Thanks Lear 23 and spoilers yellow, very helpful - as I suspected it is a little complictated. I am surprised, however, that Jersey has not taken the decision to upgrade their ILS category. I presume this would be very expensive but as you say Lear 23 there must be a huge impact on the island and especially the airlines whenever this happens.
Airline was British European - however not sure of the type as it was not me who was flying in this case.
Could you also explain exactly what features are necessary to make an aircraft Cat 2/3 capable, and what avionics exactly are required to make the ILS installation the same - ie what are the differences between a Cat 1 ILS and a Cat 2/3?
Even if Jersey did install a Cat 3 ILS, would there still be a problem in using it below a certain vis because of the short runway length?