Missile launching turrets for Battleship or Battlecruiser

[ysi_maniac]

I ask you to suggest ideas about this issue. I posted some drawings to suggest you too.

[Weaver]

Funny this should come up: I was thinking about something similar just a few days ago.

One thing to consider is the nature of the pre-launch handling that your chosen missile requires. A lot of 1950s/1960s missiles had to be delivered to a handling+checkout room before they could go the launcher. Here, wings and fins were fitted and the missile's delicate transistor/valve electronics tested before they moved on the launcher. Provision also had to be made to return unwanted or misbehaving missiles to the magazine, or to a workshop area where they could be dealt with. All this means that many missile installations had a very different shape to turret barbettes, being either long and horizontal (like aircraft hangars), or "r-shaped" with the handling room and/or launcher not located above the deep magazine. Drum-shaped missile magazines like the Mk.11/13 were the exception, not the rule.

I was looking at this because I was looking at ways of fitting Ikara to a British Tiger-class cruiser, and it ocurred to me that, since the missile is relatively stubby, you might be able to concoct a system where the handling room and launcher occupy a rotating turret that replaces the twin 6" turret. I eventually decided that it was more trouble than it was worth, and you've better off just using an Ikara Leander-style installation with the handling room in place of the turret and the launcher either in front of it in a zareba or behind it in the former 3" turret's gun room.

Shipbucket's parts sheets have a number of drawings that show the below-decks parts of missile launchers and gun turrets, and are very instructive. I've thrown this together from a number of sheets, so sorry for the disorganization. Scale is 2 pixels = 1 foot.

[PR19_Kit]

The size of the Seaslug installation BOGGLES the mind. No wonder the Counties were so large.

[Gondor]

I so wish that somone could or has done something simmilar with Brittish ships radars post WWII as I have no idea what to put where on the three whiff ships I have.

Gondor

[Weaver]

I so wish that somone could or has done something simmilar with Brittish ships radars post WWII as I have no idea what to put where on the three whiff ships I have.

Gondor

Ask and ye shall receive...

This isn't the whole story though. For instance, it shows the dome for the Type 909 Seadart fire-control radar, but it doesn't show the cabin ("office") it sits on that was a non-negotiable part of the installation. The transceiver components actually hung from the underside of the turntable and rotated with the aerial, so if you see a Shipbucket profile that has the dome on a platform at the top of a mast or on the bridge roof (and they exist) then you know somebody hasn't done the research...

I'm pretty well up on this stuff now so if you want to run your ideas/problems past me I'd be happy to advise (as long as lawyers aren't involved)... (or real shells/missiles/torpedoes etc...)...

[Gondor]

Thanks very much Weaver. I can see a lot of PM's in the future, as I really should get a few other projects ouot of the way 

Gondor

[ysi_maniac]

Thanks for posting such amount of information.

[rickshaw]

The Australian Navy's Ikara set up was different to the RN's.  Basically it was a single deck with armoured compartments and on either side of the ship was a launcher.  The launchers were amidships.  The missiles were moved along a track from compartment to compartment and then to the launcher.  The launcher only had limited 180 degree's training and the missile guidance system was expected to handle the fine tuning on the heading selected.   They were also as far as I know, electrically trained and elevated systems, unlike the RN's installation which used hydraulic motors which were extremely noisy and could alert a submarine in the vicinity.  The RN decided they had to have "positive control" over the missile at all times because the missile was intended to carry nuclear depth charges instead of a torpedo.  The RAN was happy with torpedoes so they didn't care about it as much.

With radars, generally you would have three or more different aerials for the systems.  At the top, you would have air search radar, below that, height finding radar and then below that, surface search radars.   It was only on the fourth layer that weapon direction radars sat.   The top most aerial at the widest view and the greatest range.  Once it had acquired a target, then the height finder would be used to determine it's height.  Surface search radar and a relatively poor view of the surrounding ocean but as it's range was limited, that didn't matter as much.

[PR19_Kit]

unlike the RN's installation which used hydraulic motors which were extremely noisy and could alert a submarine in the vicinity.

Indeed, the RN, or rather the Royal Corps of Naval Architects, were wedded to Lucas stuff for their hydraulics, and never used quiet porting for some reason. In the 70s they switched to Fairey Hydraulics, which came with quiet ports as standard.

Nowadays they're all electric of course.

[Weaver]

The Australian Navy's Ikara set up was different to the RN's.  Basically it was a single deck with armoured compartments and on either side of the ship was a launcher.  The launchers were amidships.  The missiles were moved along a track from compartment to compartment and then to the launcher.  The launcher only had limited 180 degree's training and the missile guidance system was expected to handle the fine tuning on the heading selected.   They were also as far as I know, electrically trained and elevated systems, unlike the RN's installation which used hydraulic motors which were extremely noisy and could alert a submarine in the vicinity. The RN decided they had to have "positive control" over the missile at all times because the missile was intended to carry nuclear depth charges instead of a torpedo.  The RAN was happy with torpedoes so they didn't care about it as much.

