Conversion of V/STOL aircraft-carriers for CAT/STOBAR operations ?

I still hope one day that an AEW Osprey gets developed at some point.
the Osprey is already starting to replace the C-2 for cargo
Wedgetail Osprey!

Yes, I know that the Wedgetail radar is probably way too heavy to stick into an Osprey. What other options are out there for a surveillance radar type fit in, say, 8klbs?

And while we're at it, someone fund the SV-22 MPA Osprey, please!


Thank you!


The difference in wingspan is 8ft (2.5m), but since only the right wing matters from a clearance perspective, the Hawkeye’s impact on the foul deck line is only 4ft (1.25m)… really not that significant.

That’s not the real issue preventing simultaneous launch & recovery, which has more to do with positioning the bow catapult in a way that maximizes flight deck parking. And also as aircraft get heavier this requires longer catapults and longer landing areas (75m cats and 200m angle deck on CdG for example), making it almost impossible to keep the 2 from overlapping on a small/medium carrier with a max flight deck length of ~250m.
So shifting the bow cat half the width of the JBD may leave the Hawkeye and COD/tankers clear of the foul line, then. Depends on what the required clearances are of the line, I guess.



When was that proposed? Did it reach production? How would that stack up against an E-2C as it entered French service in 2000?
Looking at how small an antenna it is compared to Tracer and Hawkeye, I'm suspicious of the range.

Edit: entered service in the 1990s according to Wiki.
 
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France thought of buying E-1B Tracer at both ends of the Clemenceau carriers lives: 1963 and 1988. Interestingly enough the book mentions "they would have needed turboprops ". And the 1989-92 magazines says "Just like the Sécurité Civile TurboTrackers."

So - it could have happened.
If they would have bought the Tracers in 1963 it would have been better.

First order of business would be new engines, to avoid a mixed AvGas/Jet A supply onboard ship. Turbines won't complain too much about AvGas, but pistons won't run on Jet A. Garrett TPE331s or Lycoming T55s are the likely options in the 1960s from the US market, not sure what engines were available in Europe in the 1500hp power range then.

Later on you can install a better radar, maybe even that of the Hawkeye if the radome is big enough.
 
Wedgetail Osprey!

Yes, I know that the Wedgetail radar is probably way too heavy to stick into an Osprey. What other options are out there for a surveillance radar type fit in, say, 8klbs?
Per wiki, the Wedgetail radar antenna alone is 3.5 tons, and I'd bet good money that the computers and displays to run the radar weigh more than 1000lbs, and 8x crew at 250lbs each is 2000lbs. But Ospreys can carry 20,000lbs internally not 10klbs, so there's enough weight capacity for a Wedgetail radar in an Osprey, I think.
 
Garrett TPE331s or Lycoming T55s are the likely options in the 1960s from the US market, not sure what engines were available in Europe in the 1500hp power range then.
RR Dart or AS Mamba would both work very nicely.

Both were used for DC-3 turboprop conversions and the Dart (RDA.6) was also used for the Grumman/Conway Turbo Albatross which is related to the Tracker and used the same piston engine. As a bonus they were also both navalized (Dart on Breguet Alizé and Mamba on Short Seamew and Fairey Gannet).
 
When was that proposed? Did it reach production? How would that stack up against an E-2C as it entered French service in 2000?
https://www.naval.com.br/blog/2010/08/12/marinha-adquire-08-aeronaves-c-1a-trader/
https://www.naval.com.br/blog/2009/08/01/atualizacao-na-aviacao-naval/
C-1A-Trader-termo-aditivo-contrato-moderniza%C3%A7%C3%A3o-1-960x636.jpg

https://www.naval.com.br/blog/2014/...trato-de-modernizacao-dos-avioes-c-1a-trader/
 
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The Tracker AEW idea was dropped early on and the Brazilian program continued with only 6 Traders (4 for COD and 2 for refueling).

After numerous delays and spending money for 10 years the program was eventually put out of its misery with nothing to show for… not a single aircraft flew. A complete waste of resources (especially since recovery tanking could have been done by A-4 Skyhawk buddy tankers).
 
