This Brochure deals cornprehensively with the Type R.V.A. 492 Continuous Airport Recorder and has been specially prepared for executives responsible for Air Traffic Control and Safety. A copy will be sent to Executives upon request to:
The Managing Direc tor. The Trevor-Johnstone Ltd , 14, Berkeley St., London, W.1.
Telephone: Grosvenor 3871 (5 lines).

Technical Development and Service Departments:
169-174, SLOANE ST, KNIGHTSBRIDGE, LONDON, S.W.1
Telephone: SLOANE 6198-8470.