RN Nuclear NIGS ship

[JFC Fuller]

Oil-fired superheat lets you run superheated steam, which PWRs can't do, so gets you theoretically better performance from your neutrons but you're dependent on having oil fuel for good performance. It does seem to be what the Soviets did, and is probably the best way to do CONAS.

Separate boilers feeding the same turbines requires that the turbines run on saturated steam, which is an inefficient way to burn oil fuel and not great for turbines. Nuclear plants deal with this because they have to, and because fuel efficiency is less of a concern for them. AFAIK this is how the West thought the Soviet CONAS plants worked, but it seems to just be bad.

Entirely separate oil-fired and nuclear plants geared onto the same shaft adds a whole bunch of weight and complexity, but makes the plant design and operation effectively independent. At this point, you've just got an oil-fired boost plant. CONAG is a much lighter way to do that.

If the RN was talking about a 20,000 shp nuclear plant and a 20,000 shp steam plant, I suspect they were thinking in terms of the third option.

I can't say exactly how the 50/50 CONAS plant would have worked but I am certain that it was an option considered only briefly under a much wider nuclear propulsion study. The study that was ongoing at the time ultimately concluded that CONAG would be the optimum solution for a 75,000 SHP plant for guided missile destroyers. Specifically, a single reactor delivering 60,000 SHP and two 7,500 SHP G6 gas turbines to provide emergency power, rapid start-up and boost from 80% power to 100% power. The logic was:

1. The nuclear part of the system was heavy, anything to make it lighter was good, e.g. having alternative emergency power meant only one reactor was needed and using the Gas Turbines for boost meant that the single reactor could be smaller and lighter
2. The study assumed the ship had a double bottom, the double bottom would have to be filled with liquid anyway so that liquid may as well be fuel
3. Like conventional boilers, nuclear reactors were slow to raise steam, adding gas turbines solved for this, allowing the ship to get underway faster

As you point out, PWRs couldn't produce superheated steam. There was a view that a gas cooled reactor, specifically a CO2 cooled, graphite moderated reactor, would offer a lighter weight solution that could produce steam comparable to modern oil fired boilers. This would require more work but might be a practical proposition in the future. The added advantage of the gas cooled reactor was that further development would support a path to a gas cooled reactor connected directly to a closed cycle gas turbine, that being considered the ultimate power reactor at the time. The downside was the need for much greater pumping power to circulate the coolant than was necessary for a PWR.

Note that this was all 1956-58.

 

[Yellow Palace]

Specifically, a single reactor capable of delivering 60,000 SHP and two 7,500 SHP G6 gas turbines to provide emergency power, rapid start-up and boost from 10% power to 100% power.

I suspect it didn't hurt that a 60,000 shp reactor is also a convenient size for an aircraft carrier plant. Whether anyone wrote that down at the time is another matter....

 

[Tzoli]

I've acquired the ADM 220/2179 (Sub title: PROPOSALS FOR A LONG RANGE (UP TO 100 n.m.) G.M. SYSTEM OF HIGH CAPACITY) document and currently typing it into a word so you guys could read it. Sadly it has not a single mention of NIGS or SIGS though it describes basically the requirements and desires which resulted in the start of developing the NIGS and SIGS. It maybe be of interest to some of you but looks like it is not useful to me at all. No data on the missile, the launchers or the ship proposals to carry it. Only a vague mention that the first system should be tested on a light fleet carrier.
The document dated 1955 and based on Friedman's description it should had contained the important NIGS warship proposals...

Does the missile project names Red Shoes and Red Duster rings a bell for anybody?

 

[Hood]

I'm not too surprised, the date looked a little early for NIGS, even predates Blue Envoy.

Red Shoes = Thunderbird
Red Duster = Bloodhound

 

[Tzoli]

Yeah I've noticed...
And reading the description for the launchers:

11. LAUNCHERS

It is strongly recommended that fixed zero length launchers should be used in view of the extra weight, complexity and power requirements of the trainable ones. This subject to the provisos outlined in the section on low altitude attack.

It is recommended that the ship should be able to launch at a rate of up to about 10 per minute and that this be obtained by using about 6 launchers, each supplied from a warehouse type stowage.

In order to meet possible changes in future missile dimensions, it is desirable that as far as possible the greatest flexibility should be used in the design of missile stowage and handling equipment.

This basically describes the GW 70-81 design series. Which had various (2-4-5-6-10 single) Stage 1 3/4 missile launchers.

 

[JFC Fuller]

ADM 220/2179 immediately predates the RN adopting Blue Envoy as its next generation long range SAM. Blue Envoy was adopted instead to meet the same basic requirement. NIGS came about because of the cancellation of Blue Envoy. I’m skeptical that the RN would have ultimately used Blue Envoy had it not have been cancelled, it was atrociously designed from the perspective of ship fitting.

 

[Tzoli]

Does anybody have Document ID's which contain these drawings?

