Hi All,

During World War II, a fleet carrier had a capacity of approximately 90 aircraft compared to that of an escort carrier with a capacity of approximately 30 aircraft.

For each fleet carrier produced, it seems that the same fighting power could have been achieved with the construction of three escort carriers. Consequently, prior to battle, three escort carriers would have sailed forth for each fleet carrier.

What were the tradeoffs (advantages and disadvantages) of each of these concepts? Please don't just include tactical advantages/disadvantages during battle but include all factors such as cost, time to construct, intimidation factor, manpower requirements, etc.

Thanks in advance,

Bob Guercio

One consideration that strikes me right away is speed. Escort carriers would not need to be fast, since they would only have to keep up with merchant ships. A look at Wikipedia confirms this, with most being capable of less than 20 knots.

By contrast, fleet carriers could be capable of 30 knots (32 for the Essex class). This would be a great advantage tactically, since a fast fleet carrier could choose whether or not to engage slower escort carriers. Also, it would assist in takeoff operations.

However, in the scenario of using escort carriers in all battle conditions, they would have been designed to be fast!

I guess this takes us into the realm of "what was" and "what could have been".

I think we should consider what could have been because you should decide which way to go before you go there and, once decided, you design accordingly.

Bob Guercio

A few quick ones (no doubt others will add more and better argumented things)

1. The speed (already mentioned) but apart from the tactical and strategic disadvantage you also get the fact that escort carriers need more wind to create enough over deck wind for flight operations so are more dependent on the wheater .

2. Protection, barely protection in the escorts.

3. Size = ability to absorb damage

4. No heavy AA (only symbollically one or two guns), especially important when the VT fuse came in use.

5. the only escort carriers that could handle the Hellcat were the Commencement Bay's, but then you are already talking about 18.000 ton ships, so you get only two for an Essex. (so 54 aircraft with all the disadvantages listed)

Escort carriers were very useful in a number of roles and did play the role of fleet carriers a few times when the latter were in short supply.
They could be mass produced on smaller slipways than the fleets. And freed fleet carriers for the front line (but they also ended up in the front line sometimes) And they were an irreplacable part of the fleet that won the atlantic and pacific war.
But they were surely not a replacement and in actual task force not even an addtional asset due to the lack of speed.

Many Greeetings

Aglooka

Norman Freidman in his US warship Design History series, Aircraft Carrier Volume, discusses both the history and rationale for building both escort carriers and fleet carriers. There had been a debate within Navy circles since the inception of aircraft carriers, over whether it was better, considering the limited resources (money mostly), to build a few very large and powerful "flight decks" or to build many smaller, but less capable, "flight decks". There were good theoretical arguments on both sides, but basically, the trade-offs involved cost and time versus efficiency and offensive/defensive power. The US Navy consensus had always favored large heavily armed carriers (usually designated "fleet" carriers) with large airgroups, because ton for ton, these ships were demonstrably more efficient and cost-effective than smaller, cheaper "light" or escort carriers.

However, with the rapid approach of war, it became imperiative to produce as many carrier flight decks as possible in the shortest time possible. Franklin Roosevelt, who often injected himself into technical debates on the relative merits of naval ships, favored the more austere and cheaper ships because these were easier to build quickly, and ship for ship, were cheaper. The USN argued that they might be cheaper, but weren't really that much quicker to build (one Essex clas carrier was launched just 14 months after it's keel was laid) and weren't cost-efficient. They also pointed out that escort carriers, because they were smaller and slower, couldn't operate certain newer aircraft and were easier to sink because passive defensive measures like anti-torpedo bulkheads and extensive compartmentation could not be incorporated in their designs. It was really a form of the old classic question, "how many eggs should you put in one basket"?

Escort carriers however could be converted from merchant ship hulls which did speed their entry into service and, if they were not used in areas of intensive combat, their lack of armament, aircraft operating capabilities, and passive defensive measures wouldn't really matter that much. To give satisfactory service, fleet carriers had to be built from scratch. Although it wasn't always possible to guarantee that escort carriers wouldn't accidently be exposed to heavy attack by enemy forces, it was generally the case that they were not used in the front lines without being protected by regular fleet units. Escort carriers were invaluable for duties such as aircraft ferrying, invasion air support, pilot training, etc. which otherwise would have required the services of fleet carriers, and would have wasted most of the fleet carrier's capabilities.

To make the trade-offs really work to advantage though, one needs enough carriers to fulfill both the separate and different roles of the fleet carriers and the escort carriers. Japan built both Fleet carriers and escort carriers for the same reasons the US did, but the IJN did not find the trade-offs very useful because it didn't have enough of either type and ended up trying to use escort carrer equivalents in the roles of fleet carriers and vice versa. They found out that neither type gave satisfactory service in both roles and ended up being wasteful of resources. Being able to design, build, and properly utilize both fleet and escort carriers does save time and resources, but it is a strategy that only wealthy countries can use.

Yes, but what price in tonnage would that cost ?

greetings

Aglooka

Exactly.

Building fast (25+ knots) escort carriers would have negated most of the inherent advantages of escort carriers. It would make them more expensive, larger, and would increase building time appreciably. In addition, one of the attractions of escort carriers for the US was that they used standard merchant ship propulsion plants which were far easier to build, maintain, and operate, thus reducing costs drastically.

Essentially, a "fast" escort carrier would be what the US Navy termed a "CVL" or Light Fleet Carrier. The USN converted only nine of them from cruiser hulls in 1943, as basically a stop-gap measure for the temporary lack of CV's. They weren't considered as useful in combat as Fleet carriers, or as cheap and easy to build as escort carriers, but they did have the advantage of quickly increasing the number of flight decks which could be used in front line combat.

The question becomes more interesting in my view if we balance the building of fleet carriers against the light fleets as the Brits did. Any opinions on that ?

Aglooka

I thought that a fleet carrier was designed to carry out offensive tasks, and the escort carrier is a defensive tool.

I'm a landlubber so never mind if it seems stupid.

__________________
'We march. The enemy is retreating in transport. We follow on foot.' Lt.Neil McCallum 5/7 Gordons 19th November 1942