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Decca 424 Airfield Radar

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Decca 424 Airfield Radar

Old 21st Feb 2012, 19:53
  #81 (permalink)  
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Filton had a 424 or similar - I think its gone now. The big (264?) on the hill went in the last couple of years too. A shame - quite a landmark.

The East Midlands 424 is indeed in the Aeropark - and now even the right way up! Google Earth shows it on its side. Looks as if its been given a lick of paint too. Now, on that subject - something that's been bugging me for at least 40 years ...

In the early 70's the EMA 424 head was red. It changed colour to mustardy yellow. Why? Was it a new unit? An overhaul? a change in airfield equipment colour regulations. Or just a spruce up ...

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Old 21st Feb 2012, 20:15
  #82 (permalink)  
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Or simply faded by the blistering sunshine for which the region is renowned?
Saw it used in 'short-pulse' mode one day, similar to an ASMI. You could make out the shape of a BMA Viscount quite clearly.
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Old 23rd Feb 2012, 14:47
  #83 (permalink)  
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Interesting to note how in the sixties the Decca 424 was the "popular" choice for the civilian and military ATC providers. Then came the seventies selection of the 430, AR1, AR1.5 and Marconi 264. Come the eighties it was back to really just two models, i.e. The Watchman and S511. I recall Racal even having a crack at the approach radar market about 25 - 30 years ago, targeting their model at smaller regional airports but I don't believe it caught on. Nowadays I think Raytheon fairly well have the market to themselves. I hope the old bangers and museum pieces have a few years of life left in them yet though.

Still intrigued to know who bought LBA's old 430, and why ?
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Old 23rd Feb 2012, 15:55
  #84 (permalink)  
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I remember the night of the 32 river. I was on TMA NE at EGCC that evening, we did grin a bit.
I also remember a D watch afternoon duty on the Mediator Suites, (i.e. prior to 1993), when, (due to fog), EGNM was the only airport 'open' in northern England.
You accepted everything we offered you. One of the ATSAs asked "where the fcuk are they parking them all?", Yeadon High-Street was the reply. 126.65 became almost a No. 1 Director frequency for Leeds. Brilliant shift!
As I groped my way to the staff car-park at 22.00, there was a P.A. announcement for "Air Malta passengers to board a bus for EGPK" for a 4.5hr journey to their aircraft. Great days!
Are you a fan of 'Steeleye Span' by any chance?
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Old 27th Feb 2012, 09:49
  #85 (permalink)  
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This is what happens when you build an airport on a hilltop marsh. I think, to be fair, nobody could have predicted the golf course river farce but it's the sort of thing that could only happen at LBA !

I've been on duty at LBA a few times when we were practically the only airport open. Not 1993 though, that's before my time. It's quite a bizarre sight to behold, with Flybe, City Airline, VLM and God knows what else parked in every conceivable corner. It doesn't happen very often but it makes for an interesting shift when it does.

As this is a radar thread, may I ask what approach radars you were using at Manchester back in the eighties ? I remember the Marconi (264 ?) close to the (then) 24 threshold and a circular red and white stripey thing closer to the hangars.

As for Steeleye Span, I wouldn't say I was a fan. I remember "All Around My Hat" in 1975 and "Gaudete" a couple of years before. Jimmy Young once played "Padstow" on his Radio 2 programme about twenty years ago. Maddy Prior is, or was, the lead singer. That's about it ! A bizarre question, mind you. Why do you ask ??
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Old 27th Feb 2012, 15:17
  #86 (permalink)  
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The red and white circular thing was an ACR 6 with updated TX RX.
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Old 27th Feb 2012, 17:07
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Thankyou Canard. Can't say I've heard of the ACR6 but I'll try to find out about it. What were the TX/RX mods you mention ? I have come across cases of "standard" ATC equipment packages, be they comms or radar, being tweaked to customer requirements, often by the local tels engineers.
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Old 27th Feb 2012, 17:36
  #88 (permalink)  
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Check your PMs please. Thankyou.
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Old 27th Feb 2012, 17:51
  #89 (permalink)  
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I believe the 1980s Manchester radar mentioned in several posts above was a T4008.

ACR6 scanner with AR1 electronics.
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Old 27th Feb 2012, 19:39
  #90 (permalink)  
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Cossor ACR6 at Bournemouth Airport, 1979 before removal of the aerial to Stansted.

The last Marconi 264 at Filton - now replaced with Marconi S511.

2 s
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Old 28th Feb 2012, 00:17
  #91 (permalink)  
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Mooncrest, Helen, spekesoftly, and canard,
I tried to post this earlier in one go, but it disappeared. So here goes:-.
The History Of Radar At EGCC. - A short trilogy, - in three parts.

