U/c ground locks, history and research query

[Krystal n chips]

Possibly one of the more obscure queries posted on here, but, hopefully, some relevant facts may emerge.

In essence, I am trying to help a friend engaged in a research project regarding the introduction, development, material specs, design(s), loadings and overall history / origins of the humble u/c ground lock.

Not the most enticing of subjects I know, but, any reference material, guides, or indeed design knowledge would be appreciated please.

Also being posted on the AH and N forum.

Many thanks.

K n C

[Avtrician]

This is more of a "how long is a piece of string" question,
Undercarriage locks can be a simple pit pin, sleeves or rods. materials and specs can vary greatly. each and every aircraft,(with retractable under cart) has a different system