Sodium approach 1960s

Anybody got information on sodium approach lighting used on raf /rnas air fleet airfields. I know they were group of four either side if runway. There were 3 pairs extending the runway centreline.

I appreciate if anybofy got some information.

I'm a bit confused about the requirements here. Towards the end of WWII most airfields had sodium lamps added to the 'normal' approach funnel of the main runway. Hence these were twelve lights, arranged as three Vees. This was in theory part of Airfield Lighting Mark III.

In addition portable sodium lighting units were available at some airfields to form the Type FF layout, of which there were two versions, day and night. The layout used 26 units, typically ten as approach, the rest as flarepath - the first four pairs at 200-300 yd spacing, then at 400-600 yard intervals. The approach was a single bar 20 feet from and parallel with the threshold. The first pair were 230 yards apart and the next three pairs had just 10 ft spacing between them (the final pair were parallel to the runway to act as orbitting markers.

All very complicated. The night layout had the lamps angled at 45 degrees away from the direction of landing to reduce direct glare.

Post WWII Airfield Lighting Mark VI was proposed which had a very long narrow Vee extending 2,000 yards from the touchdown and employed 68 fittings. There was also a bar of 16 fittings located 400 yards from touchdown. The diagram shows incandescent units type A6 used for this approach - not sodium.

I would have thought that by 1960 the Calvert approach had become standardised which used similar incandescent 'car spotlamp' type units. The problem with sodium lamps was that they couldn't be dimmed.

Another problem with sodiums was the time they took to 'warm up'. You had to switch them on at least 5 min before your aircraft was due otherwise they wouldn't be at full brightness.
I first encountered sodiums at Sumburgh in 1972, There used to be a line of sodiums (about 3 or 4 I think) offset left of the the centreline of runway 33 to 'lead' aircraft in safely as a straight in approach was not possible without it being very steep due to the proximity of Sumburgh head. Watching the BEA Viscounts do a 'Spitfire' type approach following this line of sodiums was 'very interesting'!
At Farnborough, there used to be a concrete tower about 100ft high in the grounds of the Farnborough College of Technology about half a mile from touchdown on runway 25 (now runway 24). This was built to carry an 'MTI marker' to enable us to check the setting up of our AR1 radar, plus it carried 4 sodium lights each angled slightly differently so as to provide visual guidance visible 135 deg either side of the runway centreline when operating on runway 25 at night.