Presumably good for melting snow and ice, but of little or no benefit to fog dispersal?

During the latter part of WW2, it was a massive glider pilot training school too.
As I said, there was definitely FIDO at Blackbushe, last lit in the '50s I think with some of the open channels for the burners still existing.

At risk of a bit of thread drift, but hopefully the Mods will be tolerant, there is an excellent book about FIDO: Flying Through Fire, by Geoffrey Williams, from which I have cribbed this list of UK FIDO equipped airfields:

Blackbushe
Bradwell Bay
Carnaby
Downham Market
Fiskerton
Foulsham
Graveley
Ludford Magna
Manston
Melbourne
Metheringham
St Eval
Sturgate
Tuddenham
Woodbridge

Hope this is of interest.

In fact I've discovered a Pathe News clip dated 1952 showing it being tested.
www.blackbusheairport.proboards.com in the section entitled 'Any movie clips Blackbushe related welcome'

Some testing was done in I think Queen Mary reservoir west of what is now Heathrow. In the early part of WW2 dad was in the AFS/NFS and was on fire cover for the tests

chevvron's link is broken - try this

Fog.. | Blackbushe Airport - The one-stop Forum

Well it was 3.30am!
I've corrected it now.

The 26 Cat 1 ILS was quite good enough for a Tristar autoland, if done correctly. It wasn't cleared of course. What was really dangerous, in my opinion, was the requirement to disengage the autopilots at 200ft/DH. On disengagement, the autopilot inserted a safety pitch up. Just what you need when all you have for visual reference is 2 bars of lighting!

More FIDO digression:

Marham was a FIDO station. Trials of FIDO Mk2 (burning kerosene) were being conducted as late as 1959 - presumably for the V Bombers, which also had the very first operational auto-land system in the Leader Cable. The fuel farm that used to be just North of the 24 Threshold was the original tank system for FIDO and was sometimes referred to as "The FIDO Farm".