What are these markings on Kirkwall Airport's runway? From where they are on the runway, they seem like the touchdown markers, is that what they are?
That's the aiming point mark, UK style. The UK AIP GEN 1.7 (2018-8) notes the following reasons for the different marking:
- The shape of the marking means that 1/3rd of it is outside the centre 3rd of the runway and is therefore less prone to rubber contamination.
- The marking is more easily identifiable as it differs from the TDZ markings.
- It provides enhanced visual cues for the angle of approach.
(Source: CAP 637: Visual Aids Handbook, May 2007)
Aiming point. This is where aircraft should touch the runway. Its location depend on landing distance available (LDA). According to Canadian regulation, on common runway length (4000 to 8000 FT) this is located at approximately 1000 FT down from threshold. On longer runways it is located at approximately 1300 FT. As mentioned by “ymb1” this type of marking is used in UK. In North America the aiming point looks like a rectangular shape. For you information, here’s a drawing of Canadian regulation.
During a precision approach (ILS or RNAV (GNSS)), the vertical guidance (usually 3 degree slope) should bring the aircraft close to this point. Even more, the precision approach path indicator (PAPI) if followed as recommended (2 RED / 2 WHITE) should also bring the aircraft close to the aiming point.
$\begingroup$ The picture is of an airport in the UK, not Canada. $\endgroup$ Sep 24, 2018 at 21:50
4$\begingroup$ This isn't an answer to the question. I don't see the markings in the OP in your diagram. $\endgroup$– PJNoesSep 25, 2018 at 19:17
$\begingroup$ @PJNoes - IMHO the post answers/confirms what it is in writing (not visually), then adds additional info about how its location varies with runway length (this variation is in ICAO standards, so a similar variation applies to the UK). $\endgroup$– user14897Oct 2, 2018 at 21:55
$\begingroup$ Aiming point is not where aircraft should touch the runway. It is the point where your eyes would land if you continued on the approach. The wheels, being lower and farther back, would touch significantly earlier on the runway. This, of course, ignores the flare, like all the aiming/glideslope information, but the relation between the aiming point and the flare distance is not defined. $\endgroup$– ZeusOct 3, 2018 at 0:54