X-48B First Test Flight

Boeing's futuristic plane passes its first flight test
Full Story
By Dominic Gates
Seattle Times aerospace reporter

Boeing completed the first test flight Friday of its latest blended-wing-body research aircraft, designated the X-48B.

The unmanned test vehicle represents a possible future aircraft that replaces the traditional tube-and-wing design with a shape resembling a manta ray -- essentially a flying wing.

The prototype, which has a 21-foot wingspan and weighs 500 pounds, flew for a half-hour at NASA's Dryden Flight Research Center at Edwards Air Force Base, Calif, climbing to an altitude of 7,500 feet.

Thanks to greater aerodynamic efficiency, a blended-wing-body design could be built much bigger than current planes and carry more passengers or cargo.

For commercial applications, a big drawback is that most passengers in the cavernous interior would be far from windows. But Boeing is first looking at such applications as military cargo.

George Muellner, president of the Advanced Systems unit in Boeing's defense division, said at the Paris Air Show last month that, with continued government funding, a blended-wing-body military-cargo plane could be in use sometime between 2015 and 2020.




[edit on 25-7-2007 by MrKnight]

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[edit on 13/11/2007 by Mirthful Me]

For the tanker and cargo role this design would be ideal as it offers greater payload as well as more efficiency. Although I cannot see a BWB tanker or cargo aircraft reaching IOC in the next decade.

Originally posted by WestPoint23
For the tanker and cargo role this design would be ideal as it offers greater payload as well as more efficiency. Although I cannot see a BWB tanker or cargo aircraft reaching IOC in the next decade.

A BWB has less moving parts, and is a simple design. The time to engineer, manufacture and develop a BWB will be less than that of a tube and wing design.

Since Boeing is already using the X-48B to use as a test flight aircraft, and they have already have done extensive research useing wind tunnels, it is only a matter of funding to develop a size slightly larger that can be used for commercial freighter and military purposes.

There have already been reports that Boeing is getting customers for a BWB, and if there is additional interest from the military, it will not be long until a version is in production.

BWB Customers

I doubt that the BWB that will first go into service will be the 1,000 passenager version, as it will take alot of time to develop a model that size.

A modest 100 to 150 foot wingspan BWB that can fill the role of a small military freighter could be likely by 2015 - 2020.

Another Article:
Flight Global



[edit on 26-7-2007 by MrKnight]

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[edit on 13/11/2007 by Mirthful Me]

Good to hear that this long-touted project is going forward, but I'm afraid that I've got to cast some of my own concerns out into the open.

IMHO, I don't think that this design will work properly with the airport infrastructure currently in place. And I really do hate to cast a shadow on such a fantastic, unique idea. The sheer wingspan on one of those aircraft has got to be enormous. So how will it fit at an airport? Not just at the gate, but on a runway. Will the runways have to be widened to fit this mammoth aircraft? If they do, it could be an unfortunate speed bump in the path of the BWB.

Also, how well can the wings flex? I know that we have plenty of modern materials and composites capable of handling stress, but going along with the idea of a huge wingspan, how will this beast react to turbulence? In such an aircraft you'd have to have large support beams or a complex inner skeleton, but this takes away from space necessary for other things. Passenger space will undoubtedly be the big one with airlines.

But, I suppose we should wait til this thing has had larger scale tests to be sure about how it will turn out.

Originally posted by MrKnight
A BWB has less moving parts, and is a simple design. The time to engineer, manufacture and develop a BWB will be less than that of a tube and wing design.

Absolute complete utter rubbish.


What part of a BWB is easier to manufacture than a conventional tube and wings?

New procedural measures will have to be made... many of them for issues we are probably not even aware of yet!

New testing procedures to verify if the thing is safe, if the thing will be safe for an extended time.

Originally posted by MrKnight
Since Boeing is already using the X-48B to use as a test flight aircraft, and they have already have done extensive research useing wind tunnels, it is only a matter of funding to develop a size slightly larger that can be used for commercial freighter and military purposes.

Yeah, only a few billion dollars...

It would be a bigger undertaking than the A380 and B787 put together.

Originally posted by MrKnight
There have already been reports that Boeing is getting customers for a BWB, and if there is additional interest from the military, it will not be long until a version is in production.

