WesWorld

I launched a request for information on the carrier board of NavWeaps. Feedback I got could also be interesting for some of you here.

What are the smallest flight decks around on WesWorld?

To the best of my knowledge no CVE had been build yet and for all fleet CV or CVL I assume flight deck is much longer than 400ft. Right?

I guess the Kumano would be less than that...

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Originally posted by HoOmAn
I launched a request for information on the carrier board of NavWeaps. Feedback I got could also be interesting for some of you here.

What are the smallest flight decks around on WesWorld?

To the best of my knowledge no CVE had been build yet and for all fleet CV or CVL I assume flight deck is much longer than 400ft. Right?

To the best of my knowledge, China has the smallest carriers: Zhangyhum, Katar, Aruval, and finally Karkas, all acquired from foreign sources. India's Lathi and Vel are a bit larger. Japan has the Kumano Maru class amphibious assault carriers. All of these ships except Karkas probably would count as CVEs, since they were converted from merchant vessels. (Karkas was converted from a light cruiser.) There are a few more CVEs out there, including Chile's CNS Chiloe, possibly Nordmark's Gärdsmyg, the ex-Peruvian now-Russian Canopus, and maybe a few others.

Edit: Denmark's Jutland is also a small-deck contender.

I think the world record for 'shortest proper flight deck' probably goes to Chile's Guardia Marina Hyatt: it's designed for autogyros and helicopters and not fixed-wing aircraft, though, and doesn't even have arresting gear.

What about the top of Kent Pietsch's RV?

Brock, looking quickly around at the carrier pics, I think (though I could be wrong) that most carriers you mentioned would be at least 400 feet, with exception of the Kumano and Hyatt.

Rough guess on the Hyatt would probably be 260-270 or so. The deck is roughy 60% of the ship's length.

Hmm Link isn't working.

All the Dutch flight decks are more than 400ft, yes.
Hund - 518ft
2x Eendracht - 739ft
Walcheren- 746ft
2x Van Meel - 840ft
Sacre - 747ft

I've thought about this a bit in the past. Hence that thread a bit ago where I was considering what would be needed for a interceptor/recon only platform. If all you have is lightly loaded, high pwr:wt ratio planes, you should be able to get away with a smaller carrier.

I think flight deck length needed is dependent on several variables

1. Wingloading of the planes involved.
Lower wing loadings = takes off and lands at lower speeds and powers, so less deck needed. Jets however took a long time to wind up power, so they needed more space/cat launching.

2. Do you intend to Cat launch planes ? It's far slower. My impression is there were CVEs that seem to have flown off fighters, but cat launched torpedo planes.

3. Do you want to fly off planes up front while recovering aft (inherently more dangerous) - in which case you need more deck length and elevators. If you're willing to sacrifice dual ops, you can probably get away with a shorter deck. Which would seem to be more what the CVEs did.

Never really dug into this too far though....

I did base the Airgroup size on how many fighters one could get airborne in 10-15 minutes after incoming were detected, plus spares.

The last Dutch Carrier Torpedo bomber listed before I quit specifying was designed in 1935 : T-VI, a biplane with a loaded stall speed of 66kts and loaded wing loading of 26lbs/ft - less than many fighters. Granted, I stuck a beast of an engine in it, giving it fighter hp, so it's actually still pretty decent, coming between the Devastator and Avenger in performance.

In my mind, that allow the CV-1 Hund with it's 157m deck and the Eendrachts with their 220m decks to launch torpedo planes.

Note that RykjM had a 156m flight deck and operated A6Ms with a 22lbs/ft wingloading, while HMshM had a 168m flight deck and wiki says :

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HMshM was placed in reserve on 1 December 1937.[28] Her aircraft elevators were enlarged in 1939: the forward elevator to 12.8 by 8.5 meters (42 by 28 ft) and the rear elevator to 13.7 by 7 meters (45 by 23 ft).[29] On 12 August 1939 HMshM was deemed useful as a training carrier and, in critical battles, as a platform for A4N1 (Type 95) fighters and B4Y1 (Type 96) torpedo bombers, for as long as those planes remained serviceable. A later investigation determined on 23 December 1940 that she could not operate the latest aircraft types like the Mitsubishi A6M Zero, the Aichi D3A "Val", or the Nakajima B5N "Kate" in combat.[30] Also, the small size of the carrier's airgroup limited the ship's potential value to the fleet in any future conflicts.[31]

Now, HMshM was used in WWII with the older aircraft.

