Bought for spare parts…

Just another mid-size two-draw telescope, bought for spares, mainly (I thought) for the eyepiece cap, or the objective lens holder. It looked filthy and old, but had all its lenses, and a nice mahogany barrel: plus the screws looked original, holding the brass to the barrel.

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When it arrived, (as is usual) the eyepiece cap thread was too big to fit the other telescope in the collection that needed a replacement eyepiece cover – the original reason for buying this unit. The objective lens holder was too small to be any use on a 10-sided telescope restoration project, so I had failed yet again. But actually the telescope was quite nice. Only labelled “Achromatic, London”, on the sliding cover to the objective lens, it is not easy to date, it could be anywhere between 1880 and 1930.

DSCN5369It has an old design of objective mounting, and neat brass ends to the barrel. Conventional design inside, with two twin lens cartridges. One slight fault: those neat screws at the end of the second draw are actually (as ever) too long, and scrape on the slider holding the draw, when the latter is unscrewed. So they were filed down internally, to clear the brass holder.

How about a clean-up?

An afternoon polishing with Brasso had some excellent results! The black tarnishing of the draws soon fell away, and the whole telescope was transformed. Even the barrel ends are now shining.

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There were two surprises. First, on the back face of the slider positioned over the objective lens, there is a price written on there, of 14/0, ie 14 shillings, or £0.70 after decimalisation. Presumably it was sold in a second hand shop at some time after its first owner passed it on. That price would maybe have been reasonable in the 1930s.

DSCN5371The second surprise was that the second draw is fitted with a spacer so as to not let the draw out to as long as it could be – obviously the objective lens used was not as long in the focus as had been expected. No matter, at least it had been noticed, and with the spacer it now does not seem to be necessary to push the tubes in too far to gain a focus.

Some before and after pictures in relation to the polishing are shown below.

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Summary

Using the telescope, it is actually very effective, which is the main requirement after all, once you have a clean instrument. Good focus, good view and magnification. Total length open is 18.5”, closed is about 8.5”. Objective is 42mm dia, but the optically used diameter of the lens is more like 1”.

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Acquired February 2017, Accession Number #299.

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JT Coppock 1960s Telescope

So, it is a real change to introduce a telescope from a different manufacturer to this website, particularly one from Leeds….in the provinces even! A centre of industry, yes, but not at all qualifying as a major shipping port – but that did not matter in the C20. It also happens to be where I lived when I first started using a telescope, also in the 1960s.

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This telescope was made by J T Coppock, of Leeds: it is a 3 draw unit, with an additional, short fourth draw which provides variable magnification. Normally referred to as ‘Pancratic’, this works by extending the distance between the two eyepiece cartridges. On this telescope the variable magnification is quoted to range between 10x (closed) through 15x, to 25x (fully extended), and these figures seem like reasonable estimates for the magnification achieved.

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Maximum length of the telescope with everything extended is 21”. Closed up it is 7.25”, and the barrel diameter is 1.625”. All the metalwork, which feels like brass, is grey in colour, as a result of some form of anodising. The barrel is sheathed in brown leather, stitched along the joint. The lens cartridges and the mounts for the draws are all very conventional in design.

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J T Coppock (Leeds) Ltd

I have not been able to find any data on an optical instrument maker named J T Coppock so far. The unit looks as though it dates from after WW2, from the 1950s or 1960s.

In the 1950s and 1960s, James T Coppock (Leeds) ltd was importing Antoria guitars from Japan, and indeed both Hank Marvin and Jeff Beck played one, as did Big Jim Sullivan when he was playing with Marty Wilde. James T. Coppock ceased trading in the early 1980s and Antoria guitar production ceased then, only to be resurrected later.

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Background Data

This telescope was bought on Ebay  in June 2016, from branneysattic – part of the drive to add some more modern examples to the collection. It is Accession Number #279

N&B Petrel 1960: where it all started!

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When I was 13/14, we moved home back to Leeds, and my bedroom, at 53 Cookridge Lane, overlooked Yeadon aerodrome – or at least it was on the top of the next hill. This started me off as an aeroplane spotter, particularly as the approach to the main runway at the time, runway 28, came straight past our house.

