areas around major airports.

Please point me in the direction of some of these "well documented ... effects."

Enlightened governments are re-locating their airports away from population centers and building fast and convenient light rail to make it convenient to get to them.

Light rail is awesome, and has nothing to do with the FAA.

Another thing government could be doing to balance the substantial subsidies air industries have enjoyed is divert some of those dollars to rail and R&D into quieter and more efficient aircraft.

Ok, but your ticket prices will go up.

Also, you asked for quieter and more efficient aircraft, so here you go.

Airlines are still focused overwhelmingly on the next quarter and the FAA doesn't care.

The FAA's job is not to make the airlines profitable. It's to make them safe.

Fly by wire planes? I hate to break it to you, but outside of the occasional ultralight (which would have trouble damaging a car, let alone causing mass destruction), fly by wire doesn't exist.

"One of the A300-600 and A310's notable innovations had been the introduction of electrical signalling on secondary flight controls, replacing the web of cables and pulleys tradionally used. Béteille wanted to take this evolution further with the next Airbus aircraft - to computer-driven digital "fly-by-wire", in which the deflections of the flying control surfaces on the wing and tail are no longer driven directly by the pilots' controls, but by a computer which calculates exactly which control surface deflections are needed to make the aircraft respond as the pilot wishes ... The A320's fly-by-wire technology was not only a way of improving flight controls and reducing weight..."

"The flight-control system for the 777 airplane is different from those on other Boeing airplane designs. Rather than have the airplane rely on cables to move the ailerons, elevator, and rudder, Boeing designed the 777 with fly-by-wire technology. As a result, the 777 uses wires to carry electrical signals from the pilot control wheel, column, and pedals to a primary flight computer."

On a per-passenger basis an airliner is about as fuel-efficient as an SUV

Not at all. Fuel economy for a Boeing or Airbus plane built after 1990 and filled to 75% capacity should be about 60 mpg per person. I wasn't in the mood to do the math, but this article from Boeing implies a 747 built in 2002 and filled to 75% capacity gets better than 80 mpg per person. http://www.boeing.com/commercial/news/feature/mileage.html

A friend of mine explained the situation to me. This is third-hand information; look it up for confirmation before you fully trust it.

Originally, Boeing got the contract for the tankers, back in 2001 or so. But in 2005, the contract was taken away from Boeing and put up for bid again, because Congress investigated and found some illegal influencing done by some lobbyists. At least two people went to prison over this.

So now, the Air Force still needed tankers, but they needed to put the contract up for bid. But according to my friend, only Boeing was really ready to bid on the contract. So, because the USAF didn't want to make it look at all like Boeing was getting it without any competition, they bent over backwards to help Airbus participate in the process. They bent over way too much, and helped Airbus way too much; my friend really feels that the result was unfair and the Boeing tanker deserved to win.

So Airbus won the contract, and Boeing protested strenuously. (I live in Washington state, and a lot of Washington state voters, as well as Representatives and Senators, also lobbied furiously for this decision to be reconsidered.) So now the tanker is being put up for bid AGAIN.

My friend feels that with a fair competition, Boeing will win the contract easily. I kind of hope so, since Boeing is the "home team" for my state.

Meanwhile, the aging old tanker airplanes the USAF has now continue to fly, and continue to cost more to operate than new airplanes would.

Here's a Boeing press release. It's obviously partisan in favor of Boeing but it lines up with what my friend told me.

http://www.boeing.com/news/releases/2008/q1/080311b_nr.html

Here's a Washington Post story about this. It agrees factually with the above, but does not go into the history of why the Air Force handled the contract the way it did.

http://www.washingtonpost.com/wp-dyn/content/story/2008/06/19/ST2008061900091.html

Actually you do.

Yeah, because of the fifty busiest ports in the world, Canada has one on the list (Vancouver) and the United States has six and five of them move more cargo than Vancouver.

The only ports that freeze are in the great lakes, you know the ones that ship out the majority of the grain to the rest of the world.

This confuses me. Not the freezing ports part, but the grain shipping, because the US exports twelve times as much grain as Canada. With 22% going via California, and the next 16% going via Washington and New York.

It means that if you throw a hissy fit, we simply say 'our market is now europe' and they buy our goods, or japan, or anyone else.

