The economics of providing a mobile airfield say you end up with more aircraft and more non mobile airfields for the same money. How much depends on the various sizes and things like how many ports the carrier is expected to operate from, each requiring a nearby airfield. In money terms the carrier is either giving capabilities beyond the land based airpower, so a supplement or an economically inefficient substitute. A scenario has been defined that is so clear to the writer, it is assumed everyone else fully understands it without much explanation
What you are missing is that I did NOT ask anyone to understand it, care about it, think about it, or write about it through the heavens blazing trails of glory. I wrote ONE sentence about it to explain why I was asking an arcane question about a possible modification. That's all.
If I had been asking for comment on the scenario I would have presented it properly so that everyone could understand it. Since I was not, I did not.
Actually it did, unless the idea is to leave parts of the country undefended.
The intention is just the same as the US, UK and Japan had with their carriers. The carrier arm is not the basis, or the major component, of the air defence of the homeland.
Correct about the one place, I confused that with the carrier, in fact the scenario is pushing costs onto the alternative to the carrier by requiring a network of land bases.
I didn't say a carrier in this situation needs more than one base. It would have an operating radius of about 1800nm from that base without further logistical support, bringing the radius of its aircraft to almost 2000 miles.
To get similar radius of potential action, a land based squadron would typically need three bases. That racks up the costs.
More aircraft require more bases is quite logical, but when comparing costs each carrier capable port comes with an airfield, two ports, two airfields, plenty of room for more aircraft bought with the carrier money. In simple terms the more airfields the country needs the more ports.
The carrier, with the majority of the fleet, is normally based some 30nm south of the most populous city which is at -20.211339, 159.138710.
I confess I don't understand why "each carrier capable port comes with an airfield, two ports, two airfields…". There are obviously typos there because each airfield can't come with two airfield and each port can't come with two ports.
The geography of this area is that of the Chesterfield Rise and Fair Way Rise both lifted 2000m and with detailed topography, settlement, etc lifted from other real parts of the modern world and slightly adapted. I adopted it for a completely unrelated AU/ATL, a sporting one, and I'm maintaining the same settlements, geography etc so I don't make everything too convenient - however it is quite convenient for defence.
The main naval port on the east shore of the largest (central) island sitting on Chesterfield Rise, where the strait between the main island and the eastern one (which is Fair Way Rise elevated) is just 55m. The main national naval air base is about 40m south of the main naval base and for emergencies/overflows etc there is a small (450m) strip within a mile of the main naval base as well as the major commercial airport 14m NW of the main naval base. The major exercise area is off the major national naval air base. The details come from the real facts of the areas lifted from the real world to detail the ATL world within the basic Chesterfield/Fair Way outline.
Because the main naval base is very central to the main two islands and because of the geography, there's no need for any other true carrier-capable port on the main two islands. From the ocean off the other main coastal cities of the main island (CF) it's only 100m back to the main base and there would be emergency strips scattered around, so there is no problem if the conditions require calmer seas.
460x360 = 165,000 square miles, which does not seem to cover the area of the surrounding ocean where an enemy carrier force could be. And a solution to this is a carrier operating aircraft with a 150 mile combat radius? It seems part of the idea is the carrier will substitute for 4 or more land airfields in order to be the cheaper alternative, or else be so balance tipping no to few attacks are made on the country, or else the carrier is an add on, not a substitute and comes out of a different budget.
The carrier is like other carriers - a flexible and valuable arm of the fleet. This is a country that has been working with the Commonwealth for decades in an environment where the Singapore Strategy exists, with its own far-flung islands, and which does not want to ignore these wider responsibilities. Nor does it want itself to be cut off by a force as small as say a Kongo and Ryujo with escorts, taking turns with 8" cruisers and Hosho to cut the nation off from the south.
Without a carrier, the entire nation can be cut off. With a carrier, it can at least run convoys in and out. It seems bizarre to allow an entire nation's fate to hinge on the fact that you don't want a properly-balanced force that can exert power more than 550m from the shores.
The bigger the area the more the carrier will need more alternative bases than in most combat situations, with associated airfields, allocate the costs and constraints to both forces, not just one. Add the costs to both forces.
Look, for example, at the Med. For much of the time the RN had one base at Gib, one base at Malta sometimes available, and one at Alex. So that's one base every 1100 miles or so. A bunch of early-war landplanes are not going to be able to offer the flexibility to move across that sort of area with only one airfield.
