Popsy and Orange Nell

Petrus

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I am currently seeking any information on two types of missiles that were conceived in 1950s by the Royal Navy as anti-aircraf guided weapons for ship of frigate size: the Popsy and the Orange Nell.

As for the Popsy there is a webpage containg some info on that at http://www.skomer.u-net.com/projects/popsy.htm:
Popsy was a SAGW to meet the Admiralty's 1948 requirement GD 81/48 to protect small ships from threats similar to the wartime German Fritz X, Hs.293 and Hs.294 guided bombs. There was also a requirement to deal with future weapons such as Blue Boar. Two solutions were examined a small SAGW and an anti-aircraft gun called DACR. This was a rapid firing cannon to be mounted on a "Scarecrow" mount. No further details of DACR are available.

The initial proposal for Popsy was a small subsonic boost/coast missile with wrap-around boosts on the 8.5" (21.6cm) diameter fuselage. Popsy A was 4'8" (1.48m) long, about 5ft (1.52m) long in total with wrap-around boosts. This later changed to a 7"(17.8) diameter tandem boost giving a total length of 8ft (2.44m). Maximum speed was 900fps (M0.8), which was thought to be adequate to defend the frigate that had launched it. Guidance was to be either command link, or later semi-active homing using Continuous Wave Q-band guidance with the Type 992 radar and a CW illuminator.

However, since these frigates would no doubt be escorting convoys and were too small to carry Sea Slug, it was decided that Popsy should have a capability to intercept aircraft (with speeds less than Mach 1) and also be capable of being launched from merchant vessels.

Popsy B was slimmer with a diameter of 7.5" (19cm), longer at 6'8" (2.03m) with a 5ft 10" (1.78m) tandem boost. The bigger boost raised launch velocity to 2200fps (M2.02), with intercept velocity being 1500fps(M1.38).

Popsy B appears to have shared a common airframe and semi-active homing with Red Hawk. Red Hawk was "de-spec'd" to produce the Blue Sky AAM that entered limited service as Fireflash. It is also possible that the Homing Test Vehicle, HTV, later called CTV.4 was a prototype for Popsy B.

The next variant was Popsy-Meteor, which used a sustainer from the US Meteor AAM giving twice the range at 12000yds (10.9Km). It was also considered that the Meteor AAM with the Popsy homing head would make a very good SAM. Mopsy was born.

Mopsy was a 1950 joint US / UK project to GD 165/50 whereby a Meteor without the sustainer was fitted with the Popsy seeker. Mopsy was to be used against supersonic aircraft and missiles. The US Navy wanted Mopsy to be fitted to merchant vessels, with guidance to be carried out by a "mastership".

Popsy and Mopsy did not proceed, possibly as a result of the Admiralty watching the problems developing in the Sea Slug programme.

popsy.jpg


Does anybody know more on this project? I would be especially grateful for any info on how it launcher would have looked.

As for the Orange Nell there is even less information available on the Internet. http://www.skomer.u-net.com/projects/start.htm says only that this was a "SAM smaller than Seaslug that could be fitted to small warships such as frigates", and that the project was cancelled in 1957.

Any input would be welcome.

Best regards,
Piotr
 
I seriously consider buying the book... and others from the "Secret Projects" series...
Hmm... I have recently watched "The Fiedler on the Roof" on TV... and "If I were a rich man..." still sounds in my ears ::)...

Piotr
 
From British Secret Projects, Hypersonics, Ramjets and Missiles

'Orange Nell - the twin-rail launcher would replace a 5" gun turret and would include a magazine with forty missiles stacked vertically in two concentric rings'

Range 1.1miles to 5.7 miles

Size approx 8-9ft long, body diameter about 1ft or 2ft across the four wrap around boosters (based on the scale with the diagram in BSP).


Were the wrap around boosters already fitted or like Sea Slug fitted prior to launch?

Given Popsey had tandem boost, why the change to wrap around boosters?
 
Given Popsey had tandem boost, why the change to wrap around boosters?

I thought there was a mention in BSP4 - something about uncertainty as to the stability of tandem boost?

RP1
 
So rather than needlessly add another thread I'll just do a bit of necromancy...

