The markings on a runway are not related it's Cat 2/3 status but are dependant on whether it is a precision runway (ILS) or non-precison/visual runway.
As well as the centreline and threshold markings (piano keys) a precison runway has 2 other types of markings:
1. Fixed distance markings are stripes either side of the centreline at 500 feet intervals from the threshold up to 3000 feet into the runway. The first 2 sets consist of 3 stripes either side of the centreline, the next 2 sets are 2 stripes and the final 2 sets are a single stripe. Some countries, including the UK, do not use the 3/2 stripe convention but instead use thicker pair of single stripes at each point.
2. Aiming point marks are 2 long, broad stripes either side of the centreline approximately (but not necessarily exactly) co-incident with the PAPIs. On some runways these are 1000' from the threshold, but on longer runways can be at 1500'. The aiming point supplants the fixed-distance marker appropriate to that point. The UK uses a checkerboard effect, rather than a broad stripe for the aiming point.
A typical set of standard markings could be: Piano keys, 3-stripe fixed-distance mark at 500', Aiming Point at 1000', then 2 sets of 2-stripes at 1500 and 2000' followed by 2 sets of 1-stripe each at 2500' and 3000'. Continuing down the runway the first set of markings for the other end is should begin with 3000' to go, at about the same point that the centreline lights start to alternate red/white.
Slight variations on these conventions are seen around the world. However, the UK military seem to be unique amongst major nations in not providing it's precision runways with fixed-distance or aiming point markings.
I suspect that the reason the UK military is so different is that some ATC policy seems to be made without paying regard to the international conventions. As an example, major work at a large RAF transport station included fitting equipment with ultimate aim of introducing Cat 2 operations. The new airfield lighting included the standard yellow/green runway lead-off and green runway lead-on lights that are essential to low visibility operations. However, The ATC branch policymakers decided that the green lead-on lights were dangerous as they might induce pilots to line-up without clearance to enter the runway (even though the required stop-bars been fitted). Despite appeals by the operators and the SATCO that these lights were entirely in keeping with international standards and the crews were completely familar with them from worldwide operations, the lights were not connected.
The Flash Earth image of the Oxonian aerodrome shows that Satndard UK civil markings have been painted, but curiously it looks like the aiming point has been put in at 1500' rather than approxiamtely coincident with the PAPIs whch are at 1000'.
Last edited by Brain Potter; 24th Mar 2009 at 19:49.