Decca 424 Airfield Radar
 

The previous thread from some years ago is closed so apologies for this...

Is anybody out there still using one of these ? Doubtful, I know, given the vintage technology. I ask because I've recently seen a picture of Leeds Bradford Airport circa 1965 and I can just make out the distinctive shape of a 424 radar head lurking behind a BKS HS748 (it is that old) ! It intrigued me because I thought LBA's first radar was a Plessey ACR430. Obviously not.
We now have a Watchman and that's well over twenty years old itself.

Speaking of the Watchman, is this radar still in use at Manchester (or any other NATS airports for that matter) ? It's difficult to tell from the car park roof if I'm looking at a Watchman or a Raytheon thingummyjig.

Thankyou all :ok: .

Hawarden might have been one of the last UK airfields to use the 424?

Liverpool's 424 was replaced in about 1982 with an ACR430. (Subsequently replaced by an S511 and now ASR10)

"Tilt Up" ;)

I believe some of my ex-colleagues are still using one at Lasham....??

LL Dir, I think that you are correct?

Watchman.
 

Manchester is still using a Watchman but should be replaced in about 12 months time, only NATS site left not sure about anybody else.

Southampton still using a Watchman, and plenty of life left in it

424 still in use at Lasham, the 430 being a development of it using a cosecant squared reflector rather than the original pencil beam which in turn (so I'm told) was originally designed as a marine radar.
Try 'Talkdownman' for more details.

Will Lasham's be affected by the OFCOM frequency band sell off? Something about mods needed to carry on.

SGC

News to me. It's still turning, and still burning...as long as there is a good supply of Ford Anglia fan-belts...

She's off an early fifties frigate. Spares available at the Science Museum apparently...theirs is younger...there's only about three blokes remaining who know how to fix it...there's certainly only three blokes remaining who know how to use it....

The 424 that was used at EMA is on display in the aeropark museum there - visible in google maps satellite view.

Ah, more spares.....

Good to see the old 424 is still hanging on by a thread, but I confess I didn't know Lasham even used radar. But that's another story...

Always to encouraging to know that old(er) ATC equipment is still being used, even in the ATC powerhouse that is the UK. It makes me wonder how much longer our (EGNM) Watchman will be in use before it has to make way for a more modern system. I suppose as long as it does the job and spares are available and economical. The old PO lever key switch panels and Racal headsets gave way some years ago to fancy touchscreens and flimsy Plantronics stuff.

I gather the 424 was something of an acquired taste in terms of usage and maintenance :\.

I still reckon the Heathrow ACRVI was better than all the modern digitised stuff.... but then I'm grossly old-fashioned!

Wonder what happened to that ancient clockwork Echo arrangement at EGMC?

You mean the EKCO ARAA. Spent a lot of time under the curtain talking Carvairs etc . Down to half mile on 24/06 very accurate though care was needed in setting it up after a runway change!!

We had an ARAA at Elstree mid sixties. Never saw it working. Rain came through the necessary hole in the roof...
There was also one at Lasham early seventies. Might have been Sahfend's reject. I understand the trick at Sahfend was to take down the controller's trousers mid-SRA...

The Lasham 'Eckoscope' was the original sarfend one. A guy called Arthur Beaton was the controller there originally (c'74 - 78), however I heard a rumour he wasn't licenced. After him, Des Middleton took on the task and that's when the 424 replaced the ARAA

The first radar installation at Leeds Bradford Airport was an Ecko ARAA. It was replaced by the Decca 424 [originally designed and used as a marine radar] c1963/64.

The 424 [later became Plessey 424] was a splendid piece of engineering but with only a 3cm wavelength worked superbly as a weather radar not quite as superb for seeing aircraft during heavy weather! The 424 with its various devices for removing weather clutter and a tilting aerial [the ATCO needed two pairs of hands at times!] had a maximum range of 25 miles and also had a one mile range setting enabling it to see airfield movement activities although, of course, not approved for that purpose.

The Plessey 430 arrived at Leeds Bradford early to mid 70s. This provided better vertical coverage [as opposed to the single narrow beam of tthe 424] but again being 3cm wavelength was often badly affected by weather clutter. Later modifications to the 430 made significant improvement but not until the arrival of the Plessey Watchman was the weather clutter problem resolved for LBA.

With the LBA standard weather [cloudbase below the top of Murgatroyd's chimney, itself later replaced by a fish and chip restaurant!], SRAs to half a mile were the most important approach aid. SRAs were 'the norm' to Rwy 15/33 and 10/28. Of course the advent of the Watchman meant that LBA no longer had the half mile talkdown capability but did, by that time, have an ILS on both ends of the main runway. SRAs to half a mile had continued to be available on Rwy 28 until the Watchman arrived.

Those were the days!

