Designing space hardware is hard [video]

One of my favorite pitfalls in aero is connector mating lifetimes. Any time there is a connector (like a good old-fashioned DB-9), there are metals in the contacts that will have a pressure-based interface (pin inserting into hole). High-ductility metals (copper, gold, etc. that are typically used for connectors) like to become brittle after getting bent around a bit. Unfortunately, when the individual conductors become more brittle, their stiffness goes down, and this results in the connector performing poorly on vibes. This is because the resonant properties of the individual pins within a connector are tuned to not have micro-disconnects during the vibration of launch - they are sufficiently stiff to withstand the forces. This tuning is a function of the number of times it has been connected and disconnected because of the embrittlement, so each connector has a "mating lifetime" on the order of 10 mates/demates before you have to scrap it. This means your flight electrical connectors are really, really important. I remember being a young naive engineer and being shocked and appalled by the waste.

[1]: https://ntrs.nasa.gov/api/citations/19900004959/downloads/19...