Can ASW be
effectively conducted by a surface vessel without a helo? Let’s analyze the concept and see.
A good place
to start any analysis is by looking at history.
History has much to teach us if we’re willing to learn.
In WWII, ASW
was conducted by a variety of platforms ranging from small corvettes to
destroyer escorts to destroyers to full fledged hunter-killer ASW groups
centered around small aircraft carriers.
Even sailing ships and small commercial vessels took part in the ASW
effort! These efforts were supplemented
by carrier and land based aircraft of all sizes and types.
Interestingly,
none of these ships had helos!
The backbone
of the WWII ASW effort in the Atlantic was the
corvette. The British Flower class
corvette was a good example of the type with 267 (numerically, almost equal to
the entire US Navy fleet today!) being built during the war. These small ships were not individually supremely
capable at ASW but they were effective due to their numbers and presence. A submarine will go far out of its way to
avoid detection. With enough corvettes
around, a submarine can be forced away from potential targets or suppressed
enough to allow the potential target to safely pass the submarine by – a
mission kill on the submarine. Even if
the corvettes never detected the enemy sub, their very presence was often
enough to “defeat” the sub.
Another
lesson from WWII and the Cold War against Soviet submarines is that ASW is not
conducted in isolation, one ship against one sub. ASW is a team effort. Just because a ship does not have a helo
attached does not mean that it cannot call on aircraft when a submarine is
detected.
Having
acknowledged some historical lessons about ASW, let’s now turn to the
fundamental question, what are the characteristics that make helos effective in
ASW? The answer is speed and standoff.
Speed – The speed of a helo, relative to
the speed of both the submarine and the helo’s host vessel, is much greater
than either and that confers an enormous tactical advantage to the helo. The helo can reposition faster than the
sub. The helo can dart from location to
location while finding and fixing the sub’s location while the sub is limited to
ponderous, slow movements by comparison.
The same speed advantage applies to the helo’s host vessel which can
only move at the same speed as the sub and cannot readily gain a positional
advantage.
Standoff – The helo’s relative immunity to
counterattack by the sub, coupled with the helo’s range, allows the host vessel
to remain out of effective range of the sub.
Thus, the prosecuting ASW ship gains a standoff advantage over the sub. The ship can attack via its helo while
remaining at a safe standoff distance.
That suggests
that helos should be included on every ship.
Is that really the case? No, it’s
not.
The problem
with equipping every ship with helos is the cost. A helo requires around 70 ft of added flight
deck length, 70 ft or so of hangar, fuel storage, munitions storage,
maintenance spaces, parts and tool storage, berthing for the twenty or thirty
additional pilots and maintainers, larger galley space to support the aviation
crew, larger food storage, more fresh water generation and storage, and on and
on.
A thousand
foot flight deck to operate fixed wing strike fighters is a highly effective
system. It’s not even debatable and yet
we don’t put those on every ship. Why
not? Cost. So, why would we think we have to put helos
on every ship?
As we noted,
helos add enormous costs to a ship. If
you take the helo component away from the LCS, for example, what you have left
is a Cyclone class PC which cost $15M-$20M when they were built. Okay, that’s not an exact match but it’s not
that far off. The point is that the
financial impact of a helo is immense and unaffordable.
That’s all
well and good but if we don’t put helos on every ship, won’t our ships be sunk
as fast as submarines can reload their torpedoes? I mean, after all, enemy subs will be lined
up waiting for our ships to run the submarine gauntlet – I’m guessing one sub
in every square mile of ocean, if submarine alarmists are to be believed. Our ships will have no hope, whatsoever.
Of course,
that’s absurd. For the foreseeable
future, China or Russia would be hard pressed to keep ten or twenty subs at sea
at any given moment in a war. China, for
example, has around 60 attack subs of which a dozen or so are SSNs and the
remainder are SSKs of varying age and capability. So, the submarine population density in the
ocean is almost non-existent. Of course,
submarines don’t just randomly distribute themselves throughout the ocean. They congregate at known convoy paths,
chokepoints, and transit locations. That
has the effect of increasing the apparent submarine density, somewhat. That still, however, results in a remarkably
submarine-free ocean.
Consider the
WWII U-Boat experience. Contrary to
popular impression, despite Germany’s large submarine force (almost 1200
U-boats built from 1935-45), submarine encounters were not all that common.
In all, during the Atlantic Campaign
only 10% of transatlantic convoys that sailed were attacked, and of those
attacked only 10% on average of the ships were lost. Overall, more than 99% of
all ships sailing to and from the British Isles during World War II did so
successfully. (1)
So, despite
an incredible fleet of 1200 U-boats, vectored to well known convoy routes, submarine
attacks were relatively uncommon. China,
with a fleet of 60 odd submarines, will simply not have enough subs to mount
more than occasional nuisance attacks.
Submarine
alarmists also proclaim that the US carrier fleet will all be torpedoed and
sunk within an hour of the start of a war.
Is this really the case? Are
warships that susceptible to submarines?
No, they’re not. Not even a little
bit.
As always,
let’s turn to history for some data. How
many warships did the US Navy lose to submarines? The answer is very, very few. The US Navy had a fleet of 6000 ships and
lost around 21warships to enemy submarine attacks.(2) In addition, a handful of small patrol boats
were also lost. Of those 21, one was a small
carrier (Wasp), two were escort carriers, one was a heavy cruiser, one was a
light cruiser, and the rest were destroyers and destroyer escorts. That’s
it. That’s the entire loss to enemy
submarines. Of course, there were a few
additional sub attacks that resulted in damage but not sinking. As a point of reference, Japan built around
200 submarines for WWII.
Those 21 or
so warship losses represent a loss rate of 0.3% of the total fleet. That’s an utterly insignificant loss
rate. That’s approaching zero losses!
So, why was
the warship loss rate so small in the face of a thousand U-boats and a couple
hundred Japanese subs?
The answer is
that because warships don’t travel repetitively across the same predictable
paths, as convoys do, submarines can’t congregate against them. Encounters tend to be random or the result of
a warship being operationally ‘anchored’ to a location such as the Wasp which
was ‘tied’ to the Guadalcanal operating area which allowed enemy subs to
congregate. The fact is that warships,
by the unpredictable nature of their operations, are very hard to find.
