Abstract: An air-to-ground telecommunications system allows callers to store messages on an aircraft data server when sufficient air-to-ground communication bandwidth is unavailable for transmitting a call. The system allows aircraft callers to leave voice, fax, e-mail or other data messages. The messages are stored on the aircraft until sufficient bandwidth becomes available for transmission to the ground. Transmitting messages requires shorter air time and more efficient bandwidth usage because messages do not require a high degree of interaction between parties. The messages can also be compressed before transmission for further efficiently using aircraft-to-ground bandwidth.