Why do airports like Heathrow have a different style of touchdown markers? Also, does anyone know how to add them into FSX via airport design editor? The default Heathrow has these different touchdown markers, how are these added?Here is a picture of them to show what I mean:

The UK aiming point markings are different from ICAO Annex 14 because:

a. 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.

b. The marking is more easily identifiable as it differs from the TDZ markings.

c. It provides enhanced visual cues for the angle of approach.

Many other countries also differ from ICAO

The UK aiming point markings are different from ICAO Annex 14 because:

a. 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.

b. The marking is more easily identifiable as it differs from the TDZ markings.

c. It provides enhanced visual cues for the angle of approach.

Many other countries also differ from ICAO

Quite an interesting question actually (thanks for that!) and a detailed answer.Greece is a country that immediately came to my mind, but there might be a lot more. By the way US airports have all different markings too compared to many European airports, especially regarding touchdown zone/fixed distance markings. Also they make way more use of those yellow chevrons around runway but especially taxiways.Anyways, just as an addition, here's Greek runway markings, in this case they use modified threshold markings, although I don't know the reason for it. They have less stripes (or "piano keys" as some like to call them) and have the runway designator right in the middle of them.This is Corfu:http://hem.passagen.se/lordzed/airport-corfu.jpgAnd from the other side:http://www.aktis-sa.gr/uploads/images/image_1168539098.jpg

This is interesting. To me, the only different ones from the U.S. were in the U.K.. I had never seen the Greek ones before.

Airport Design Editor has an option for runway markings called "Alternate Threshold", which substitutes international markings for threshold, touchdown, fixed distance and precision in place of the US markings. However, I am not sure which countries use the international configuration. It would be nice to have a list, but at least we have Google Earth.

Airport Design Editor has an option for runway markings called "Alternate Threshold", which substitutes international markings for threshold, touchdown, fixed distance and precision in place of the US markings. However, I am not sure which countries use the international configuration. It would be nice to have a list, but at least we have Google Earth.

http://en.wikipedia.org/wiki/Runway#Runway_markingsgives a partial list of countries that use non-ICAO markings.

ADE English manual page 121 had a good rundown of the various marking options available for FSX.scott s..

ADE English manual page 121 had a good rundown of the various marking options available for FSX.scott s..

Thanks, I was able to add these in FSX.