A term used in military pilot slang, essentially meaning "I'm a friendly". After being locked on by a friendly craft, modern RWR gives out a distinct tone. "Buddy spike" is used to quickly inform the other pilot he has locked onto a friendly craft.

A typical exchange would be:

Viper 8 locks onto Viper 12

Viper 8: "Viper 8, Raygun, bullseye 190 for 80"

Viper 12 realizes he is at the called position

Viper 12: "Viper 12, buddy spike"