Yeah, because Asia is going to totally want to import goods from a half way around the world where it's twice as expensive to produce the goods, than they will from multiple countries right next door where labor is cheaper. I mean why import goods from Malaysia into Japan when you can ship stuff from Canada.

And yeah, I agree, it's going to be totally trivial for Canada to find new markets for 80% of their total exports. Not.

While you're very good at consuming our goods, and tell me something do you even have the manufacturing base left to make anything?

I don't know. Maybe air planes, heavy equipment, trucks, microprocessors, DRAM & flash. Then of course we have things like tanks, airplanes & submarines, aircraft carriers, fighter planes & submarines. And there are vaccines and medicines.

But, hey, we import our socks, so yeah, I can totally see why you'd think the US isn't capable of producing anything.

The only reason the US imports manufactured goods is because it's cheaper. Barring protectionist policies, every industrialized country does the same.

Air borne Laser and Here.

What I find interesting is that the nose can shoot not just forward, but also 90 including UP. It has the ability to take out not just a missile, but the sats that communicate to them. Personally, I think that the later capability is more important than the missiles. I am not certain what Obama is going to do, but I doubt that he will turn this capability off. I view it as being far more important than the ABM system.

Im not sure why it is tagged vaporware since a similar blended wing body design that Boeing and NASA are working on flew in 2007. http://www.boeing.com/phantom/news/2007/q3/070726c_nr.html

What makes the Chandrayaan mission interesting is the cost - USD 87 million which is about the same as the price of a Boeing 737-900ER.

http://www.boeing.com/commercial/prices/index.html

If USD 87 million is all it takes to send a mission to the moon, it signifies much lower costs for putting up satellites around the earth.

A deranged person can be "dangerous" with anything. Look at all of the "creative" prisoners that create dangerous thing from non-banned materials like tissues, plastic spoons, etc. However determining the mental state of an individual is difficult so we have resorted to the "standard" ban the device or material in order to stop possible "events".
Back to the original issue about interference from electronic devices. Boeing did an study of this and they published this in their magazine Aero and here is a text link:
http://www.boeing.com/commercial/aeromagazine/aero_10/interfere_textonly.html
Granted this article is 8 years old but they had similar issues back then and they did verify any real correlation between electronic devices and interference with flight or navigation control. However we need to do more study in this field with current devices to check this again.

Wrong. Wrong. Wrong.

Stats on the Boeing jets from Boeing.com

"
Advanced 707-320B

Wingspan 145 feet 9 inches (44.42 m)
Length 152 feet 11 inches (46.6 m)
Wing Area 3,010 square feet (280 m2)
Gross Weight 336,000 pounds (152,400 kg)
Cruising Speed 607 mph (977 km/h)
Range 6,160 miles (9,913 km)
Service Ceiling 36,000 feet (10,973 m)
Power Four Pratt & Whitney JT3D turbofans of 18,000 pounds thrust each
Passenger Cabin 141 passengers mixed class or a maximum of 189 all economy"

http://www.boeing.com/commercial/707family/product.html [boeing.com]

"Technical Characteristics -- Boeing 767-200ER

Passenger Seating Configuration
                        Typical 3-class 181
                        Typical 2-class 224
                        Typical 1-class up to 255
Cargo 2,925 cu ft (82.9 cu m)
Engines 2
maximum thrust
Pratt & Whitney PW4000 60,200 lb

GE CF6-80C262,100 lb

Maximum Fuel Capacity 23,980 U.S. gal (90,770 L)
Maximum Takeoff Weight 395,000 lb (179,170 kg)
Maximum Range 6,590 nautical miles (12,200 km)

Typical city pairs:
New York to Beijing
Typical Cruise Speed at 35,000 feet Mach 0.80 (530 mph, 851 kph)
Basic Dimensions
                        Wing Span 156 ft 1 in (47.6 m)
                        Overall Length 159 ft 2 in (48.5 m)
                        Tail Height 52 ft (15.8 m)
                        Interior Cabin Width 15 ft 6 in (4.7 m)"

http://www.boeing.com/commercial/767family/pf/pf_200prod.html [boeing.com]

707 is 85-90% of 767 spec in all key areas.

Wrong. Wrong. Wrong.

