http://www.caa.co.uk/docs/33/ga_srgw...osterJan09.pdf
Note guidance offered:
Watch for existing circuit traffic and adjust your path to sequence safely.
Rule 12:
Flight in the vicinity of an aerodrome
12.—(1) Subject to paragraph (2), a flying machine, glider or airship flying in the vicinity of what the commander of the aircraft knows, or ought reasonably to know, to be an aerodrome shall—
(a)
conform to the pattern of traffic formed by other aircraft intending to land at that aerodrome or keep clear of the airspace in which the pattern is formed; and
(b) make all turns to the left unless ground signals otherwise indicate.
(2) Paragraph (1) shall not apply if the air traffic control unit at that aerodrome otherwise authorises.
Rule 9:
Converging
9.—(1) Subject to paragraphs (2) and (3) and to rules 10 and 11, aircraft in the air shall give way to other, converging aircraft as follows—
(a) flying machines shall give way to airships, gliders and balloons;
(b) airships shall give way to gliders and balloons;
(c) gliders shall give way to balloons.
(2) Mechanically driven aircraft shall give way to aircraft which are towing other aircraft or objects.
(3) Subject to paragraphs (1) and (2),
when two aircraft are converging in the air at approximately the same altitude, the aircraft which has the other on its right shall give way.
http://www.caa.co.uk/docs/33/ga_srg_09webSSL06.pdf
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