Then it says :

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In order to service new and larger aircraft like the Nakajima B6N "Jill" torpedo bomber and the Yokosuka D4Y "Judy" dive bomber, the flight deck was extended over 6 meters (19 ft 8 in) at each end to a total length of 180.8 meters (593 ft 2 in) from 27 March to 26 April 1944. HMshM also received new arresting gear and a new crash barrier.

This allowed her to go from flying planes with wingloadings around 15 to closer to 35...and I can't believe a difference 12m is responsible, I'm guessing they sacrificed dual ops or went to Cat Launches, making her a limited carrier that was at least capable of fielding modern aircraft. Considering how badly the IJN needed flight decks at that time, this is a good bet.

I think "Ryujo" and "Hosho" became board casualties...

Good summary. Thanks.

IMHO, from what I understood, everything with at least 150m (492ft) runway does not cause me any headache. Between 140m and 150m limitations have to be accepted regarding type of operation and probably type of aircraft. Things are easier if a catapult is available. Below 140m effective flight operations are seriously limited. Would you agree to this as a rule of thumb?

Of the examples mentioned above that guideline would put the Chinese Zhangyhum at the very edge. He barely makes 140m for her flight deck. It would be less if not for that deck extention aft. What historical design is the based on? She looks a bit like an Empire Mac Rae...

Kumano is clearly below that limit. Her hull is 147m overall but that flight deck barely covers 110m (approx 360ft), according to wiki. With her relatively low speed that is at the very edge of what is required to allow take off at all - not considering biplanes here. Only light-weight a/c like a Zeke may be able to use that deck. However, as an amphibious assault ship she probably just isn't meant to conduct flight operations at all... Walter?

From what I read, only partial flight operations. The idea of the Kumano Maru was to transport fighter planes to various islands. They would be launched from the deck and land on the island. The flightdeck was not intended for recovering aircraft which is why the rear end of the deck is an elevator. (or something like that; it's been a while since I read about it).

Counting pixels, the useable flight deck of the Kumano is roughly 75% of the ship's length (not including the elevator).

According to wiki:

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The ship was also designed to transport anywhere from 8 to 37 aircraft, depending on their size and the number of landing craft aboard. A 110.0 by 21.3 metres (361 by 70 ft) flight deck was mounted above the main deck with an elevator aft. This permitted the stored aircraft to be flown off the ship to onshore airfields. The deck was not large enough to allow aircraft to land. The ship's funnel was mounted on the starboard side and vented horizontally outward to keep the flight deck clear.

There were some historical cases where LSTs received flight decks in order to launch and recover light aircraft like Grasshoppers and Storchs.

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Originally posted by Rooijen10
Rough guess on the Hyatt would probably be 260-270 or so. The deck is roughy 60% of the ship's length.

Probably. I just eyeballed it. The Hyatt is mostly the result of my attempt to convert a lemon into a lime: it's as much an experimental vessel made good than anything else, and she's heavily-flawed. I just can't figure out how to replace that ship yet, and she's got some marginal use in ASW...

Mexico's two CVLs are at 590ft and 557ft. The converted paddlewheeler (hehehe) is at 450ft, but she is primarily a training carrier, although in war would be used for amphibious support flying grasshoppers and A-1s.

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Originally posted by Rooijen10
I think "Ryujo" and "Hosho" became board casualties...

Yeah, to get the proper accents I copied pasted...and then it got chewed up.

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Originally posted by HoOmAn

IMHO, from what I understood, everything with at least 150m (492ft) runway does not cause me any headache. Between 140m and 150m limitations have to be accepted regarding type of operation and probably type of aircraft. Things are easier if a catapult is available. Below 140m effective flight operations are seriously limited. Would you agree to this as a rule of thumb?

Actually, my intepretation is that under 160-170m you're limited to very low wingloading planes for normal operations, the 21lbs/ft A6M seems the heaviest. Japanese practice was to build very light, low wingloading planes which is why they handled so well down low...and shredded under fire. Somewhere over 170-180m you start getting 25-35lbs/ft, which is early war planes. That would also get you into the range of the Independence class CVLs- which were a little small, but did operate TBM Avengers with a 40ish wingloading- but this may (as vague old memory serves) be a Cat-launch plane.

Mid 1940s you saw wingloading in most planes go up as wing area was minimized for speed. So you would expect more deck area to be desirable for that period.
The follow on Saipan class was a bit longer, guessing about 190-200m of deck. Wiki says the British 1942 CVL was designed at 210m. So I'd shoot for that for little/no flight restrictions.