Stats on the Boeing jets from Boeing.com

"
Advanced 707-320B

Wingspan 145 feet 9 inches (44.42 m)
Length 152 feet 11 inches (46.6 m)
Wing Area 3,010 square feet (280 m2)
Gross Weight 336,000 pounds (152,400 kg)
Cruising Speed 607 mph (977 km/h)
Range 6,160 miles (9,913 km)
Service Ceiling 36,000 feet (10,973 m)
Power Four Pratt & Whitney JT3D turbofans of 18,000 pounds thrust each
Passenger Cabin 141 passengers mixed class or a maximum of 189 all economy"

http://www.boeing.com/commercial/707family/product.html [boeing.com]

"Technical Characteristics -- Boeing 767-200ER

Passenger Seating Configuration
                        Typical 3-class 181
                        Typical 2-class 224
                        Typical 1-class up to 255
Cargo 2,925 cu ft (82.9 cu m)
Engines 2
maximum thrust
Pratt & Whitney PW4000 60,200 lb

GE CF6-80C262,100 lb

Maximum Fuel Capacity 23,980 U.S. gal (90,770 L)
Maximum Takeoff Weight 395,000 lb (179,170 kg)
Maximum Range 6,590 nautical miles (12,200 km)

Typical city pairs:
New York to Beijing
Typical Cruise Speed at 35,000 feet Mach 0.80 (530 mph, 851 kph)
Basic Dimensions
                        Wing Span 156 ft 1 in (47.6 m)
                        Overall Length 159 ft 2 in (48.5 m)
                        Tail Height 52 ft (15.8 m)
                        Interior Cabin Width 15 ft 6 in (4.7 m)"

http://www.boeing.com/commercial/767family/pf/pf_200prod.html [boeing.com]

707 is 85-90% of 767 spec in all key areas.

Wrong. Wrong. Wrong.

Stats on the Boeing jets from Boeing.com

"
Advanced 707-320B

Wingspan 145 feet 9 inches (44.42 m)
Length 152 feet 11 inches (46.6 m)
Wing Area 3,010 square feet (280 m2)
Gross Weight 336,000 pounds (152,400 kg)
Cruising Speed 607 mph (977 km/h)
Range 6,160 miles (9,913 km)
Service Ceiling 36,000 feet (10,973 m)
Power Four Pratt & Whitney JT3D turbofans of 18,000 pounds thrust each
Passenger Cabin 141 passengers mixed class or a maximum of 189 all economy"

http://www.boeing.com/commercial/707family/product.html

"Technical Characteristics -- Boeing 767-200ER

Passenger Seating Configuration
            Typical 3-class 181
            Typical 2-class 224
            Typical 1-class up to 255
Cargo 2,925 cu ft (82.9 cu m)
Engines 2
maximum thrust
Pratt & Whitney PW4000 60,200 lb

GE CF6-80C262,100 lb

Maximum Fuel Capacity 23,980 U.S. gal (90,770 L)
Maximum Takeoff Weight 395,000 lb (179,170 kg)
Maximum Range 6,590 nautical miles (12,200 km)

Typical city pairs:
New York to Beijing
Typical Cruise Speed at 35,000 feet Mach 0.80 (530 mph, 851 kph)
Basic Dimensions
            Wing Span 156 ft 1 in (47.6 m)
            Overall Length 159 ft 2 in (48.5 m)
            Tail Height 52 ft (15.8 m)
            Interior Cabin Width 15 ft 6 in (4.7 m)"

http://www.boeing.com/commercial/767family/pf/pf_200prod.html

Now as this picture shows...
http://thewebfairy.com/killtown/images/wtc-gallery/nist1-3d/6-19_wtc2-collapsing.jpg

No "building being dropped on another building" pulverization nonsense happened.

As the picture clearly shows, the atomized debris dust preceded the collapse. The dust and debris is being blown out of the site of the initial area of collapse at a high rate of speed such as one would expect to see when explosives have been used.

Wrong. Wrong. Wrong.

