Abstract: A tactical missile includes a heat pipe connecting heat sources with heat sinks within the missile. The system includes a removable external heat dissipation device that connects to the heat pipe while the missile is being tested or reprogrammed. The external heat dissipation device draws heat out of the heat pipe and so maintains the electronic components acceptably cool during extended testing or reprogramming. During the relatively short tactical flight, the heat pipe transfers heat from the electronic components to the heat sinks within the missile. The high heat transfer rate of the heat pipe enables elements such as structural members and propellant to be used as heat sinks, elements not heretofore incorporated into thermal management of the heat generating electronic components.