Boeing is working with two potential customers to define a commercial freighter variant of its blended wing body large transport aircraft

Do you actually understand what that means?

It means Boeing are asking them what size they would like it to be (in terms of volume:payload), how big and where the doors go etc etc

Originally posted by MrKnight
I doubt that the BWB that will first go into service will be the 1,000 passenager version, as it will take alot of time to develop a model that size.

A modest 100 to 150 foot wingspan BWB that can fill the role of a small military freighter could be likely by 2015 - 2020.

Possible... possible by 2020.


Any passenger versions of BWB will be 2030 or so (if even).

The idea isn’t groundbreaking. They’ve been test flown since the late 30s. Wonder why they didn’t pursue this flying wing concept to its logical conclusion? Probably because the decreased range and the small bomb bays which could not carry the atomic bomb then. This may have been the greatest deciding factor.


A picture of the N-9M


The first XB-35


The YB-49

www.yourzagi.com...


Pics Courtesy: Matt Taylor
Zagi™ and Fixx™ of Trick R/C
RC Groups

Originally posted by Darkpr0
Good to hear that this long-touted project is going forward, but I'm afraid that I've got to cast some of my own concerns out into the open.

IMHO, I don't think that this design will work properly with the airport infrastructure currently in place. And I really do hate to cast a shadow on such a fantastic, unique idea. The sheer wingspan on one of those aircraft has got to be enormous. So how will it fit at an airport? Not just at the gate, but on a runway. Will the runways have to be widened to fit this mammoth aircraft? If they do, it could be an unfortunate speed bump in the path of the BWB.

Also, how well can the wings flex? I know that we have plenty of modern materials and composites capable of handling stress, but going along with the idea of a huge wingspan, how will this beast react to turbulence? In such an aircraft you'd have to have large support beams or a complex inner skeleton, but this takes away from space necessary for other things. Passenger space will undoubtedly be the big one with airlines.

But, I suppose we should wait til this thing has had larger scale tests to be sure about how it will turn out.

The wing span of the largest 800 passenger sized version would similar in width as a A380 or 747-400. The doors would be closer to the nose which will still be able to be used with the current systems.
How Stuff Works

Large BWB vs. 747-400



Keep in mind that this is with the larger version. As you can see it is only about half as long, so it will take up less hanger and ramp sapce.

As for your other concers, it has already been determined that the interior volume of a blended wing will be grater than traditional tubes. Just as a box offers more volume than a tube. NASA has stated this same concept here: NASA Page "Advantages of the blended wing-body concept include high fuel efficiency, low noise and a large payload volume for the size of the aircraft."

The additional lift and amount of control surfaces that can be placed on a blended wing will allow for better control when faced with turbelance. Also, the wide sing space and blended body reduces the wing loading, as well as the shape allows for better distribution over the airframe. A BWB had center body lift which reduces wing loading, and the desing of the wing allows for better weight and stress distribtion over the entire airframe.

More on Wing Loading: Wing Loading

"A blended wing-fuselage design often helps to reduce wing loading; in such a design (such as that found on the F-16 Fighting Falcon or MiG-29 Fulcrum), the shape of the fuselage generates some aerodynamic lift itself, improving wing loading while maintaining high performance."

Do you have any other concerns that I can address?

[edit on 30-7-2007 by MrKnight]

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[edit on 13/11/2007 by Mirthful Me]

Originally posted by kilcoo316
What part of a BWB is easier to manufacture than a conventional tube and wings?

All you are looking at is the outside design, but you are not taking intoconsideration all the the internal structure, and all of the control surfaces and parts that go into a tail of an aircraft.

The body of a BWB will not be any differnet to make than having differnt types of molds for the upper and lower surfaces, alomse of flat surfecs with slight bends in them. Then they will be put together over a very simple frame.

Dr. Liebeck has also stated the preliminary desings show that around 30% fewer parts will be required. I have heard him state similar thing in recent siminars.

LA Time Article from 2001

"The plane also would require about 30 percent fewer parts to make and emit less noise and pollution, Liebeck said. Another advantage is that the design can be easily scaled so that a plane could be made seating as few as 200 passengers or as many as 800."

Bob Lieback Siminar

Yeah, only a few billion dollars...

It would be a bigger undertaking than the A380 and B787 put together.

