Websites... regarding lightweight design principles 3

[Garvin]

I hope this is the right forum to ask this question....

I have been seeking all over the net (and this forum)for information regarding lightweight design principles regarding aerostructures, but so far with very little luck.
Maybe because "lightweight design" is basically the wrong
expression to search for.... Is it?
I'm danish, and not all into the english/american words used in this field.

Does anyone here have some links to good sites with general basic information regarding "subject".

Hope someone can help me out with this.... thanks



Regards,
Jan L

 

[Compositepro]

There are many different approaches to light weight design. Selecting an approach involves many trade-offs between cost, complexity, materials of construction, manufacturability, durability, etc. Since aircraft are always weight sensitive you may have better results researching aircraft structural design.

Light weight design approaches include honeycomb or foam sandwich structure, skin and stringer, isogrid, tubular truss or space frame, and monocoque construction. Use these for search terms.

 

[Garvin]

Thank you !!!

It's hard to look for something on the internet, if you don't know what it's called... ;-)




Best regards,
Jan L

 

[Sparweb]

Garvin,

Let's try to narrow down what you're looking for. Are you looking for,

a) light aircraft materials,
b) light airplanes, or
c) guidance on where to put the lightening holes in the spar of your homebuilt?



STF

 

[Garvin]

Well... actually a little of it all..

The reason is that I'm applying for a job, where I would have to work with substructures for helicopters and aircrafts, but I have not worked with it before, so I wan't to prepare myself for a jobinterview.

I have worked with FEM for two years with different kinds of shell- and beam structures, as a consulting engineer within the oil-business. I'm sure that I can use my education and general understanding of FEM, within this new area, which I find very interesting, but unfortunately the demands for aircrafts is not exactly the same as for oil-rigs and equipment used on them...
Maybe except that there are very high standards regarding safety precautions and the likes.


Best regards,
Jan L

 

[Sparweb]

I would suggest that a web-search is not the source of information you need. You need to talk to other people in the industry to get a "feel" for how they approach problems. You should also invest in the more common aircraft structures textbooks, even the ones that don't have anything to do with FEM, such as Bruhn or Niu's textbooks. The weight of the structure is only one piece of a bigger puzzle, and you don't want to learn about it out of context.

If the interview is coming soon, then the only advantage the web will have is speed of availability, not in reliability.

The aircraft business is regulated in its own unique way, too, and that might or might not have an impact on the understanding you need to develop.


STF

 

[Bidonro]

Garvin, the industry term is "Weight Optimization," and you will not find much material on the Internet. In the case of structures, it is the effective selection of materials, effective use of shape (stiffness), minimum effective margins of safety, and the application of manufacturing processes that allow design of section properties for applied loads rather than process limitations.

In Aerospace, the experts are known as "weights engineers" or "mass properties engineers." They have a society known as the Society of Allied Weights Engineers.

In aircraft, vehicle primary structures typically have efficient mass properties. It has been my experience that avionics packaging and secondary structures have the least efficient mass properties. There is almost no weight optimization information available for avionics packaging.

Consider this scenario. A military electronic warfare aircraft has an empty weight of 49,000 lbs of which 16,000 lbs is primary structure, and 35,000 lbs is avionics. It is obvious that the propensity for weight optimization opportunities (weight reduction) is in the avionics.

Bob B
Manager
Mass Properties & Specialty Engineering

 

[Garvin]

Hi !!!

i'm sorry I haven't replied before now, but I have been very busy lately with work, so I haven't had the opportunity to get my PC powered up... :-(

I thank you all for the nice response, and I have managed to find some material on the net regarding weight optimization in general.

- SparWeb -
Well, I was going for "Speed of availability" as I don't now anyone personally within the industry.

- Bidonro -
I thank you for the clarification regarding the industry terms. As I mentioned further up, it is very difficult to search the internet for something, if you don't know what it is called.


Unfortunately I did not get the job, as it went to a newly graduated engineer, which I know a little. But I surely appreciate your help, And I'm sure it will come in handy for my further job applications.

Kind regards,
Jan L

Best regards,
Jan L