The Tracker AEW idea was dropped early on and the Brazilian program continued with only 6 Traders (4 for COD and 2 for refueling).

After numerous delays and spending money for 10 years the program was eventually put out of its misery with nothing to show for… not a single aircraft flew. A complete waste of resources (especially since recovery tanking could have been done by A-4 Skyhawk buddy tankers).
Yes....
 
So we return to the notion that the S-2 Tracker was not an AEW aircraft.
Which systems were the Brazilian AEW Trackers to be equipped with?
 
@F.L. That angle deck is too big… would not be manageable from a seakeeping / stability perspective.

Back in the day I drew up a Principe de Asturias-sized CATOBAR carrier based on Bazan’s SAC 200/220 designs, but shrunk to 185 meters. It was as small as I dared make it! But that would have been a new build, not a conversion.

BSAC-185
22,000t CTOL carrier with 20 Sea Gripen, 3 Alize AEW & 4-5 helos
BSAC_185.jpg


BSAC_185_&_220.jpg
I really like the 185 concept, but personally i wouldn't see such a small island on a non-nuclear carrier, an alternative would be to make a twin island design like the QE, with the structure ahead of the forward elevator.
Another thing that puzzles me is with the elevators seem to end up a little too inward, preventing the hangar doors from being closed.
Lastly the hull shape seems to be longer than the flight deck, so maybe it should be reworked a little.
Only some (hopefully) constructive criticism, let me know if you have any questions.
Also what program did you use for your drawings? I'd really like to try my hand at it.
Thank you.
 
what program did you use for your drawings? I'd really like to try my hand at it.
Paint.net on PC is a great drawing tool - it’s free, easy to use, and allows simple layers. Unfortunately now I use a Mac and have never found a great replacement.

That was a rough drawing and certainly not perfect. I would probably do it slightly differently today, with more knowledge and experience. The island size was based on some SCS/VSS sketch drawings I believe… the simple propulsion arrangement with 2 LM2500 gas turbines allowed the island to be very compact.
 
Paint.net on PC is a great drawing tool - it’s free, easy to use, and allows simple layers. Unfortunately now I use a Mac and have never found a great replacement.

That was a rough drawing and certainly not perfect. I would probably do it slightly differently today, with more knowledge and experience. The island size was based on some SCS/VSS sketch drawings I believe… the simple propulsion arrangement with 2 LM2500 gas turbines allowed the island to be very compact.
I loved the Bazan Small Aircraft Carrier designs and I drew the designs auf BSAC 220 following an artists impression from Bazan which showed the island which look to me an Island of Principe de Asturias. I am scanning the internet since these years for the BSAC220 and 240 but always find the same drawings - one day I would love to find cutaways or deck plans but I am afraid they don't exist ;-)
 
Paint.net on PC is a great drawing tool - it’s free, easy to use, and allows simple layers. Unfortunately now I use a Mac and have never found a great replacement.

That was a rough drawing and certainly not perfect. I would probably do it slightly differently today, with more knowledge and experience. The island size was based on some SCS/VSS sketch drawings I believe… the simple propulsion arrangement with 2 LM2500 gas turbines allowed the island to be very compact.
You know i'd really like to see a catobar Cavor, something similar to this
 

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Hrm. Looks like it'd be possible to fit the E2 radar onto an E1 (or S2) airframe, there's enough space between the wing folds that the radome should clear the wings when folded.

The electronics of the E-2 are so much larger than the E-1 airframe could hold. Otherwise they wouldn't have made a new airframe.

What other options are out there for a surveillance radar type fit in, say, 8klbs?

Erieye, probably. The arrays are just under a ton and the whole system fits in a Saab 340B (payload around 8500lbs) The geometry is not kind, though; if you try to top-mount the array, it has to counter-rotate while the wing stows and you have to run a lolt of stuff though the pivot (wiring, cooling, etc). And there's no clearance to put the array under an Osprey. Best bet is to split the array lengthwise and scab it onto the sides of the sponsons.