Reading my Friedman I find him stating that Orange Nell was 6ft long with a 4ft booster, both solid fuel and weighing a total of 500lbs.

This seems to contradict BSP.4 where it states the weapon had wrap around boosters.

So who is correct here?
 
Both Probably, but I have a drawing showing a 'typical' missile and a report that says wrap-around is the preferred configuration

Chris
 

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Both Probably, but I have a drawing showing a 'typical' missile and a report that says wrap-around is the preferred configuration

Chris
Thank you for the reply and pictures!

So it might be possible there was a tandem boost design somewhere that Friedman came across.

On the other hand he's stating that ON developed from Mopsy which was based on the US Meteor AAM.
So it's possible he's either confused things or seen an early diagram that carried on the earlier tandem boost.
 
A thought.
Deck heights were standardised at 8ft, which means any missile over 7.5ft is frankly too long for vertical storage. Once you need two deck heights you might as well get a 15ft long missile.

Further thought.
Vertical storage means the greater the cross sectional area taken up the less missiles per square foot of floor you can fit.

So wrap around boosters are a less than ideal solution.
 
I suspect that the wrap around solution was favoured simply because the only British practical experience at that point was such a layout (Bloodhound/ Thunderbird etc.).
Had this progressed to the next stage and companies actually started to look at possible hardware then peacefully they would have explored a tandem boost layout, after all this system would likely not have entered service until the mid-1960s.

Like with NIGS, I think its tempting to read too much into what really was a low-level study that didn't get much beyond generic calculations unfortunately.
 
I'll go further and suggest that they'd look at a Tartar-like dual thrust motor on a unitary missile. As boosted phase of flight is potentially problematic for guidance and tends to increase minimum range.
 
More thoughts....

Got to be a monopulse seeker.

A desire for local area defence is strong. So size and weight may not decrease, rather performance increase.

Considering the times, Elliots efforts on MRS.5 computer is relevant. A 5ton system making it larger and heavier than Sea Wolf. But to be expected for the period.
 
This programme did continue and it ended up being Sea Dart, on the way unitary missiles with Tandem boost were looked at - there are diagrams of such missiles, in hypothetical form, at Kew along with comparisons to Tartar. The original SIGS/CF.299 staff requirement from late 1960 was a re-write of the 1956 G.D.45. There was continuity of thought going all the way back to 1948, the desire to replace the 3 inch Mk.6 or 4.5 inch Mk.6 and MRS.3 combination with a guided weapon, even though the concept evolved. A 1959 report declared the requirement possible but pointed out that no in-service radars met the requirement. ASRE/ASWE had been busy with the large FSR for NIGS so had not been looking at Small Ship solutions, when a staff target for such a radar was approved, D.N.110(T), ASWE made some tentative proposals but they don't appear to have got very far before Type 988 came along.

Type 988/Broomstick was attractive because it would be available soon, in theory, and allowed a cost sharing package deal with the Netherlands. Any European country would have done and discussions about naval radar were held with the French too. However, it seems that significant factions of the RN didn't like the Type 988 from the outset, it lacked the tracking functions the RN wanted, was not as advanced as the work ASWE were doing, they felt its data handling and power requirements were too great and its size and weight meant it could not fulfil the requirement for SIGS to go on a 3,000 ton ship. They didn't like the use of S-band either. The British side went so far as to set up a joint 2 man study group with the Dutch to see if the Type 988 could be designed in such a way as to allow the British to replace the Dutch aerial with an ASWE designed version as an M-modification at a later date - given the planned timeline it could not. I described the impact this had on the Sea Dart system here.
 
It turns out that a huge amount of the ASWE thinking around SIGS (guidance, surveillance, illumination etc.) survives. It seems that the need to fit the system in a 3,000 ton ship was the primary driver and that the required space, weight and power characteristics from the surveillance radar to achieve this came from DGS, as such the basic requirements were:

Maximum aerial weight of 3 tons
Diameter of swept volume of 12 ft
Aerial to be mounted 70 ft above the waterline
Power consumption, from the ships mains system and including data-handling, of under 80 kw.

