The B-58 Hustler escape capsule is probably the best operational example of this. It allowed pilots to eject at speeds up to Mach 2 (!!).
theaviationist.com/2015/03/17/sr-71-mid-air-disintegration/
https://www.youtube.com/watch?v=M8l79lSjVMg http://www.f-111.net/ejection.htm