The VFR mimima (how far you need to be able to see) for helicopters in the UK is 1500m
The relevant parts of the METAR are the 700m vis in FZFG, and BKN001. Not VFR (for a heli in Class D: 1500m/Clear of cloud and surface in sight) by any stretch of the imagination. There's no way he could have flown high enough to clear the crane, and if he was high enough to hit it then he was in cloud, never mind the fog. Either way, he was in solid IMC and shouldn't have been doing what he was trying to do. Coupled with the high workload of diversion in a single-crew aircraft, and probably not having seen the NOTAM for the crane, it's not at all surprising that it ended in tragedy.
Edit: Too hasty. The incident location was within the EGLL Class A CTR and must therefore have been under Special VFR. Under SVFR, there are no met restrictions for helicopters. Still, I have to wonder what made him press on into central London in 700m/BKN001 instead of turning around and bogging off back to Redhill.
The relevant parts of the METAR are the 700m vis in FZFG, and BKN001. Not VFR (for a heli in Class D: 1500m/Clear of cloud and surface in sight) by any stretch of the imagination. There's no way he could have flown high enough to clear the crane, and if he was high enough to hit it then he was in cloud, never mind the fog. Either way, he was in solid IMC and shouldn't have been doing what he was trying to do. Coupled with the high workload of diversion in a single-crew aircraft, and probably not having seen the NOTAM for the crane, it's not at all surprising that it ended in tragedy.
Edit: Too hasty. The incident location was within the EGLL Class A CTR and must therefore have been under Special VFR. Under SVFR, there are no met restrictions for helicopters. Still, I have to wonder what made him press on into central London in 700m/BKN001 instead of turning around and bogging off back to Redhill.