ASWE proposed a single rotating aerial that featured a small electronic scan in azimuth as well as electronic scanning in the vertical plane, it would have operated in C-band. The aerial was was 8 ft 6" wide and 8 ft 6" high and consisted of a stack of linear arrays fed by phase shifters, it would have rotated at 40rpm. There would have been 3 transmitters at 2.5 mw peak power each. There was technology, though not components and it is a different configuration, from the NSR for NIGS in this concept. The staff requirement called for a 50% probability of 'painting' a 1 sq.m. target at 200nm. ASWE thought they could get close to this (180nm) with their basic proposal but to reliably meet it they would either have to successfully develop a maser receiver or step up the aerial size and radiated power with a corresponding impact on ship size.

The Dutch radar offered marginally superior performance but at twice the space and weight allowance, at the time it's aerial was to be 16ft 6". ASWE considered their own S-band radar scaled to the size, weight and power of the Dutch set and thought it would result in superior performance to the latter but there was no way that either would fit on a 3,000 ton ship (it would have had a 12 ton aerial weight). The selection of the Type 988 over the smaller ASWE proposal was probably one of the first big drivers in the size growth of the Type 82.

As a result of the above I have had a rethink of these drawings. In the report they are from they are used to illustrate arrangements for missile handling systems for a combined stand-off ASW and CF.299 fit in a 3,000 ton ship, I had assumed the depicted ship to be generic but had always wondered about the surveillance radar and the presence of illuminators. At first glance its dimensions and location appear to match those outlined above, being mounted as high as possible and about 12 ft wide. Additionally, as Ikara equipped ships would not have MATCH, CF.299 was conceived as a 4.5" Mk.6/MRS.3 replacement and these ships were originally seen as direct follow-ons to the Leander class the lack of a main gun may be an intended armament fit rather than the product of a simplified drawing. Therefore, those drawings, especially the ones with the Ikara and CF.299 specific launchers, may be much closer to what the RN then (1961/62) had in mind than I had previously understood, e.g. they are a planned 3,000 ton hull/propulsion combination with outline SIGS and Ikara systems meeting the size, weight and power requirements as they existed at the time.

With regard to the growth in the size of the T82, I don't believe for a second that a 40 Sea Dart, 20 Ikara armament fit with the above mentioned surveillance radar could have been achieved on 3,000 tons. The Type 42 proves that, 3,500 tons for a planned 26 missile Sea Dart outfit and MATCH with Lynx, and it was still too small. But there are clear drivers in the T82's size, the Type 988 seems the most significant (when CVA01 was cancelled it had a 9 ton aerial weight with an additional 3 tons for the radome), the added weight and complexity associated with the RN Ikara launcher another, once the switch was made to a propulsion plant based on that of the County class all bets were off. With the ASWE C-band surveillance radar proposal, 40 Sea Darts with two illuminators and a 20 x Ikara outfit (especially with an installation closer to the Australian one) without a main gun seems viable on 4-5,000 tons.
 
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3 transmitters is likely 3 linear emitter arrays, with each scanning a segment of the total.
Seems unlikely it would be 3 arrays.

I'm intrigued here, as this really looks like the system they should have been working on instead of the NSR for the next generation 3D radar to succeed Type 984.
 
I would like to agree with your analysis that the surveillance radar on those escort frigates is the 8ft 6in AWSE radar, but sadly its not. Those generic escort studies come from the early 1962 project study into Ikara, Asroc and Malafon. The working group report was dated May 1962 and in the description of the frigate design it states "A Netherlands surveillance radar is shown on the foremast." I have attached the relevant page of the report.

I will admit that the shape of that randome strongly reminds me of another that was shown on the early CVA-01 study, specifically the SCC Project 35 sketch design dated March 1963 (as shown in the Warship 2014 article by Ian Sturton). By my scaling that randome would be about 16ft in diameter at the base, sitting as it does on top of the foremast/mack. Height is about 22-23ft. So bigger than needed for the AWSE radar but smaller than the later Type 988 randome.

I think its clear that the early Dutch 'Broomstick' studies when the programme began in 1960 were probably much closer in size and capability to the AWSE radar. It may explain why the decision was made quite early on to go with the 'Broomstick".