Stats on the Boeing jets from Boeing.com

"
Advanced 707-320B

Wingspan 145 feet 9 inches (44.42 m)
Length 152 feet 11 inches (46.6 m)
Wing Area 3,010 square feet (280 m2)
Gross Weight 336,000 pounds (152,400 kg)
Cruising Speed 607 mph (977 km/h)
Range 6,160 miles (9,913 km)
Service Ceiling 36,000 feet (10,973 m)
Power Four Pratt & Whitney JT3D turbofans of 18,000 pounds thrust each
Passenger Cabin 141 passengers mixed class or a maximum of 189 all economy"

http://www.boeing.com/commercial/707family/product.html

"Technical Characteristics -- Boeing 767-200ER

Passenger Seating Configuration
            Typical 3-class 181
            Typical 2-class 224
            Typical 1-class up to 255
Cargo 2,925 cu ft (82.9 cu m)
Engines 2
maximum thrust
Pratt & Whitney PW4000 60,200 lb

GE CF6-80C262,100 lb

Maximum Fuel Capacity 23,980 U.S. gal (90,770 L)
Maximum Takeoff Weight 395,000 lb (179,170 kg)
Maximum Range 6,590 nautical miles (12,200 km)

Typical city pairs:
New York to Beijing
Typical Cruise Speed at 35,000 feet Mach 0.80 (530 mph, 851 kph)
Basic Dimensions
            Wing Span 156 ft 1 in (47.6 m)
            Overall Length 159 ft 2 in (48.5 m)
            Tail Height 52 ft (15.8 m)
            Interior Cabin Width 15 ft 6 in (4.7 m)"

http://www.boeing.com/commercial/767family/pf/pf_200prod.html

Now as this picture shows...
http://thewebfairy.com/killtown/images/wtc-gallery/nist1-3d/6-19_wtc2-collapsing.jpg

No "building being dropped on another building" pulverization nonsense happened.

As the picture clearly shows, the atomized debris dust preceded the collapse. The dust and debris is being blown out of the site of the initial area of collapse at a high rate of speed such as one would expect to see when explosives have been used.

Wrong. Wrong. Wrong.

Stats on the Boeing 707-320B from Boeing.com

"Advanced 707-320B Wingspan 145 feet 9 inches (44.42 m)
Length 152 feet 11 inches (46.6 m)
Wing Area 3,010 square feet (280 m2)
Gross Weight 336,000 pounds (152,400 kg)
Cruising Speed 607 mph (977 km/h)
Range 6,160 miles (9,913 km)
Service Ceiling 36,000 feet (10,973 m)
Power Four Pratt & Whitney JT3D turbofans of 18,000 pounds thrust each
Passenger Cabin 141 passengers mixed class or a maximum of 189 all economy"

http://www.boeing.com/commercial/707family/product.html [boeing.com]

Technical Characteristics -- Boeing 767-200ER
Passenger Seating Configuration
            Typical 3-class 181
            Typical 2-class 224
            Typical 1-class up to 255
Cargo 2,925 cu ft (82.9 cu m)
Engines 2
maximum thrust
Pratt & Whitney PW4000 60,200 lb

GE CF6-80C262,100 lb

Maximum Fuel Capacity 23,980 U.S. gal (90,770 L)
Maximum Takeoff Weight 395,000 lb (179,170 kg)
Maximum Range 6,590 nautical miles (12,200 km)

Typical city pairs:
New York to Beijing
Typical Cruise Speed at 35,000 feet Mach 0.80 (530 mph, 851 kph)
Basic Dimensions
            Wing Span 156 ft 1 in (47.6 m)
            Overall Length 159 ft 2 in (48.5 m)
            Tail Height 52 ft (15.8 m)
            Interior Cabin Width 15 ft 6 in (4.7 m)"

http://www.boeing.com/commercial/767family/pf/pf_200prod.html [boeing.com]

707 and 767 is within 85-90% of each other in every key area of measurement.

If I remember right, Boeing intended the 767 to be almost a direct replacement for the 707.

Now as this picture shows...
http://thewebfairy.com/killtown/images/wtc-gallery/nist1-3d/6-19_wtc2-collapsing.jpg [thewebfairy.com]

No "building being dropped on another building" nonsense happened.

As the picture clearly shows, the atomized debris dust preceded the collapse. The dust and debris is being blown out of the site of the initial area of collapse at a high rate of speed such as one would expect to see when explosives have been used.

Wrong. Wrong. Wrong.

