I have just added this to the map of places to fly your drone at Drone Scene:
Land owner permission not required.
London Borough of Hounslow does not have any laws preventing flight of electrically powered aircraft. This part of the park is large and quiet, and has the large GSK building which is interesting.
The originator declared that this location was not inside a Flight Restriction Zone at the time of being flown on 02/01/2021. It remains the responsibility of any pilot to check for any changes before flying at the same location.
Unfortunately I haven’t found any signs of the flying area however I been there 3 time without problem.
Also I have been on weekdays mornings because the park extremely busy on weekends. (I have a mini SC)
I think the Richmond Park is way much better with a clear sign.
Currently I’m practicing/learning on a tinywhoop so I really don’t need a large space, but my next stop (probably in the near future) will be a 3"-4" so knowing that I can fly nearby is great.
In terms of regulations, do you know if these areas would be considered as an A3 category? (Although not necessary for my next drone as they will be sub 250, it would be nice to know that I could fly something larger without having to travel far)