Viewing page 68 of 349

This transcription has been completed. Contact us with corrections.

if conditions permit, but generally deviations are introduced by unforeseen or inadvertent circumstances, such as changes in weather, enemy activity, change of mission en route or equipment failure. Consequently, facilities must be provided to permit following the optimum pattern and must possess sufficient flexibility to permit necessary deviations.

Essentially, the facilities provide [[underlined]] information [[/underlined]] for use by the pilot to permit him to fly the optimum pattern, to correct inadvertent deviations or to introduce required changes. Certain information must be obtained in flight, either directly from ground control or by the pilot's interpretation of instruments and indications in the aircraft.

The information provided prior to take-off is, of course, essential and may contribute most to the successful completion of the mission. In this report, however, consideration is confined to technical facilities which provide information in flight.

The following items of information relate to the prescribed flight pattern:

(1) Position in space, by specification of geometrical coordinates, such as latitude, longitude and altitude.
(2) Orientation in space, by specification of angular coordinates such as bearing, heading and [[strikethrough]] altitude [[/strikethrought]] [[and here is a handwritten note]] attitude [[/and here is a handwritten note]]. 
(3) Velocity components, e.g., air speed, rate of climb, roll, pitch, and yaw.
(4) Wind velocity (for establishing ground track and speed).

By the use of some or all of these quantities, it is possible to follow a flight pattern and to correct inadvertent deviations by reference to prescribed values. To provide requisite flexibility and to cope with unforeseen difficulties, the following additional information is required.

-3-