Do you know they used lead free solder? Military, medical and other high risk products do not have to use lead free solder.Interesting to hear.
For the last part of my working life I was an ROV senior pilot/tech. The ROVs operated in very hostile environments etc and not once did we have a failure due to solder related issues.
I’ll have to read up, every day a school day.
Thanks
Those industries lobbied hard for that exclusion