avatar_Weaver

Type 21G frigate

Started by Weaver, January 04, 2022, 01:09:54 AM

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Weaver

Okay, so I came up with a ship idea that fits into the gunships theme. It's best done with shipbucket profiles. Here's the starting point and a quick'n'dirty about where it's going:



The details will change as I do the profile proper: the Q'n'D was just to get the idea across, but the hull stretch WILL be done differently and it's likely other things will too. Also, the first thing I'm going to draw is the Type 21M (Ikara back end) that the 21G is derived from. The reasons for all this gunnery will become clear in the back story.
"Things need not have happened to be true. Tales and dreams are the shadow-truths that will endure when mere facts are dust and ashes, and forgot."
 - Sandman: A Midsummer Night's Dream, by Neil Gaiman

"I dunno, I'm making this up as I go."
 - Indiana Jones

Weaver

Source profiles. Note the differences between the two Type 21 profiles, done by different artists at different times.







"Things need not have happened to be true. Tales and dreams are the shadow-truths that will endure when mere facts are dust and ashes, and forgot."
 - Sandman: A Midsummer Night's Dream, by Neil Gaiman

"I dunno, I'm making this up as I go."
 - Indiana Jones

Weaver

#2
<sigh> Well, as usual, within hours of me posting my intention to make something, the rest of my life goes to hell...  Spent most of this week dealing with an admin cock-up between the doctor, the coroner and the registrar's office which meant my auntie's death nearly didn't get registered in time for the funeral... :banghead: :banghead: :banghead:

<sighs again> And also as usual, the more I look at the original Shipbucket profile that I'm basing my ideas on, then the more errors I see in it that I'm going to have to correct before I even start (although thankfully some of them were things I was going to change anyway) :banghead:
"Things need not have happened to be true. Tales and dreams are the shadow-truths that will endure when mere facts are dust and ashes, and forgot."
 - Sandman: A Midsummer Night's Dream, by Neil Gaiman

"I dunno, I'm making this up as I go."
 - Indiana Jones

PFJN

Hi,

That's a shame.  Sorry about your aunts passing.  Hope everything settles down for you soon.  Your idea sounds really interesting.

Pat

Weaver

#4
Okay, actual progress! The hull and superstructure stretches are done. I've decided to address the inaccuracies in the original profile as I go rather than up-front, since many of them will go away anyway.

A comparison of the B-gundecks on the Type 22 and Mk.10 revealed that my 20ft stretch wasn't quite enough. The backstory is that these were designed to be upgraded with one Seawolf launcher forwards when it became available, and I'm presuming that you need one Seawolf box-length of 'elbow' room between the bridge and the launcher to reload it. The hull stretch has therefore increased to 24ft, the new dimensions now being 449 x 47ft, which maintains the Mk.10's 9.6ish length-to-beam ratio. (Real Niterois were 425.1 x 44.2ft).

The stabilisers have been moved back to their original position relative to the funnel, since I presume the machinery for them is in the engine room, but the blige keels have only been moved back 12ft to keep them roughly in the centre of the hull.

"Things need not have happened to be true. Tales and dreams are the shadow-truths that will endure when mere facts are dust and ashes, and forgot."
 - Sandman: A Midsummer Night's Dream, by Neil Gaiman

"I dunno, I'm making this up as I go."
 - Indiana Jones

Thorvic

So going to try it in plastic, using an Airfix Amazon to do it in 1/700 ?
Project Cancelled SIG Secretary, specialising in post war British RN warships, RN and RAF aircraft projects. Also USN and Russian warships

Weaver

Quote from: Thorvic on January 08, 2022, 06:54:52 AM
So going to try it in plastic, using an Airfix Amazon to do it in 1/700 ?

Hmm: it works out to within a foot lengthways, although the beam would be greater:

Mk.10: 425.1 x 44.2ft  (l/b ratio: 9.62)
Stretched Mk.10: 449 x 47 ft (l/b ratio: 9.55)
Type 21: 384 x 41.8 ft (l/b ratio: 9.19)
Type 21 scaleorama'd from 1/600th to 1/700th: 448 x 48.76ft (l/b ratio: 9.19)

All the weapons, sensors and fittings would have to be 1/700th though...