Look at the careers of the armoured carriers - some of them operated from the Arctic, through much of the Atlantic, in the Mediterranean, the Indian Ocean and then the Pacific. How many airfields do you need to achieve a similar span of action with land based aircraft?
Actually I am trying to compare like with like, all the above missions air air ones, the carrier mission to operate beyond land based air cover requires adding the cost of the system to enable the carrier force to know where to go to find raiders.
But that cost has to be paid anyway, even if you don't have a carrier. Cruisers will be sent out if there is no carrier.
Also what trade route distances need to be covered, one carrier can cover 1 trade route, so how many routes? Submarines in particular will be operating all around an island nation under attack.
Geoffrey, do you think others are not aware of factors like the existence of submarines? I posted a thread asking about Sea Hurricane radiator scoops. Why on earth am I now being asked to set out something like the most important of the eight ASW small-ship classes, the Aux AA ships, the MACs and AMCs and the mixture of ASW aircraft planned? Corvettes and converted merchant vessels do not use Sea Hurricane radiator scoops and are therefore utterly irrelevant to the thread.
Raids would normally include examples like Pearl Harbor, Darwin etc., along with anti shipping, it is the pre war scenario here, the Australians worried about surface raiders with their float planes attacking ships and bombarding, later amended with the idea an IJN force would come with a carrier. The 1939 solution was Sunderland long range reconnaissance, a squadron of Beaufighters as escort and a couple of squadrons of Beauforts with torpedoes, able to detect and strike at ranges longer than the carrier types. The shorter the range of your aircraft the more you need to know where the bad guys are going. Work it out, the carrier could be in home waters and 450 miles from the target, at 25 knots come within range of the target 12 hours, plus any time to raise steam and/or resupply, plus the distance the enemy fleet is beyond the target.
Carriers are rarely used for point defence. A bunch of Beauforts are going to be doing nothing against anything outside a radius of about 550m unless they have more than one field to fly from. In this case, the NW island is under the main threat but the central islands are vital. If you only give your strike wing one airfield, in either of those islands, the other can be smashed by anything around - even Ryujo - and your strike wing will do nothing.
There is no doubt a carrier enhances a naval force, the issue here is how it is being costed.
It's naval force is costed on the official figures from the First Sea Lord, as presented officially to the Parliament of the UK and Australia. I've used the comparison costs given by the RN and RAF for official planning.
The only discussion seems to be about what other costs should be included in a comparison and what other projects to compare the carrier to as a yardstick. I chose EATS because (1) having a much smaller contribution to it financially and in personnel suits "ATLland's" grand strategy; (2) the vast sums that the other SP nations threw at it showed that in the grand scheme of re-armament and war, a light carrier is not a vast cost.
Yes, I was using wartime EATS figures but I don't think it's a gross distortion since if you can afford 40 million pounds in 1939 then you can have afforded 2.8-ish in 1935-1939, when a new carrier would be built.
Because with a range of 150 miles the intelligence/information service needs to be better at warning than for a force with a range of 300 miles to have the strike in range when required. The excellent signals intelligence requires lots of equipment and personnel, that costs. And is the assumption the other side is not as good and therefore cannot track the single good guy carrier with any precision? The Japanese could tell whether Spruance or Halsey were in command and had a good idea when an operation was going to hit, the big unknown was where.
Notice I posed it as a question? It is your scenario. I noted how all land based airfields were charged to to the land based strike force, for costings purposes airfields used by scouting forces could not be used by strike forces.
Simply put from where I sit, you are looking in the mirror when typing the above. Stop loading costs onto one force without also adding them to the other.
To alter things slightly much of the infrastructure to maintain a small air strike force, such as airfields, can already be found in a country that can maintain a small air force, things like training and civil ones for a start. If you are going waive costs for the navy, do so for the air force to keep things even. A 10,000 ton county class cruiser was 640x66, Colossus/Majestic 690x80.25, Hermes 737x90, the larger Illustrious class 766.5x95.75, King George V 745x103. The Australians needed a bigger dry dock for the British Pacific Fleet.
A graving dock as big as the pre-war one in Cockatoo would be large enough for something like a modified Light Fleet or Unicorn. This is not the first large ship the nation has ever owned.