In addition
to being hard to find, warships travel much faster than convoys. A WWII convoy would travel at around 12 kts
or so. Warships tend to travel around
18-20+ kts. This makes achieving an
intercept solution very difficult for a submarine even if the sub detects a
warship. If the sub speeds up to achieve
an intercept it becomes louder and more detectable. Unless a warship has the bad luck to,
literally, stumble across an enemy submarine, the risk from subs is very low.
There are
some who will claim that modern subs are quieter, faster, and have better
sensors so ships will be helpless before them.
Well, this would be true if ships hadn’t progressed at all since
WWII. However, they have. Modern ships have helos, better sensors,
better fire control, networked data sharing, better sonobuoys, bi/multi-static
sonobuoys, etc. Thus, the performance gains
by submarines since WWII are offset by the gains by surface ships.
Nothing has
changed today in the submarine/anti-submarine battle. Subs still have a hard time finding warships
in the open ocean. Subs still have to
maneuver to achieve weapon launch positions.
Submarines still make more noise when they speed up.
None of this
should be construed as implying that the submarine threat can be
dismissed. The threat is real and
deadly. However, a logical analysis
demonstrates that the threat is nowhere near as common or automatic as
submarine alarmists would have us believe.
The combination of substantially fewer enemy subs than were operating in
WWII and the inherent surface ship advantages of unpredictability and speed
guarantee that the threat is not particularly prevalent. Thus, and this is the key point, not every
ship needs helos!
Inevitably,
some readers will interpret this to mean that ComNavOps is against helos on any
ship. Well, that’s absurd. Aside from the fact that I haven’t stated
that, it would just plain be foolish. We
need ASW helos – just not on every ship.
What ship(s)
should have ASW helos? I’ve discussed
this in previous posts but, to briefly recap, we need helo-equipped
hunter-killer ASW carriers and true helo-equipped destroyers, not the
cruiser/battleship Burkes that are tied to high value AAW escort duty and are
too expensive to risk in ASW.
The lesser
destroyer escorts and ASW corvettes (see the blog Fleet Structure page),
without helos, fill the role of presence and suppression, as discussed above in
the example of the WWII corvettes.
So, what have
we learned from the preceding discussion?
- The submarine threat, while serious, is vastly overblown as regards frequency of encounters.
- The main submarine threat is to convoys which follow repetitive, predictable routes.
- Due to their speed and unpredictability, warships are unlikely to encounter submarines.
- Effective ASW is as much about suppression as detection and attack.
- Based on cost and the unlikely chance of submarine encounters, not all ships need ASW helos and there is no justification for such.
(1)Wikipedia,
“Battle of the Atlantic”, retrieved 22-Nov-2019,
https://en.wikipedia.org/wiki/Battle_of_the_Atlantic#Outcomes
(2)Wikipedia,
“List of United States Navy Losses in WWII”, retrieved 22-Nov-2019,
https://en.wikipedia.org/wiki/List_of_United_States_Navy_losses_in_World_War_II
Maybe the new Secretary of the Navy will be better than Spencer on Fleet structure and effectiveness. He didn't resign over the Ford elevators, but asked to go anyway.
ReplyDeleteIn WW2 the Royal Navy lost 2 battleships, 3 Aircraft carriers, 4 Escort Carriers (two total constructive losses), 9 cruisers and 33 destroyers to enemy submarines.
ReplyDeleteWith the Mediterranean being where the majority of larger ships where lost to Submarines.
Would operating surface ships in the South China sea be comparable to the Mediterranean operations of WW2?
If we're going to park warships in a restricted body of water which would allow subs to congregate then, sure, we'd lose ships. That would, however, be an absolutely idiotic thing to do until the sub threat was greatly reduced.
DeleteNice post, but I do agree with Steven on this point. Taking US ship losses by submarine and comparing it to the total number of ships at the end of the war is not an accurate picture of submarine effectiveness. Two thirds of all carrier and battleship losses for the Royal Navy came at the hands of axis submarines.
DeleteThe effects on shipping were also extremely effective at the most uncertain time (ca. 1940). The allies were decimated by the attacks on shipping in the summer of 1940, to the point where Churchill had real concerns of a blockade that would suffocate Britain.
"not an accurate picture of submarine effectiveness."
DeleteNo one is saying that submarines are totally ineffective!
"Two thirds of all carrier and battleship losses for the Royal Navy came at the hands of axis submarines."
I'm only posting about US Navy operations. The British fought a different war, under different circumstances. Their experience does not apply to US Navy operations.
"The allies were decimated by the attacks on shipping in the summer of 1940,"
That's like saying we lost a game of baseball 15-1 but we were leading 1-0 after the first inning. Well, if the game had ended after one inning you'd have won, but it didn't. The submarine threat reached a peak and then receded as the war continued and the Allies developed countermeasures. Sure, any given day or any given convoy may have been in trouble but over the course of the war, subs were a serious but not common threat.
It's more like being realistic that while won the game in the end, we almost got slaughter-ruled in the 2nd inning...
DeleteA dipping sonar UAV that could be carried by small corvettes without a hanger would be another option. If you keep the dimensions of the dipping sonar as the basis for the design the UAV would look like a flying telephone pole. The upper portion would be the rotors,motors and the communication equipment. The lower portion the reel, cable and the dipping sonar head. The dipping sonar could be released and the UAV could land on the water to conserve energy while the sonar is active. Then fire up again to move to the next site. If a threat is found a similar UAV with a torpedo could be sent or just call in help from a nearby ship or P-8.
ReplyDeleteThis is similar to what I am thinking just much larger for ASW . The blades would fold along the length of the UAV when stored.
https://www.ascentaerosystems.com/spirit
Also a link to a Jane's article on dipping sonars.
https://www.janes.com/images/assets/541/51541/Active_dipping_sonar_technology.pdf
Interesting drone. Thanks for the link. An A-size sonobuoy is 3 ft long and weighs around 40 lbs. It would require a massively larger drone of the type you're suggesting. The drone would, presumably, be 8 ft long or more, several inches to a foot-plus in diameter, and weigh a hundred pounds or more. That's starting to move out of the realm of small, light, and simple.
