1. A method for operating a network data processing system on an aircraft comprising: performing a number of operations in a virtual machine on the aircraft, wherein the virtual machine runs on a processor unit in the network data processing system on the aircraft to create a simulated computer environment and wherein the virtual machine accesses resources of the processor unit for performing the number of operations using a host operating system on the processor unit; identifying, by the network data processing system, a change in a current state of the aircraft, wherein identifying the change in the current state of the aircraft comprises identifying at least one of a change in a phase of flight of the aircraft, a change in a location of the aircraft, a change in engine conditions, a change in cabin conditions, and a change in conditions outside of the aircraft; managing the running of the virtual machine responsive to and based on the change in the current state of the aircraft and based on a policy for managing the virtual machine for different states of the aircraft; and wherein managing the running of the virtual machine comprises, responsive to identifying the current state of the aircraft as a first state and based on a policy for not running the virtual machine for the first state, stopping the virtual machine without stopping the host operating system and starting the virtual machine responsive to identifying the current state of the aircraft as a second state and based on a policy for running the virtual machine for the second state.