075 LHD thread

[plawolf]

Bringing the discussion back to possible future PLAN LHDs, how feasible would it be to add a removeable ski jump (like the US marines desperately wanted to with their Wasp class) with space left for catapults upgrades at a later date like the British were supposed to have done with their EQII class and maybe add in an angled deck to make it a pocket carrier?

All of that would be primarily deck work that would not much impact on the internals of the ship so seems like something that should be fairly easy to design into a LHD or even retrofit into an existing design. This would allow the LHD to conduct fixed wing operations to an extent without needing VTOL jets.

Owing to the smaller size of an LHD, the angled deck would need to share a far larger part of the deck than a traditional carrier, so simultaneous take offs and landings may not be possible, and the large size of the J15 would make it a poor fit for such a pocket carrier in any case. But I think such a ship should be able to take a decent complement of L15 or JL9 based attack aircraft for CAS duties, which would be the main mission a VTOL jet would perform in such a scenario anyways.

 

[Blitzo]

While I think embarking a small wing of navalized JL-15s is interesting, the cost of modifying and building an LHD for those purposes, along with the potential difficulties in training a crew, pilots, etc, is not worthwhile, because the PLAMC is not as independent from the navy as the USMC is from the USN, and an LHD in an operation where PLA landing forces require air support will have a carrier to assist, which could do far more than the relatively meager complement of a JL-15 on a 40k ton LHD.

Personally I'd prefer to see the PLAN invest in more advanced helicopters, whether its tilt rotor or high speed coaxial/pusher prop, which can do similar speeds to fixed wing turboprop aircraft with the benefits of being a vertical take off and landing helicopter.
Let PLAN CVs and CVNs shoulder the need for CAS and strike. Let LHDs act primarily as amphibious assault ships and helicopter carriers.

 

[delft]

Just depends on what their requirements are.

Getting a decent STOL aircraft with good ground support, fighter, and in excess of Mach 1 is pretty much impossible for your normal STOL aircraft. That's whay the Harrier came alon, why the Russins were designing the Yak-141, and the US is producing the F-35B.

If the PLAN has those requirements, then a jet fighter like the Yak-141 or the F-35B is the answer.

If they want an aircraft like the OV-10A, then that could easily fly off of an LHA without the VTOL/Jet component.

Harrier was developed to provide air support when conventional airfields were considered too vulnerable to depend on. As such they were really a failure but when then RN couldn't replace its flattops with similar ships due to financial constraints the through deck cruiser was invented to make use of the available Harrier. The ski ramp was invented no later than 1948 when Arthur C. Clarke used it in a novel called in the US "Master of Space" to launch a two stage vehicle to the Moon.
The Yak--38 and -141 were developed for the Soviet aircraft carrying cruisers that didn't have a ski ramp because they used the fore deck for missiles.
In lectures about STOL aircraft around 1970 I learned that having the engine thrust contribute to lift is a good way to reduce take off length ( that notion was used in the prototypes of the Grumman A-6, but not in the series aircraft ). The professor then went on to show that you can use engine lift also by rotating the aircraft and that is used by the Soviet, Chinese and Indian ski ramp ships. He said that you naturally would use the same ski ramp on land IF you could be sure the wind would always blow in the same direction.
Vids of J-15's being launched show that their trajectory is pretty straight after leaving the ramp. They would dip if they lost an engine during take off but are likely to reach horizontal flying speed at a respectable altitude. They might then of course be forced to dump a heavy ordnance load.
You cannot say that US marines need F-35B because USS America has a length of only 844 feet (257.3 meters). CdG has a length of 261.5 m and uses ordinary naval aircraft and a cat only slightly shorter than the USN variety.
You can reduce the length of the cat and the size of the ramp by combining both. The front fifty meters of the ship will then be dedicated to take off and will not be available for spotting aircraft. I think a medium sized flattop, like the USN LHA's, can live with that. But there is a political problem.