DeleteUnderstand Ultra has developed a miniaturised sonobuoy which looks like a quarter the size of the standard A size.
DeleteVideo shows a large UAV with 30 tube launchers under each win, maybe a possibility that a small ship UAV eg Scan Eagle, could be developed with payload for one or two of the miniaturised sonobuoys, depends on its capability if worth the effort/expense.
https://www.youtube.com/watch?v=bltGGJJBOE0
"payload for one or two of the miniaturised sonobuoys,"
DeleteYou understand just how ineffective one or two sonobuoys would be, right?
A Skeldar sized UAV with sonar could be equipped to all ASW platforms. The small size, low coast and easy operations would allow the ship to move around one airborne senor. Should also not take to much space on the ship.
Deletehttps://en.wikipedia.org/wiki/Saab_Skeldar
Developing on the required sensor it should be easy to develop something similar.
/W
What do you think such a UAV could carry that would be tactically useful?
DeleteNick,
DeleteThanks for the link to the mini sonobuoy video. The video showed the exterior of the mini buoy showing a weight of 4 kg. I went to the website and couldn't find a product sheet with data so I don't know if that is accurate for the mini sonobuoy.
Assuming 4 kg for the payload, a UAV reusable sonobuoy may be possible with an increase in the size of the Spirit drone in the link above. Sizing would really depend on the range that you wanted to be able to send the drone away from the ship and still have it recovered. I don't have an idea what range would be needed to be effective and since we don't currently operate this way, it may take some war gaming to figure out the range needed. Propulsion could be electric if the range is not too great and internal combustion if greater range is needed.
The UAV sonobuoy could be recovered on deck or scooped out of the ocean if directed to land near the ship.
In regards to the telephone pole sonar drone; that sounds like something that could be stored and launched from a large VLS cell. Hoist it up a foot or two, Attach a set of compound rotor blades, and off it goes. Land in the water next to the ship for recovery, make them Semi-expendable. An ASW frigate could carry a half dozen or more.
DeleteAs a back up; VLS launched expendable sonobouys could be developed. 5-10 mile range, packed 4x in a MK-41 like ESSM.
"stored and launched from a large VLS cell."
DeleteCome on, now. Think this through. No ship is going to give up precious VLS cells for sonobuoys.
That aside, think through how many dozens of buoys would be used in the normal prosecution of a possible contact and then multiply that several times over in a war where every faint contact has to be assumed to be hostile and prosecuted. Sonobuoy usage rates will skyrocket.
So, for even a 'simple' attempt at localization, you'd need a couple dozen buoys or more. How are you going to get that out of a half dozen or more of these drones?
It also sounds like the drones are a one-use item. They can be recovered but not reloaded in a cell without a crane mechanism and the US Navy gave up on that concept long ago.
Give this whole idea some more thought and let me know what you come up with.
Can the sonobuoys be launched from the ship itself via a rocket or gun.
Delete"Can the sonobuoys be launched from the ship itself via a rocket or gun."
DeleteCurrently, no, but it wouldn't be hard to build a trainable launcher of some sort. Range would be the issue. If you can only 'shoot' the buoys 1-10 miles from the ship, you haven't gained all that much. Your ship is already in range of any possible sub. You'd like to be deploying your buoys dozens of miles away.
Hmm … Zumwalt … gun with no ammo … sonobuoys … $8B sonobuoy launching ship?
The average Helo packs 25 sonobouys. In a 4pack per cell configuration that would require 6 cells to equal one helicopter load of bouys. So if our little corvette has, say 10 cells, we can load the remaining cells with 16 ESSM for self defense. Or 8 ESSM and 2 harpoons. Alternatively we can load our sonobouys into a SEA-RAM style launcher.
DeleteI'm assuming our no-helo corvette is packing a hull sonar and/or towed array. The sonobouys are acting in conjunction with or as a backup to the main sensors. If they're particularly loud and obnoxious sonobouys they can be used to deter or herd enemy subs away from targets or into traps.
Another option for a no flight-deck corvette is a sonobouy shooting, dipping-sonardunking USV: an unmanned RHIB or speedboat. The validity of this idea depends on whether or not the unmanned boat(s) require less space and resources than a helo.
"Hmm … Zumwalt … gun with no ammo … sonobuoys … $8B sonobuoy launching ship?"
DeleteSomeone could go far in today's "industry" with that concept.
Well good post, absolutely no argument. Now the question is will the new Secretary of the navy boldly propose that LCS procurement be halted and the FF(X) program be altered to be some 40-80 inexpensive ASW (with surface warfare ability) DEs with say 4-5 DE leader helo carriers?
ReplyDeleteIm not sure but weren't some of the wwII Essex class converted to helicopter carriers or was it a different design
ReplyDeleteYes, several of the Essexes were converted to ASW and amphibious assault versions.
DeleteMaybe a ship along the lines of the British invincible class is a starting point
ReplyDeleteWell anti sub operations is what it was built for.
DeleteI think your concept is fine, especially with the ability to distribute remote sensors via UAV or otherwise. As for the statistics, I think it more relevant to look at the war in terms of where most of the contest was decided. 2 carriers lost to subs in 42 (If counting Yorktown). In the Atlantic, the sub war was in the bag before D day.
ReplyDeleteHow well could corvettes function in open ocean operations across the specific? How small is too small (even if apart of a larger group) before you run into problems? What are the constraints (crew sanity/sea sickness, supply stores, fuel, etc.)? It seems like 1500 to 2000 tons was sort of the smallest ships were made if expected to operate in blue water. Is there a reason for this? Could a 500 ton ship carry enough fuel (and the necessary ASW equipment) to operate thousands of miles from port?
ReplyDeleteResearch Flower class corvettes.
DeleteYes, I have come across the Flower class. With a range of 3,500 miles at 12 kts, it didn't seem viable in the Pacific.