Every new aircraft takes billions to develop. But I doubt that a small blended wing will cost as much as the B787 and A380 together.

I have seen reports that both the A380 and 787 have each cost between 10 to 15 Billionto develop. A 200 Passenager sized commercial cargo / millitary freighter would not take 30 Billion to develop. I would put the cost for a C-130 sized military / commercial freighter at 3 to 5 billion. A very attractive risk for that particular market given future trends for military replamcement market ofr that size, and the fuel saving of a BWB for a commerical freighter.

It means Boeing are asking them what size they would like it to be (in terms of volume:payload), how big and where the doors go etc etc

Please give a round of applause for "Captain Obvious"! Of course that is what is going on. This would not be going on if Boeing was not serious, and if the potential customers were not taking it into consideration.

Any passenger versions of BWB will be 2030 or so (if even).

Only time will tell. But smaller BWB's wil not have some of the issues that a larger one would have. 20 - 30% fuel saving with increased rang and payload will make a BWB a hard thing to pass up for an airliner.

YouTube - X-48B 10 sec. clip (Take off)




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[edit on 13/11/2007 by Mirthful Me]

Evacuation must be a challage on 1,000 passenager version of one of these. The requirements is to empty the plane in 90 seconds with only half of the doors on the plane used.

The A380 has 16 doors, so for one of these I guess you would need 20. Not sure where you put them. I wouldn't give you much chance if you was in the middle.

The full size model has escape provisions all along the back edge, and on both sides/forward leading edge. You can also place escap hatches on the top and bottom.

All early simulation show no problems in this area. Evacuation will be just fine.




Note: Item 11 in picture, and leading edge surface access on the dark blue area (Item 13)

You could place 3 to 4 on either side and the entire aft end.

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[edit on 13/11/2007 by Mirthful Me]

NASA Video Released!

Originally posted by MrKnight
All you are looking at is the outside design, but you are not taking intoconsideration all the the internal structure, and all of the control surfaces and parts that go into a tail of an aircraft.

No, I AM thinking of the interior structural design - you are focusing totally on the aerodynamics.

Originally posted by MrKnight
The body of a BWB will not be any differnet to make than having differnt types of molds for the upper and lower surfaces, alomse of flat surfecs with slight bends in them. Then they will be put together over a very simple frame.

A very simple frame?

Yet again, your assuming simplicity where it doesn't exist.

Originally posted by MrKnight
Dr. Liebeck has also stated the preliminary desings show that around 30% fewer parts will be required. I have heard him state similar thing in recent siminars.

"The plane also would require about 30 percent fewer parts to make and emit less noise and pollution, Liebeck said. Another advantage is that the design can be easily scaled so that a plane could be made seating as few as 200 passengers or as many as 800."

Yes, and his studies assumed that a competitive (compared to conventional cylinder) technique of constructing the pressure hull would be available. Otherwise, the conventional cigar/wings is still the best choice - read it, thats what is said in HIS journal papers on the subject.


The plane cannot be easily scaled. I don't know why he said that.

Originally posted by MrKnight
Every new aircraft takes billions to develop. But I doubt that a small blended wing will cost as much as the B787 and A380 together.

You really don't understand the scale of the problem then.

Originally posted by MrKnight
I have seen reports that both the A380 and 787 have each cost between 10 to 15 Billionto develop. A 200 Passenager sized commercial cargo / millitary freighter would not take 30 Billion to develop. I would put the cost for a C-130 sized military / commercial freighter at 3 to 5 billion.

What on earth gives you the idea that it won't cost thats to develop?

The C-17 cost cira $40 billion USD to develop and get 120 of them built.

Originally posted by MrKnight
A very attractive risk for that particular market given future trends for military replamcement market ofr that size, and the fuel saving of a BWB for a commerical freighter.

I suggest you look at a direct operating costs diagram of any modern aircraft & airline.

Sinking billions into developing the technology is no use if it rises the DOC purchasing costs by 50%, but gives a fuel savings of 20% over the life of the plane.

Originally posted by MrKnight
Please give a round of applause for "Captain Obvious"! Of course that is what is going on. This would not be going on if Boeing was not serious, and if the potential customers were not taking it into consideration.

These kind of studies go on all the time - there are many more we aren't aware of.