In 1970, there were airfield-based 2 radars at Manch, a Cossor ACR6, and a Marconi S264H. Both were sited to the west of the present pier 'C', on the grass area now covered by the north end of the Air Livery hanger and the cargo sheds. The ACR6 was on a squat round concrete structure, (similar to that in the picture above from 2 Sheds), and the S264 was a large yellow/white cosecant-squared antenna.
Manchester also had PAR, and the caravan sites are still discernible on satellite/aerial photographs. The last ATCO with a PAR rating retired 2 years ago, although the facility was withdrawn in the 1970s.
During the 1970s, when PATCRU was in existence, (providing radar cover to support the procedural ATCC at Barton Hall), other radar data was available.
Clee Hill and St. Annes radar data was transmitted to Manchester via 2 parabolic reflector dishes on the tower roof, east of the original VCR. Clee Hill information came via Sutton Common and St Annes via Winter Hill microwave links. At this time the St Annes site was a Marconi 264A, but the original Clee equipment type is unknown to me.

To be continued....................
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Old 28th Feb 2012, 08:43
  #92 (permalink)  
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@ Zooker
Can't add much to the discussion as I only worked the 430 at Liverpool for 11 years (oh, & I had a Cadet Unit Endorsement for PATCRU ) but I was a Steeleye Span fan - I went to school with Tim Hart & his father christened my 3 boys ! Sad to say, Tim died on Xmas Eve in 2009
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Old 29th Feb 2012, 15:36
  #93 (permalink)  
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I haven't flown from Manchester for years. Is the ACR6 still there, lurking behind the hangars ? I can just see the Watchman from the car park roof at Terminal 1. I think it used to be on the south side but had to make way for the second runway. I dare say moving that installation took some doing.
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Old 29th Feb 2012, 22:48
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The History Of Radar at EGCC continues with the integration of Manchester Approach, PATCRU, Lindhome and the procedural ATC sectors at Barton Hall consolidated as Manchester Sub-Centre which opened on 29th january 1975.
The technical side is covered by Derek Henry in an article entitled 'Sub-Centre opening Memories' which is accessible on the NW Region page of the NAT/CAA RSA website.
By the early 1980s, the approach controllers, (SCMA 1 and 2), used the Marconi S264H and Plessey 4011 as their main radars. These were displayed on 2 16'' primary only flouride tubes.
By this time the S264H had been re-located to a site close to the present location of the MCT DVOR, and I believe the ariel was that from the car-park mounted installation from EGLL.
The 4011 was a combination of AR1 electronics, and the Cossor ACR6 head, and was located on a concrete tower just NE of the northern portal of the R/W06 road tunnel. In the mid/late 1980s a modification was carried out to the radar and it became the EN4000, with improved coverage, but stange square blips.
Both these were available for 2nm SRAs, with blips from the 264 almost half-a-mile wide. The 4011 was a great radar, and would give a huge return from a Guppy on a base or if Jodrell Bank was facing north.
Approach also had the use of primary and SSR data from the Clee Hill AR5, and St Annes 264A, on a 'plot-extracted' or, (in the case of St Annes), 'scan-converted' display. This display was used by No.1 director (119.4), for initial identification and sequence planning, No.2, using the primary displays for final vectoring/SRAs.
Approach could operate using the area radars alone, using en-route terrain-clearance criteria.
The area controllers had the use of Clee Hill and St Annes data and could toggle between the two, on horizontal 22" and vertical 16" displays.
Although no Decca 424 was present at EGCC, support was provided to the 424 director at EGGP via the LIV RAD position. This was usually carried out from the TMA West flat top display, using a shared frequency, 119.85, and involved identifying traffic to the 'GP 424 controller, or sequencing if the 424 was affected by clutter. It was a function carried out by both area and approach-rated controllers and dated from the days of NATS having the Liverpool ATC contract. When EGGP became 430 equipped, the task was more of a 'ident' service, as EGGP approach had much improved coverage.
To be concluded............

The Steeleye Span question arose from Mooncrest's ident. It was the label that their first two vinyl albums were released on. A great band, saw them twice at Loughborough students union.
Very saddened to hear about Tim Hart Eric.

Last edited by ZOOKER; 1st Mar 2012 at 09:38.
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Old 2nd Mar 2012, 08:31
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Aha, now I understand the "Steeleye Span " query. My adoption of the "Mooncrest" moniker is from the record label of the same name but specifically from a copy of "Snoopy versus The Red Baron" by The Hotshots which I bought near EGCC.