DeleteThe medium endurance cutters that were put up for the Coast Guard's Offshore Patrol Cutter may be too large for an ASW corvette but the designs have the range that would be useful for the Pacific. Get rid of the helo hanger and it should be less expensive. They are larger than the Flower class but you might be able to have some shipyard competition since the OPC program is going to be restructured and the rest of the ships after the first 4 are open for competitive bidding.
Deletehttps://www.forbes.com/sites/craighooper/2019/10/14/us-coast-guard-reorganizes-troubled-105-billion-25-cutter-program/#3cf443932eda
I liked the Vigor OPC but they didn't win the original contract. It was slightly smaller than the Heritage class cutter at 100 m and featured an X-Bow design.
https://vigor.net/news-press/vigor-unveils-innovative-design-for-the-coast-guard-opc
They used Flowers because they had to. You might get unmanned that size or a theater type for the Gulf, Baltic, or Med. Manned and in the North Atlantic that size will just have crews worn out.
DeleteThanks for suggestions.
DeleteAndyM, what makes them get worn out? The rocking of a smaller boat? The lack of creature comforts?
The Damen Offshore Patrol Vessel 950 is very similar in size to the Flower class corvette, but I have been unable to determine it's range. The Axe bow is supposed to perform better in heavy seas than a conventional bow.
DeleteCost will be an issue if large numbers are needed.
DeleteFast response cutter (47 m) --$65 million built in USA
Multi Service Offshore Patrol Vessel 1400 (72M) --- $50 million built in Romania for Tunisia.
Offshore patrol cutter (Heritage class 110m) -- $420 million built in USA.
"didn't seem viable in the Pacific. "
DeleteThe Flower class is a starting point for a modern corvette design, not an end point. The distance from San Francisco to Pearl Harbor is 2400 miles and the distance from Pearl Harbor to Guam is 3800 miles so even a Flower class range seems viable.
"that size will just have crews worn out."
DeleteAnd yet we actually did it in WWII.
(Don McCollor) I remember Nicholas Monsarrat noting in the WW2 book "Three Corvettes"..."a corvette would roll on wet grass". Also US 110 ft (wooden) subchasers operated mainly in coastal waters, but they did cross the Atlantic under their own power.
DeleteYeah if a war is on we grab the offshore oil fleet and go, but people won't want to make a career of it.
DeletePut stabilizers on them. The technology is mature and not horrendously expensive.
Deletehttps://www.ship-technology.com/contractors/propulsion/naiad-dynamics/
I would tend to think a ASW task force could be the way to go it would be centered around small carriers say no bigger than the Izumo class include destroyer and smaller ships up to the size of LCS.
ReplyDeleteOf vourse after the admirals get done screwing with it would be all super carriers Tico cruisers and Burke destroyers to hunt subs with on convoy duty
Allied navies already have ample high end ASW frigates. They don't have the low end mass for convoy operations.
ReplyDeleteA large fleet of no helo corvettes would complement the Japan Maritime Self Defense Force as well as euro navies as well as our own P8 Poseidon.
More importantly, the corvette crews would train ASW full time and their officers would eventually take those skills to their destroyer commands. I say it's worth it just to maintain proficiency.
"More importantly, the corvette crews would train ASW full time"
DeleteIndeed! It's never about equipment. It's always about training.
Really great point.
JMSGF still has several non helo ASW corvettes, the Abukuma class, which they officially rate as DE. They used to have a lot more. Its a concept worth bringing back.
Deletehttps://en.m.wikipedia.org/wiki/Abukuma-class_destroyer_escort
"A WWII convoy would travel at around 12 kts or so. Warships tend to travel around 18-20+ kts. This makes achieving an intercept solution very difficult for a submarine even if the sub detects a warship."
ReplyDeleteThe tactical speed of a modern SSN is on the order of 20 to 25 knots and with long range anti-ship missiles, a submarine doesn't have to get very close in order to launch an attack.
No single sub carries enough anti-ship missiles to mount an effective attack against a US Navy (Aegis) surface group. To reach a torpedo launch intercept point will require sustained high speed and risk detection.
DeleteThe Russian Yasen-class can carry 32 to 40 anti-ship cruise missiles. While that is not enough to mount an effective attack against an Aegis surface group, it would be enough to attack a lesser formation, such as a convoy or an ASW group of corvettes and frigates. Perhaps enough to attack a small group of Aegis ships in transit.
DeleteYasen Class
DeleteAs you note, its effectiveness is limited to small targets and Russia has only 2 of them. Not much of a threat in the context of a war.
That's even more reason to build a lot of ASW platforms. The small number of existing (euro) frigates and destroyers are going to have to stay close to their convoy or carrier. A corvette flotilla could spread out and get the sub to launch from farther out.
ReplyDeleteASW helicppters only on the frigates and destroyers (and aircraft carriers).
ReplyDeleteOther ships would not have ASW capability, so there would be no need for them to have an ASW helicopter.
In my fleet, the new Perry class frigates would be the primary blue-water ASW platform. That would be their job, sub hunting. The long-hull Perry had two helicopters, I'd try and maintain that if I could (with the Perry's only having self-defense AAW and ASuW).
The Burke's would be the supplementary ASW platform, so I'd try and keep one ASW helicopter.
Corvettes would be too small to carry a helicopter, they'd need to be supplemented by a helicopter carrier.
I like the concept of submarine-hunter-killer groups. These could have corvettes and be escorted for self-defense by a Burke or two.
The ASW helicopter support would primarily come from a helicopter carrier. But this carrier would be a cheap ship only used for ASW helicopters, not turned into a jack-of-all-trades-mini-aircraft-carrier.
So a US version of the Hyūga?
DeleteKath, I had to look up what that ship was, I didn't realize someone had already put that idea into practice.
DeleteYes, by what I see on wiki that looks like what I had in mind. Thanks for the info!
Problem is the USN seems addicted to jack of trad-ism.