That's the setup on the Perth-class destroyers. they carried the Ikaras amidships because that's where the Charles F. Adams class destroyers they were based on carried their ASROC launcher.

On the River class frigates, the setup was different. The first four Rivers were based on the RN's Type 12 design and were built with two Limbo mortars and an open quarterdeck. When they were refitted, the Ikara magazine replaced the forward Limbo, the handing room sat alongside the aft Limbo opposite it's reloading room, and the launcher sat on the starboard side of the quarterdeck. The port side of the quarterdeck was built up with a windowed cabin, apparently to control a variable-depth sonar setup, although I'm not sure if they ever got the actual equipment.

The last two Rivers, Swann and Torrens, were based on the Type 12I Leander design, and had Ikara from new. The position was the same as on the earlier Rivers, but because the Leander hull didn't have an open quarterdeck, the launcher was now in a cutout on the starboard side of the hull.

All Ikara launchers fired at a fixed elevation angle of 55 deg. The electric RAN launcher only trained in 45 deg steps, but the hydraulic RN launcher was pointable to minutes of angle. Completely pointless exercise since the missile was basically a relatively slow radio-controlled plane that could be steered onto it's precise heading after launch.

The RN's belief/hope that they were going to get nuclear depth bombs for their Ikaras influenced the whole RN system. Firstly, there was the launcher redesign already discussed. Then there was the magazine: the RAN was happy with a magazine that wasn't accessible while the ship was underway, but the RN needed to get at the missiles in order to swap a torpedo for a nuke. The installation on Leanders had the missiles stored vertically in two rows with a passageway between them. Each missile was picked up by a manually-operated overhead hoist on a monorail, and then taken to the end of the compartment where it was placed on a hoist and elevated to the handling room. That, by the way, is the reason why the RN handling room is so tall: if you've got 11 foot long missiles arriving vertically through the floor, then you need a 12 foot ceiling (at least). I've never see a definitive drawing of what Bristol's Ikara setup looked like below decks. Some sketches show that setup in the Shipbucket drawing, but they're preliminary sketches not blueprints, and they contain many other details that changed before building started.

With radars, generally you would have three or more different aerials for the systems.  At the top, you would have air search radar, below that, height finding radar and then below that, surface search radars.   It was only on the fourth layer that weapon direction radars sat.   The top most aerial at the widest view and the greatest range.  Once it had acquired a target, then the height finder would be used to determine it's height.  Surface search radar and a relatively poor view of the surrounding ocean but as it's range was limited, that didn't matter as much.

There's a bit more variation than that, depending which navy you're looking at and when.

Many navies, including the RN, split the air-search task between two radars with different characteristics:

The Air Surveillance radar was a very long range but very slow-scanning and imprecise set, giving a 'broad brush and washy colours' picture of the biggest possible volume of airspace. To give you an idea, Type 965 AKE1's aerial had a seventeen degree beamwidth  and even the AKE2 serial only got that down to twelve degrees. This wasn't remotely precise enough to feed into the Combat Information System (AIO - Action Information Organisation in RN language), so it was mainly gave an early heads-up and provided 'air-traffic-control radar' for the ship's fighter-controllers.

The Target Indication radar was a much higher frequency set with a narrow beamwidth and a higher scan rate, but the pricve it paid for this was range. The Type 992Q used in the '50s to '80s had a range of about 90 miles. It's one degree beamwidth was plenty accurate enuogh though, so this was the main source of information for the AIO to update it's target tracks from, prior to handing a target over to a fire-control radar. TI radar also usually includes a surface-search function, and may be called a 'low-level air/sea serach radar' in some navies.

Although the Air Surveillance radar was the longest range set, it wasn't always mounted the highest, since it also had the largest and heaviest aerial. On most RN ships, the smalled TI radar was mounted higher.

Dedicated height-finding radars were common from WWII until the 1960s, but they died out when navies realised they could get the same functionality by swinging a fire-control radar onto the bearing and then sweeping it up and down to get the height. Modern ships are chronically short of topspace for radars and weapons, so anything that doesn't earn it's keep is history.

All this went by the board in two waves. Firstly it became possible to build '3D' radars that both swept a large volume of sky AND gave precision in bearing and height. These still had mechanically-scanned aerials, but they used various forms of electronic manipulation to form tight beams and sweep them vertically. The flat, square, slatted 'washboard' aerials you seen on many older USN ships work on this principle. Then, of course, increasing computer power made Active Phased Array radars possible (the SPY-1 of the USN's AEGIS system being the prime example), and these have, in one form or another, made all the older sets obsolete. They either have multiple fixed arrays or one big array that can be rotated or pointed selectively, and these arrays consist of thousands of small fixed aerials which transmit in complex patterns under computer control, the beams being formed by the constructive interference patterns between the individual signals.

