958
THE HONG KONG GOVERNMENT GAZETTE, DECEMBER 17, 1937.
[Schedule
Every aircraft coming up with another aircraft from any direction IV,-contd.]. more than 110 degrees from ahead of the latter, that is to say, in such a position with reference to the aircraft which it is overtaking that at night it would be unable to see either of that aircraft's side lights, shall be deemed to be an overtaking aircraft, and no sub- sequent alteration of the bearing between the two aircraft shall make the overtaking aircraft a crossing aircraft within the meaning of these rules, or relieve it of the duty of keeping clear of the over- taken aircraft until it is finally past and clear.
As by day the overtaking aircraft cannot always know with certainty whether it is forward or abaft the direction mentioned above from the other aircraft, it should if in doubt, assume that it is an overtaking aircraft and keep out of the way.
30. Every aircraft which is obliged by the rules contained in this Schedule to keep out of the way of another aircraft shall, if the circumstances of the case admit, avoid passing over or under the other or crossing ahead of it.
31. Where by any of the rules contained in this Schedule one of two aircraft is to keep out of the way, the other shall keep its course and speed. When, however, in consequence of thick weather or any other cause, the aircraft having the right of way finds itself so close that collision cannot be avoided by the action of the giving- way aircraft alone, it shall take such action as will best aid to avert collision.
32. Every aircraft in a cloud, fog, mist or other conditions of bad visibility, shall proceed with caution, having careful regard to existing circumstances.
Every aircraft when flying beneath clouds shall always do so, so far as it is safe and practicable, at such a distance below the clouds as will enable it readily to see and be seen.
33. In order to obviate the increased risk of collision which exists on air traffic routes, the following rules shall be observed by flying machines, gliders and airships when flying on or in the vicinity of such routes:
(a) An aircraft when flying by compass along the straight line (rhumb line) joining two points on an air traffic route in common use shall keep such line at least 1,000 yards on its left.
(b) An aircraft following either an officially recognized air traffic route or a route frequented by aircraft and indicated on the ground by a line of landmarks such as a road, railway, river, canal or coast line, etc., shall keep such route at least 300 yards on its left.
(c) An aircraft shall not fly keeping on its right any of the lines or routes referred to in this paragraph except at a distance therefrom sufficient to avoid aircraft following such lines or routes in accord- ance with the rules contained in this paragraph.
(d) An aircraft crossing one of the lines or routes referred to in this paragraph shall cross it at right angles as rapidly as possible.
(e) In the case of prearranged flights in group formation, the aircraft of the leader of the group shall lead the flight in such a manner that every aircraft in the group can comply with the rules contained in this paragraph.
34. To facilitate compliance with the rules for air traffic con- tained in this Schedule, the pilot of a flying machine shall, save in exceptional circumstances, be placed either in the plane of symmetry of the flying machine or on the left hand side of such plane.
SECTION IV.
Special Rules for Air Traffic on and in the Vicinity of all Aerodromes.
35. On and in the vicinity of all aerodromes :—
(a) aircraft about to land on the aerodrome shall be given free way;
(b) aircraft about to take off shall not attempt to do so until there is no risk of collision with another aircraft;