DeleteIt is somewhat counter-intuitive, but you want to separate your detection assets (ASW ships) from your prosecution assets (ASW helos). Otherwise, your helos will be at the bottom with your ASW frigate before they can even takeoff. Subs have an inherent advantage over ships in detection and will (almost) always get the first shot. You have to maximize the number of sensors and minimize the value of assets you put at risk to do so.
DeleteThe Hyuga as both a helo carrier and a tender to the smallest possible ASW corvettes is the ticket.
@that army guy: When talking about ASW it's always useful to look at what the JMSDF does; they're essentially an ASW-focused navy that does some ASuW and self defense AAW under some pretty strict financial and manpower limitations.
DeleteI disagree with ComNavOps in the deletion of a flight deck, however, for an ASW group built around an ASW helo carrier and corvettes. Steel is cheap, and the flight deck lets you temporarily stage your helos further out and push the endurance a little higher (instead of having them have to always return to the CVL to refuel), and if you need to upgun your corvettes or carry more weapons, well, isn't it a good thing you have that strengthened flight deck with a lot of deck area to install missile canisters...
To clarify, when I say flight deck, i mean the flight deck only. You don't need a hangar when you have the helo carrier serving as the main hub for the helos.
DeleteMV-22. A few years back there were various different variants proposed. SV-22 ASW aircraft, EV-22 AEW aircraft. A hunter killer group could be composed of a ASW carrier (improved Iwo Jima class).
ReplyDeleteAir group of 6 helos, 4 SV-22, 2 EV-22. 4 to 6 non helo ASW escorts and a Flt 1 Burke as flotilla leader for AAW and ASuW. Back in the day when we did ASW ops, we always had long range ASW aircraft around and a Carrier task force somewhere with in flight range, to back you up. A HK group would have back air elements as well, be it carrier or land based.
The Navy evaluated the V-22 as an ASW aircraft and rejected it. I never saw the reasons why it was rejected. One of the main problems is that the V-22 is not a hover-stable aircraft like a true helo. On the other hand, the S-3 Viking couldn't hover and it was a successful ASW platform. I think the V-22 is stuck in between - it can't perform like a helo and it hasn't got the range, speed, endurance, performance of a true fixed wing aircraft. It's sort of the worst of both worlds for the ASW role.
DeleteThe Japanese are the only people who'd really be interested in an ASW V-22, because it lets them push the ASW circle out, but at the same time they're fairly cash strapped with all of the recapitalisation and development programs going on. Whether rightly or wrongly, their MPA focus for now is the P-1.
DeleteI think it's still worth watching developments on that front - they're quite serious about the V-22 in JMSDF service beyond just being a troop transport - but it'll be a while before we see any developments of the sort (especially since the Japanese would be footing the bill for the sole development of a theoretical SV-22J).
On the other hand, their doctrine seems to think that their ASW needs can be covered by their MPAs. Certainly their airspace is a lot more permissable than trying to operate P-8s in the Taiwan Strait...
So see a fast non nuclear ship. ~18 Helos and able to defend itself. And someplace your F-35s can at least land on if one of you Fords gets sunk.
ReplyDeleteI could be wrong, but I don’t think carrier-based aircraft can land on a ship without an arresting cable (even in an emergency). They just can’t stop in time. If someone is more informed please correct me.
DeleteMy bad. I was thinking of just F-35Bs
DeleteKath, did you mean if the Ford's flight deck retaining bolts snap and the flight deck falls into the ocean?
DeleteActually, now that I think about it, the retaining bolts won't snap.
DeleteThis is the Ford.
The experimental electro-magnetic, anti-gravity fasteners will fail to operate...and the flight deck will fall into the ocean.
I think ASW is an area tat we need to emphasize more.
ReplyDeleteFirst, we need to bring back the S-3s, or something comparable and updated. I’d put 12 on each CVN, 6 for ASW, 5 for tankers, and 1 COD/utility. With 12 CVNs, that would be 144 aircraft.
Second, we need a dedicated ASW frigate (3500-4000 tons, $400-450 million). I would base the frigate on a long hull Perry, but with AEP or CODLAG for quiet running and 2 screws with enough power for 30+ knots. For sensors, I’d have basic surface search and air search radars, bow mounted multi-frequency sonar, VDS, SQR-20 Multi-function towed array, and wide aperture lightweight fiber optic sonar array (Virginia class side arrays). Front to back, I’d arm them with:
• 1x 76 mm Super Rapid STRALES/DART, where Perrys had missile launcher
• 2x RBU-like ASW rocket depth charge launchers just aft of 76 mm gun, may require moving bridge further aft
• 2x Mk32 Triple Torpedo Launchers, although I don’t believe these can be reloaded at sea – what I’d like to investigate is fixed tubes, like on the Knox class, with equipment to reload them at sea, like on subs; with homing torpedoes, you don’t really need trainable launchers; as long as I’m dreaming, I’d like to see if we could pair a 12.75” tube with a 21” tube, both port and starboard, with the ability to reload both.
• 32-cell VLS where Perrys had 76 mm gun, for 16 ASROC, 8 Tomahawk, and 32 ESSM (4-pack)
• 2 helicopters, or 1 helicopter and 1 UAV
Third, we need a dedicated ASW corvette (2000-2500 tons, $250-300 million) to provide ASW for shallow water, choke point, harbor defense, and convoy escort. This is not a carrier or surface group escort. Start with something like a Gowind or MILGEM Ada, minus the helos. It should have:
• 1x 57 mm, or 76 mm Super Rapid STRALES/DART if weight permits
• 2x Mk32 Triple Torpedo Launchers
• 2x RBU
• VDS
• Hull mounted multi-frequency sonar
• SQR-20 Multi-function towed array
I’d build 80 ASW frigates and 30 ASW corvettes. have 12 CVBGs and 8 SAG/HUK groups, total 20 combat groups, each screened by 1 cruiser, 2 AAW Burkes, 3 GP mini-Burkes, and 4 ASW frigates, so totals of 20 cruisers, 40 AAW Burkes, 60 GP mini-Burkes, and 80 ASW frigates. I’d have 15 littoral combat groups, in 15 ports along both coasts, Hawaii, and Guam, each with 2 ASW corvettes, 1 patrol ship (like Visby), 2 AIP SSKs, and 2 MCM ships (1 mother ship for drone/helo sweeps, like a mini-LSD/LPD, and 1 MHC).