I tried using my Dad’s ex-Army binoculars, but could not get on with those, so decided I needed a telescope, to identify any interesting aeroplane (mainly light aircraft) visitors. My favourite photographic shop in Leeds was Beckett’s in “The Headrow”: I think we went there: and without much other choice I bought this N&B “Petrel”, a pancratic x25 – x40 aluminium bodied telescope. I honestly don’t know how much it cost, but when I worked full time at the airport five years later, in the holidays, I earned an enormous wage every week, of £12/10/0: to me that was a fortune, so it could have cost as ‘little’ as that!

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Long range spying

Google maps are now able to tell me that it was 1.75 miles, or 9000 feet, from my bedroom window to the main apron at Yeadon: at x40 trying to use the scope hand-held was impossible, even if the aircraft was parked on this apron. But the small window with hinges at the top could wedge the scope while it was pointing in the right direction: and standing on a little chair I could get my eye up at the other end. Given reasonable climatic conditions, and no heat haze from the airport tarmac, I could just read the registrations on the airliners, like the BKS Dakotas and similar: you could certainly read the airline names. So, if when you come home from school there is something interesting sitting there, the procedure was to jump on a bike and cycle the 5 miles or so to the airport – a lot further than the crows or aeroplanes would have to fly!

Spotting light aircraft ‘on approach’!

The next problem with a narrow angle/field of view of a telescope was finding the aeroplane in the sky – something that had caused a problem with Dad’s binoculars too. But with a telescope and a Meccano set the problem was soon solved. I used my right eye to look thru the telescope, so the left eye was still available and sort of looking in the same direction. The simple instructions are:

Strap a Meccano right angle bracket to a rubber/eraser (the thing you use to remove unwanted pencil marks) using elastic bands, align the Meccano bracket in the same plane as your eyes, and use the left eye to point the telescope so that the aeroplane is in the hole at the end of the Meccano strip – ‘hey presto!’ the aeroplane appears thru the scope view in the right eye. After training your brain/eyes for a while, they work independently, and later, you can throw away the Meccano, as the left eye knows where to put the end of the scope.

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dscn4906The  pictures show the nearest I can reproduce to the original location system these days: I lost the Meccano set when my parents moved house and I was at University – by the way, if you live at 53 Cookridge Lane, you’ll find it by crawling under the floor of the lounge!

The telescope

Nowadays I know that N&B Ltd stands for Newbold and Bulford. The scope is black anodised aluminium – which on occasions got very hot sitting on the bedroom windowsill, with two sections extended and focussed, ready for action. After 60 years the anodising has worn off the main draw: there are three draws in all, one for magnification and the second for the focus, with a knurled finger grip. Closed it is just over 12”, open fully it is 28”: the objective is 1.5” OD. The sliders are all felt covered, to keep them tight. While the knurled ring releases the first draw, the second and third draws have to be removed thru the objective end.

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Many years ago I replaced the plastic type cover on the barrel with some green leather. It was then that I started in a quest to find a decently built brass telescope, to replace this well used unit – but mainly well used at airports and on aeroplanes! You can find all my aeroplane pictures from the 1960s era in the FlickR albums on tinyurl.com/nickplanes.

Accession Number had to be #0 (zero).

Concorde Memorial Galiled (sic) Telescope, 2003

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This is quite an effective, but modern telescope, produced as a corporate gift and specially engraved by some trading house to be a tribute in memory of the Concorde airliner. It is therefore engraved with the Concorde name in the BA logo form, and etched with a Concorde silhouette.

dscn4882Just in case you thought this was a well-engineered British product, that myth is dispelled as soon as you see the title on the box is “Galiled Telescope”, so maybe it was made in space by Martians, or maybe Chinese people, who cannot spell Galileo. Inside it claims to be designed exclusively as part of the British Airways Concorde Collection, to celebrate 27 years of commercial supersonic flight. However it is a very highly polished, chrome-plated brass, with what appear to be two plastic lens cartridges in conventional positions in the first draw. Plus the focal action is a combination of pull out to full length, and then twist to gradually adjust into focus, because the first draw has some sort of preferred spiral/screw thread action (which can be over-ruled by a definite push intended to close the draw.

Description

On the box and on the other side of the objective ring to the Concorde name logo it states the magnification x field as 25x 30mm.

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The scope is a three draw, 5.5” when closed, and 13” when open fully, The objective is a fairly standard doublet: the third draw unscrews from the main barrel conventionally, and the mounting slider is retained by a plastic end cap: it is removed over the eyepiece. The slider itself is a smooth run along the draw, since the mount has a plastic liner. Even the inside surface of the barrel is chrome plated and highly polished.

