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enter image description here
Google Earth @ 51°08'52.24" N 0°11'35.71" W

The markings are at 100 m intervals, to one side only of the centerline. They're also lighted as seen below.

They are missing from the ICAO aerodrome chart, and are not mentioned in CAP 637 (Visual Aids Handbook).

I measured from each threshold, but the distances to the first in each set don't match. They also don't seem to be new (judging by older satellite imagery).

enter image description here
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JPhi1618
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1 Answers1

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They are "Rapid Exit Taxiway Indicator Lights" as described in section 9.6 of CAP 637.

9.6 Rapid Exit Taxiway Indicator Lights

9.6.1 Rapid exit taxiway indicator lights (RETILs) provide pilots with distance to go information to the nearest rapid exit taxiway on the runway, to enhance situational awareness in low visibility conditions and enable pilots to apply braking action for more efficient roll-out and runway exit speeds.

9.6.2 RETILs consist of six yellow lights adjacent to the runway centreline and configured in a three/two/one pattern spaced 100 m apart; the single light is 100 m from the start of the turn for the rapid exit taxiway, see Figure 1.6.

Greg Hewgill
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