Fourth, I’d build some kind of ASW helicopter carrier like the Japanese Hyuga. I’d build 8 of them, and they would be at the heart of my SAG/HUK groups.
Fifth, I’d take a look at the cheaper Kawasaki P-1 ($164 million) for combining in a possible high/low mix with the P-8 ($260 million). At those prices we could get 100 P-8s and 100 P-1s, for the cost of 163 P-8s, and they have different capabilities. The P-1 has a MAD tail and better low-altitude performance, while the P-8 is intended to operate at higher altitudes.
And I'd take all these out and train the heck out of them.
The frigate you describe can’t be had for $400-$450 million. I doubt it could be had for less than $1 billion. And, if a ship has standoff land attack capability along with area air defense, it isn’t a dedicated ASW platform. Throwing in those secondary functions seems innocuous enough, but doing so exponentially increases the complexity (and cost) of the ship overall.
DeleteYou also should consider what dictates the ship being so large. Powerful hull sonars and towed arrays can be operated by much smaller ships than 4000 tons. Why so big?
Lastly, consider the wisdom of basing helicopters on the same ship most likely to get sunk by a submarine.
Oh, it can be had for that. The Danes built something with more capability for less. The question is whether it can be had by the US Navy for that, and you may well be correct about that.
DeleteThe surface and air capabilities are meant to be self-defense and could be downgraded if that's overkill. I want it to be able to defend itself, but the only thing it needs to attack would be submarines.
As far as size, I was just starting with a Perry because it seems generally to be regarded as a decent ASW platform. We could probably start with a smaller Knox as a template, or maybe go even smaller.
The helicopters have to be based somewhere. This ship would typically operate with one or two carriers or a Hyuga-type ASW carrier, and helos could be cross-decked back and forth. I'm not putting helos on the corvettes, although the hulls I'm using as templates have them.
Actually, looking at it again, the Knoxes ended up not really being any smaller. I'm thinking it could go down to 3500 tons anyway, if not smaller. The only missiles I'm looking at would be ASROCs and air and surface self defense. I think the ESSMs work for air, and 4-packing them in Mk41 cells works, with probably Naval Strike Missile instead of Tomahawk for surface.
DeleteI'd see the general layout forward to aft as main gun, 2xRBU, torpedo tubes, VLS, 2 helos with CIWS atop hangar.
I do think IEP or CODLAG makes sense for an ASW plarfoem.
In other words that is exactly what I think LCS should have been
Delete"The Danes built something with more capability for less."
DeleteLet's be accurate, here! I assume you're referring to the Iver Huitfeldt. The publicly cited cost is extremely misleading and wouldn't even remotely translate to a US construction.
The hull was a reuse of the Absalon hull which saved a great deal of money. That wouldn't be the case for a US new design.
The hull sections were built in Estonia and Lithuania which 'artificially' lowered costs and, again, wouldn't be something that could be done in a US build.
Much of the weapons, sensors, and other equipment was taken from older ships and reused for free. Again, no applicable to a US build.
There are open questions about the degree of subsidization from the government and the degree of government furnished equipment that isn't included in the cited cost.
Those are just some of the issues I'm aware of.
Taking those factors into account, the best possible case for a new build in the US would at least double the cited cost.
Foreign shipbuilding costs should never be accepted and used without clearly understanding all the factors that go into it. In my experience looking at foreign costs, they are always significantly understated.
I'm aware of all those issues. But what I have in mind would be smaller and it would have a stronger sonar suite, but overall be less capable. We could probably find an existing hull form to use, although most would have to be modified for the bow sonar. And why can't we reuse some equipment?
DeleteI'm basically agreeing with you that there has to be a better and cheaper way to build ships than the US Navy does.
"there has to be a better and cheaper way to build ships than the US Navy does."
DeleteThere is. You get better and cheaper by building more ships (spread the overhead) which means design them smaller and single function. You get better and cheaper by building more ships more frequently (spread the overhead and reduce the profit margin per ship) which also means smaller, focused ships. You get better and cheaper by using more shipyards (more competition to lower costs) which, again, means building more ships and smaller ships. You get better and cheaper by designing ships that ONLY use existing technology. You get better and cheaper by LOCKING a design once construction begins - no changes, none, not at all, absolutely not under any circumstance - which means building ships with 15-20 year service life instead of trying (and never reaching) 40 years.
This isn't rocket science and I've posted on exactly how to do this.
Agree with more ships more frequently to amortize the design and other overhead. And more ships more frequently necessarily drives using more shipyards. I don't think you make them all small and single function, but I think there's definitely a place for a high/low mix of some bigger and more capable and some smaller and single purpose.
DeleteThe big differences are designing ships that use only existing technology and locking in a design once construction begins.
If you must do a Ford or Zumwalt or LCS, do one to test the technology, and don't do any more until you have proved that everything works. Rickover had the right idea--we had one-off Nautilus to prove nuclear power, one-off Albacore to prove the teardrop hull, and then Skipjack class to combine the two.
My problem with the 15-20 year life is that you may make an individual ship cheaper, but over a 40-year time frame you need twice as many ships to maintain the same fleet size, and sheer numbers can be very costly. I still like the idea of a 40-year life cycle, but a major maintenance and overhaul in years 20 and 21.
"My problem with the 15-20 year life"
DeleteYou completely miss the underlying concept of the 15-20 year life cycle. A 40 yr ship is hugely more expensive because you know you won't get more ships anytime soon. So, you pack everything you can think of into it and you build as much excess capacity, space, power, etc. into it as you can - most of which won't be used. You also have to provide much more maintenance or else you'll be forced to retire the ship early which is exactly what the Navy does. Most ship classes are retired early which means you paid for the 40 yr life and only used it for 25 (witness the tragedy of the Los Angeles class subs!). The 40 yr ships are always bordering on obsolete.
