CVA01 and CVV compared

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19 years

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The us CVV concept of the 1970s seems to be quite similar to the RN CVA01 design of the 60s. Any thoughts. They were both roughly 50000 ton 2 catapult 2 lift ships.......

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16 years 3 months

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Almost identical hull sizes, but very different designs.

In a nutshell, CVV seems like a very balanced and capable strike carrier - a modern Midway. Ironically, the USN argued that it was a flawed design. Only compared to a Nimitz class carrier!

IMHO, CVA-01 was well and truly flawed. The RN didn't seem to know what it wanted - an air platform or an escort cruiser (history repeated itself with the Invincibles). It got both, but traded-off capability in too many areas.
- Sea Dart and Ikara installations led to a short, narrow deck, smaller hangar and a huge island. Not so good for aircraft parking and movements. Aircraft capacity was about 45 vs. 60 on CVV.
- The Alaskan taxiway was a way to fix this, but it seems dubious whether this would have worked operationally, especially in heavy weather
- Focus on North Atlantic operations meant CVA-01 couldn't sustain operations for long: only 2,200t of aviation fuel vs. 2,500t-4,000t, range of 6,000nm vs. 8,000nm @20knots

Here's a comparison of the CVA-01, CVV and Midway:

http://i233.photobucket.com/albums/ee106/OPEX-Afghanistan/CVA-01vsCVVvsMidway.jpg

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18 years 3 months

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I have a hunch that if CVA01 had entered service the Ikara and Sea Dart mounts would of been deleted during its mid life refit anyway and the flight deck extended aft.

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16 years 3 months

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I have a hunch that if CVA01 had entered service the Ikara and Sea Dart mounts would of been deleted during its mid life refit anyway and the flight deck extended aft.

Possibly, but unless the flight deck was also widened that wouldn't produce much more deck parking.

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17 years 5 months

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In the early 60s, the RN did know what it wanted, ie a Forrestal/Kitty Hawk type carrier fleet. At the same time it knew it couldn't have them for reasons of size primarily, as they could not be accomodated at either of the RN's Carrier bases (Pompey and Guz), so something smaller had to be accepted. To achieve the desired capability the carrier was split into two ship designs, the CVA would carry the fixed wing strike aircraft and Fleet AEW whilst the smaller 'Escort Cruiser' would operate the ASW helicopters of the Task Group (taking up valuable space aboard the existing carriers thus reducing the numbers of fixed wing aircraft they could carry). The two designs, a 50-60,000 tonne strike carrier and a 12,000 tonne Escort Cruiser, would therefore give the RN the capability of a single much larger carrier design. CVA-01 should not be viewed in isolation from it's companion design (which ultimately evolved into the Invincibles).

The core CVA-01 design was the result of very intense studies of carrier ops with the then new Angled deck carriers, and was the next logical evolution (incorporating the parallell deck concept). The flaws that crept into the design were political in origin, such as the arbitrary tonnage limitation (no larger than Eagle, hence 50,000 tonnes, which crept back up to about 55,000 tonnes in the end anyway), and had the RN and the design team been given a free hand the final layout would be less subject to criticism. The inclusion of Sea Dart at the stern was simply following US practice with the Kitty Hawks (and Enterprise if she had been finished to the original design specs) which were built with two twin Terrier launchers aft. AFAIK, Ikara did not feature in the final design of the CVAs, but four Sea Cat Launchers to supplement the Sea Dart installation are usually quoted, though not specifically shown on official drawings. The reduced flight deck area aft to starboard over the boat deck was probably another weight saving measure, one that would have been rectified soon after entering service.

The Parallell deck layout divided the deck into three separate areas, the landing runway to port, a central deck park alongside the island, and the widened Alaska Higway to starboard of the island, allowing aircraft either from the aft deck park or from the hangar deck brought up on the aft (deck edge) lift to be brought forward to the starboard catapult without interfering with recovery operations or disturbing the deck park. The sponson supporting the Alaska Highway itself was very large and intended to deflect heavy seas from the aircraft movements on the highway. the design has often attracted criticism for not mounting a deck edge lift forward, retaining an inboard lift (of the new 'scissors' design) instead. In fact these features were directly influenced by the operational experience of the RN's carriers in their primary operation areas, eg the Bay of Biscay and the Northern Atlantic. Remember the American Super Carriers were still relatively new and the RN did not have direct experience of operating them or their seaworthiness (in terms of the forward deck edge lifts ant their relative wetness in heavy seas), so the reasoning of the RN is understandable.