Erieye also has the drawback of having no endfire arrays, so it only sees 120-150 degrees either side of the midline (sources vary). There are >30-degree dead zones fore and aft, which is fine if you are flying racetracks behind a reasonably straight border but sucks for war-at-sea scenarios where 360-degree coverage is needed.

Osprey itself has another problem. It's not pressurized, so the crew is on oxygen for any sustained flight over 10k feet. AEW wants more altitude than that; the E-2D mission is typically flown above 25k feet.
 
Osprey itself has another problem. It's not pressurized, so the crew is on oxygen for any sustained flight over 10k feet. AEW wants more altitude than that; the E-2D mission is typically flown above 25k feet.
Bugger. That throws a large wrench in the plans.

Unless the AW809 can play?
 
Hello guys… I know I’m quite late to the discussion, but I’ve drawn this concept up on my phone… And yea, since its on my phone only, the dimensions might have some inaccuracies here and there, but hey, this is just purely hypothetical concept and therefore just a visual representation of what it would look like beside the French carrier Charles de Gaulle and the conceptual Bazan SAC-220 that was proposed to Argentina and China back in the 90s…

The reason for me adding this here is because as stated in the earliest discussions in this thread, one main problem with smaller CATOBAR/STOBAR carriers is that they’re not wide enough… So I’m wondering what would you guys think about this very very hypothetical concept, would it be feasible to construct a short yet comparatively wider carrier? How would it affect the stability or mobility of the ship?



Light Fleet Carrier Concept for the Indian and/or Brazilian Navies

Length: 220.5 meters
Tonnage: 32,000 tons
Carrier Type: CATOBAR
Equipped with 3 steam catapults, each 75 meters in length, and 2 aircraft lifts

Propulsion: Combined Diesel-Electric and Gas (CODLAG) or Combined Gas and Gas (COGAG)

Possible Armament:
4x Gun-based CIWS (Phalanx/Goalkeeper/AK-630/others)

2x Missile-based SHORAD
(RIM-116 RAM/Mistral Sadral/others)

1x 127mm Main Gun
(Otobreda 127 or Naval gun Mk45)

1x 16-cell VLS (Sylver or Mk41)


Complement:
Can carry a mix of 35 aircraft comprising:

20x Light Multirole Fighter Jets
(Gripen M or Tejas N, or a mix of both)

6x Electronic Warfare Attack Aircraft
(E/A-18G Growler or other similar aircraft)

2x AWACS / AEW&C
(E-2C/D Hawkeye or other similar aircraft)

7x Helicopters (mix of Seahawks and Ospreys, or other comparable helicopters)


Note: the Indian/Brazilian part is just for added realism purposes, given that among the regional powers, these two are the ones most likely to benefit from such a concept should they wish to have it (Brazil’s Embraer is a partner manufacturer of SAAB for the JAS-39 Gripen E/F, and if they wish, they could fund the development of the Gripen M, and India has their own single-engine light fighter prototype capable of carrier operations, which is the HAL Tejas N)
 

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Hello guys… I know I’m quite late to the discussion, but I’ve drawn this concept up on my phone… And yea, since its on my phone only, the dimensions might have some inaccuracies here and there, but hey, this is just purely hypothetical concept and therefore just a visual representation of what it would look like beside the French carrier Charles de Gaulle and the conceptual Bazan SAC-220 that was proposed to Argentina and China back in the 90s…

The reason for me adding this here is because as stated in the earliest discussions in this thread, one main problem with smaller CATOBAR/STOBAR carriers is that they’re not wide enough… So I’m wondering what would you guys think about this very very hypothetical concept, would it be feasible to construct a short yet comparatively wider carrier? How would it affect the stability or mobility of the ship?
Well, one major issue is that you get into L/B ratio problems. Bad L/B ratio increases how much horsepower it takes to go a certain speed.

A second issue is landing length. You need a certain minimum distance to catch a plane, based on the max-recovery weight pull-out on the last wire.