With a 15 yr ship you get the ship for half the cost, it's always got the latest tech, you don't have to do excessive maintenance, and you can change design direction on a frequent basis.
"you need twice as many ships to maintain the same fleet size"
No, you need the exact same number of ships. I think what you're saying is that you need to build twice as many ships which is correct. Of course, since each costs half the cost, twice as many works out to the same cost along with all the aforementioned attendant benefits.
What's your opinion on the Moskva class helicopter cruiser?
ReplyDeleteWould something like that as a command ship for the cheap corvettes be a good idea?
It tries to be too many things. If you want a battle line cruiser then build an optimized one. If you want an ASW helo carrier then build something a fraction of the size and complexity (and cost!) of the Moskva. Don't try to combine two unrelated functions. You'll wind up with a ship that's not good at either.
DeleteI was looking at it's helo carrying capacity more than it's weapon outfit so what about the French or Italian versions they are smaller ships or do you think something like HMS Ocean would be a better cheap ASW helo carrier to support corvettes?
Delete"HMS Ocean"
DeleteAgain, no. It's an amphibious assault ship with berthing for 800+ troops, 40 vehicles, landing craft, etc. Way to big for a ASW helo carrier. I understand that you're not proposing exactly that ship but just suggesting some general types.
Here's what is needed: The smallest, cheapest, simplest ship that can operate and support 8-12 helos and exercise command and control of their ASW ops. Nothing more. Nothing more. Nothing more. Anything more just adds cost and functions that don't directly support the main mission.
Yes but what would it look like? a very small carrier or one of the Helicopter cruisers that the European's built in the 50's and 60's?
DeleteI guess a diesel powered Casablanca class escort carrier sized ship would work but that still seems to big for just 8-12 helos.
"Yes but what would it look like?"
DeleteA Bogue class escort carrier is a good starting point. It's built off a cargo ship hull but should be shorter. The Bogue class was 496 ft long (439 flight deck) but that was to operate around 24 aircraft. For 8-12 helos, something around 350 ft might be about right. Any smaller and it won't be open ocean suitable (need a certain amount of stability to operate helos). Any larger and it's wasted space/cost.
The flight deck doesn't have to be capable of operating all 8-12 helos simultaneously. Perhaps 4 operating spots would be sufficient.
Going to have to disagree here on some aspects, CNO.
DeleteA Bogue-class couldn't handle 12 Helos optimally, it'd barely be able to handle 8 and you'd be suffering in performance — and that's assuming the flight deck only had 4 spots (which you'd be trying to commit murder to do - Helos don't like taking off or landing near other Helos).
If you were to shorten the ship even farther like you're suggesting, I think the ship would have trouble even keeping two Helos airborne.
That being said, that'd be two more Helos than Burkes manage to keep airborne.
See, there's a common misconception about the Burkes and Helos: People think because the Aircraft are deployed aboard the Burke that the Burke must be capable of maintaining those aircraft.
Simple fact is, that's entirely false — the Burkes are not actually capable of performing full maintenance of their airwing, they have to rely on nearby CVs to perform the heavy maintenance, all they can do is the equivalence of checking the oil and tire pressure in a car. Enough in day to day affairs, but any actual damage or serious maintenance has to be performed on a ship with an actual maintenance wing, which in the modern US Navy is only the CVs; and we both know the Navy's track record on shore-side routine maintenance: basically non-existent.
Therefore, you cannot attempt to approximate the deck and hanger space required for a single Helicopter on aa dedicated CHS (Carrier, Helicopter, ASW) by using the flight deck of the Burkes. That only tells you stowage and a single 'spot', it doesn't even remotely touch upon the full maintenance that any fully-fledged Helicopter Carrier ought to be able to handle.
A good model for a Helicopter Carrier of around the capabilities that you are asking for is the Japanese Hyuga.
It's fully capable of internal Maintenance of its standard airwing of around 12-16 aircraft (Globalsecurity's figure of '18-24 aircraft' must be a transport figure, they physically do not have the room in the hanger to carry and maintain that many active Helos), and it ONLY has 4 Deck Spots for Helos (and they are squeezing).
The much larger Izumo-class has only 5 deck spots (much more comfortably) and is the size of an Essex-class, but can carry a comparatively whopping 28 active aircraft.
It's a little hard for most people to accept (saying this for general readership), but the fact is Rotary Wing aircraft actually take far more space per aircraft than WW2 Fixed Wings!
...WW2 Fixed Wings that could do almost everything that the ASW Helos can do except hover.
In short, maybe we should be thinking less on ASW Helos and more on reviving the S-2 Tracker (which could land on an Essex with room to spare, as compared to the Jet-powered S-3 Viking which couldn't).
Same result, different method, better range and speed.
Sound's like it's time to modernise the Swordfish IV significantly smaller than a SH-60 with a 5+ hour endurance carrying 2 anti sub torps.
DeleteOr combination there of.
"A Bogue-class couldn't handle 12 Helos optimally, it'd barely be able to handle 8 and you'd be suffering in performance — and that's assuming the flight deck only had 4 spots (which you'd be trying to commit murder to do - Helos don't like taking off or landing near other Helos)."
DeleteWell, you can disagree but you'd be wrong. Opinion aside, actual facts demonstrate that a Bogue could easily handle four spots. The LPD-17 class has two spots on about a 170 ft flight deck which is 85 ft per spot. Thus, a Bogue size flight deck at 439 ft could accommodate 5 spots. I suggested a smaller vesion at around 350 ft which, doing the math, would accommodate 4 spots, just as I said.
Many other ships (Perry, Burke, Tico) have flight decks (1 spot) of 70 ft or so.
Even the America class LHA, whose spots are spread out to allow troop/gear assembly and loading (which an ASW helo wouldn't need), has ten spots on an 840 ft flight deck by using diagonally opposed spots on port and starboard sides of the deck. Thus, a Bogue, using port/starboard spots could possibly accommodate even more than 5 spots but, hey, let's not get greedy - 4 will suffice.
So, if you still 'disagree' then you're disagreeing with reality.
"Sound's like it's time to modernise the Swordfish IV"
DeleteYou're suggesting a WWII biplane?
