I was watching something about blended wing designs not long ago. Apparently the biggest problem with them right now is that they'll have to learn a whole new way to make turns and other manuvers. With a standard round fuselage, everyone is near the center of rotation, so when the plane turns, you don't notice the angle of bank as much, whereas with the blended wing design, you some people will be sitting way out from the center of rotation, so they will have trays, drinks, people sliding around as they bank. Apparently they are working on developing ways to make level turns to resolve this problem.

Nullster.

ahh, your one of those lightwave guys...I was interested in that a couple weeks ago...just for a hobby. I tried out Lightwave / modo / Rhino / and a couple others I cant think of right now, I kept switching hoping the next one would be easier...then I just gave up, its a lot harder then I thought.

I don't get how this was "unveiled" since it was a known concept for over 10 years. The aircraft they show is the Boeing Blended Wing Body (BWB), which was first shown as this particular design late in 2004.

About the lack of window seats in a design like this. I've always thought it would be sweet to have LCD screens on the back of every seat (which they are doing now) and to have cameras installed on the outside of differnt parts of the plane. Like say one looking forward, one aft and one looking down and another up. Then you could pick whatever view you'd like to watch. Personally I think it would be sweet. Especially being able to see what's directly ahead. Plus take offs and landings would be neat to see from that point of view, (although that might scare some people)

I think it's a great idea personally.

I also really like the BWB design for the comercial aircraft. Is Boeing still working on there's? I remember hearing about it a few years ago, but nothing really has seemed to develop from it.

EDIT: nullster, great model by the way. I could never really get into lightwave, but it can do some great stuff. I'm more of a 3dsMax guy myself.

[edit on 19-8-2005 by jra]

Sounds cool... It could be really good in warfare...

This Aircraft would be good for the people who live around airports & have to put up with the noise every time a plane takes off & lands. Plus people who live right under the flight paths

I think the design of the fuselage being blended into the wing dates back to Burnelli in the 1920s and 1930s. These are not quite BWB but they came close. Also this design would mean that they might not have to put fuel below the passengers, which anyone can say is definitely a good thing.

I've seen that design many times. However the claustrophobia factor seems to be a big deal. Unless it goes from Europe to Japan in 3 hours max. it will be very difficult to implement

Im afraid a 'silent' aircraft is still a long way away people.

I reckon it'll be 2020 before active noise control technology is mature enough to go onto the active fleet aircraft, then real reductions can be made. Although the algorithms still won't be fully up to speed, we can focus them on the engines BPF to cut the tonal noise, then there are other things that can be done with the engine to reduce the broadband noise signature.

However, on approach, the aerodynamic noise of the airframe is almost equal to that of the engines, so work on wing flap/slat intersections, as well as improving the aerodynamics of the undercarriage needs to be done.

A group of us did a feasibility study of lifting body aircraft with a crowd from TU Delft in holland a few years back, the concepts ranged from pretty much a flying fuselage to a fully BWB... after a trade-off guess what won? Yup, the conventional cigar with the 2 wings attached. The structural compromises needed for the BWB along with the certification issues kind of stop it dead in its tracks, the R&D needed along with the air-time needed to get it certified means its a very large obstacle for any airline manufacturer to take on.


But, I think rising fuel prices will become more of an issue to airlines and the general public (ticket prices) in the coming years, so noise may go onto the back burner a little.

I don't dislike that design, but there are few things that bug me.

1- I guess most passengers will be located in the widest portion of the aircraft, in a 12, 20, 36 seats abreast, what have you, with several aisles, so the problem is when you do a steep roll manoeuvre, if you are sitting outboard, you will end up going up or down rapidly, you quite don't have this when the fuselage of a conventional aircraft rotate.

2- In a conventional transport aircraft, there is often a section which is a pure cylinder, this design allow for creation of several stretch versions, at a minimal cost (you basically just add a plug or two close to the wing), this design will not allow that.

3- Evacuating this type of design in case of emergency, could be tricky.

4- No windows, maybe peoples are used to look at a screen, so maybe camera & LCD display will do the trick.

I like the whole BWB idea and would love for it to take flight. As far as Silent aircraft? Well, maybe civil, and even then that claim might be a stretch. I check it out. It would be nice to have a plane that people won't gripe about taking off and landing near residential areas. A lot of work has gone on over the years in terms of silent aircraft. One success story that pops to mind and predates the BWB by a long way was Lockheed's OY-3. It was used in Viet Nam and was a modified version of a powered glider. It used a wide chord wooden prop, which spinned slower and a muffler running down one side of the aircraft. The result was a two man spy plane that could cruise almost directly over the enemy's head at night without them hearing it. It worked and none were ever detected. Of course, on that note, maybe that's one of the reasons the BWB project stalled. They might be affraid it would be stealthy, and a nightmare for air traffic controls to keep track off. The LearFan had that problem. You'd wind up flying into a hillside and no one could warn you because they wouldn't be able to find you! Oops...