The ASWE is a curious body, a lot of research was clearly done during the 1960s but few of those novel concepts seemed to make it to the ships. For example in 1963 they were working on a 'Within-Pulse Electronic Scanning' radar with a 360 degree cylindrical array (at that time limited to X-band) and in 1968 a C-band frequency-scanned planar array (which made it to prototype form).
 

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Surely this C-band planner array is the outcome of ASWE efforts into a 3D set originally for SIGS? Just as JCF Fuller has described?
Considering the rate of progress on these things 1968 is not that surprising.
8n fact doesn't that tie in with the progress on the Type 82?


However the cylindrical system is intriguing....
Didn't the Soviets develop something like that?
 
Thanks Hood, I have previously seen that file but had forgotten the reference to the Netherlands surveillance radar. However, I still don't think they are that generic, definitely not final designs but given what we know about the proposed propulsion plant, staff requirement and displacement at the time they are probably much more indicative than I had previously thought to what was then being considered. That is, all the outline pieces are there including hull and propulsion space as well as armament.

ASRE/ASWE seems to have followed a demand signal from the wider RN leadership. In 1956/57 they were looking at a small ship Air Warning and Interception Radar at about the same time as one of the flurries of activity around a small ship guided weapon (G.D.45 referenced above), this seems to have become the Type 965 even though the missile system was paused. Then focus switched to NIGS and so did ASWE's, when this programme stalled their emphasis shifted to the small ship requirement. When the decision was taken to adopt the Dutch set ASWE were left supporting a design conceived by the Dutch that they felt was a poor concept. If anything I detect frustration from ASWE that they had carefully crafted their C-band proposal to meet the ship-fitting requirements laid down by DGS only for a Dutch set, that greatly exceeded those requirements, to be adopted instead. ASWE went as far as to produce an S-Band proposal using their technology (and the transmitter proposed for the NSR) scaled to the size, weight and power requirements of the Dutch set (16 ft 6" aerial weighing 12 tons) to demonstrate that freed from the previous ship fitting constraints they could greatly exceed the performance of both the Dutch set and that asked for in the staff requirement.

The surviving documents, notably an aide memoire included in a later Broomstick file, strongly imply that the adoption of the Broomstick was a decision taken at very senior level (Board members and Naval Staff). The ASWE files are explicit that the Dutch radar was a very different animal, in terms of size, weight and power requirements, to the ASWE proposal from the very beginning. The intriguing thing is ASWE seem to have been ahead of the curve in understanding the impact Broomstick would have on ship design compared to the ship designers themselves, at least based on the narrative in Friedman. My theory is that the perceived need for collaboration with a European ally resulted in the adoption of the Dutch radar without sufficient consideration of its likely impact on ship size, a decision that in turn meant the Type 82 could never be the next generation First Rate A/S frigate (FSA) it was originally programmed to be.

The collection of files from the late 1960s (1967-9) looking at phase scanning radars is curious, I can find no evidence of a causal link but it is fun to speculate that ASWE resource may have been freed up by the UK withdrawal from Broomstick and someone was thinking of a new UK radar to fill the void it left. Thus ASWE picked up its electronic scanning radar work again. The scale of the prototypes suggests a serious effort.
 
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@jcf Fuller
So does this relate to the statement about a C-band radar of 300nm range?
As increasing antenna size from
8.5ft to 16.5ft is no small increase.
 
There was an article on Anglo-Dutch co-operation in Warship 2019, snippets of it can be read on Google books.
The section on Broomstick seems to more or less tally with what we have discussed here, but claims that ASWE's project was aimed at 6,000 ton ships, but then goes on to say the Type 988 was criticised on size and weight. I wonder if the author perhaps confused the NSR work with the smaller radar? The author also claims the ASWE set was considered for retrofitting in a later refit, which would indicate the Admiralty did not think the radar would be ready until early 1970s.

I would agree that the kickstarting of research after we left Broomstick was not coincidental. Its just a shame no work had been done in the meantime to have something in the wings to avoid Bristol ending up with the 965 and 992Q combo of the Counties.
 