 

[Kurt]

I see the issue not only from a technical perspective. There is a development of a medium sized aircraft carrier for mixed airwings of fixed wing fighters and helicopters. The helicopters operate as delivery vehicles for assault troops, while the fighters serve as air cover. This is one of the flattops of the future because it is pursued by different nations with major investments such as the UK and the USA (first two LHA) with others copying the mix, such as Brazil, Russia and India.
Unlike a catapult-supercarrier of US-design, this medium sized mixed carrier can do without a catapult for the few fighters that do not primarily serve as bombers. STOVL and STOBAR are options. I presume newcomers to this field, who have no access to STOVL aircrafts will invest into STOBAR designs. It would take a combined major project of the SCO members to create something akin to the JSF with STOVL capability. (my favourite would be CATOVL)
The LHD/LPH is only in few cases combined with rather marginal fixed wing operations. As these ships operate in groups for amphibious assault, they likely can do without a fixed wing component if another flattop in the group provides that. The air assault does have limits in transporting heavy systems and supplies, making an ability to ferry by boat across the sea indespensible for amphibious forces. As such the mixed aircraft carrier itself has been rightly called commando carrier, a better description for th role without other amphibious assets. In combination with an amphibious vessel with a well deck, it matures into an amphibious assault group. Please note that there are other designs than flattops for utilizing the well-deck. And helicopters hardly qualify as transport for anything, but infantry and jeeps.

 

[chuck731]

Chinese interest in the harrier dates back to late 1970s, China had also just emerged from the culture revolution and begun to examine critically the ideological doctrine of people's war, which Mao used to justify why the lack of technological progress during culture revolution did not threaten china's ability to defend herself against modern threat. y. It was beginning to become both clear, and acceptable to say, that china's ability to resist a soviet mechanized thrust into northern china under the cover of frontal aviation was extremely weak. Furthermore china was beginning to realize how poor it was relative to the rest of the world and how much it takes to offset soviet military capability in east Asia.

People's war was a illusion, so china needed a asymmetrical solution that is technologically adaquate and which china can afford. china initially took her cue from smaller, but technologically sophisticated countries on soviet border, such as Sweden, on how to formulate a small but technologically adaquate force that china can greatly complicate soviet planning, and which china can potentially afford in the short run. They decided china had no chance of maintaining control of the air in contested battle space against soviet frontal aviation covering a land invasion of china. So conventional aircrafwound Chinese military airfields would likely be rapidly destroyed by the soviet Airforce in the opening day of any conflict. So it behoves them to develop VTOL or STOL aircraft that can avoid destruction from soviet air power through dispersal, such as Swedish viggen and British harrier, and thus remain available to exploit gaps in soviet tactical air cover during a soviet invasion.

 

[delft]

I see the issue not only from a technical perspective. There is a development of a medium sized aircraft carrier for mixed airwings of fixed wing fighters and helicopters. The helicopters operate as delivery vehicles for assault troops, while the fighters serve as air cover. This is one of the flattops of the future because it is pursued by different nations with major investments such as the UK and the USA (first two LHA) with others copying the mix, such as Brazil, Russia and India.
Unlike a catapult-supercarrier of US-design, this medium sized mixed carrier can do without a catapult for the few fighters that do not primarily serve as bombers. STOVL and STOBAR are options. I presume newcomers to this field, who have no access to STOVL aircrafts will invest into STOBAR designs. It would take a combined major project of the SCO members to create something akin to the JSF with STOVL capability. (my favourite would be CATOVL)
The LHD/LPH is only in few cases combined with rather marginal fixed wing operations. As these ships operate in groups for amphibious assault, they likely can do without a fixed wing component if another flattop in the group provides that. The air assault does have limits in transporting heavy systems and supplies, making an ability to ferry by boat across the sea indespensible for amphibious forces. As such the mixed aircraft carrier itself has been rightly called commando carrier, a better description for th role without other amphibious assets. In combination with an amphibious vessel with a well deck, it matures into an amphibious assault group. Please note that there are other designs than flattops for utilizing the well-deck. And helicopters hardly qualify as transport for anything, but infantry and jeeps.

An aircraft that can be trapped will be superior in configuration, price and maintenance effort above one that lands vertically. But I do see a future in medium sized flattops, initially with gas turbines, later also with molten salt Thorium reactors.

 

[Kurt]

An aircraft that can be trapped will be superior in configuration, price and maintenance effort above one that lands vertically. But I do see a future in medium sized flattops, initially with gas turbines, later also with molten salt Thorium reactors.