What I have not managed to do is dismantle the first and second draws to get at the second lens cartridge! Modern stuff is not as straightforward in assembly as Victorian models!

Extending the market

Despite the exclusive design claim, I have also seen variants of this scope offered on Ebay, not just with a Concorde logo and tribute, but also with a version offering a tribute to the Hubble space telescope. This one was new, and cost about £48, in 2005, which was then a fairly standard price.

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The manufacturer’s model number is quoted as LP-888, with the BA Warehouse Code of OP, and Product Code 1402. There has been another offered on Ebay recently labelled as made by Opticron. My Accession Number was #108.

Britex/Orion Spotter from 1950

My first telescope was the one I used for aero-spotting in the early 1960s. It was aluminium, anodised black, made by N&B (Newbold and Bulford, also referred to as “Enbeeco”: this firm eventually disappeared into the Pyser Group). The model was called a “Petrel”: and it lived (extended and focused) on my bedroom window-sill, ready for use on passing aeroplanes, while doing my homework. This was pancratic, ie variable magnification, which worked well, going from 25x to 40x, but needed wedging in my bedroom window to hold it still when using 40x, looking over the two miles distance to the aerodrome on the next hill at Yeadon. Normal aeroplane use was at 25x.

Recently I have been collecting other 1960s/post-war manufactured versions of telescopes, from N&B and from Britex/Ottway – the latter seemed to produce brass built versions, rather than the aluminium ones produced by N&B.

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This “Britex Spotter” looked interesting on Ebay, which overcame the normal reticence that arises when I see any scope, usually a gunsight or other typically military equipment, usually from Ottway, with grub screws. Maybe the knurled bit was a clever focusing ring, it looked OK in the Ebay pictures.

Now researching the name I discover that Britex was actually a trade name of W. Ottway and Co, of Ealing, which maybe explains the design style. The Britex Spotter was produced after WW2 for the wholesale trade market, ie for retailers and multiple resellers I guess, and the range also included names like the ‘Orion Spotter’ and ‘Headquarter & General’. (See the postscript for the Orion Spotter)

The Britex Spotter

The Spotter is a neat two draw short telescope, ie one focusing draw and a pancratic magnification adjustment tube near the eyepiece. It is really solidly built in chromed brass, with the main barrel and sunshade being finished in ‘hammered’ paint. It has a double capped leather strap to protect each end, when not in use, or in transit. With the solidity comes weight, and it is heavy: so I was pleased to have chosen the lighter Enbeeco unit for my own telescope!

The focus on the lowest magnification setting, which says 15x, is only achievable at around 50 yards and longer range, but this becomes closer as the magnification is increased. The 40x magnification is certainly achieved. It is easy to use. Overall length is 21″ extended (53cm), closed it is 11.25″ or 28.5cms. OD is 1.5″.

Nasty bits

I am unlikely to meet the designer who put this concept together, but initially you think he was not a telescope user, and had never worked with a good Victorian telescope design, or even an older design. There are so many extra bits wrapped round the tube, and he did really like his grubscrews. Luckily of the three, two still work, just, but one is messed up: you need to undo these two crucial ones however to access the lenses to clean them. Then you realise that this designer normally worked with the Ottway gunsights used on battleships and tanks – this was their main market – and these would have had to withstand extremes of vibration and shock, so that grubscrews there were probably essential?

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All the bits, except for the grubscrews!

The central cartridge is suspended back from the end of the second draw, on a long extension, but instead of the standard knurled ring we have a silly ring with various cut-outs round the edge, and then, horrors, this also has a grub screw to secure it in place! But to get to this you need to unscrew the ugly external grub screw, which actually holds three separate rings together. First is the “decorative” external machine turned ring: it has no other function, apart from also holding the grubscrew. Second, the ring below, which is on the end of the second draw (and seems to have its own thread and grubscrew onto the actual slider on the draw tube). Third is the machined end of the main barrel, which screws into the middle ring to make the connection between the barrel and the second draw.

Possibly the real reason for the use of so many “bits” to do a simple telescope was that Ottway might have made all the bits anyway for an MoD contract, and had lots of them left over, so maybe they solved a problem and were effectively free-issue, so they used them all anyway and cobbled something together!

History

This scope was acquired on Ebay in November 2016. The previous owner also bought it second hand, back in 1959, so it is certainly a 1950s model, latest. Accession Number #295.

