WesWorld

The Russian Federaion Navy has reserved 4 8000-ton colliers for conversion to CVEs in the event a war is seen approaching. They will carry 20-24 aircraft, and some novel concepts are being explored. One of them is the use of twin catapults located near twin elevators to get aircraft into the air more rapidly:





How does she look?

The design would have ~800 tons of mics weight - 600 for 24 aircraft, and 200 for the extra fittings.

What year is she planned to be built in roughly? In the 20 the "En Vouge" thing was flying off decks and I'm not sure how popular or available catapults were in the early 20's. Perhaps I could draw one up for you.

The design year is 1928, or thereabouts.

While I like your idea (those twin catapults are cool) I have to question the daet of 1928 for CVEs from a historical point of view.

(You expected that, I guess?! :o))

Regards,

HoOmAn

The four colliers are reserved for conversion when war is seen to approach. The specific design depends on the year that happens. I imagine that if there had been a naval war with subs and commerce-raiding in our world in 1928, something similar might have been put together. So think of it as a wartime expedient, and not something intended for a specific year. And below is my 4-catapult design

This way, I figure I can store 4 aircraft on the catapults, four aircraft on deck, and sixteen in the hangar.

Sounds suspiciously similar to the little Otta...

Would the cats actually be quicker? Seems to me you'd spend as much time putting them on the catapults as you would just doing a running take-off.

I don't know about use as an ASW platform that early, but could see the group being considered as an emergency CAP/scouting platform for the battleline. Depends on what Russian naval aviation experiments determine, I guess.

By the way - I'm glad to see some folks sticking scale bars into their pics...

The drawing seems to need a lot higher hangar. 2 lifts don't seem very realistic on such a small vessel. As for a 8000t ship carrying 24 planes. that isn't realistic. The first CVEs in WWII were of ~15,000t and carried 15 planes i think.

Most interesting - it seems as if some of the pieces on my template found their way onto the Admirals drawings.... ;o) Cranes, catapults and guns... I seem to remember them all. Glad somebody could use them...

HoOmAn

Perhaps you need to start collecting royalties...

That´s a good idea...

0,1pts of infrastructure points per quarter doesn´t seem too much, does it? ;o)

I think it's really quite generous. Now who was it that had cut and pasted my little biplane...?

A saint? You wont really raise an eyebrow because of a member of that group, eh? SAINTs could be just too important for your own policy.....

;o)

No, I wouldn't raise an eyebrow...especially as I might soon be borrowing some pieces off your template...

Quoted

As for a 8000t ship carrying 24 planes. that isn't realistic. The first CVEs in WWII were of ~15,000t and carried 15 planes i think.

A quick google showed several CEs of about 8000 tons Standard. Full load displacement was about 14,000 tons.

But part of why I'm considering catapults is to allow on-deck storage of aircraft while still permitting aircraft to be launched and recovered. On the four-catapult design, four can go in the catapults and four on the deck, leaving 16 for me to find room for in the hangar.

Sounds like we will soon have a new business in the sim.......trading template parts for infrastructure points!!

Again, 1928 is only an example. The actual date depends on the course of world events.

And yes, the armored deck is entirely superfluous, but I had to think of <something> to do with all that hull strength!

Escort Carrier, converted 1928

Length, 140.0 m x Beam, 20.0 m x Depth, 5.0 m
7763 tonnes normal displacement (6387 tonnes standard)

Main battery: 2 x 13.0-cm (1 x 2)
Secondary battery: 4 x 7.5-cm
AA battery: 12 x 3.7-cm

Weight of broadside: 93 kg

Armor deck, average 7.5 cm

Battery armor:
Main, 2.5 cm / secondary, 2.5 cm shields
AA, 2.5 cm shields


Aircraft - 24 (8 Fighter, 8 TB, 8 Recce), 4 Catapults, 4 Cranes
plus an extra 200 tons of aviation fuel and munitions

Maximum speed for 10051 shaft kw = 20.00 knots
Approximate cruising radius, 20000 nm / 12 knots

Typical complement: 414-538


Estimated cost, $4.546 million (£1.137 million)

Remarks:

Ship has slow, easy roll; a good, steady gun platform.

Excellent seaboat; comfortable and able to fight her guns
in the heaviest weather.

Magazines and engineering spaces are roomy, with superior
watertight subdivision.

Ship is roomy, with superior accommodation and working space.


Distribution of weights:
Percent
normal
displacement:

Armament ......................... 26 tonnes = 0 pct
Armor, total ..................... 1125 tonnes = 14 pct

Deck 1102 tonnes = 14 pct
Armament 22 tonnes = 0 pct

Machinery ........................ 419 tonnes = 5 pct
Hull and fittings; equipment ..... 3645 tonnes = 47 pct
Fuel, ammunition, stores ......... 1548 tonnes = 20 pct
Miscellaneous weights ............ 1000 tonnes = 13 pct
-----
7763 tonnes = 100 pct

Estimated metacentric height, 1.3 m

Displacement summary:

Light ship: 6215 tonnes
Standard displacement: 6387 tonnes
Normal service: 7763 tonnes
Full load: 8833 tonnes

Loading submergence 1891 tonnes/metre

+++++++++++++++++++++++++


Estimated overall survivability and seakeeping ability:

Relative margin of stability: 1.33

Shellfire needed to sink: 12691 kg = 416.0 x 13.0-cm shells
(Approximates weight of penetrating
shell hits needed to sink ship,
not counting critical hits)

Torpedoes needed to sink: 5.3
(Approximates number of 'typical'
torpedo hits needed to sink ship)

Relative steadiness as gun platform, 71 percent
(50 percent is 'average')

Relative rocking effect from firing to beam, 0.03

Relative quality as a seaboat: 1.68

+++++++++++++++++++++++++


Hull form characteristics:

Block coefficient: 0.55
Sharpness coefficient: 0.39
Hull speed coefficient 'M' = 7.09
'Natural speed' for length = 21.4 knots
Power going to wave formation
at top speed: 43 percent


Estimated hull characteristics and strength:

Relative underwater volume absorbed by
magazines and engineering spaces: 36 percent

Relative accommodation and working space: 152 percent


Displacement factor: 245 percent
(Displacement relative to loading factors)


Relative cross-sectional hull strength: 1.55
(Structure weight per square
metre of hull surface: 619 kg)

Relative longitudinal hull strength: 2.03
(for 5.00 m average freeboard;
freeboard adjustment +0.61 m)

Relative composite hull strength: 1.59

+++++++++++++++++++++++++


[Machine-readable parameters: Spring Style v. 1.2.1]

459.20 x 65.60 x 16.40; 16.40 -- Dimensions
0.55 -- Block coefficient
1928 -- Year laid down
20.00 / 20000 / 12.00; Oil-fired turbine or equivalent -- Speed / radius / cruise
1000 tons -- Miscellaneous weights
++++++++++
2 x 5.12; 1 -- Main battery; turrets
Central positioning of guns
:
4 x 2.95; 0 -- Secondary battery; turrets
Gun-shields
:
12 x 1.46 -- Tertiary (QF/AA) battery
Gun-shields
:
0 -- No fourth (light) battery
0 -- No torpedo armament
++++++++++
0.00 -- No belt armor
2.95 / 0.00 -- Deck / CT
0.98 / 0.98 / 0.98 / 0.00 -- Battery armor


(Note: For portability, values are stored in Anglo-American units)


+++++++++++++++++++++++++++++++++++++++++++++++++++++++