Aircraft Carriers II (Closed to posting)

Obi Wan Russell · Mar 12, 2008

Once upon a time RN carriers were only seen in the Gareloch was when they were laid up awaiting their last voyage to the Breakers yard. Always nice to see an Invincible under way as opposed to tucked away at the back of Portsmouth Naval Base devoid of radar antennae. Still see Invincible every few weeks when work takes me down Pompey way. She is still an impressive sight to behold...

Obi Wan Russell · Mar 19, 2008

I have noticed on another forum the question was raised as to what Italy and Spain would do if the F-35B was cancelled? Assuming the C model went ahead would Cavour be suitable for conversion to CTOL operations? Here's my take on it, a sequence showing what would be involved:

First pic is Cavour as completed; second pic is a step down the CVF route with a wider fight deck 'fitted for but not with' cats and traps; third pic is conversion to ctol and the fourth pic shows further modifications including a shortened island (to avoid fouling the landing area and provide more deck parking space). The cats would be EMALS as it is easier to generate electricity than steam. The loss of compartments in the island is compensated for by the 'Alaska Highway' sponson to starboard which also increases flight deck parking space. If they were to build a second unit of the class (to replace Garibaldi) then this is the route I would advise. The Spanish having gone down the hybrid carrier/LHD route with Juan Carlos I are faced with a tougher challenge as the new ship would b unsuitable for CTOL ops I believe due to low speed mainly. Easier to start from scratch in their case.

harryRIEDL · Mar 19, 2008

Obi Wan Russell said:
I have noticed on another forum the question was raised as to what Italy and Spain would do if the F-35B was cancelled? Assuming the C model went ahead would Cavour be suitable for conversion to CTOL operations? Here's my take on it, a sequence showing what would be involved:

Photos

First pic is Cavour as completed; second pic is a step down the CVF route with a wider fight deck 'fitted for but not with' cats and traps; third pic is conversion to ctol and the fourth pic shows further modifications including a shortened island (to avoid fouling the landing area and provide more deck parking space). The cats would be EMALS as it is easier to generate electricity than steam. The loss of compartments in the island is compensated for by the 'Alaska Highway' sponson to starboard which also increases flight deck parking space. If they were to build a second unit of the class (to replace Garibaldi) then this is the route I would advise. The Spanish having gone down the hybrid carrier/LHD route with Juan Carlos I are faced with a tougher challenge as the new ship would b unsuitable for CTOL ops I believe due to low speed mainly. Easier to start from scratch in their case.

fantastic job Obi wan interesting seeing the change. the changed design has a look of Hermes any idea what the large overhangs would do to the stablitiy to Cavour

Tasman · Mar 19, 2008

harryRIEDL said:
fantastic job Obi wan interesting seeing the change. the changed design has a look of Hermes any idea what the large overhangs would do to the stablitiy to Cavour

I agree that this is a great concept by Obi Wan.

The 'Alaskan Highway' at the side of the island would counter some of the weight of the port extension but draught would increase and stability would certainly be an issue that would have to be dealt with.

Tas

Obi Wan Russell · Mar 19, 2008

The Cavour design has active stabilisers AFAIK, and the overhangs should not be to much of a problem. Older generations of carriers recieved similar upgrades and coped well. The alterations could be easier applied to a second unit of the class (which will likely emerge eventually to replace garibaldi as I said earlier) and may make the design more attractive for export (Brazil, Argentina, Australia, Canada even?). The point was, what are Italy's options if the F-35B fails? In terms of STOVL, it is the only game in town once the Harrier bows out.

Tasman · Mar 20, 2008

Obi Wan Russell said:
The Cavour design has active stabilisers AFAIK, and the overhangs should not be to much of a problem. Older generations of carriers recieved similar upgrades and coped well. The alterations could be easier applied to a second unit of the class (which will likely emerge eventually to replace garibaldi as I said earlier) and may make the design more attractive for export (Brazil, Argentina, Australia, Canada even?). The point was, what are Italy's options if the F-35B fails? In terms of STOVL, it is the only game in town once the Harrier bows out.

A versatile design for a medium sized carrier, able to be adapted for VSTOL or CTOL operations, would certainly be attractive to countries seeking to replace their old CVLs or who might one day want to get back into the carrier business (e.g. Canada, Australia).

