Hi,
you can get some pretty interesting tailwinds when on the ILS to runway 30.
Here is some data from ISB airfield.
Elevation approx 1700ft.
Approx bearing of 320 degrees and 12nm from the airfield is a peak of approx 3900ft.
Landing dist on Rwy 12 is 3017m. Landing dist on Rwy 30 is 2743m. PAPI on both runways. Very basic approach lights avail on Rwy 12 (H-S).
Second half of runway 30 is downhill.
For a Cat c aircraft the circle to land is 850ft agl and with a vis requirement of 2.4km (not sure if aircraft is cat C or D).
Dont fly over the city to the south or through prohibited area 254 which is south also.
We have a note in our manual regarding possible GPS outage due jamming in ISB.
Heavy rain can cause mud on the runways and the obvious dangers of rubber deposits.
Its seems the wind favoured the circle to land in marginal conditions.
Rgds.