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  (Source: Boeing)

  (Source: Boeing)
Boeing glides along with Dreamliner development

Boeing has a lot riding on its 787 Dreamliner program, and after a two-year delay, things appear to be panning out nicely for the Seattle-based company. The first 787 Dreamliner made its maiden flight on December 15, 2009 and stayed aloft for roughly three hours.

The second 787 Dreamliner took to the air a week later featuring the markings of the first customer which will receive the new planes: All Nippon Airways (ANA). In total, 15 flights (totaling nearly 60 hours) have been made so far using the first two aircraft.

Another milestone was reached late last week; the 787 Dreamliner achieved "initial airworthiness" status. This milestone allows Boeing to open up the testing phase to more aircraft. Boeing flight engineers will also be allowed on the flight deck now according to the Associated Press.

"This is an important step forward," said Boeing Commercial Airplanes VP Scott Fancher. "We are very pleased with the results we have achieved so far. The airplane has been performing as we expected."

The previous test flights have seen the 787 Dreamliners reach a top speed of Mach 0.65 and an altitude of 30,000 feet. In the coming weeks, Boeing test pilots will take the aircraft to Mach 0.85+ and in excess of 40,000 feet.

"The pilots have told me the results we are seeing in flight match their expectations and the simulations we've run. That's a real tribute to Boeing's expertise and the international team that helped develop and build the airplane," Fancher added.

ANA is expected to receive its first 787 Dreamliners during the fourth quarter of 2010. The Japanese airliner has ordered 55 of the aircraft.



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RE: Conventional looking now
By Kurz on 1/19/2010 9:22:21 AM , Rating: -1
Composite sounds so nice even though its basically a plastic. Sounds strong and flexible.

Plastic is usually designated for inferior plastics which change color or are brittle and strength wise is inferior.

Thats why they make the distinction.


RE: Conventional looking now
By theapparition on 1/19/2010 12:00:57 PM , Rating: 4
Plastics and composites are not the same thing. The definition of composite is using 2 or more materials (composite). A typical composite uses a base material surrounded by a epoxy matrix.

Talking about generalizations, when you say plastics, it's generally thought of as injection molded (or blow molded). Yes, there are other methods, and not all plastics are thermoplastics either, but close enough. Melted plastic pellets are pushed under high pressure into mold cavities to form a part.

Composites on the other hand, generally speaking, refer to hand made layups that orient the fiber of the base prepreg in the direction of interest. They have to specially cured usually under pressure. They can't be mass manufactured, can't be injected, and have signifigantly better strength to weight ratios than other competing materials.

Yes, you can add fillers to conventional IM plastics such as fiberglass, steel (wool), and many others. However, even though they fit the technical description of composites, they are generally not considered as such. The science of composite engineering is actually quite difficult since they have rather non-linear material properties. For example, in a typical carbon fiber body, the tensile strength comes almost exclusively from the carbon fiber, but it's compressive strength comes from it's matrix material.

Base materials for most composites are either fiberglass, carbon fiber or Kevlar. All three materials are actually classified as ceramics. So techically, they are most commonly a ceramic-plastic composition of 2 materials. Instead, the industry chooses the term "composite".

However, your assumption of them being anywhere remotely close to being the same is incorrect.


RE: Conventional looking now
By 91TTZ on 1/19/2010 12:42:32 PM , Rating: 2
quote:
Composites on the other hand, generally speaking, refer to hand made layups that orient the fiber of the base prepreg in the direction of interest. They have to specially cured usually under pressure. They can't be mass manufactured, can't be injected, and have signifigantly better strength to weight ratios than other competing materials.


This isn't accurate. You can definitely mass produce composite parts. Tennis rackets, fishing poles, tent poles, RC car chassis, surf boards, boats, and various other things are commonly mass produced and made of composite materials.

The reason you see composites being made by hand so often is because it's very workable and lends itself to that type of work. While a worker isn't going to be able to bend a plate of titanium with his bare hands he can easily cut and lay carbon fiber fabric in a mold and apply resin to it.


RE: Conventional looking now
By theapparition on 1/20/2010 8:15:15 AM , Rating: 1
Again, I was talking in generalizations and in context of aircraft manufacture. I thought I made that clear.

Some things, particuarly fiberglass, can be made by more conventional means. Keep in mind though, the round objects are manufactured by spin weaving composite threads. The other objects you mentioned (and as I mentioned) are technically composite, but are not continuous weave fabrics. So while they have some of the benefits of composites due to scrim reinforcement, those manufacturing processes would in no way be acceptable for airframe manufacture.

Your hypothetical manufacturing enviroment is not anywhere close to being correct either. Cheap fiberglass work does not equal carbon fiber or kevlar manufacture. You need an autoclave to properly cure the resin under pressure to eliminate voids. Why you see people doing hand layups is simple, because they don't have too many machines that can take the fiber and properly orient and apply in a custom situation. They do have machines that cut the fiber in the propper pattern. But actual assembly is still mainly a hand operation, especially in a custom enviroment.

BTW, a stamping machine to form metal is far cheaper in the long run than a team of skilled composite technicians.


RE: Conventional looking now
By drewidgho5t on 1/20/2010 3:06:33 PM , Rating: 1
@ theapparition

in defense of you I would like to tell 91ttz to STFU. Try learning instead of arguing.

@ 91ttz Those "mass produced parts" you speak of are usually fab'd as FRP--fibre re-inforced polymers. There is very little control regarding the orientation of the fibres. They are dumped into a big batch of molten polymer.

theapparition was kind enough to share knowledge with us, you included. You are rude enough to argue the minute details of semantics. See the part about additives-steel wool, fibreglass, etc??

Read the part where theapparition breaks down the difference in terminology. Resin impregnated fibre cloth is almost always laid by hand. That is how the fibre orientation is assured.

What a shame that the concept needs to be explained TWICE.

@theapparition--your explanation of terminology is eloquent and accurate. Just tell 91 titties to STFU and go rub some of his 91nplz.


RE: Conventional looking now
By 91TTZ on 1/20/2010 4:09:34 PM , Rating: 3
Wow, you seem overly upset over a non-issue.

The apparition was able to explain his case clearly while you come across as being an emotional 15 year old whose mom just took his XBox.


RE: Conventional looking now
By drewidgho5t on 1/20/2010 10:37:12 PM , Rating: 1
So if the case was explained clearly why did you attempt to find an inconsistency with what theapparition posted? CLEARLY, you chose to find whatever point you thought could be argued and emphasize the innaccuracy.

That is much more indicative of "the 15yr old" than someone berating a man-child for choosing to ignore an exceptionally informative post. Getting upset over nothing? No, I got upset over you choosing to argue instead of learn. Now STFU, read and learn.

BTW, have you noticed that none of the other clearly knowledgable people in this field have taken the same position as you.

theapparition did you (and me) a favour and you took a pass. You sure you want to discuss who is coming across as a 15 yr old?


RE: Conventional looking now
By 91TTZ on 1/21/2010 9:03:09 AM , Rating: 2
You clearly behave like an adolescent. You were either beaten up too much as a child or maybe you weren't beaten up enough. I'm not really sure.


RE: Conventional looking now
By 91TTZ on 1/19/2010 12:36:25 PM , Rating: 4
Composites are slightly different than pure plastics. A composite is a, well, composite of a stiff fabric and a plastic binder. If you made a part of only plastic it would be plastic. If that part was fiberglass or carbon fiber binded together with plastic, it would be a composite.


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