Out of curiosity, I had a look around to see what nation had the carrier with the largest flight deck. The contenders on the basis of overall length:

- Italy, with the Andrea Doria class CVs, has an overall length of 285.56m.
- France, with the Bucentaure class, has an overall length of 285m.
- Russia's Azov class, at an overall length of 276.13m.
- Britain, with the Audacious class, which is 273.11m overall.
- The US fields the 265.06m o/a Ranger and the 259.62m o/a Constellation, while the Essex measures in at 265.71m o/a.
- South Africa, with the incomplete Bahamut, which measures 260.06m overall.
- Japan, with the Shokaku class, has an overall length of 257.71m.; the incomplete Hiyo has an overall length of 276.06m, edging out Audacious.
- The Netherlands, with the van Meel, at 256.06m.
- Germany, with the 251.63m overall Peter Strassers and Scharnhorsts.

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Originally posted by Kaiser Kirk
Actually, my intepretation is that under 160-170m you're limited to very low wingloading planes for normal operations, the 21lbs/ft A6M seems the heaviest. Japanese practice was to build very light, low wingloading planes which is why they handled so well down low...and shredded under fire. Somewhere over 170-180m you start getting 25-35lbs/ft, which is early war planes. That would also get you into the range of the Independence class CVLs- which were a little small, but did operate TBM Avengers with a 40ish wingloading- but this may (as vague old memory serves) be a Cat-launch plane.

What's the wing loading of the Martlet, Hellcat and Avenger? These planes seem to have been successfully operated from British and American CVE. I expect them to have a higher wing load than the Zero.

CVL like the Independance achieved much higher speeds than the usual CVE. Launching planes from a deck 10kn faster is a tad bit easier. Add additional 60ft of flight deck length and you gain the ability to launch strikes of up to 20 a/c from what I understand. I think that's the real difference between CVE and CVL, offering additional operational options, but it is not a matter of type of aircraft.

First, I want to stress that most my warship reading has been focused towards gun vessels. My carrier reading is lighter, and more incidental to the entire war, though I read a nice book on CV-6 once. Visiting Intrepid and Hornet is neat, but not useful for this

Second - to answer your question :
TBF Avenger - 1942 - 36lbs/ft
Hellcat - 1942 - 46lbs/ft max TO , 37lbs/ft "loaded"
Martlet / Wildcat - 1939 - 34lbs/ft max TO , 30lbs/ft "loaded"
Wiki note

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The Wildcat continued to be built throughout the remainder of the war to serve on escort carriers, where larger and heavier fighters could not be used.

TBD Devastator - 1937 - 24lbs/ft max TO

and the P-40 - 35lbs/ft

Why the P-40 ? Because there is a pic I found stating "The first of a pair of USAAF P-40 Warhawks catapults from USS Chenango to explore Port Lyautey runway serviceability in support of the Casablanca landings"

Which goes to my point - if you look at the deck plan of a CVE, You can see the arresting gear runs all the way to forward elevator. From there the Catapult runs to the bow.

My strong impression was that CVEs catapult launched most of their planes, and if the crash barrier is right behind the cat, I doubt they do simultaneous on/off operations.

One of the notes in Wiki* was a high accident rate on Independence due to length.

ed: *actually it must have been on one of the other webpages I browsed trying to look into this issue.

Hence why I opined that there were limits on operations at shorter deck lengths. Indeed, the later escort carriers, like the last class- USS Commencement Bay- were 170m, albeit part of that has to be just the base tanker they were converted from.

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My strong impression was that CVEs catapult launched most of their planes, and if the crash barrier is right behind the cat, I doubt they do simultaneous on/off operations.

I believe that in the period prior to the introduction of angled flight decks, no aircraft carriers would have simultaneously launched and recovered aircraft, catapults or no catapults.

When landed, aircraft were brought forward and parked beyond the crash barriers while landings continued. When aircraft were being launched for a strike, they were all marshaled aft, precluding any sort of landings.

You could be entirely correct Bruce, that's why I started my last post with a disclaimer

The first thing that popped in my head after reading your reply was "No, they can launch CAP off the bow while recovering", but I don't know why. It's possible that sometime in the past quarter century I read of them doing that n some odd situation and it stuck in my head as dual ops

However, even for simple recovery - there's not much space on the bow of Bogue to allow many planes to be parked there.