There have been feasibility studies for space tourism carried out... doesn't mean we'll have hotels in space inside 20 years either.

Originally posted by MrKnight
Only time will tell. But smaller BWB's wil not have some of the issues that a larger one would have. 20 - 30% fuel saving with increased rang and payload will make a BWB a hard thing to pass up for an airliner.

Not if it costs twice as much to buy.

Also, there won't be a 20-30% fuel saving until the structural issues are sorted, and there won't be a commercial version until the FAA/JAA are happy.

Interesting.

I have a question, how fast can it go? What's the max speed?

Could you provide me details such as speed, weight, etc. in list? Thanks!

Originally posted by TheoOne
Interesting.

I have a question, how fast can it go? What's the max speed?

Could you provide me details such as speed, weight, etc. in list? Thanks!

For the model?

The X-48B's three turbojet engines will allow the 500-pound, composite-skinned, 21-foot wingspan prototype to fly up to 120 knots and 10,000 feet in altitude during flight testing.

An actual design is still ages away, so there are no weight/speed estimations available etc

[edit on 29/10/07 by kilcoo316]

Originally posted by MrKnight

Keep in mind that this is with the larger version. As you can see it is only about half as long, so it will take up less hanger and ramp sapce.

Hanger space is not an issue (a commercial aircraft spends as little time in a hanger as possible during its life) and ramp space is primarily dictated by wingspan and not length.

Originally posted by MrKnight
The full size model has escape provisions all along the back edge, and on both sides/forward leading edge. You can also place escap hatches on the top and bottom.

All early simulation show no problems in this area. Evacuation will be just fine.




Note: Item 11 in picture, and leading edge surface access on the dark blue area (Item 13)

You could place 3 to 4 on either side and the entire aft end.

None of those would pass the current FAA FAR Part 25 requirements, the aircraft would not be certified for civilian passenger use.

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[edit on 13/11/2007 by Mirthful Me]

Originally posted by RichardPrice
None of those would pass the current FAA FAR Part 25 requirements, the aircraft would not be certified for civilian passenger use.

Please quote the section of the regulation that you feel conflicts with exits placed in that area? All you have to do is place a hatch with inflatable slides and they would be no differnt than the main entery door emergency exit use.

FAA FAR Part 25 Section 803 Emergency Evacuation states:
"a) Each crew and passenger area must have emergency means to allow rapid evacuation in crash landings, with the landing gear extended as well as with the landing gear retracted, considering the possibility of the airplane being on fire.

(b) [Reserved]

(c) For airplanes having a seating capacity of more than 44 passengers, it must be shown that the maximum seating capacity, including the number of crewmembers required by the operating rules for which certification is requested, can be evacuated from the airplane to the ground under simulated emergency conditions within 90 seconds. Compliance with this requirement must be shown by actual demonstration using the test criteria outlined in appendix J of this part unless the Administrator finds that a combination of analysis and testing will provide data equivalent to that which would be obtained by actual demonstration. "

(d)-(e) [Reserved]

FAR 25 Appendix J

FAA FAR 25 Section 807

Subsection (f)(4) states:
"(4) For an airplane that is required to have more than one passenger emergency exit for each side of the fuselage, no passenger emergency exit shall be more than 60 feet from any adjacent passenger emergency exit on the same side of the same deck of the fuselage, as measured parallel to the airplane's longitudinal axis between the nearest exit edges."

Given the large number of passenger, several exit will be required on either side. The 60 feet rule may get a little questionable, but if enough aft exits are avaliable, and everyone can get out per the requirements, the FAA can grant exemptions. They are aware that the regulations are mostly written for traditional aircraft, and this being a differnt design might have to require some thought.

That is why they leave section 'Reserved" as they understand that additional conditions may lead to rule changes in the future.

Please be more specific on what part of FAA FAR Part 25 will not pass approval. I provided links to Part 25 above and would appreciate something more specific. Part 25 covers many things. Next time try to at least list the subsection, and quote what is not in compliance.

Also, the first few BWB's will be freighters and military aircraft. Once airliners see the performance, low fuel and operational cost you will see BWB passenger aircraft.

People use to state safty issues as to why the jet engine would never be used on a commercial aircraft. Oh how time changs things.

[edit on 13-11-2007 by MrKnight]