The CVV design on the other hand is by definition basically an economy version of the JFK, halved in most of the important details in order to achieve economies. Half the lifts, half the catapults, much reduced steam plant and manning. Ultimately as compromised by the politicians if not more so as CVA-01 was.

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16 years 3 months

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I agree that as originally intended (T-CBL study) CVV was a flawed design. However, by 1978 CVV had evolved significantly into a fully capable strike carrier with a number of improvements (larger aircraft capacity, taller hangar, wider hull, more aviation fuel, better magazine protection, more electronics). The only thing still lacking was speed (26-28kts), which is similar to Charles de Gaulle today and IMHO not a deal breaker. Overall, CVV should have more capable than a Midway, though still far less than a Nimitz CVN.

If the RN had adopted CVV's air group centric approach for CVA-01, it would have ended up with a very powerful carrier, with ~60 Phantoms/Buccaneers instead of only 36, on the same tonnage. That gives an idea of the trade-offs inherent in CVA-01's design.

Regarding CVA, Ikara was indeed deleted from the final CVA-01 design to save weight, but it left its mark by reducing flight deck width and aft deck parking. I don't understand why it was ever included in the first place. Inclusion of Sea Dart is somewhat more understandable in the early 1960s, though Enterprise was sailing around without anything at all at the time and JFK was also being built without the planned Tartars, so by 1964-1965 you could argue that the trend should have been clear enough for the RN to follow suit.

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19 years

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Yes, had those plans gone forward, the RN would have been a truely formidable force.......4 CVAs and however many escort cruisers and type 81s.....funny how witht hte new CVs they RN got the lifts right but messed up the island(2) again. Would the CVV have been able to handle the F-14?

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16 years 3 months

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Yes, CVV was F-14 capable. That's one of the key improvements over the Midways. However, only about 12 F-14s were planned since it was more of a strike carrier. The USN never established a doctrine of use for CVV, so the rest of the air group is unclear. But given its strike focus a and the stated 60-64 aircraft capacity, I would guess:

CVV Airgroup (1980s)
12 F-14
24 A-7 (later 20 F/A-18)
10 A-6
4 KA-6D
4 EA-6B
4 E-2C
6 SH-3
(Basically a normal CV airgroup with one less F-14 squadron and no S-3B Viking squadron)

With a small reduction of air group spot size (5%) to increase sortie rates, that would imply a current air group of about:

CVV Airgroup (2010)
20 F/A-18 E/F
20 F/A-18A/C
4 EA-6B
4 E-2C
6 SH-60

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18 years 10 months

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- The Alaskan taxiway was a way to fix this, but it seems dubious whether this would have worked operationally, especially in heavy weather
- Focus on North Atlantic operations meant CVA-01 couldn't sustain operations for long: only 2,200t of aviation fuel vs. 2,500t-4,000t, range of 6,000nm vs. 8,000nm @20knots

Could I ask, firstly how the Alaskan taxiway would have effected a CVA-01 if we'd had at least one in the Falklands War. And Secondly on the subject of air ops, just what does that break down as in terms of numbers of sorties as well as number of day(s) CVA-01 could have mounted ops for?

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16 years 3 months

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Fin stabilisers were deleted midway through the CVA-01 because of weight constraints (they would have taken up 250t and displaced 550t of fuel), which raises questions about roll behavior. http://books.google.com/books?id=bw46M1qI9gMC&lpg=PA187&ots=WxEnyS4kpf&dq=%22cva-01%22%20%22fin%20stabilisers%22&pg=PA187#v=onepage&q=%22cva-01%22%20%22fin%20stabilisers%22&f=false

(AFAIK CVV, in keeping with USN practice, would not have had fin stabilisers either. She had a 20ft wider deck, but also a 4ft wider waterline beam, so not sure if she would have rolled more or less)

Buccaneers and F-4 Phantoms had 9,000-9,500L of internal + external fuel, so let's say they used 8,100L per mission on average, that rounds nicely to 6.5t. Let's assume 20% of CVA-01's aviation fuel is needed for reserves and the dozen fuel-sipping AEW aircraft and helos, that leaves 1,750t of available aviation fuel.

