Fuse pin

[feajob]

Hello, We need to design a fuse pin for a main landing gear. The goal is to achieve controlled shear failure to protect the aircraft. Our focus is on achieving a predictable failure in shear mode rather than tension or bending, as shear failure provides more controlled separation. To control the failure location, internal or external grooves (or notches) can be incorporated. I am interested in your insights on this matter: would you recommend using an internal or external groove design for the fuse pin, and why? Thanks, AAY

 

[SWComposites]

External is way easier to fabricate and inspect in service.

Note, design of fuse pins is not easy. And you cannot rely solely on FEA. You must test them.

 

[rb1957]

I've done this before. It requires a lot of testing (to match the specific strength of the lot to the required failure load ... depending on your tolerance for failure load).

An internal grove ?? sounds way (sorry, Way) harder to produce than an external grove. Failure should be evident (and not need inspection). You may need inspection to check for corrosion or other damage.

Many landing gear already use this design ... go have a look at one, find what engineering data you can. I suspect there are papers written on this (like for trade conferences).