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Originally posted by Kaiser Kirk
You could be entirely correct Bruce, that's why I started my last post with a disclaimer

The first thing that popped in my head after reading your reply was "No, they can launch CAP off the bow while recovering", but I don't know why. It's possible that sometime in the past quarter century I read of them doing that n some odd situation and it stuck in my head as dual ops

However, even for simple recovery - there's not much space on the bow of Bogue to allow many planes to be parked there.

As someone noted earlier, the tempo of operations for a CVE is far different than a CV or CVL; convoy AS patrols or even CAP would require the launch or recovery of only a small number of aircraft at any one time; even CVEs providing close air support would not be launching deck load strikes. With a relatively slow tempo, it might be able to get aircraft below decks for servicing and not require parking them on the deck.

Bruce is correct in saying simultaneous recovery and launch operations are not something generally done in this period. There might have been a few very rare occasions where doctrine was violated, but they would be pretty extreme aberrations - I don't know of any off the top of my head. Doctrine opposed this since landing accidents were rather more commonplace: if a landing aircraft jumped the wire and the crash barrier, then it could threaten to hit fully-armed and fueled aircraft placed forward, with obviously disastrous consequences. Once the angled deck is a factor, though, a failed recovery simply means the plane either continues flying, or crashes in the sea, with less threat to the ship. There's actually a Wesworld example of this which cogently explains the dangers: when the Nordish carrier suffered her big accident and fire, the French and the Chileans just had to shake their heads in dismay. The Nordish were recovering fighters at the same time they were warming up a strike. I guess the French reaction was, well... "What do you expect to happen when you do that? We thought you guys were professionals! What were you thinking?" (Answer: "Clearly, we were thinking we would get away with it...")

This difficulty with managing launch and recovery operations is what happened to the Japanese at Midway. The irregular attacks by small American squadrons forced the carriers to conduct very short spot-launch-clear-recover cycles. Returning strike aircraft and CAP fighters were recovered and launched, recovered and launched - all the while delaying the Japanese from spotting and launching their next large strike of the day. While they had very quick turnaround times between launch of CAP fighters and recovery of aircraft (the mark of a veteran deck crew), they were constantly constrained in how many plans they could actually spot. (The Japanese also had some difficulty due to Kaga's design - with her length and a speed of only twenty-six knots, she could not launch loaded torpedo planes from the front rank of a parked strike: they could not achieve sufficient takeoff roll.)

Back when I wrote the big ABC carrier-centric exercise - think it was 1941 or so - I tried to show just how difficult it is for a carrier crew and their task force commander to get the tempo of operations down just right. When Libertad sent up her airgroup, she launched her planes at a rate of one every sixty seconds - a sterling performance from a well-drilled crew. Even with this rapid launch sequence, it took Libertad up to forty minutes to launch a strike. (That required the lead planes to circle the carrier for forty minutes, waiting as the rest of their squadron-mates launched and formed up.) In several situations, one or more of the carriers set up half-strikes, launched them quickly, and then hurriedly spotted and launched another half-strike - usually with severely decreased striking power.

Another interesting thread. It's been a long time since we've had such technical discussions!

Brock's last post was very interesting. I can't help but think of Hoo's comments in the Indian Ships thread about carriers and their importance and value compared to capital ships. It's clear that even the biggest fleet carriers have limitations in deck operations and launch cycles. Fleet carriers have got much bigger to increase deckspace and stow increasing numbers of larger and heavier aircraft. We are probably reaching the limits of what can be done. The Audacious is effectively the OTL Malta class and it was at the very limit of the slipway and dry dock capacity in Britain (about three drydocks if I remember correctly, most of the them civilian). Here its 4-5th place in size. Of course in WW all slips and docks are treated as equal in terms of size, width and basin depth, but in reality most slips and docks have limiting factors with deck overhangs and approaches etc. Was there any historical slip/ drydock that could have accommodated the Andrea Doria in Italy OTL? I think this shows the limitations begin faced to get an effective airgroup afloat, but as Brock says even launching 40-60 aircraft takes the best part of an hour or more. That's eating into strike sortie range, not to mention another hour or more before all are landed again. Partial angled decks have been introduced waaaay early and probably have alleviated some issues. Britain is working on a steam catapult but that more to do with increasing weights than speeding up the launching process and its not even gone to sea yet. The steam requirements and effect on launching speed isn't known yet and how many WW carriers could be refitted without new boilers? Much to ponder methinks.