So CVA-01 could have done around 1,750/6.5 = 275 fighter & strike sorties. Assuming 2 sorties per aircraft per day, that's about 4 days of operations.

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19 years

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If they had gone ahead and had all 3 in service by the end of the 70s.....My opinion is the Falklans war wouldnt have happened.

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15 years 4 months

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Yes, had those plans gone forward, the RN would have been a truely formidable force.......4 CVAs and however many escort cruisers and type 81s.....funny how witht hte new CVs they RN got the lifts right but messed up the island(2) again. Would the CVV have been able to handle the F-14?

Whats wrong with 2 islands. Their properly placed for their respective jobs and are perfect for the gas turbine placement. How would you have placed them and routed the exhausts and air intakes and mounted the radars ect so they don't interfer with each other. Look at how much deck space is taken up on the invincibles doing the same job.

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15 years 9 months

Posts: 1,025

Whats wrong with 2 islands. Their properly placed for their respective jobs and are perfect for the gas turbine placement. How would you have placed them and routed the exhausts and air intakes and mounted the radars ect so they don't interfer with each other. Look at how much deck space is taken up on the invincibles doing the same job.

Yup, I think its quite elegent. Keeps the GT's high up in the hull to minimise the amount of space taken up by piping, plus probably makes them easier to remover and replace.

The two islands allows them to follow the "unit" arrangment with propulsion with the GT's far enough apart that a single hit cannot take out both engine rooms.

Whoever thought that up deserves a drink or two.

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14 years 4 months

Posts: 130

Here's a comparison of the CVA-01, CVV and Midway:
http://i233.photobucket.com/albums/ee106/OPEX-Afghanistan/CVA-01vsCVVvsMidway.jpg

Interesting comparaison
Please, add a top view of the futur british CVF (Queen Elizabeth class), for a better comparaison of actual/older medium carrier

(+ ideally a top view of futur indian IAC, French Charles de Gaulle, Italian Cavour)
;)

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15 years 9 months

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http://www.mod.uk/NR/rdonlyres/584CAAE8-8B39-4271-86E8-86320C7804B7/0/Carrier3_761x437.jpg

How is this for starters?

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14 years 4 months

Posts: 130

How is this for starters?

Yeah ;)

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16 years 3 months

Posts: 630

More carrier porn: :D

http://i233.photobucket.com/albums/ee106/OPEX-Afghanistan/Carriercomparison_smallest.jpg

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16 years 3 months

Posts: 630

It's interesting to note the huge gap in displacement between CVF and all other carriers. I've never understood why it grew so "obese" even though in every respect it's an unremarkable design compared to the much older Midway and CVV... :confused:

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14 years 4 months

Posts: 130

It's interesting to note the huge gap in displacement between CVF and all other carriers. I've never understood why it grew so "obese" even though in every respect it's an unremarkable design compared to the much older Midway and CVV... :confused:

PS: a probable little error
For the CVF, not 74000 tons, but around 64/65600 tons (full loads, start of service life)
Limiting 75,000 tonnes at end of service life (after two re-ballastings)
:D

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16 years 3 months

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PS: a probable little error
For the CVF, not 74000 tons, but around 64/65600 tons (full loads, start of service life)
Limiting 75,000 tonnes at end of service life (after two re-ballastings)
:D

I know. CVF CTOL/PA2 is heavier though: 70,000t start of service life.

I use max displacement intentionally, since most of the other designs were already at their max displacement.

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14 years 4 months

Posts: 130

http://i233.photobucket.com/albums/ee106/OPEX-Afghanistan/Carriercomparison_smallest.jpg

Look that for the US medium aicraft carrier (crew: 4000) & newest british CVF aircraft carrier (crew : 1500), the ratio crew/Displacement/aircraft aboard......is bad for the US medium carrier

Same today for the giant us flatops (nimitz: more than 4500/5000 sailors) :eek: versus around 1500 for french, british, russian carrier :rolleyes:

The futur US carrier needed :rolleyes: to be more automated (with MAJOR crew reduction)