 

[Tzoli]

A very interesting discovery.

I have always suspected that Type 985 was separate from the the NSR proposed for NIGS and I think this proves it.

Whatever system GW59 was designed around in 1955 could be considered as the first step on the path to NIGS. It has several similar features;
Multiple single-arm launchers - the Admiralty/ Ministry of Aviation Working Party in 1959 felt that single-arm launchers the right solution and they even discussed having separate high-angle and low-angle launchers, presumably to save power requirements for rapid elevation etc. How this would work in practice I'm not sure without a highly complicated magazine arrangement.

Sea Slug - GW59 only has 28 missiles (3.5 per launcher!) but the missiles seem to be Sea Slug as no other name is provided only non-Sea Slug missiles seemed to be named.

Type 985 - is a search and tracking radar, presumably one radar, sounds very similar in concept to NSR but must have been more than a speculative project in June 1955 as it was assigned a Type number. Two things stand out, the equipment weight for the ship is only 740 tons, some 300 tons lighter than the other GW designs around it and it needs a Type 992 target indication radar. So whatever the Type 985 is, its not a totally standalone system and its not very big. Maybe the Type 985 really is just a digital 984 with guidance added in?

Tonnage - interestingly GW59 is 10,500 tons and yet NIGS was meant to fit on a 6,000 ton hull, this indicates either more miniaturisation of the radar and missile for NIGS or wishful thinking in 1959! But at 540ft long, GW59 is almost County sized.

The other GW ships are interesting too;
GW61 to GW 63 have the mysterious 8 launchers for 32 "R.F." missiles, 1x Trackwell radar. What is interesting is that both ships are far larger than GW59 at 15,000-16,000 tons and 610-640ft long (County was 520ft). No other radar is specified at all, not even a basic Type 974 for navigation. I find this somewhat odd as all the other designs have other radar sensors listed.
Whatever Trackwell is it must be powerful, note that Type 985 on GW985 may be a search/track radar but still needs a Type 992Q for targeting info. Trackwell seems to be able to operate without it. If this is a track/scan radar then it predates the AN/SPG-59 by at least 3 years so cutting edge indeed. At 1,090 tons equipment weight for all 3 GW designs, it seems Trackwell is a large and heavy piece of kit contributing to the weight.

GW70 to GW78 all have the Bristol 1 3/4. Nearly all have 6x T.I.A., 7 of the ships have a dedicated telemetry link, 6 of the ships have a Beacon and oddly GW 72 and GW73 only have the beacon and no T.I.A.! Regardless of the gun armament options, all of these are big and heavy ships of cruiser size.

My money is on the R.F. and Trackwell being a proto-NIGS system, it looks a capable and heavy system and close to the things the 1959 working party were talking about. Whatever 985 is, it doesn't seem quite in the same league. NIGS seems to have followed the Bristol 1 3/4 system and added illuminators too.

My questions are:
Why was Type 985 not used on any other GW ship or with the R.F. missile system and was it really just linked to Sea Slug?
What is the R.F. missile?
What is Trackwell?
What is the T.I.A tracker?
Why where the Navy looking at essentially 3 different systems at the same time (Sea Slug with 985, R.F with Trackwell, Bristol Blue Envoy with 984 & TIAs)

To answer Tzoli's question;
NIGS = New Naval Guided Weapons System

Regarding Beacon I've found mentioning this word in the archives and the year is close to the GW series time frame:

Intermittent beam riding: a single beacon system using a surveillance radar beam​

Intermittent beam riding: a single beacon system using a surveillance radar beam | The National Archives

The official archive of the UK government. Our vision is to lead and transform information management, guarantee the survival of today's information for tomorrow and bring history to life for everyone.

discovery.nationalarchives.gov.uk

Another one which might or might not related:

RADAR and RADIO COUNTERMEASURES (Code B, 61): Ultra Search and Rescue Beacon (SARAH)​

RADAR and RADIO COUNTERMEASURES (Code B, 61): Ultra Search and Rescue Beacon (SARAH):... | The National Archives

The official archive of the UK government. Our vision is to lead and transform information management, guarantee the survival of today's information for tomorrow and bring history to life for everyone.

discovery.nationalarchives.gov.uk

Sadly no mention of Trackwell or Track Well or TIA

 

[zen]

Necromancy because of pondering.

For the bulk of a missile's flight, it doesn't really need a constant guidance from the ship. Especially once we introduce autopilot of some sort.
Which is true for both Beam Riding and SARH.
So in theory, the missile could just recieve updates at regular intervals.
It's only on closure with the target that either such updates need to increasingly become continuous, or that the missile switches to self guidance.

Beacon seems an attempt at just this, and this explains why it's sometimes included with Type 985 and TIA, and sometimes with just Type 985 or even older sets like Type 984 or the 982/983 (which became in updates 986/987) combination.