I agree that this would be impracticable with an LHD as the low speeds of these vessels would make CTOL ops difficult. This is a worry I have about the Queen Elizabeth design should it eventually need to be configured for CTOL.

Tas

harryRIEDL · Mar 20, 2008

Tasman said:
A versatile design for a medium sized carrier, able to be adapted for VSTOL or CTOL operations, would certainly be attractive to countries seeking to replace their old CVLs or who might one day want to get back into the carrier business (e.g. Canada, Australia).

I agree that this would be impracticable with an LHD as the low speeds of these vessels would make CTOL ops difficult. This is a worry I have about the Queen Elizabeth design should it eventually need to be configured for CTOL.

Tas

well the Darings had a similar speed concern[but were faster than contract speed] the contract speed is meant to be 27kns which should be quick enough for CTOL we will only know when its on sea trials

Obi Wan Russell · Mar 20, 2008

Ctol carriers are ofte quoted as being capable of 30+ knots but in practice this isn't necessary for Launch and recovery most of the time. The Light Fleets sold abroad postwar were only designed for 25 knots and those that recieved Steam catapults could often only make 22-23 knots in their later years. They still managed to operate safely with this speed limitation. More speed is always an advantage, but ship speed isn't the only factor. If the wind over the deck is blowing at 25-30 knots (fairly average for most CV ops) then a carrier only able to make 27-28 knots will not be seriously disadvantaged compared with one that can make 30+ knots as the variation in the wind speed will offset any difference in ship speeds. Quoted speeds for warships should be taken with a pinch of salt anyway, as Invincibles official 28 knot top speed has reportedly been exceeded many times on ops so they are probably in the 30 knot class. CVF will be big enough for lauch ops at lower speeds anyway. The launch capability of a ctol CV is far more dependant on the capacity of it's catapults than the relative size of the deck or speed of the ship. In low wind conditions more power can be fed to the cats to a degree as compensation for a drop in wind over deck (WOD).

Tasman · Mar 20, 2008

Obi Wan Russell said:
Ctol carriers are ofte quoted as being capable of 30+ knots but in practice this isn't necessary for Launch and recovery most of the time. The Light Fleets sold abroad postwar were only designed for 25 knots and those that recieved Steam catapults could often only make 22-23 knots in their later years. They still managed to operate safely with this speed limitation. More speed is always an advantage, but ship speed isn't the only factor. If the wind over the deck is blowing at 25-30 knots (fairly average for most CV ops) then a carrier only able to make 27-28 knots will not be seriously disadvantaged compared with one that can make 30+ knots as the variation in the wind speed will offset any difference in ship speeds. Quoted speeds for warships should be taken with a pinch of salt anyway, as Invincibles official 28 knot top speed has reportedly been exceeded many times on ops so they are probably in the 30 knot class. CVF will be big enough for lauch ops at lower speeds anyway. The launch capability of a ctol CV is far more dependant on the capacity of it's catapults than the relative size of the deck or speed of the ship. In low wind conditions more power can be fed to the cats to a degree as compensation for a drop in wind over deck (WOD).

I'm not sure what the minumum wind over the deck would be for launching (say an F-35C) from the most powerful catapult that can be fitted into a carrier the size of Cavour, but I do know that the old Australian carrier Melbourne, which had a top speed of around 23 knots, struggled to launch her A-4 Skyhawks when wind conditions were light.

At least in the case of the Queen Elizabeths the ships are large enough for the most powerful catapults to be installed.

Tas

bd popeye · Mar 20, 2008

You need about 25-30+ knots of wind to launch an aircraft(F-18) off the deck. As has been pointed out you don't need that much speed from the ship..just the wind speed.

In the MED many times the ship is moving at full speed because the weather is so calm. In the Pacific, Atlantic, North Sea & Baltic much more wind.

I never served on a ship where enough wind speed could not be generated to launch aircraft. Of course all the CVs I served on could exceed 30 knots.

Aircraft Carriers II (Closed to posting)

Obi Wan Russell

Jedi Master

Obi Wan Russell

Jedi Master

harryRIEDL

New Member

Tasman

Junior Member

Obi Wan Russell

Jedi Master

Tasman

Junior Member

harryRIEDL

New Member

Obi Wan Russell

Jedi Master

Tasman

Junior Member

bd popeye

The Last Jedi