"Things need not have happened to be true. Tales and dreams are the shadow-truths that will endure when mere facts are dust and ashes, and forgot."
 - Sandman: A Midsummer Night's Dream, by Neil Gaiman

"I dunno, I'm making this up as I go."
 - Indiana Jones

Thorvic

Fittings are a lot easy to get hold of in 700 scale, the sprue on a Revell/Dragon Invincible, has the MK8 vickers, Breda 40mm, sea wolf. sea cat etc
Project Cancelled SIG Secretary, specialising in post war British RN warships, RN and RAF aircraft projects. Also USN and Russian warships

Weaver

#8
Okay, here's the forward superstructure pretty much done. I was originally going to put a Type 22 bridge on it with a walkway around the front joining the wings. However it then struck me that if I moved the bridge forward in a Type 21-style setup, I could make more room for the fire-control radar (there's supposed to be enough room for a Seawolf's Type 910 there) and move the mast forward. In the end, I didn't go quite that far, instead steepening the Mk.10's slope in front of the bridge.

The Ikara radar is going elsewhere, and the 40mm guns have been replaced by 20mm Oerlikons, as per 1970s RN practice on ships with a 4.5" gun turret. The structure around the Type 912 radar and director sight is a blend of Mk.10 and Type 21 styles. I'm presuming that the 912 can control either the Seacat or the gun: I did have look at fitting two 912s but it didn't really work (too tall when they're made 'superfiring'). The Type 912 was basically an off-the-shelf (Italian) Selenia-Orion RTN-10X, which routinely controls both missiles and multiple different-calibre guns in other applications.


"Things need not have happened to be true. Tales and dreams are the shadow-truths that will endure when mere facts are dust and ashes, and forgot."
 - Sandman: A Midsummer Night's Dream, by Neil Gaiman

"I dunno, I'm making this up as I go."
 - Indiana Jones

Pellson

Quote from: Thorvic on January 08, 2022, 10:07:28 AM
Fittings are a lot easy to get hold of in 700 scale, the sprue on a Revell/Dragon Invincible, has the MK8 vickers, Breda 40mm, sea wolf. sea cat etc

I think you'll find that a Dragon Type 21 also will be in 1/600 - but with the 1/700 gear. Incredible cock-up by Dragon, but practical in this context.
Praise the Lord and pass the ammunition!

Weaver

Well having to do admin for my late aunt's estate, plus a few other things, has stolen nearly all my time in the last couple of weeks, however I have managed to get as far as getting the Type 21M finished:




Here's the original Niteroi (VT Mk.10) profile for comparison:




Now all I have to do is the Type 21G variant and write the backstory, all before midnight today... :o
"Things need not have happened to be true. Tales and dreams are the shadow-truths that will endure when mere facts are dust and ashes, and forgot."
 - Sandman: A Midsummer Night's Dream, by Neil Gaiman

"I dunno, I'm making this up as I go."
 - Indiana Jones

Weaver

#11
The Type 21G Frigate
Britain's last 'gunboat'.

The original plan for the Type 21 frigates envisaged them as cheap, commercially designed replacements for the Tribal class frigates, intended primarily as a General Purpose frigate for 'patrol and policing' role in peacetime and as a second-rate ship to bulk up numbers in a war. However, a change of staff in both the Admiralty and Whitehall, together with a little more money being made available, caused this concept to be reviewed. The wisdom of building brand-new 'second-rate' ships while at the same time converting older, smaller Leander class vessels into sophisticated 'fleet' vessels was questioned, and a revised plan produced. Under this scheme, the Type 21s would be based on the larger Vosper Thornycroft Mk.10 design, which could carry both Ikara and Exocet, with enough margin for the initial Sea Cat SAM system to be replaced by the newer Sea Wolf system in due course. Meanwhile, all 16 Narrow-Beam Leanders would receive the rather simpler 'Exocet Leander' conversion, while the 10 Broad-Beam Leanders would be converted to the GP role, in a configuration generally similar to the Chilean export ships, with Exocets replacing the VDS at the stern, an extended helideck for a Lynx, triple torpedo tubes replacing Limbo, and the 4.5" guns being retained.

