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7.   This system is much more likely to produce accurate fighter positioning
than was the old system of "guestimation", but for its success it depends
entirely on the fighter pilot flying accurately at preselected speeds and
angles of bank. These figures for a Hunter are .9 Mach. and 45 angle of bank.

8.   It is possible, however, that these figures cannot be met. (A Hunter
with 2 x 100 gallon tanks cannot maintain .9 M at 45° angle of bank at 45,000 ft).
Speed should always be maintained under such conditions and the angle of bank
reduced to 30°. The setting up distances then alter as follows:-

     (a)  turn in at 30 n.m. from target

     (b)  displacement 23 n.m. from target's line of flight.

9.   The important point to remember is that as long as the G.C.I. controller
knows at the earliest opportunity what angle of bank is to be used he will have
no problem in re-adjusting the lateral displacement, but he cannot make any
satisfactory adjustments once the turn-in is imminent.

10.   No matter how effective a G.C.I. controller may be in vectoring fighters
onto a target, an early pick up range will always be of advantage. Throughout
a displaced parallel head-on type of interception there is only a one minute
leg available when the fighter pilot is within visual sighting range and has
a steady platform from which to search for the target. Every endeavour should
be made to got a sighting on this straight leg because once the final turn is
commenced the controller is unable to give accurate clock references of the
target until the turn is completed.

11.   Once the final turn is completed pick up will still be difficult - small
area of target aircraft from line astern. Furthermore, by this time fighter and
target "blips" may have merged on the controller's tube and his clock references
will be less accurate. (NOTE: Using the 160 n.m. scale on the Type 80, "paints"
are up to one n.m. long).

12.   In order to at a pick-up at the earliest moment aircraft within a fighter
formation should be flown, to give a maximum of search consistent with
manoeuvrability.

13.   Target aircraft at the same height as fighters will appear above the horizon
because of the curvature of the earth. To place targets near the normal searching
datum, i.e., the horizon, fighters should fly above the target's level,
establishing their height advantage by asking for comparative bights if they
are not being given. 4000 ft. height advantage will put a target at 10 n.m. range
on the horizon, or 2000 feet advantage at 5 n.m. target range.

The Attack.

14.   Once a visual contact has been made, it is important that firing range is
reached as quickly as possible. If there are heavy contrails and a very early
sighting is made it may well be preferable to leave the interception in the hands
of the controller until quite certain of the target's heading. Normally, when out
of trails, the fighter pilot is able to improve on the controller's curve of pursuit
by taking over the interception immediately.

15.   The common fault during the final stage of the interception, is that
insufficient lead is applied and instead of feeding straight round a curve of pursuit
to firing range, the fighter gets sucked to a line astern from which, at an over-
taking sped of .05 m it takes a long time to catch up. (NOTE: .85 Target .9 m fighter
From 2 n.m. to 800 yards = 3 minutes = 25 n.m. of Target Travel).
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