Construction photos:

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The eyepiece and its cartridge

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The central cartridge

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The multi-layer joint

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The objective assembly and sunshade

Postscript: The Orion Spotter

OK, so it does happen, a lot more than it should: I’ve found another very similar telescope in the collection, and this one is engraved as “Orion Spotter” and also says “Made by W Ottway & Co Ltd, Ealing London. Number 52363, British Made”. This is my Accession Number #228. This is identical in construction, and all the major bits, of the Britex Spotter, it is just renamed.

It has the same leather end cups on a strap as the Britex Spotter, and apart from the engraving the only other difference is that the barrel and sunshade are covered in a good quality tan leather, stitched together along the seams.

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Ottway labelled Orion Spotter, with leather cladding

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Ottway’s Orion Spotter

Using a telescope – with Glaucoma

I have no history of glaucoma, none in the family, and was initially, maybe 10 years ago, treated with drops to reduce my eye pressure, picked up in eye tests as being too high. This continued for many years, with more drops, stronger drops, but eventually the field tests showed that I was losing vision in the lower two quadrants of both eyes, initially the left lower quadrant in one, and the right in the other, so I did not lose any overall vision when using both eyes.

I eventually changed hospitals as the specialists in the first were just rubbing their heads, giving more eye drops, and sending me away for another 12 months – they never mentioned Glaucoma: but they lost my notes continually, so started again twice and did not treat the condition seriously. In the second Hospital I was told I had severe open angle Glaucoma, told to advise the DVLA, and take a driving fields test at an opticians – that led to my car driving licence being withdrawn.

The driving field test does not really demonstrate to you how badly your vision is affected. When I can see the effect of the combined blind spots, just under my eye line, it is when talking to someone at normal face to face distance, maybe 2 feet, when if I look into their eyes I can’t see their lips moving: in fact I can’t see their mouth at all. It’s also surprising how a significant part of effective hearing relies on also observing the lip movement.

After 3-4 years at the next Hospital I had moved up the priority list, having been using two different drops to try to reduce the eye pressure – ineffectively. So I reached the end of a waiting list for an operation called a Trabulectomy.

A Trabulectomy

It’s a frightening operation, more from the point of view of your own worries and not for any pain. The eye is immobilised, and anaesthetised, and my surgeon was very skilled. Nevertheless I would have liked some form of tranquiliser into the line they put into a vein in the back of my hand. Maybe I was so paralysed by fear, they thought I was calm. The objective is to put a slit into the eyeball, to allow the internal fluid to drain out through this slit, rather than through the normal route, which has probably furred up. (Maybe we should have bought a better water softener?) From the instrument engineer’s point of view, it’s a drain hole like a safety valve, an over-pressure valve, to let fluid out when the pressure gets too high. Say at over 20mm Mercury, to reduce the normal eye pressure – to the desirable level of 12-15mm Mercury.

The drops used after the operation are of two types: one seems to be an antibiotic, to stop germs getting inside; the other, a corticosteroid, is to ‘stop inflammation and swelling’. This also delays the healing process, so allowing the slit put in the eye to settle down without the edges healing together across the slit, keeping a drain slot open once the eye recovers. So the drop delivery immediately after the operation controls the slot width/gap, and the objective is to make this the right size to suit your condition – – and so it takes some tweaking. Hence the frequent return trips to the specialist to see what is happening.

What happens next?

Now I have one eye operated on, getting better after about three weeks, hopefully the pressure is going to be lower. I am now thinking about the next eye needing the same operation, but next time I’ll ask for something to tranquilise me. It’s a fairly long operation, about half an hour, with them working on the eye and you just lying there, so you can get a bit worried.

After effects are interesting. I’m an optical/telescope/photography guy, with a collection of over 200 telescopes, a few binoculars and other optical things: I’ve always worn glasses and could never bring myself to use contact lenses. I studied physics at University and specialised in wave theory, optics, refraction, etc. So I can see my own blind spots, know that the left eye (yet to be operated on) has a blind spot almost impinging on the centre line, to the right, such that I can check text reading backwards more easily than forwards, etc. Alternatively you can tip your head to the right so the line of text on the PC screen is angled above the line between the eyes.