Light Fleet Carrier Concept for the Indian and/or Brazilian Navies

Length: 220.5 meters
Tonnage: 32,000 tons
Carrier Type: CATOBAR
Equipped with 3 steam catapults, each 75 meters in length, and 2 aircraft lifts

Propulsion: Combined Diesel-Electric and Gas (CODLAG) or Combined Gas and Gas (COGAG)

Possible Armament:
4x Gun-based CIWS (Phalanx/Goalkeeper/AK-630/others)

2x Missile-based SHORAD
(RIM-116 RAM/Mistral Sadral/others)

1x 127mm Main Gun
(Otobreda 127 or Naval gun Mk45)

1x 16-cell VLS (Sylver or Mk41)


Complement:
Can carry a mix of 35 aircraft comprising:

20x Light Multirole Fighter Jets
(Gripen M or Tejas N, or a mix of both)

6x Electronic Warfare Attack Aircraft
(E/A-18G Growler or other similar aircraft)

2x AWACS / AEW&C
(E-2C/D Hawkeye or other similar aircraft)

7x Helicopters (mix of Seahawks and Ospreys, or other comparable helicopters)


Note: the Indian/Brazilian part is just for added realism purposes, given that among the regional powers, these two are the ones most likely to benefit from such a concept should they wish to have it (Brazil’s Embraer is a partner manufacturer of SAAB for the JAS-39 Gripen E/F, and if they wish, they could fund the development of the Gripen M, and India has their own single-engine light fighter prototype capable of carrier operations, which is the HAL Tejas N)
Why is there a 5" gun on a carrier?
 
Well, one major issue is that you get into L/B ratio problems. Bad L/B ratio increases how much horsepower it takes to go a certain speed.
So in theory, wouldn’t the QE-class be suffering from this issue too, considering that it is comparable to the Charles de Gaulle in length, but its beam is comparable to those of USN supercarriers?

A second issue is landing length. You need a certain minimum distance to catch a plane, based on the max-recovery weight pull-out on the last wire.
I don’t think it’s going to be much of an issue for this specific concept… If you look at it, its landing strip length is not that significantly shorter compared to the Charles de Gaulle so I don’t think it matters that much, considering that landing accident rates in the Charles de Gaulle is not high… And besides, we have to take note especially of the Gripen’s STOL capabilities, which I believe would come in handy in this situation.

Why is there a 5" gun on a carrier?
Well, the Italian carrier Cavour has an Oto 76mm gun on it am I right? Or was it the Garibaldi? Either way, I don’t think its much of a stretch to add a naval gun on a carrier… Its sort of for last defense mechanism when all of its missiles and aircraft are gone (hypothetically), and it comes within firing range of its opposing vessels… Orr it could be used for shore bombardments (?) if it is to be used as something like an LHD… (Afaik, the QE-class has some limited amphibious capability, am I right?)

Either way, its not rlly much of a problem… The gun can be removed if necessary… It’s just that I think this ship is wide enough to have extra space for a naval gun and its related systems and ammunition soo I added it just to somehow demonstrate…
 
So in theory, wouldn’t the QE-class be suffering from this issue too, considering that it is comparable to the Charles de Gaulle in length, but its beam is comparable to those of USN supercarriers?
Yes.


I don’t think it’s going to be much of an issue for this specific concept… If you look at it, its landing strip length is not that significantly shorter compared to the Charles de Gaulle so I don’t think it matters that much, considering that landing accident rates in the Charles de Gaulle is not high… And besides, we have to take note especially of the Gripen’s STOL capabilities, which I believe would come in handy in this situation.
A few meters is all it takes. I believe the limiting aircraft is the E-2, as it's the longest from nose gear to tailhook.



Well, the Italian carrier Cavour has an Oto 76mm gun on it am I right? Or was it the Garibaldi? Either way, I don’t think its much of a stretch to add a naval gun on a carrier… Its sort of for last defense mechanism when all of its missiles and aircraft are gone (hypothetically), and it comes within firing range of its opposing vessels… Orr it could be used for shore bombardments (?) if it is to be used as something like an LHD… (Afaik, the QE-class has some limited amphibious capability, am I right?)
The Oto 76mm is basically a point-defense gun as far as the Italians are concerned. They treat it the same as the Phalanx CIWS.
 
Yes.



A few meters is all it takes. I believe the limiting aircraft is the E-2, as it's the longest from nose gear to tailhook.