The new Type 21s mounted a 4.5" Mk.8 gun forwards, fore and aft Sea Cat systems (the intention being to replace at the least the forward one with Sea Wolf when it became available), Ikara aft and four MM38 Exocet launchers right aft. A Lynx helicopter, STWS-1 torpedo tubes and a pair of 20mm guns completing the fit. Eight vessels were built, commissioning between 1974 and 1978:

HMS Amazon F169
HMS Antelope F170
HMS Active F171
HMS Ambuscade F172
HMS Arrow F173
HMS Alacrity F174
HMS Ardent F184
HMS Avenger F185



Then in 1976, the Gulf of Sirte incident happened. Three NATO warships, patrolling in international, but disputed, waters off the Libyan coast, were attacked by three Tu-16 Badger aircraft which launched two AS-5 'Kelt' missiles at each of the ships. The results were not at all encouraging for the missile-based defence theories of most of the major navies. The USS Theophilus P. Wilderbeest, a brand new US Navy Spruance class destroyer, engaged the incoming missiles with Sea Sparrow, hit one, missed the other, and took a devastating hit which killed 34 of her crew and injured three times that number. Subsequent damage control efforts were less than satisfactory, and her captain went on record as stating that only her large size had prevented her from sinking. The accompanying Royal Navy frigate HMS Tyche only avoided proving that point by the narrowest of margins. She turned away from the attack, launched chaff and engaged with Sea Cat. One of the incoming missiles crashed, presumably due to a technical fault, and Sea Cat missed the other one, but it in turn missed the ship. The chaff cloud, having had just enough time to form, caused the missile to pass down the side of the ship at an estimated distance of 30 feet. The surprise of the afternoon however, came from the third ship, the Italian Alpino class frigate Canneloni. Despite lacking any sort of SAM system, she put up a murderous barrage from her rapid-fire 76mm guns and not only downed both missiles heading for her, but did so at a comfortable distance.

These events served to change the Royal Navy's long-standing prejudice against anti-aircraft guns. Whilst they still felt the optimum solution was to accelerate the Sea Wolf programme, they now looked in earnest for ways to fit as many ships as possible with modern AAA systems, replacing Sea Cat wherever possible. Of particular concern were the new Type 42 destroyers, whose very tight design meant that new AA guns couldn't just be added to them. Instead, the decision was made to replace their 4.5" Mk.8 guns with Breda-Bofors twin 40mm gun turrets. This however, brought to a head another concern that had been brewing since the decision to abandon the Tiger class cruiser conversions and remove 4.5" Mk.6 gun turrets from the County class destroyers and the Leanders. That concern was naval gunfire support (NGS). The forthcoming Type 22 frigates would have no guns, which meant that the only modern DP guns in the fleet long-term would be the Mk.8s on the eight Type 21s. Clearly, something needed to be done.

The solution came from Vosper Thornycroft. On the back of the Royal Navy order, they'd had a profitable run of export sales for the Mk.10, including six for Brazil, of which two were a GP version with two Mk.8 guns. Argentina had ordered four of a modified version of this design which featured two twin 40mm gun turrets in place of the Brazilian ships' hangar-roof mounted Sea Cats, but had then cancelled the order, after VT had laid the first one down, choosing instead to buy a pair of Type 42 destroyers. VT pointed out that if the Argentine aft gun arrangement was combined with the replacement of the forward Sea Cat by a twin 40mm, the resultant ship would meet all the new RN requirements for both AAA and NGS, and what's more the ships could be delivered relatively quickly, since VT had already assembled a considerable amount of material for them. The Royal Navy concurred, and ordered four of the modified ships as the Type 21G ('G for guns') class, the previous Type 21s being redesignated Type 21M ('M for missile').

The Type 21Gs entered service between 1979 and 1982. They had two Mk.8 4.5" guns located fore and aft, and three Breda-Bofors twin 40mm turrets. One of the latter stood on a new deckhouse on B-gundeck, replacing Sea Cat, while the other two sat side-by-side on a much modified hangar structure, which in turn required the torpedo tubes to be moved down to flight deck level. To give the aft Mk.8 turret full aiming arcs, the Exocets were moved to an amidships position similar to the Brazilian GP ships, displacing the Corvus chaff launchers which were relocated on B-gundeck between the bridge and the 40mm turret. The ships carried the same pair of Type 912 (Selenia-Orion RTN-10X) fire control radars as the earlier Type 21s, but the fire control system was replaced by a modified Italian Selenia-Orion one, which would engage air targets with the 4.5" guns at longer ranges, switching automatically to the 40mm weapons as the range closed. The four ships were:

HMS Abercrombie (F186)
Comemorating General Sir Ralph Abercrombie, this name was deemed appropriate since it had been used previously for two Royal Navy monitors: ships intended primarily for shore bombardment, albeit with much bigger guns.