Apparently the eye has a membrane over the outside surface: when the eye pressure is reduced, maybe this membrane does not shrink, like the outside of the eyeball does. So it is a little loose on the eye. The slot, that somehow in the operation they put in the actual eyeball, leaks fluid out as far as the inside this membrane (which somehow maybe they repair in the operation): it forms in a “bleb”, ie a bubble of fluid, like a lump, on the eye surface, and slowly disperses through the membrane. I think in the operation they inject something to form the basis of the ‘bleb’. Bleb is a real technical term.

After-effects

But when like me you work on a PC, at night, with light radiated directly into your eye mostly, it appears that the folds or ripples in the surface of this membrane can appear to move across the pupil, and at certain angles the light is refracted into the eye, so you see occasional hair like white lines of light running across the field of vision. This presumably will stabilise/disappear as the membrane does shrink, and the eye diameter stops going up and down with pressure variations. I asked the Consultant about this, and he just commented that I was too observant. Trouble is, understanding what I could see, is what made me interested in optics to start with.

Just a final comment: how do you still use a telescope, with almost total blind spots in the lower two quadrants? I use them on aeroplanes, to see the registrations. These you read by almost taking a snapshot of a good sighting into the brain and processing it. The answer I thought was to use binoculars, but it’s not the same. The answer is that you have to use the top half of the eye view, the top two quadrants, for the snapshot, ie aim the telescope below the target of the registration, or whatever. Thank goodness for autofocus on digital cameras!

The future

If the eye pressure is reduced by the dual Trabulectomy, the damage will be arrested, and I will not lose any further vision. But what has been lost, is lost, as it is caused by pressure damage cutting the optic nerve where it leaves the eye: so until they can get little biotic nerve bridging robots to repair that break (and spinal chord breaks in people who have neck injuries), that area of vision will remain cut off. The technique is being developed, with the research on stem cells etc, but not that fast.

Maybe there will be a follow up blog later. But I have to work out whether this is a post that should be used on the “Insider” process control marketing blog, where I always promote the use of optical techniques for process analysis and control, or this Telescope Collector’s blog! The answer is both….

Update December 2016

The Summer was good, plenty of aeroplanes to spot: a bit frustrated I suppose – by lack of trying to use a telescope, in the fear that it would be bad – I called in at a camera shop and asked if they had any image stabilising binoculars. At least that would overcome the standard binocular jitter, but might help the glaucoma.

Came out with the only one in the shop, just traded in, second hand, Canon 10×30. Absolutely brilliant! Maybe not as high powered as my telescopes, but really stable, a lot more time available to snatch a registration when everything else is right. OK, still not converted, but they are the go to pair for fast spotting of overflying aircraft….

Much to my wife’s displeasure I still buy at least two new scopes a month, the older and more dilapidated the better, cos they are cheaper.

AA Radar Telescope from HMS Gloucester

DSCN2346This is a style of telescope that is not normally a collector’s item, because it’s pretty difficult (normally) to do anything with them. This telescope belongs to the categories of: military equipment, heavy and bullet proof, un-damageable, gun-sights and range-finders. But the history of this one is why it’s so interesting.

As described on Ebay it is a Gunsight Elbow Telescope AA Radar L6 A1, which was one of four such telescopes in service on HMS Gloucester, a Royal Navy Type 42 Destroyer. This was offered for sale when HMS Gloucester was decommissioned in Portsmouth in 2011. The wooden box which holds this scope identifies it as 6650-99-965-3364, and on the outside of the lid it is marked as belonging to the “Aft 909”, presumably the location and the ID of the radar antenna.

DSCN2348The telescope itself is painted a grey colour, and labelled as Telescope Elbow AA Radar L4 A1, with the (presumably NATO) number 6650-99-962-6007. It has a 2” / 50mm OD main tube, with an objective aperture of 18-19mm: at the other end of the 12.5” / 32cm barrel, the diameter increases to 60mm where there are mounting slots/grooves to attach it to the radar aerial. The eyepiece is on the side, at 90 degrees to the optical axis, as you might expect from an elbow telescope. Focus is via a knurled knob on the rear end of the main barrel. So far it has not been dismantled.

The view through the telescope is good, although it offers quite a wide field of view, and limited magnification, compared to any other telescope. In the centre of the view there is a square measurement grid, showing two squares of angle off the centre line of view, one marked 10’ and the other 20’. Presumably these markings are minutes of arc, where 60 minutes is one degree – this seems to work out OK in measuring the observed thickness of a lamp-post at a distance. The eyepiece has a soft rubber cover.

