What is aircraft plywood? What is it used for?

Question

I was looking at boomerangs and ran across the term "aircraft plywood". Going further they just seem to be talking about spruce as in "spruce goose".

Does the term "aircraft plywood" have any special significance, use, or connotation for woodworkers. Is it of a higher quality than regular spruce?

What is aircraft plywood? What is it used for?

Answer 1

From Wikipedia:

Aircraft plywood

High-strength plywood also known as aircraft plywood, is made from mahogany and/or birch, and uses adhesives with increased resistance to heat and humidity. It was used for several World War II fighter aircraft. Although the British-built Mosquito bomber, nicknamed "The Wooden Wonder", was constructed of a plywood monocoque, this was formed in moulds from individual veneers of birch, balsa and birch, rather than machined from pre-laminated plywood sheets.

Structural aircraft-grade plywood is more commonly manufactured from African mahogany or American birch veneers that are bonded together in a hot press over hardwood cores of basswood or poplar or from European Birch veneers throughout. Basswood is another type of aviation-grade plywood that is lighter and more flexible than mahogany and birch plywood but has slightly less structural strength. Aviation-grade plywood is manufactured to a number of specifications including those outlined since 1931 in the Germanischer Lloyd Rules for Surveying and Testing of Plywood for Aircraft and MIL-P-607, the latter of which calls for shear testing after immersion in boiling water for three hours to verify the adhesive qualities between the plies and meets specifications.

Answer 2

What is it used for?

Well, it certainly is not used only for airplanes.

This from an aircraft plywood manufacturer:

As the name indicates aircraft plywood is used in the manufacture of aircraft but also boats, furniture, model airplanes, model boats, doll houses, boomerangs and other toys, musical instruments, fine packaging (e.g. cigar cases) including food packaging (e.g. chocolate boxes).

To be used for aircraft it must be high quality which makes it desirable for other applications. One of its desired attributes is, like all plywood, dimensional stability parallel to the surface. Its dimensional stability for thickness suffers like any other wood.