More cracks in scarebus wings

[saggs]

How many composite airplanes will be flying around in 40 years?

A lot.  What do you want to bet?

There are a couple of Starships (all composite, and early composite technology at that) still flying going on 28 years now, no problems.  (well, what I mean is the Starships problems have nothing to do with composite construction)  There are a lot of Vikings with wood wings still going strong after 40+ years too.

All the things you're saying about composites Tupac, are the same thing some folks said many decades ago when most went from wood or steel tube and fabric to aluminum construction.

[Tupac]

So please stop with the insinuations that European engineers can't be trusted.

Where did I say European engineers can't be trusted? I said nothing of the sort.

[Tupac]

A lot.  What do you want to bet?

There are a couple of Starships (all composite, and early composite technology at that) still flying going on 28 years now, no problems.  (well, what I mean is the Starships problems have nothing to do with composite construction)  There are a lot of Vikings with wood wings still going strong after 40+ years too.

All the things you're saying about composites Tupac, are the same thing some folks said many decades ago when most went from wood or steel tube and fabric to aluminum construction.

I've had the pleasure of flying in a super viking. Bellanca makes a great product.

[Tupac]

I've had the pleasure of flying in a super viking. Bellanca makes a great product.

Parts really do grow on trees for that plane 

[nrshida]

I work with composites for some of my projects, just off the top of my head, so don't nitpick or quote me on this, if the composite part is carefully designed to suit the attributes of that material (and not as a substitution for another material without redesign) then it can be up to sixteen times stronger for the same mass as a steel part, or the same strength and up to the same magnitude lighter. It is impervious to corrosion, absorbs vibration much better than aluminium alloy and Titanium alloy parts, is more docile to thermal cycling and so on. There is also the potential to use less seams and joints such as in the wing for the Boeing X-32 for example. As a designer you want to do this as much as possible.

It is hardly objective to compare a new material technology with one which has been employed for far longer. Obviously it takes time to understand how to use it effectively and reliably. The advantages offered cannot be ignored. Follow the development of the version of the Harrier used by the US Marines for an example. Compare the payload and dry weight figures against the GR.1.

[MachFly]

Now not to knock Cirrus or Diamond they both make an incredibly fine product and I have no doubt some of them will be flying a long ways down the road, but they aren't subject to the incredible weights that the A380 incurs. I just hope the 787 doesn't run into problems.

F-22 has a large amount of composite parts, yes it's not that heavy but when it pulls Gs it becomes a lot heavier. MXS is completely made out of composites and is rated for 14Gs. Composite materials work fine under a lot of weight. I think if A380 was made out of metal it would still have problems, just different ones.

[MachFly]

A lot.  What do you want to bet?

  There are fully composite aircraft that are over 40 years old? Which ones?

[nrshida]

How about the Mosquito?

[MachFly]

post deleted

(should have originally made it more specific)

[nrshida]

No it's a composite of wood and glue, the grain of the wood changing direction in layers. If you ever have the opportunity to work with CFRP you see how similar the principal is. The astounding thing about composites is that you get the advantages of both of the materials being used.

[saggs]

 I will gladly fly any Beech, Cessna, Cirrus, Diamond, Fairchild, Aeronca, American Champion, Piper, Rockwell, Bellanca, Flight Design, Grumman, Jabiru, Lancair, etc

You see Tupac, this is where you go wrong.  From the mechanics viewpoint that I have, I can tell you that there are some 1960 172s I wouldn't hesitate to fly, and other 1960 172s I wouldn't dream of flying in.  You know this... it's all about how well maintained they are.

The same thing holds true with the big boys on the commercial side.  There are some CRJs operated by carrier "A" I fly in all the time.  However there is another carrier "B" which also operates CRJs and I don't think I'd ever fly with them because I've seen firsthand how sloppy their maintenance/repair work is.

In almost every case of catastrophic failure caused by mechanical or structural failure, it is not the fault of the design, or original manufacture of the aircraft.  It is almost always a maintenance issue.  The biggest one in my mind is the Alaska Air MD-80 that augered into the pacific because they decided lubing the HS jackscrew was to time consuming and they only did it 1/3 as often as the manufacturer recommended.  Does that mean MD-80s are unsafe???  It wasn't MDs fault, it was the fault of Alaska Air's poor maintenance program.

There isn't a single commercially operated plane out there that I think is an unsafe design, but there are probably a few unsafe planes.  It all comes down to maintenance, and in this case Airbus, EASA, and the FAA seem to be on it.

[Rob52240]

Remember this composite Beauty?



http://www.youtube.com/watch?v=1vSiiE2cyuc

[saggs]

There are fully composite aircraft that are over 40 years old? Which ones?

You misunderstand, Tupac said "How many would be flying 40 yrs from now?" I answered a lot.

That's wood, composite is basically plastic.

Nope, technically plywood is a composite.  Though in modern jargon "composite" is usually taken to mean, carbon fiber, fiberglass, kevlar etc..

The term composite refers to anything that is made up of 2 or more different materials, in such a manner as to take advantage of the strengths of both creating a product that is much stronger then the 2 separately.  These 2 different materials are usually referred to as the matrix and the reinforcement.  In the case of plywood, the glue is the matrix, and the thin sheets of wood are the reinforcement.  In the case of more modern composites like fiberglass or carbon fiber the cloth is the reinforcement and the resin is the matrix and in planes they usually throw some aluminum or nomex honeycomb in the middle too.  Technically dope and fabric is a composite as well.

[MachFly]

No it's a composite of wood and glue, the grain of the wood changing direction in layers. If you ever have the opportunity to work with CFRP you see how similar the principal is. The astounding thing about composites is that you get the advantages of both of the materials being used.

Nope, technically plywood is a composite.  Though in modern jargon "composite" is usually taken to mean, carbon fiber, fiberglass, kevlar etc..

The term composite refers to anything that is made up of 2 or more different materials, in such a manner as to take advantage of the strengths of both creating a product that is much stronger then the 2 separately.  These 2 different materials are usually referred to as the matrix and the reinforcement.  In the case of plywood, the glue is the matrix, and the thin sheets of wood are the reinforcement.  In the case of more modern composites like fiberglass or carbon fiber the cloth is the reinforcement and the resin is the matrix.  Technically dope and fabric is a composite as well.

Right. Composite is a rather broad description. My point was that wooden aircraft don't really count, as modern aircraft that are build out of composites do not involve wood.

[saggs]

Remember this composite Beauty?

(Image removed from quote.)

http://www.youtube.com/watch?v=1vSiiE2cyuc

Yep, I took a nap in one last week.    (sadly it hasn't flown for many years and never will again  )