The Oto 76mm is basically a point-defense gun as far as the Italians are concerned. They treat it the same as the Phalanx CIWS.
Soo with all this taken into account, bar some minor modifications to its length, you think the concept is still feasible right?

And as far as the bad L/B ratio is concerned, with an extremely powerful integrated propulsion like those found in the QE-class, it wouldn’t be much of a problem?

And as for the naval gun, would removing it be much more of a benefit than having it? (less contingency, but extra added space?)

Also, what do you think of CODLAG as propulsion system? Would it work or be feasible with this concept, or better stick with COGAG? Would a future upgrade to IEP be feasible?
 
Soo with all this taken into account, bar some minor modifications to its length, you think the concept is still feasible right?
With careful design, a cat/STOBAR carrier roughly 45,000 tons (Midway sized) is viable with modern aircraft sizes. I think you're going to struggle having a long enough angled flight deck or hangar space with anything less.

Remember how many airframes you need just for carrier support.
8-12 aircraft for CAP
3-5 AEW if fixed-wing, 5-7 if helicopter
~8 ASW helos (also includes plane guard, having 3-5 others dedicated would be better)
2-3 COD airframes

Then you can add the planes for the carrier's actual mission. Strike planes, more ASW coverage, whatever.




And as far as the bad L/B ratio is concerned, with an extremely powerful integrated propulsion like those found in the QE-class, it wouldn’t be much of a problem?
Still means you need a lot of horsepower on the shafts, which costs fuel.
Example: the 1939 South Dakota class BBs versus their predecessors the North Carolina class. SoDaks needed 130khp for 27.5 knots, while NoCars had 121khp for 28 knots. Also, the SoDaks would only cover 15,000nmi at 15 knots, while the NoCars would cover 17,450nmi at 15 knots.



And as for the naval gun, would removing it be much more of a benefit than having it? (less contingency, but extra added space?)
I mean, if you had OTO 76mm instead of Phalanx it'd be a reasonable trade. If it's the Sovraponte (decktop mount), it actually weighs about as much as the full Phalanx mount!



Also, what do you think of CODLAG as propulsion system? Would it work or be feasible with this concept, or better stick with COGAG? Would a future upgrade to IEP be feasible?
I'd go straight to IEP and/or COGAS. COGAS is sneaky because it extracts heat from the GT exhaust to boil water and spin turbines to make electricity. Greatly reduces your ship's IR signature.
 
The Oto 76mm is basically a point-defense gun as far as the Italians are concerned. They treat it the same as the Phalanx CIWS.
It's programmable rounds, combined with the weight of the rounds is very effective! Keeping in mind its a DP gun mount, so it's effectiveness against small attack craft should also be appreciated.
I guess another reality lost in the West with obsession with everything missiles....

Regards
Pioneer
 
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It's programmable rounds, combined with the weight of the rounds is very effective! Keeping in mind its a DP gun mount, so it's effectiveness against small attack craft should also be appreciated.
I guess another reality lost in the West with obsession with everything missiles....

Regards
Pioneer
yes I believe larger-caliber guns with less rate of fire for CIWS is the new trend, combined with programmable/proximity fuse/airburst munitions like the German AHEAD round (30-35mm) or the Turkish ATOM round (35mm), or the Italian Strales (76mm) and Vulcano (127mm) rounds… I believe that with the advent of smaller, faster, and more maneuverable smart missiles, having the capability to shoot them down as far out as possible would be most beneficial, as opposed to extremely-close-ranged but high rate of fire point defense like the gatling-gun type CIWS such as the Phalanx or Goalkeeper… I believe these gatling-style CIWS are obsolete, because again, faster smart missiles can counter these things very effectively despite their high rate of fire, through unpredictable maneuvers… That’s why even the USN is slowly replacing the Phalanx either with the RIM-116 or the SeaRAM, which are missile-based CIWS… Of course, I do agree that not everything should be left to missiles, as they too have many limitations that “guns and bullets” dont have… Their mostly only upper side is their range, other than that, I think modern gun rounds are better than them in almost every other parameter other than range…
 
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