Phased Array radars can literally make any number and type of beam they want and change it instantly, so they can be any and every type of search radar you need at the push of a button. If your SAMs have active homing and therefore don't need target illumination, then you don't need fire-control radars either, and we might finally be approaching the era of the 'one-radar-warship' (which is great until it breaks down, of course...).

[NARSES2]

Then there was the magazine: the RAN was happy with a magazine that wasn't accessible while the ship was underway, but the RN needed to get at the missiles in order to swap a torpedo for a nuke.

I'm obviously missing something mate, but what's the point of having a magazine you can't access ? Or were the reloads to be automatic ?

[Weaver]

Then there was the magazine: the RAN was happy with a magazine that wasn't accessible while the ship was underway, but the RN needed to get at the missiles in order to swap a torpedo for a nuke.

I'm obviously missing something mate, but what's the point of having a magazine you can't access ? Or were the reloads to be automatic ?

There wasn't enough room in the magazine, when it was full, for a man to go in there and change a torpedo for a nuke, or a dodgy torpedo for a good one. The magazine held the missiles on a powered overhead conveyor-belt system which could shuffle them around to the point where they were next to the handling room doors. They were then slid into the handling room, where sailors attached the fins and checked out the electronics, before being slid out of the opposite door onto the launcher. I presume that loading was the reverse of unloading, i.e. new missiles were backed, one-by-one, into the loading room first, and from there transferred to the magazine.

You couldn't swap a torpedo for a nuke in the handling room as designed, because the missile was resting on a cradle and the payload was underneath it. I don't see any reason in principle why the handling room couldn't have been redesigned to make it possible though.

[rickshaw]

The RAN's River Class were frigates, not destroyers.  They were a bit of an odd bunch with the first four completely different to the latter two.  They were originally designed with two twin 4.5in gun turrets, a quaduple 40mm Bofors and two Limbo ASW mortar systems.  During their lives they underwent various refits with first the 40mm Bofors being replaced with Seacat SAM launchers and then their forward Limbo and then later their aft Limbo launchers being removed.  The initial four were based on the British Type 12M (or Rothesay-class) frigate design with the later two on the Leander Type 12I.

The Limbo launchers were replaced with Ikara on the quarter deck or variable depth sonar systems.  Not all ships had the variable depth sonar systems, only Stuart and Derwent having that work done.  The Type 199 Sonar system was later removed.  Voyager was lost early on in collision with the Melbourne carrier.

You're right about the radars.  I was just supplying a brief overview.  The positions can vary but generally what I said was correct for most earlier radars.

[Weaver]

The RAN's River Class were frigates, not destroyers.  They were a bit of an odd bunch with the first four completely different to the latter two.  They were originally designed with two twin 4.5in gun turrets, a quaduple 40mm Bofors and two Limbo ASW mortar systems.  During their lives they underwent various refits with first the 40mm Bofors being replaced with Seacat SAM launchers and then their forward Limbo and then later their aft Limbo launchers being removed.  The initial four were based on the British Type 12M (or Rothesay-class) frigate design with the later two on the Leander Type 12I.

The Limbo launchers were replaced with Ikara on the quarter deck or variable depth sonar systems.  Not all ships had the variable depth sonar systems, only Stuart and Derwent having that work done.  The Type 199 Sonar system was later removed.  Voyager was lost early on in collision with the Melbourne carrier.

I described the Rivers as frigates in my post, although interestingly, the RAN used US-style nomenclature for them at first, calling them 'Destroyer Escorts' and giving them DE-series pennant numbers. They later reverted to 'frigate' and renumbered them accordingly.

The first four were closely based on the Type 12M Rothsey design but with some differences. They had one twin 4.5" Mk 6 turret, one twin 40mm Bofors, two Limbos and Dutch radar as built. During refits, Seacat replaced the Bofors and Ikara replaced the forward Limbo. Some ships were fitted with triple TTs and some lost their second Limbo, but I'm not clear on which ships and when.

The last two were based on the Type 12I Leander design, but with significant differences from new. They had one twin 4.5" Mk 6 turret, one Seacat, one Ikara, one Limbo, Dutch radar and no helicopter. They were ordered later, to the improved design, as replacements for HMAS Voyager which had been lost as a result of the collision with Melbourne.

Voyager wasn't a River class, she was a modified Daring class destroyer, sister ship to Vendetta and Vampire.

[NARSES2]

Cheers for answering my question H