H49

The Watchman installed at Farnborough was MOD owned hence it had permanent touchdown markers in the form of MTI markers ie battery driven devices which 'broke through' the MTI, so we could (if approved) have done 1/2 mile SRA's, but we also had a CR62 (3cm precision approach radar) so this wasn't necessary as you could do 1/2 mile 'no glidepath' talkdowns on the CR62 instead.

Still is, still does, still do, still has, still isn't. And all with classic tangential fade...
If it hadn't been for John Townsend I would never have understood such a radar...

You're all talking nonsense.....Marconi 264 for me (so good, we had 2 of them at EGPF)

I remember doing SRAs on a 264 - targets as big as half-crowns!

HD, you were paid half-a-crown per SRA then...

We are ATCOs...

We had three at Heathrow, so ner. The East, the West and the 'T'...er...didn't we...?

I'll have another glass of Alzheimer's, please, just a little more tonic this time...

Helen,

I've not heard of the Ecko ARAA before and I can't find any info on the web. Was it a widely used machine ?

Yer shoulda seen the blip size on the 232; bigger than the 264 and it wasn't approved for SRA's!
Now the T82 at Lindholme had superb blip size.....................

As did the type 80 at Sopley, but when that went off for mx the 264 blip was wider than the Airway at range!
Nearly as good as the noddy height finders which gave you a height +/- 5,000ft.

Part of the famil for the T80 was to go into the cabin that went round with the head, without turning it off, to be shown "stuff" - can't imaging H&S allowing that nowadays.
"Just mind your step as you get out"

Still got mine, somewhere in the attic.

http://www.vectis.co.uk/AuctionImages/94/1160_l.jpg

It's Ekco....E. K. Cole.

Here's a link about the ARAA with a video showing its use, and some stuff about E. K. Cole

Reckon the Gailes Types 7 & 14 took the prize for blip size - could have featured in WW2 movies, no problem ! :)

Type 82. Now there is a quality radar. Anyone for ACR7? OOSA.

Lon

I have just uncovered those very items in the late Mr C's collection - along with a great deal of other 'stuff'
Lotsa Dinky things in there too.

Didn't E K Cole run a Percival Prentice?

SGC

They operated two Ansons firstly G-ALIH and later G-AGPG. They were used for radar calibration and had a radar fitted in the nose. The pilot was a dour Scotsman John Meredith.

Er Octavian; isn't 'ACR7' the RAF way of spelling of '424'?

Both are in the film...

.....wonderful!

Come on NATS, get a proper dress code for your staff: Double-breasted suit, tie, pencil moustache, National Health glasses, briar pipe and a bucket-load of Brylcreem. Controllers were MEN in those days! (Well, apart from the girl with the mike on steroids).

Just love all the civil titles: "Pilot Meredith", "Chief Controller Cusworth".
Just imagine: "Assistant Sector Controller Smith please be so kind as to coordinate Viking George Able How Oboe Uncle with Birdlip sub-centre at Flight Level Four Zero"..." Certainly Crew Chief Cholmondly-Warner, I shall delegate the task to Woman-Sector Assistant Daphne whilst Cleaner Doris empties my ashtray and I sharpen my HMSO pencil"

Ah the 424, those were the days, 22 years old, all the hosties that I could handle (or could handle me), 52 1/2 mile SRAs in a 13 hour "day radar" duty, trying to keep the thing in tune to avoid loosing radar contact, variable polarisation to try and beat the weather, not forgetting the aerial tilt, and down the pub for a quick lunch, who ever invented SRATCOH and spoilt it all?

424 Airfield Radar
 

I was responsible for installing the LBA ACR430, which replaced the 424.
The 424 was sold to Brough, purchase negotiated between the then LBA Airport Commandant, Geoffrey Sellers and Derek Whithead of Brough. Derek used to fly across in a non-radio Blackburn B2 tail-dragger. After landing on the runway, he would get out, put his arm round the tail and walk across to the apron pulling the aircraft ! Derek was a great character, who had undertaken a vast amount of military fast jet test flying. He later joined CAA as an Aerodrome Inspector based at the then CAA HQ at Kingsway London.

When the ACR 430 was purchased, I was checked out by Plessey and then rated by CAA. I was then responsible for checking out the remaining ATCOs before the CAA Inspector came across to do their ratings.

Although the ACR 430 had several technical advantages over the 424, the latter produced a much sharper return and the narrow beam width enabled proficient operators to ( roughly ) monitor aircraft height. The 424 was much preferred for superior precision during radar talk-downs. There was, of course, no ILS at LBA at the time.

The 424 was not the first aerodrame radar at LBA. It was preceded by one that I cannot unfortunately remember the name of. It was a very imprecise piece of equipment, but was used for talk-downs. In those days, Air Traffic Control was located in a sort of diy glasshouse on top of the old ex-RAF Officers Mess. The radar was mounted on the roof with a sort of periscope suspended from the ceiling in the centre of the visual control room. Luckily, I did not need to validate on the equipment as it was withdrawn by CAA.