Using Runway 02
Ok, so as we thought, SHG are going to try using Runway 02 with aircraft that can accept the tailwind.
This is fine, except that there is only one instrument approach specified for that runway at present - the RNP one.
It looks as if the VOR/DME approach - in particular the VOR - may not be good enough from the southerly direction, given that the terrain, terminal/combined buildings and also any aircraft on the apron form radio reflectors which could upset the VOR performance. (I assume there is a problem because the VOR/DME approach for runway 20 is blank and totally missing for 02 in the AIP.)
The GBAS system would be ideal for use on 02, but it's not certified yet by ASSI. It's main benefit will be that it will provide good vertical guidance - the only navaid on St Helena to do this. But there may be times when this will be unavailable due to ionospheric effects in the tropical region, when the GBAS correction signals may not be able to keep up with the changes in the radio path.
So far, I think I'm correct in saying that all the flights that have landed on St Helena have been in good VMC. I guess there will be times (perhaps more as the southern winter approaches) where reduced visibility and cloudbase will occur. That will put more pressure on pilots, knowing that they're heading towards a 1000 feet wall of rock (which will hopefully be below and not in front of them when they close in). Not a time to confuse threshold elev and QNH!