DSCN2351Also in the box is a separate push-on lens (Lens L1 A1, 6650-99-965-3365) to cover the objective, in a black housing, labelled “V.I.Y. for targets 25ft to 28ft”. It enables focussing the system on objects closer to the observer.

HMS Gloucester

The Destroyer HMS Gloucester was built by Vosper Thorneycroft in Southampton, and launched in November 1982: after commissioning in 1985 she served in the Royal Navy as D96, alongside the other 13 Type 42 Destroyers of this class. Two of these were lost in the South Atlantic, fighting to regain the Falklands – these were HMS Sheffield and HMS Coventry. After decommissioning, Gloucester was finally towed out of Portsmouth harbour on 22 September 2015, to be taken to a scrapyard in Turkey.

HMS Gloucester being towed to the Turkish scrapyard

HMS Gloucester towed to the Turkish scrapyard

HMS Gloucester achieved distinction in the First Gulf War, in 1991, serving with the Task Force in the Persian Gulf. A previous HMS Gloucester, the Light Cruiser launched in 1937 and eventually sunk in the Mediterranean in 1941, had earned the name “Fighting G”, after ‘heavy service’ in those early years of WW2. The nickname was earned by the later HMS Gloucester primarily from the coalition task force US partners in the Persian Gulf, after the downing of an Iraqi Silkworm missile by a Sea Dart missile.

The entry in Wikipedia gives a useful outline of her full naval career:

(Wikimedia)

(Wikimedia)

Gloucester served in the Gulf War in 1991 under the command of Commander (later Rear Admiral) Philip Wilcocks where her most notable action was the firing of a salvo shot of Sea Dart missiles to shoot an Iraqi Silkworm missile that was threatening the US battleship USS Missouri and allied minehunters; the first successful missile versus missile engagement at sea in combat by any Navy. The ship also survived attacks from two naval mines and conducted numerous boardings using her boarding party consisting of Royal Navy and Royal Marine personnel. The ship’s Lynx helicopter also engaged seven Iraqi warships. She spent the longest period upthreat of any coalition warship. As a result of her endeavours, her captain (Commander Philip Wilcocks) and flight commander (Lt Cdr David Livingstone) were decorated with the Distinguished Service Cross; the operations officer and flight observer were both mentioned in Despatches. After this service Gloucester was rebranded with her nickname of “The Fighting G”.

In August 2010, Gloucester also intercepted and arrested the yacht Tortuga in the Caribbean, which was attempting to smuggle £4million worth of cocaine. This was during HMS Gloucester’s voyage out to the Falkland Islands, where she was deployed from August 2010 to early 2011.

What was the purpose?

www.royalnavy.mod.uk

HMS Gloucester (www.royalnavy.mod.uk)

What is the function of a telescope on a modern (1985 vintage) radar antenna? If you know please tell me!

By the description the radar is an anti-aircraft radar, ie presumably controlling a missile battery to launch the missile with a lock onto the right target being selected for tracking by the radar. Whether the initial radar target acquisition is intended to be confirmed visually by the operator looking through the telescope, (putting the target inside the graticule, if that is the right word) is unknown, maybe someone can tell me, but it seems the most logical duty for an Elbow Telescope on top of an AA Radar.

HMS Edinburgh firing a Sea Dart missile (navynews.co.uk) Today (13-04-2012) HMS Edinburgh conducted the final Sea Dart Missile firing at the North Eastern Scottish range of Benbecula. The Ship fired five missiles, three single missiles and a two missile salvo at an Unmanned Drone target. This is the last time the 30 year old Missile system will be fired as it is due to be replaced by the new Sea Viper system fitted to the new Type 45 Destroyers.

HMS Edinburgh firing a Sea Dart missile (navynews.co.uk)

The Sea Dart missile required a separate radar illumination of the target to lock-on, and be guided to the target: Sea Dart firings where the missile was launched unguided were not successful. HMS Sheffield tried to disrupt their fatal attack by Exocet missiles by launching an unguided Sea Dart. In the action in the Gulf over the SilkWorm missile attack, the USS Jarrett guided missile Frigate launched a close-in defense missile system, in auto-engagement mode, which then (unfortunately) locked onto the defensive chaff already launched by the Missouri, and missed the missile. The Sea Dart salvo launched by HMS Gloucester was already locked onto the Iranian missile, presumably by the pre-launch lock – maybe achieved with the help of one of these four Elbow telescope systems on board.