Hyperveloce, regarding SatCom the simplest pattern is a slightly pinched bubble. A dimple in the direction of aim is "way off base" as does a null at zenith. There are steerable null antennas that can do this. There's no utility for such technology with Inmarsat.
And for reference Inmarsat runs in the 5.5GHz to 8GHz region. I believe exact frequencies are on their website (or Wakipoodle.) Up there St Elmo's fire static would have some presence but not very much, I believe. My experience is that the EMI effects of static discharge go down somewhat with frequency above VHF. But I suppose it's a good option for the outage period if there might have been some discharge at that time on the probably track the plane took.
JD-EE