From here
Ibra wrote:
To be fair it was, runway 13 & 31 confusion, then landing with tailwind with typical non-radar AFIS in Scottish airports, they have no clue from where you are inbound
Swedish airports don’t use runway numbers 02/20 and 13/31 for this reason. I haven’t seen any other country with this restriction, but clearly there is a point.
What do they do instead? Pretend that they are oriented differently or just avoid those directions?
kwlf wrote:
What do they do instead? Pretend that they are oriented differently
Yes.
In northern part of Norway the magnetic variation is 15 degrees or more. For instance at Berlevåg (ENBV) the geographic direction of the runways are 75 and 255 degrees. The runways are numbered 06 and 24 
Why does anyone have 02/20 when 2/20 can be used?
Normally runway numbers are based on magnetic bearing since that is what is flown. In that case, the true (grid) bearing of the runway isn’t really relevant. But the difference will of course be quite large where the magnetic variation is large.
There are exceptions in the north, due the impact of the Magnetic North Pole. For example, the Magnetic North Pole is located near the centre of the Canadian Northern Domestic Airspace, therefore magnetic compass indications may be erratic. Thus, in this airspace, runway heading is given in true and true track is used to determine cruising altitude for direction of flight in lieu of magnetic track.
Of course that’s really off-topic. The norm for runway numbering is the runway magnetic heading rounded to the nearest decadegree. But there are at least two good reasons this may not be the case. First is the safety reason mentioned to avoid confusion between opposing runways, although there don’t seem to be many countries that apply this logic. The second is the expense of renumbering due to shift in magnetic variation. The larger the airfield, the more expensive. Renumbering the actual runways is the least expense. All the signing and publications need to be modified too which can easily mount into the millions of $$$, especially if parallel runways are impacted. Some CAA’s are more understanding (and lenient) in this respect than others.
Maoraigh wrote:
Why does anyone have 02/20 when 2/20 can be used?
02/20 is ICAO standard. 2/20 is US FAA standard, perhaps for other countries too. This sometimes catches up US pilots who don’t regularly fly internationally, especially when flying to Canada which is ICAO standard and quite close. It may seem strange, but this has indeed caused communications difficulty between pilots and ATC.
I once had my skin saved by sharp witted controllers at Shoreham (02/20) so I approve of the pragmatic Swedish solution.
Pretend that they are oriented differently
Like 02/19 or 03/21?
I think that ESTA (ÄNGELHOLM) is such an example. 14/32 iso 13/31.
