What a great idea. It’s a lovely run from Biggin to Fairoaks. I have enjoyed travelling this leg many times when routing into Fairoaks from Essex. Take a camera and go in an aircraft with good downwards visibility and clean clear Perspex to see and photograph through.
If you come south out of Biggin to the M25 you can turn west to track it as a line feature to simplify navigation. I suggest you keep your height about 1400ft on the QNH and start talking to Farnborough LARS when established on the M25. This height will keep you below Gatwick’s airspace if you stray too far south and this route keeps you out of the way of the gliders at Kenley. But, best of all, it gives some really excellent and unique (only available to GA community) views of the North Downs and its surrounding landscape. The North Downs are an area of outstanding natural beauty and some very interesting geology.
On your right as you follow the M25 you will see the chalk downs almost rear up out of the ground and slope away towards the London skyline. To your left you will be looking across the Weald to the distant South Downs. Both North and South downs are what remains of a giant fold in the surface of the ground. The centre of the fold has been eroded away to produce the landscape of the Weald you can see spreading out to the south of you.
Leave the M25 when just past its junction with the M23. From here the M25 will slowly rise up the Downs and go over them to curve away to the North West. Follow along the North Downs keeping them to your right. The Downs will rise up to a peak at Box Hill then suddenly drop into a wide valley that makes a gap like a giant has cut a huge notch into the hills. This is Mole Gap. This notch is the result of erosion by the River Mole steadily wearing away a path for itself across the Downs. Through this handy gap is where you want go.
Once through the gap the Ockham VOR is a couple of miles away on a disused airfield directly on your route to Fairoaks. Ockham is a great reference point to track into. From here the big yellow hangers on the far edge of Fairoaks will be visible on a clear day. There is an NDB on Fairoaks which can be handy if struggling to visually locate the airfield since the ADF needle will point straight at it.
Farnborough LARS will usually suggest free calling Fairoaks when you get in the vicinity of Ockham. This gives plenty of time to say hello and get joining information and a report on the traffic they have in their local flying area. Keep your eyes out of the cockpit since departures from Fairoaks and other arrivals might also be using Ockham VOR as a reference point.
I don’t think you have any option about crossing Woking at 1400ft. It sits between you and Fairoaks, stretching out along the railway into a restricted area. If you go above 1400 you will interfere with traffic flying into Farnborough. However, thoughtful and gentle engine management can help to minimise your noise footprint. Keep the engine revs at minimum needed for your height and speed and avoid sudden bursts of high power.
If Fairoaks are on 24 with a left hand circuit then I suggest you cross Woking at the Western end of the town to descend and turn to merge into their downwind leg. This gives a long downwind with excellent views of the airfield – I find this very helpful for orientation and familiarisation with airfield layout - and gives plenty of time for the landing checks. The very modern building by the south east corner of the airfield you will see ahead when joining down wind is the famous Mclaren Technology Centre.
Sometimes when coming down on final for 24 I can see family groups on a footpath near the airfields edge. The children, and occasionally the adults as well, like waving hello to the landing aircraft. When you have landed and are sitting in the area outside the cafe you will often see people bring their children there to watch the aircraft.
I have never had any problems with space or manoeuvring a Cessna 172 about the airfield. I expect this relative to what you are used to. I’m used to operating from much smaller airfields so to me Fairoaks looks really big with loads of space.
Great idea I hope you get a sunny day for it and have a fantastic time.