Stats on the Boeing 707-320B from Boeing.com

"Advanced 707-320B Wingspan 145 feet 9 inches (44.42 m)
Length 152 feet 11 inches (46.6 m)
Wing Area 3,010 square feet (280 m2)
Gross Weight 336,000 pounds (152,400 kg)
Cruising Speed 607 mph (977 km/h)
Range 6,160 miles (9,913 km)
Service Ceiling 36,000 feet (10,973 m)
Power Four Pratt & Whitney JT3D turbofans of 18,000 pounds thrust each
Passenger Cabin 141 passengers mixed class or a maximum of 189 all economy"

http://www.boeing.com/commercial/707family/product.html [boeing.com]

Technical Characteristics -- Boeing 767-200ER
Passenger Seating Configuration
            Typical 3-class 181
            Typical 2-class 224
            Typical 1-class up to 255
Cargo 2,925 cu ft (82.9 cu m)
Engines 2
maximum thrust
Pratt & Whitney PW4000 60,200 lb

GE CF6-80C262,100 lb

Maximum Fuel Capacity 23,980 U.S. gal (90,770 L)
Maximum Takeoff Weight 395,000 lb (179,170 kg)
Maximum Range 6,590 nautical miles (12,200 km)

Typical city pairs:
New York to Beijing
Typical Cruise Speed at 35,000 feet Mach 0.80 (530 mph, 851 kph)
Basic Dimensions
            Wing Span 156 ft 1 in (47.6 m)
            Overall Length 159 ft 2 in (48.5 m)
            Tail Height 52 ft (15.8 m)
            Interior Cabin Width 15 ft 6 in (4.7 m)"

http://www.boeing.com/commercial/767family/pf/pf_200prod.html [boeing.com]

707 and 767 is within 85-90% of each other in every key area of measurement.

If I remember right, Boeing intended the 767 to be almost a direct replacement for the 707.

Now as this picture shows...
http://thewebfairy.com/killtown/images/wtc-gallery/nist1-3d/6-19_wtc2-collapsing.jpg [thewebfairy.com]

No "building being dropped on another building" nonsense happened.

As the picture clearly shows, the atomized debris dust preceded the collapse. The dust and debris is being blown out of the site of the initial area of collapse at a high rate of speed such as one would expect to see when explosives have been used.

Wrong. Wrong. Wrong.

Stats on the Boeing 707-320B from Boeing.com

"Advanced 707-320B Wingspan 145 feet 9 inches (44.42 m)
Length 152 feet 11 inches (46.6 m)
Wing Area 3,010 square feet (280 m2)
Gross Weight 336,000 pounds (152,400 kg)
Cruising Speed 607 mph (977 km/h)
Range 6,160 miles (9,913 km)
Service Ceiling 36,000 feet (10,973 m)
Power Four Pratt & Whitney JT3D turbofans of 18,000 pounds thrust each
Passenger Cabin 141 passengers mixed class or a maximum of 189 all economy"

http://www.boeing.com/commercial/707family/product.html

Technical Characteristics -- Boeing 767-200ER
Passenger Seating Configuration
      Typical 3-class 181
      Typical 2-class 224
      Typical 1-class up to 255
Cargo 2,925 cu ft (82.9 cu m)
Engines 2
maximum thrust
Pratt & Whitney PW4000 60,200 lb

GE CF6-80C262,100 lb

Maximum Fuel Capacity 23,980 U.S. gal (90,770 L)
Maximum Takeoff Weight 395,000 lb (179,170 kg)
Maximum Range 6,590 nautical miles (12,200 km)

Typical city pairs:
New York to Beijing
Typical Cruise Speed at 35,000 feet Mach 0.80 (530 mph, 851 kph)
Basic Dimensions
      Wing Span 156 ft 1 in (47.6 m)
      Overall Length 159 ft 2 in (48.5 m)
      Tail Height 52 ft (15.8 m)
      Interior Cabin Width 15 ft 6 in (4.7 m)"

http://www.boeing.com/commercial/767family/pf/pf_200prod.html

Now as this picture shows...
http://thewebfairy.com/killtown/images/wtc-gallery/nist1-3d/6-19_wtc2-collapsing.jpg

No "building being dropped on another building" nonsense happened.

As the picture clearly shows, the atomized debris dust preceded the collapse. The dust and debris is being blown out of the site of the initial area of collapse at a high rate of speed such as one would expect to see when explosives have been used.