I suspect that section in Warship 2019 was taken from the aide memoire I mentioned previously, many of the words match. The aide memoire gives a fragmented early history of British involvement in the Broomstick radar. It starts by outlining that ASWE had been working on a static aerial away in which Frequency and Phase scanning in Elevation and Azimuth respectively would be used. It would be suitable for NIGS and intended for 6,000 ton ships (its referencing the the NSR). It then goes onto state that when staff priorities shifted to the small ship programme ASWE "evolved a first attempt at a suitable design" to meet the requirement to fit a 3,000 ton ship - this does not match with the ASWE documents which show at least two designs had been considered in depth and the final proposal was a refined version of the second. Given the reference to an SSSR in the NIGS documents they probably spent a lot of time coming up with the concept. ASWE presented cost estimates and development schedules for their proposals even though they didn't build any hardware that we know of, in every case they thought they could have the first production set ready for ship fitting in 1967 if they were fully funded and staffed at April 1st 1962. The aide memoire is also clear that relevant people on the RN side, Director Weapons Surface, Director Weapons Radio and the Director of ASWE knew from first contact with the Dutch side, in April/May 1961, that the Dutch radar was unsuitable for "fitting as part of a CF 299 system in a 3,000 ton ship".

The document goes on to describe the concerns about size, weight and power for the Dutch set and the work that was done to see if the Dutch set could be adapted to take the ASWE aerial they had conceived when they came up with a design scaled to meet the size, weight and power requirements of the Dutch set. As mentioned above, it was concluded that wasn't practical. Whilst the ASWE aerial proposed for retrofit to the Dutch set was based on the technology ASWE had used for its original C-band small ship proposal it was a much larger aerial and in S-band.

@zen, radar ranges are a moveable feast, it depends on target, altitude, environmental conditions and what else the radar is doing at the same time. In their Small Ship report ASWE normalised them to a range at which there was 50% probability of 'painting' a 1 sq.m. target from near the radar horizon up to 100,000 ft with half mean power available for tracking. With the successful development of a maser element for the receiver ASWE thought they could get 270nm out of their small ship set without scaling it up.
 
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The document goes on to describe the concerns about size, weight and power for the Dutch set and the work that was done to see if the Dutch set could be adapted to take the ASWE aerial they had conceived when they came up with a design scaled to meet the size, weight and power requirements of the Dutch set. As mentioned above, it was concluded that wasn't practical. Whilst the ASWE aerial proposed for retrofit to the Dutch set was based on the technology ASWE had used for its original C-band small ship proposal it was a much larger aerial and in S-band.
What was the performance of ASWE's S-Band radar?

Surely this C-band planner array is the outcome of ASWE efforts into a 3D set originally for SIGS? Just as JCF Fuller has described?
Considering the rate of progress on these things 1968 is not that surprising.
8n fact doesn't that tie in with the progress on the Type 82?


However the cylindrical system is intriguing....
Didn't the Soviets develop something like that?
ADM 220/1919
 
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The aide memoire is also clear that relevant people on the RN side, Director Weapons Surface, Director Weapons Radio and the Director of ASWE knew from first contact with the Dutch side, in April/May 1961, that the Dutch radar was unsuitable for "fitting as part of a CF 299 system in a 3,000 ton ship".
I find this rather curious, because the Dutch radar - which of course materialised as the Signaal SPS-01 - actually did go to sea on ships not quite of 3,000 tonnes, but at least significantly smaller than the Type 82. There may of course have been sacrifices made in less-obvious areas to make it work that would not have been acceptable to the Royal Navy.

In fact, the TROMP class makes an interesting comparison with the 1962 CF.299 ship studies (perhaps some of this discussion ought to be moved to that thread?) in having the 3D radar, a small-ship SAM, and standoff ASW capability. The addition of a gun and point-defence SAM presumably more than offsets the loss of the A/S mortar in terms of ship impact. I can't help wondering what was added to Type 82 that made it so much larger than the 1962 studies - 3,000 tonnes for a 4.5" Mark 8 gun definitely isn't it!
 
I understand that DAISY (SUWACO?) is less demanding than ADAWS?

I think it ran on 3 computers, suggesting one per face. But my memory (hah!) Could be wrong there.

Though I also know it's slightly later in development than ADAWS, which was inspired to handle the huge data generated by a four faced PAR Type 985.
I know that the Dutch went on a major recruitment drive for programmers during the 60's. Even poaching people from the UK.
So there could be a case here for 'riding the slipstream', and learning what not to do from earlier efforts.