Operations make the difference. A trapped aircraft has a long and complicated recovery procedure in comparison to vertical landing. This translates into less sorties per day per aircraft. STOBAR with the Eurofighter was one of the discarded options for the Queen Elizabeth class because it offered less capability to have assets in the air as required.
Vertical landing does reduce the payload, but maximum payload seems not the most utilized feature, especially if going for air defence. Thus the VL system reduces bombload or fuel or both in a STOVL variant, but it can resortie from the carrier with fresh fuel and armament really quickly. Flight to a target within normal range does not take long, making recovery for relaunch the component that limits useability of a system. Trapped recovery makes more sense, the further away targets are in flight time measures. Thus for commando carriers with helicopters long distance fighters are no useable utility, they need short range cover in qucik succession - STOVL systems. Trapped recovery makes sense as soon as you have a large air fleet that is fueled in flight to strike without other arms at a distant target. A mixed carrier with trapped recovery makes little sense for amphibious operations close to shore, but has utility as a sea-control-ship that stays away from shore.

In this regard, the vertical landing is a feature for amphibious warfare, while trapped recovery is economic in blue water naval operations if you have a big enough carrier. That's also the way both systems are currently being employed.

Catapults could negate some of the current disadvantages of short take off systems of either vertical or trapped recovery because short take off runs counter to high take off weight with payload and fuel for extended operations and limits the aircrafts rather to air defence, although the quicker sortie rate for STOVL does allow rapid switch of roles, unlike slower trapped systems.

Current development is towards shorter range of ship based aircrafts, including for aircrafts that are trapped, such as the JSF on supercarriers. This development does favour a vertical landing system, especially if it is about a mixed multi-role flattop such as the LHX. A vertical landing can do with less downward thrust than a vertical take off capable system if vertical landing is just designed for shipborne rolling "vertical" landing

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that is rather a controlled flight below stall speed (including slowed fall and "slow" movement forwards).
As a side note, the mobile landing platform offers a new well-deck concept for hovercrafts that could fit also better with flight operations.

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Sweden did not envison operations far from friendly shore, China would, in case of confronting a naval power, have to project power throughout the Indian Ocean. The Sweden model was only aplicable to the contest with the Soviets. One lesson to be learned from the Swedish is the utilization of an army of conscripts with little professional manpower, capable of operating complex systems such as jet fighters. For this reason, Sweden does have their own brand of rugged simple STOL fighters capable of contesting aerial supremacy against the odds, an idea that can certainly be credited to the Finnish airforce's performance during the Winter War (a good example on how to fight a superior enemy).

 

[bd popeye]

Re: PLAN Carrier Construction

I think a LHD/LHA is much more suited to disaster relieve than a CV, it is not that threatening, can bring a lot of relief workers on the soil, integral with hospital facilities and water purification facilities.

These are awsome diplomatic tools.

An LHA/LHD is well suited for the type of operation you describe.

A CV can do all those things... An Nimitz class can make 400,000 gallons of fresh water a day. She may not have the hospital facilities of an LHA/LHD but they are more than adequate.

Long ago I posted that an LHA/LHD would suit the PLAN well as they could asset neighboring nations with disaster relief.

 

[chuck731]

Re: PLAN Carrier Construction

A CV can do all those things... An Nimitz class can make 400,000 gallons of fresh water a day. She may not have the hospital facilities of an LHA/LHD but they are more than adequate.

An LPH or LPD can put large amount of supplies and vehicles on the ground. A carrier might be able to serve the initial relief, actual heavy duty rescue and sustained relief is much better done by LPH or LPD.

 

[bd popeye]

Re: PLAN Carrier Construction

An LPH or LPD can put large amount of supplies and vehicles on the ground. A carrier might be able to serve the initial relief, actual heavy duty rescue and sustained relief is much better done by LPH or LPD.

I do not like to argue.

I agree that an amphib is better suited..An carrier will do similar duty..... read about Operation Frequent Wind, 2004 Boxing Day Tsunami relief by USS Abraham Lincoln and recently USS George Washington during Operation Damayan.

I think one of the best benefits of having an LPH/LHD/LHA or even an LPD during humanitarian efforts is the well deck makes transporting service, people, vehicles & supplies to shore much easier. With a CV everything must be airlifted.