Originally posted by Kata
Just kinda curious what the survival rate on a crash in one of these things would be. Do you think better or worse than conventional airliners?

Originally posted by PopeyeFAFL
..Evacuating this type of design in case of emergency, could be tricky.

I would think it would be a tad worse because the fuel will probably still be kept largely in the wings and here, instead of the wings just being attached to the fuselage (where they could mercifully break off in a crash), you are now blended with the wing that has just exploded into a ball of fire.
There's also a large amount of seating space there and if you're smack in the center of the plane it might be tricky to get out before smoke inhalation/fire would get you.
Personally, I figure most planes crash catastrophically (i.e. nose-into-the-ground) anyways so I don't worry about it too much.

Originally posted by highgroundsys0p
I like the blended wing body - BWB. I wonder how bad they'd have to cut up the terminal gates? Some major airports are SO out of room even now.

Well, the major international airports are already going to have to do some major work to get the A380 in there so assuming Boeing can keep the wingspan around the same width, it shouldn't require much more effort. They'll just have to share gates like the 747 & 777 do.

Originally posted by Zaphod58
Apparently the biggest problem with them right now is that they'll have to learn a whole new way to make turns and other manuvers. With a standard round fuselage, everyone is near the center of rotation, so when the plane turns, you don't notice the angle of bank as much, whereas with the blended wing design, you some people will be sitting way out from the center of rotation, so they will have trays, drinks, people sliding around as they bank. Apparently they are working on developing ways to make level turns to resolve this problem.

Now this one kind of baffles me. Say a plane goes into a 15 degree bank. Wouldn't everyone along that axis still be at a 15 degree angle to the horizon regardless of where you where in relation to the center? So I guess I don't see why drinks and trays at the sides would slide around more than the center, but then I never took physics so feel free to correct me here
Regardless, there are two answers to that problem. Either pilots will have to plan out and execute thier turns much further out to reduce the banking, or Boeing can make it the first airliner with thrust-vectoring engines. Now that would be cool!

Originally posted by jra
About the lack of window seats in a design like this. I've always thought it would be sweet to have LCD screens on the back of every seat (which they are doing now)... Especially being able to see what's directly ahead. Plus take offs and landings would be neat to see from that point of view, (although that might scare some people)

I think that's why most of the airlines don't do it now: The fear factor.
I agree, jra, I think it would be cool too, but since they already don't show a nose-cam when they easily could, I doubt we'd see one in this design either.

Anyways those are my thoughts on the design. I think any leap from the boring 'tube with wings' is great but it'll be interesting to see if it will pan out given the hurdles of producing something that radical verses sticking with a formula that the airlines know works.

The closer you are to the center of the roll, the less it affects you. With a cylindrical design (757, 767, etc) no matter how many aisles you have, you are near the center of rotation for the fuselage, so while you notice the roll, you aren't as affected by it.

Take a picture of a modern day airliner, and draw a line down the center of it. The further out from that line you are, the greater the movement. Next time you're flying, when you go into a bank, look out at the wingtips. For YOU it doesn't feel like you've rolled very far, however the wingtip will be at a steeper angle compared to the horizon. The same thing will occure with a blended wing design. The people our towards the wingtips will move farther everytime the plane rolls, than the peolpe closer to the center of roll.

And no I'm not pulling this out of my. This is directly from the designers of the plane at Boeing. They were talking about the problems with the design, and that was their biggest issue.

Originally posted by Shades of Grey
Now this one kind of baffles me. Say a plane goes into a 15 degree bank. Wouldn't everyone along that axis still be at a 15 degree angle to the horizon regardless of where you where in relation to the center? So I guess I don't see why drinks and trays at the sides would slide around more than the center, but then I never took physics so feel free to correct me here

Imagine a see saw with a child at each end (representing the extremeties of a BWB cabin) and one in the middle (like being sat in a conventional fuselage). as it rocks (equivalent to an aeroplane banking) picture how much more movement the child at each end experiences compared to the gentle rocking of the one in the middle.

[edit on 30-9-2005 by waynos]

I get it now. It's not the angle of deflection itself that would make trays and glasses slide around, its the fact that to get to that point the people at the center would drop (or raise) mere inches while the people at the sides would move in feet in the same span of time.

Thanks for cluing me in guys!
I guess I was thinking that Zaphod meant that the people at the sides would somehow be at a different angle than the people near the center. That much I knew was wrong unless the plane could alter its shape. Now there's an idea!

[edit on 30-9-2005 by Shades of Grey]

On the topic of windows, if you can't have them, put some micro-camera's on the external fuselage and then put foldable LCD screeens on the inside, if windows comprimise the low sound, don't use windows. That would work for the floor as weell becuase you could have a look then turn it off.

Imagine the whole plain floor just being an mage of the ground, certainly make sure you buckle your seatbelts during flight.