Redland
Someone suggested 'call PAN' and no-one did so the reason why I am here is to point you in the right direction..... Its a resource that has been ticking over for the last 44 years.
There are three websites where the story of Lippitts Hill [and a chunk of police aviation history] can be found. Some of it is duplication ....
The sites are
Want the latest:- Police Aviation News,
Welcome To Police Aviation News and
Welcome to Bryn Elliott Historian
The first two have Lippitts Hill as a separate story and as part of the history of police aviation [up to the point where Police Aviation News was publishing 'the story' on a monthly basis - 1996]. They are under the 'resources' or "stories & related" tabs on the different sites. The third site includes 01.IL as a chapter on local Waltham Abbey policing in general [1800-2000] under the title Peelers Progress [see Police Stories]. It is all the same words just some of them ae in a slightly different order!
Not many photographs of Lippitts Hill on those sites I may add but I have plenty if there is something specific you are seeking.
Hope this helps.