NJ.

“Advanced aluminium alloys” can be found on the 747 primary structure. That can range from ordinary advanced 7050 or 7075 ally to the Sandwiches.

It is with your great dissapointment,
I have no need for ointment,
The colgate product mistaken
Was an acid after shaken
But Milk was mixed
Full fat and no tricks.

Don’t worry, it’s no worse that mate phoning me from A&E,

It appears that the new dyson ball cleaner wasn’t quite what he thought it was 😀

Man in hospital with a Hoover nozzle stuck up the bum.
Whilst he was waiting for the operation, nurse said he was picking up very well.

You didn’t directly answer the question, PeeDee. Again, if composites are so bad then why are manufacturers with decades of experience building aircraft not aware of it? Are you essentially saying they know the materials are flawed but they dare not backtrack now?

I am. Yes.
The materials are not flawed, the application of them is. It’s too soon.
The calcs all suggest it will be fine. I don’t believe the calcs until real figures are put into the creation of the algorithm. We are now getting real figures from A400 and 787. But obviously, Boeing aren’t telling Airbus and Airbus aren’t telling Boeing. Airbus military aren’t even telling Airbus civil! And nobody is telling Bombardier!
The amount of extra metalwork that is having to be put on these parts, to assist (Not remove) some of the problems I have highlighted makes a mockery of the weight savings.

PeeDee, please answer me one question. If using composites is such a bad thing as you suggest, why are Airbus, Boeing and other manufacturers strangely unaware of it?

Using composites is an excellent thing, for Panels and niff naff doors and such.
I’m talking primary airliner structure.
AUK, A400 Military, Boeing, Bombardier are totally aware of it. And are all suffering it, the lab tests say it’s OK.
787 had to strengthen (By thickening) the class 1 items in the Wing Box, because, quite simply, the claims of strength vs weight calculations were wrong.
Embraer could have gone plastic, they watched and listened…stuck to metal.
Kawasaki did CFRP parts for Boeing, when it came to making their own (C2 I think)…..metal. They’d learnt.
I deal with all the big OEM’s, and my comments are drawn from their experiences. All the players are over confident with the genuine risks involved. The above points are all valid, the only one that is improving is the repairs in service – devlopments on out-of-autoclave curing enables Billy-Bob in the shed to mend it.

As I said, the market has changed a bit, the same savings required can now be drawn from fantastic engines, superb wing planforms and general weight cuts. More use, experience and knowledge should be gained by developing the sandwich metals such as GLARE.
If the main players were to start afresh, right now….they would not go for plastic. But they dare not back out now as they’ve spent so much.
Even based on cost, they cost a fortune to build, the tooling costs a fortune and so does the design. Even the machines that lay CFRP tape down cannot lay as fast as needed, and need too many manual interruptions.
They have all jumped on a bandwaggon, and that waggon has changed course.
The Airlines are not demanding plastic, they are demanding economy because fuel is the driver. As I said, the same economy can be gained elsewhere on the platform.

Oh! How ungallant of you, PeeDee!

Margaret Lake (aka Mystic Meg) was born in Accrington in 1952.

Interestingly, she graduated in English at Leeds University and owns a string of racehorses.

Also, a work colleague of mine used to clean her windows.

Small world, isn’t it?

I’ll have a pint of whatever you’re on.:diablo:

Well, it won’t be colgate plax.
I was naked at Glasto. But I was as muddy as Rambo so only those that knew me could tell.

You will be delighted to learn that I once observed a sign worded almost identically outside the tent of a so-called ‘psychic’ at Glastonbury.

I laughed so much, I almost disgraced myself. 😀

Which is not hard to do when you are already naked.