HMS Amethyst (F116)
This ship (and it's out-of-sequence pennant number) were named to honor the Black Swan class sloop of the same name that was involved in the famous Yangtse Incident, in which she fought several duels with Chinese Communist shore batteries.

HMS Atlantis (F187)
This name had previously been allocated to a P-class submarine, the order for which was cancelled in 1945.

HMS Avalon (F188)
This name had previously belonged to a Royal Navy shore establishment in Canada, which had since been handed over to the Royal Canadian Navy and renamed.



Seven of the Type 21Ms and three of the Type 21Gs served in the Falklands war, Amazon and Abercrombie being in refit at the time, and Avalon being rushed through her acceptance trials at the last minute. The Type 21Gs proved as useful as had been expected, conducting a large proportion of all the task force NGS missions. On the 20th of May, Avalon was in Grantham Sound, conducting NGS in support of the attack on Goose Green, when she was attacked by no less than four successive waves of Argentine aircraft. However she defended herself successfully, despite having some problems getting fire-control locks on aircraft approaching over land. In total, Avalon managed to shoot down two Pucaras, three Skyhawks and a Dagger while only taking minor damage and light casualties from near-misses and cannon-fire. The near-misses did cause some leaks which proved difficult to fully repair in theatre however, and she was subsequently sent back to the UK before the end of the conflict. Three days later Antelope, a ship which had not yet received the much-delayed conversion from Sea Cat to Sea Wolf, was attacked in Falkland Sound with very different results. The only attacker downed was a Skyhawk that was hit by 20mm fire and subsequently collided with the ship's mast, although another Skyhawk was damaged by a Sea Cat and had to be nursed home. In return the Skyhawks managed to plant two 1000lb bombs in the frigate, both of which failed to explode. However, during subsequent attempts by an EOD team to defuse the bombs, one of them did explode, killing one member of the team and seriously injuring another. The subsequent fire proved unmanageable with the ship in it's damaged condition, and the decision was taken to evacute it and leave it to burn out. Antelope finally sank in the early hours of the next morning, following several massive explosions caused by the fire reaching the magazines. On the 12th of June, Amethyst and the County class destroyer Glamorgan were in the same area as each other, both coming off different NGS missions, when the latter was attacked by an Exocet missile fired from an improvised launcher on the shore. Glamorgan's Sea Cat missed the Exocet, and the ship took the hit, which didn't result in her loss, but did kill 13 of her crew and injured many more. As Amethyst went to Glamorgan's aid, she was attacked by another Exocet from the same source, however she responded with a barrage of 4.5" and 40mm fire which succeeded in destroying the missile. Amethyst then closed the range a little and returned fire with her 4.5" guns, doing some damage to the launchers and causing the crew to abandon them. it was believed at the time that this action had silenced the battery, although it was revealed post-war that the battery had, in fact, only been lightly damaged and was abandoned principally because it had fired all it's available Exocets, so the crew had little reason to stick around.

These three actions were seen as vindicating the decision to adopt modern AAA guns and all subsequent RN ship classes were so equipped. During the 1980s, the remaining Type 21Ms had their forward Sea Cat launchers replaced by Sea Wolf as planned, but Sea Wolf had grown in size and weight to the point where it couldn't replace the aft Sea Cat. Rebuilding the hanger block to the Type 21G design was seen as too complicated and expensive, so the aft Sea Cat and Type 912 director were replaced by a BMARC GCM30-A03 twin 30mm mounting controlled by a Marconi ST802 director. The Type 21Gs couldn't be similarly converted for Sea Wolf since their internal arrangements had been changed too much from the original Type 21 design in order to accomodate the 40mm guns, so they retained the latter to the end of their service life. This came earlier than expected in the mid 1990s, as post-Cold-War force reductions saw all the Type 21s being sold off to other navies, the Type 21Ms going to Brazil and the Type 21Gs to Pakistan.
"Things need not have happened to be true. Tales and dreams are the shadow-truths that will endure when mere facts are dust and ashes, and forgot."
 - Sandman: A Midsummer Night's Dream, by Neil Gaiman

"I dunno, I'm making this up as I go."
 - Indiana Jones

Old Wombat

Very nice! :thumbsup:

I do like guns on my ships. ;D
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Rheged

YES!!   Both the design and the backstory will do very nicely!
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