terrestrial flight telephone system

Also known as: TFTS

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Last updated

June 11, 2026

Quick Summary

The terrestrial flight telephone system (TFTS) is a type of airborne cellular system that allows passengers on commercial aircraft to make telephone calls to the public switched telephone network (PSTN). This system operates using digital modulation and utilizes specific frequency bands. Ground stations for TFTS need to be spaced relatively close together to ensure coverage across large areas like Europe.1

In contrast, mobile telephones, or cell phones, are portable devices that connect to telecommunications networks, typically through cellular systems. These systems divide geographic areas into smaller "cells," each served by a base station. This cellular design allows for frequency reuse, increasing efficiency and enabling service for a large number of users within a metropolitan area. Advances in technology have significantly reduced the size and weight of these devices over time.1

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Airborne cellular systems
…APC system known as the terrestrial flight telephone system (TFTS) in 1992. This system employs digital modulation methods and operates in the 1,670–1,675- and 1,800–1,805-megahertz bands. In order to cover most of Europe, the ground stations must be spaced every 50 to 700 km (30 to 435 miles).
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…APC system known as the terrestrial flight telephone system (TFTS) in 1992. This system employs digital modulation methods and operates in the 1,670–1,675- and 1,800–1,805-megahertz bands. In order to cover most of Europe, the ground stations must be spaced every 50 to 700 km (30 to 435 miles).
Read More