It appears that many airfields were operating at least two radar heads simultaneously, one for general surveillance and one for SRAs until the early eighties at least. Reading between the lines it seems to have taken some years for Approach units generally to gain an SSR capability, albeit fed in from a remote NATS/CAA site. In fact, this is still the case at EGNM. Beats me why the then airport management didn't buy a complete primary and secondary Watchman package back in '89. How does EGCC provide an Approach Radar service when the Watchman is on maintenance, bearing in mind the primary and secondary heads are co-mounted ?

A question for you Zooker. What is a Mediator suite ? I've heard the word "Mediator" used in ATC circles several times but have never known what it meant. I always guessed it was something to do with the ATC telephone tie-line network but otherwise I haven't a clue.
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Old 2nd Mar 2012, 09:57
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As I understood it, (but I could be wrong), the 'Mediator Suite', - which sounds like a work by Vaughan-Williams, was the name of the furniture in use at Manchester and LATCC.
It usually comprised 2 horizontal radars, with the capability to accommodate 4 sector controllers (2 on each), A Chief Sector Controller (also known as a Crew-Chief or CSC), was in overall charge of the suite, and ATSAs manned the 'wings' or ends of each suite. A 'canopy' provided fittings for the lights, kept the smoke in the vicinity of the ATCOs and tall Chiefs could grab the canopy handles in times of crisis.
Some LATCC suites had positions for military bods too (Pole Hill did, - I think) and the TMA East suite at Manch had the approach controllers sitting next to the SE sector controller.
Each sector had its own suite, Daventry, Clacton, Dover/Lydd etc. If you find one in a museum, you can tell where it came from as the Manchester ones were dark green and the others, from LATCC and CATC were grey.
Sorry to hi-jack the 424 thread, all this should be filed under ATC History really.
Manchester can use Clee Hill and St Annes PRI/SSR data when the EGCC Watchman is U/S, but I believe they have to use 4000' initial altutude to comply with terrain clearance, and 5nm minimum separation instead of 3.
Please feel free to correct any of the above folks if it's wrong. I'll try and finish the EGCC radar thing this weekend.
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Old 2nd Mar 2012, 10:03
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Originally Posted by Mooncrest
What is a Mediator suite ?
A suite of a couple of splittable sectors each with two 22" flat-tops with suspended Flight Progress Boards separated by a Chief Sector Controller's comms panel, two or three long-range verticals and Assistant Sector Controller Flight Progress Boards on the outside (hence the term 'Wing-Men'). Eash ASC was flanked by an Assistant position. Seating in total for 9 ATS staff (1 CSC, 4 SCs, 2 ASCs, 2 ATSAs) not counting U/Ts. Very cosy when fully staffed...halitosis or smoking not welcome. Result: bad backs, twisted necks, colds and flu, twisted ankles from enmeshed chair castors, red and green felt tip on starched white shirts...etc etc... Alzheimer's permits recall of ten suites in all: POL/IRS, DTY/LIC, TMA(N,) CLN E/W, BRS/STU, 20/23, TMA(S), DVR/LYD, SFD/WOR/HUR, plus a Spare Mediator Suite. They are probably all saucepans or exhaust pipes by now.

Another recollection. The original 1970/71 flat-tops weren't, they were domed and the shrimp boats from the shrimp-boat dispensers would sail downhill into the ashtrays. Alphanumeric 4096 code Mode A SSR arrived just in time for Mediator opening night 31 Jan '71...
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Old 2nd Mar 2012, 12:09
  #98 (permalink)  
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Aaah, shrimpboats and chinagraphs, a marriage made in .... but not on a vertical tube when wearing static-inducing, Bri-nylon!!

Now where's those metal strip holders and the Lamson tube gone?

Oops, sorry, must have been dreaming, but, oh what fun we used to have.

On the beach
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Old 2nd Mar 2012, 13:04
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<<Lamson tube gone?>>

Indeed, what fun... When I worked overseas we would pick up a couple of scorpions during the late night lighting check.. and pop them in a Lamson Tube. Normal reaction when one picks up a tube is to unlatch the end bit and shake it on your hand. Yep, worked every time!!!
Old 2nd Mar 2012, 13:49
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Mediator was the civilian part of the ATC system for Area Control in theU.K. (except Scottish FIR) which came into being in the late 1960's early 1970's. The military function was known as Linesman. The full title was unsurprisingly LInesman Mediator. The Linesman part fell out of usage and "the Thing" became known as Mediator, which has now sadly passed on.
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