I remember reading there were compromises on performance to get the FMICW set working. Can't remember where now. Google books doesn't seem to offer it up anymore.

The twin 120mm guns were recycled from older ships?

We know that Standard cost less than Sea Dart.

And we know that the Dutch opted for the UK developed powerplant.

All sums up to less cost and 'good enough' capability.
 
I understand that DAISY (SUWACO?) is less demanding than ADAWS?

I think it ran on 3 computers, suggesting one per face. But my memory (hah!) Could be wrong there.

Though I also know it's slightly later in development than ADAWS, which was inspired to handle the huge data generated by a four faced PAR Type 985.
I know that the Dutch went on a major recruitment drive for programmers during the 60's. Even poaching people from the UK.
So there could be a case here for 'riding the slipstream', and learning what not to do from earlier efforts.

I remember reading there were compromises on performance to get the FMICW set working. Can't remember where now. Google books doesn't seem to offer it up anymore.

The twin 120mm guns were recycled from older ships?

We know that Standard cost less than Sea Dart.

And we know that the Dutch opted for the UK developed powerplant.

All sums up to less cost and 'good enough' capability.
The twin 120mm may have saved money, but the mounting is considerably larger and heavier than the Mk 8.

The Type 82 has a slightly longer range and larger complement than the Tromp, which would drive up size. How do the weight and volume of Bristol's COSAG powerplant compare to that of Tromp COGAG powerplant?
 
It's not just weight which is heavier for steam, but staffing numbers would increase to operate and maintain it compared to gas turbines.
 
Size and weight drivers in the Type 82 are multiple, see here for reference to the elaborate Ikara arrangements. The Type 988 position on the Type 82 is a full deck, probably more, higher than the Tromp class which will have an impact on hull size - and the set may still not have been the 70ft above sea level that was wanted. At the point at which the British abandoned the system it would have required three Ferranti computers, I don't know what the Dutch did with the Broomstick after the British withdrawal but its entirely plausible they were able to design out some of the weight and space requirements. Then there were the flagship facilities. The adoption of the COSAG plant, in separate machinery spaces, was another major driver - itself the product of a desire for speed as well as the growing size. The Dutch ship ended up using the Olypus-Tyne machinery, but was four years behind Bristol.

With the shelving of the NIGS programme the CF.299/Ikara FSA was allowed to drift up in size and role to the point where it was a DLG, the only puzzling thing is the decision to give it an FGP type number.

At around the time SIGS came into view a NATO Basic Military Requirement was raised for a small ship guided weapons system (NBMR.11), it seems to align very closely with Admiralty thinking. I have more work to do to uncover the extent to which the British were the drivers but it seems that Germans and Dutch were looking for something similar. The requirement was for a system that was similar to Tartar but superior in performance. The outline requirements were for the simultaneous engagement of two targets at a range of 20,000 yards and the intended target types were:

1. High Level Bombers to Mach 3 at 60,000 ft
2. Low level aircraft to Mach 1.1 at 50 ft
3. Aircraft equivalent and other missiles to Mach 3
4. Ships down to Fast Patrol Boat size with speed up to 75 knots

Number 4 is the result of the intention that the system replace main guns completely in frigates and likely explains why early sketches show the ability to change the warhead to a SAP one in the checkroom. The German's ended up with Tartar and the whole thing eventually became bilateral between the British and Dutch; Dutch surveillance radar (to the obvious frustration of ASWE), British missile system and an Anglo-Dutch data handling system that had apparently begun earlier. I know very little about the data-handling system but wonder if it was essentially a small ship ADAWS with some Dutch input.
 
Just to add on Number 4, that the Admiralty by 1966 had moved to dedicated Small Ship Guided Weapon (SSGW) which was soon given up in favour of a helicopter-carried missile - which eventually became Sea Skua, although Excocet was an interim solution.
Sea Dart did have an secondary anti-ship capability but I have no idea if this was ever actually tested or even trained for in service?

Type 82 sadly was just a little too early for a good COGOG powerplant and the ships' size and displacement made it harder to get the desired speed on the engines then available.
 
