What are the Nav or Comms aerials in this picture?

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Warmtoast- so if that's not a GCA radar set, I wonder how non-visual approaches were made at RAF Changi in the 60's? I don't recall a dual system as you explain the GCA to be. There were certainly regular night landings, with the local Hastings and Shacks flying at night and often the Transport Command Comets and Brits came over night, so I expect some talkdown facility would have existed. There were certainly many days of wet weather with low cloud in the monsoon months.
David T.

[Warmtoast]

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I wonder how non-visual approaches were made at RAF Changi in the 60's? I don't recall a dual system as you explain the GCA to be.

I don't recall what was installed at Changi, but I would consider it most unlikely to be a GCA, which by the early 1960's were being phased out of RAF service to be replaced by PAR's (Precision Approach Radars) at fighter bases. A better bet at Changi would be an ILS (Instrument Landing System). ILS's were installed at RAF Transport Command stations from the late 1950's onwards. The photo below, taken whilst I was at RAF Abingdon in the summer of 1959, shows the newly installed ILS and the fitting party from RAF Henlow, who were supported by a civilian technician from the manufacturers (Standard Telephones and Cables).



For further information have a look at wikipedia's entries for GCA and ILS here:

Ground-controlled approach - Wikipedia, the free encyclopedia

Instrument landing system - Wikipedia, the free encyclopedia

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Really, ILS at an overseas RAF station in the early 60s? I certainly don't recall a ILS array and even RAF Northolt here in the UK, was still doing GCA approaches until a few years ago. Loved to hear that 'warm female voice' saying "Your slightly above the glide slope, correcting nicely, 2 miles from touchdown" etc.
DT

[iceni]

I more than likely worked on three of the five aircraft in this photo. The two Valettas and the Comet.

Excellent photos.

[Hyperborean]

Couple of minor nit picks Warmtoast. Rotating azimuth aerials not necessary on GCA/PAR some had aerials which swept only an arc through the final approach track. I am not old enough to remember the first GCAs but I vaguely recall information regarding the "search element" of GCA, which would of course require 360 degree coverage. Also Decca 424 was not a PAR as it only provided azimuth information so was used for SRAs down to half a mile. Incidentally I understand that the 424 was developed from a marine radar. In its turn it was developed into the 430.

[Hot 'n' High]

Hi 2 sheds, (Post #15) what I meant was that the reason that all Tx aerials and all Rx aerials were separated geographically was to prevent breakthrough from Tx to Rx as confirmed by Warmtoast - even, in some cases, where a Tx is made on one frequency but breaks through on another (the harmonics issue). However, what I was trying to explain was that one of the reasons for the logic in having the Tx group of aerials off-site and Rx group of aerials on-site was, in part, to ensure the DF aerial was somewhere on the airfield (as opposed to in a field amongst some sheep a few miles away). The DF did use a separate array, but, as an Rx system, it needed to be away from the transmitters – hence Tx off-site, Rx on-site! Hope that clarifies my Post #14.

Now, of course, when it came to a Grey Funnel Line landing pad….! Well, you did what you could to minimise the issues but, for several reasons, having a Tx site trailing a couple of miles behind “Mother” was a bit of a non-starter. If nothing else, there was a risk of over-exuberant pilots using it as a “splash target” on their way home or even mistaking it for “Mother” in the heat of the moment! There were other, more practical reasons, but I can just picture the "splash target" - or worse - scenario!!!!!!

[2 sheds]

Hot 'n' High

Thanks for that - probably me being dim.

2 s

[AvroLincoln]

Acr 7d

Many thanks for the reminder of the Decca 424, known in the RAF as the ACR 7D, on which I performed 3rd line servicing throughout most of the 1960s, while I was based at RAF North Luffenham.
For geeks like myself, here is a very thorough article describing this equipment and its use:
decco type | decca type | airfield radar | 1953 | 1232 | Flight Archive

[Hot 'n' High]

2 Sheds

No probs. My vague initial explanation me thinks!

H 'n' H