Air force engineers have created transparent aluminum for use in wargrade military construction where extravehicular vision is required. This new material is highly resistant to scratches and can withstand more damage then conventional designs that use multilayered glass which is twice as heavy. Though equal amounts of transparent aluminum currently cost upto 5x more than multi-layered glass, proponents of transparent aluminum point out that savings will be achieved over the long term,

"It might cost more in the beginning, but it is going to cost less in the
long run because you are going to have to replace it less,"

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