So if we hadn't funded the mk8 4.5", focused on the SSSR of about 3tons instead of the Dutch FMICW with consequences for ADAWS, say simply lifted a half County or Tribal propulsion, kept SIGS say as common a system with the Army and avoided themore complex Ikara arrangement.
Then we'd have both afforded a notional Type 82, put it into serial production and achieved the costs and numbers desired?


Arguably a single 3"/L70 would have complimented this despite the cost, which ought to have been born earlier.
Though equally a anti-ship variant of the SAM would help.
 
With the shelving of the NIGS programme the CF.299/Ikara FSA was allowed to drift up in size and role to the point where it was a DLG, the only puzzling thing is the decision to give it an FGP type number.
Sounds very much like the traditional problem of 'nice-to-haves' spiralling ship size/complexity/cost upwards.
 
Just to add on Number 4, that the Admiralty by 1966 had moved to dedicated Small Ship Guided Weapon (SSGW) which was soon given up in favour of a helicopter-carried missile - which eventually became Sea Skua, although Excocet was an interim solution.
Sea Dart did have an secondary anti-ship capability but I have no idea if this was ever actually tested or even trained for in service?

Type 82 sadly was just a little too early for a good COGOG powerplant and the ships' size and displacement made it harder to get the desired speed on the engines then available.


The anti-ship mode of Sea Dart was certainly tested, one target was HMS Venus (shortly after its near devastation from a Seaslug hit) which did considerable damage; these were both end-on firings. A later firing (against HMS Rapid?) from the beam nearly sank it despite the warhead not detonating. The files are in TNA but I've lost my photos of them.
There is also another file on a dedicated anti ship version (not taken up AFAIK) with a sea-skimming mode; the file clearly shows the T42 magazine with a 20 round capacity.
DSCF1359_SeadartMagazine.png DSCF1359_SeadartMagazine.png
 
So to further compare and contrast.

Friedman's description.

Orange Nell estimate circa 1952.
10ft long missile, diameter of 10". 6ft missile and 4ft booster.
40lb warhead and total weight of 500lb, the missile being 270lb of this.
Slant range 9,700yards.
Single shot kill probability of 30% at 12,000yards, rising to 80% at minimumrange of 2,000yards.

The diagram shown by CJ Gibson.
Length 93" = 7.75ft? Or is that 9ft?
Diameter 10"
Control span 24" = 2ft
Warhead 30lb?
Guidance 20lb
Motor and blast tube 135lb
Body structure 50lb
Wings controls and actuators 15lb
Missile 270lb
Total 540lb.

Differences here could be the result of the inefficiency of wrap around boosters in terms of drag and weight.
A single tandem booster being 40lb or more less in weight. Though it also results in a larger warhead so maybe 50lb of weight reduced in using a single booster!


Description in paper shown by CJGibson
Length 9ft 9"
Diameter 12"
100lb warhead
100lb guidance
Total weight 900lb or 10,000yards
1,100lb for 15,000yards.

Presumably going on this description, a 20,000yards might add another 200lb?

This does seem to bring home the weight increases for total system weight to carry increasing weight of guidance and warhead for a given performance level.

However it seems from Friedman that the later SIGS CF299 was expected to be 768lb and use a quadruple launcher.

Would be nice to compare SIGS-16 which might be lighter. Possibly due to improvements in rocket fuel, guidance and warhead weight/performance.

Considering the potential and it's performance. The size and weight put this in a different class to Tartar.
Which was
1,310lb
Diameter of 13.5"
Length of 180" = 15ft
Warhead 130lb.
Though at the time the uk understood it would have a 100lb warhead and weigh 1,050lb all up.

Orange Nell is headed towards a lighter and smaller weapon. Which must surely make the magazine, handling gear and launcher less demanding on a ship.

If one assumes a drum magazine it ought to be install-able only one deck deep accepting a couple of feet of protrusion at worst.
 
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Both Probably, but I have a drawing showing a 'typical' missile and a report that says wrap-around is the preferred configuration

Chris
Chris, do you have a scan of the report's next page?

BR
Piotr
 
The best source on Popsy is here:


It goes into the history in some detail. I find it amusing that the ultimate outcome of Pospy was Sea Skua - very indirectly.
 

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