CNO, I should probably explain where my perspective is coming from.
DeleteJust to be clear, I am not even remotely trying to be hostile with any of this post or the previous post, I am merely sharing my 'professional' input on the subject.
I am a (former) Naval Engineer who has worked on US Navy ship designs before; I won't state what firm I worked with, however I will state that I am intimately familiar with the America-class LPH, but not that familiar with the San Antonio-class LPDs.
Fact is that Flattops and Aftdecks are entirely different creatures when it comes to standards of operations and have different regulations, largely due to the wind interference provided by the presence (or lack thereof) of the Ship's Superstructure.
The San Antonio-class can get away with its spotting arrangement because it's an Aftdecker with angled spotting (although I call shenanigans on the claim of 4 spotting that flight deck, 2 spots is completely reasonable). Your short-hull Bogue absolutely could not because it's a Flattop — unless you wanted to go island-less and angle-spot, but every navy who has ever tried island-less CVs has hated them for many reasons I will not get into here.
For Flattop Carriers, USN Regulation requires 75' x 60' clearance (allowing off-deck clearance for up to 15' on one side) per Spot not including a REQUIRED 45 additional feet of DECK clearance (which excludes off-deck clearance entirely) on the fore and aft ends of the spot. That is, by regulation, 120' of flight deck per spot (plus an extra 45' on the end for the aftmost slot).
That gives a minimum of 525' length for a 4 spot flattop Helicopter Carrier, by USN Regulation, which is actually fairly aggressive.
This is due to safety hazards introduced by the height of the flight deck on carriers (and the lack of a wind screen), it has little to do with on-loading or offloading troops and equipment.
Now, I am aware that some of the flattops in service push things to unreasonable levels, but there is still a practical limit to how close you can push helos together: helos do not like landing or taking off close to each other, the rotor wash can and will interfere with nearby helos.
Additionally, the America-class LHA has 6 'spots' and 4 'stations', which are not relegated for take offs and landings but stand-by aircraft. Those stations are NOT designed for combat operations, they ARE NOT safe for such. This is one thing I can say with 100% certainty, they are NOT safe for flight operations.
That is so important that I will repeat myself: those stations are NOT safe for flight operations!
I don't care how they are used, this is fact: they are not meant for regular flight operations, at most they can be used to launch lightweight (mostly load-less SH-60s) aircraft for cross-ship transportation of personnel, but they are NOT reinforced landing points meaning they are NOT designed to take that shock!
They may take one, two, or a hundred landings, but they will fail much sooner than the actual built-as-such spots, and that's another thing I'm going to have nightmares about now.
It's not my 'opinion', it's the reality of mathematics and engineering; you are the one disagreeing with reality.
Incidentally, you can't just decided to use an aftdecker design to shorten the hull, either. The 2-4 spot aftdeckers (Haruna-class, Moskva-class, San Antonio-class) are still 500+ feet in length for a very good reason.
>> It's not my 'opinion', it's the reality of mathematics and engineering; you are the one disagreeing with reality.
DeleteIn hindsight, this could be taken as both rude and hostile. I apologize, that wasn't what I was intending.
As a naval engineer, I am curious what you think is the smallest vessel (both in terms of displacement and length) that could support a single 60k pound vertical takeoff aircraft. What would be the limiting factors and considerations?
Delete"by regulation, 120' of flight deck per spot"
DeleteThen explain to me how Burkes, Perrys, Ticos, and LPD-17s have flight decks that are 70 ft or so? LPD-17 is longer but also has two spots.
I can plainly see the spotting distances on the Wasp/Americas but there is no flight safety reason for it that I can see. They have huge flight decks so I assume they simply use more space because they have more space.
If anything less than 120 ft is unsafe then you'll have to explain the Perry, Burke, Tico, and LPD-17.
Also, for an ASW helo carrier, the number of spots is almost irrelevant. Unlike an amphibious assault carrier where the helos MUST assemble, load, and launch at, essentially, the same time, an ASW carrier could operate 500 helos (throwing in some hyperbole, there) with only one spot since the helos have no need to launch simultaneously. So, again, a Bogue size carrier is more than sufficient.
" that wasn't what I was intending."
DeleteNo problem! You're offering good information and I thank you for that. However, based on the observed flight deck sizes and spots for the classes I listed, I think your big deck amphib 'rules' are convenience rather than true safety. If you can explain how/why those classes can get away with 'violating' your rules, I'm perfectly happy to be persuaded.
"75' x 60' clearance … a REQUIRED 45 additional feet of DECK clearance (which excludes off-deck clearance entirely) on the fore and aft ends of the spot."
DeleteYou might want to check out the America starboard forward spot and the port aft spot. I don't have a dimensioned flight deck drawing but the photos don't seem to show anywhere near the clearance you've indicated.
Why not? one advantage of the swordfish was that it required a short deck for takeoff and landing and could take off and fly in rougher weather than the RN or RN used USN planes of the time.
DeleteSure modernise it, build it safer and from modern materials but keep it small and cheap.
You could have a combination of a few modernised S-2 Trackers and more cheap biplane or if you don't like biplanes how about new build A-1 Skyraider's for anti-sub work.
Aren't high end ultra expensive aircraft the reason the USN has less airwings than carriers now?
It has to be easier and cheaper to train people to fly those types of plane and another advantage unlike with the cheap ground attack plane anti-sub planes aren't going to be shot at unless things go very, very wrong.
He said why your examples are different - The superstructure on the ships you mention screen the wind whereas flattops don’t have that benefit. Also that multiple helicopters in close proximity create disruptive rotor wash and require more space to safely operate. The ships you mention (except the San Antonio) only operate one helo at a time.
DeleteI am also guessing those smaller starboard spots are the staging areas he was referring to.
Great information from him, though I agree it doesn’t really matter since you will not need to launch more than one or two helos at a time.
"superstructure on the ships you mention screen the wind whereas flattops don’t "
DeleteNo, he didn't actually say that. Possibly, he suggested it with a comment about wind screens although it's not clear what that meant especially since carriers routinely operate helos and have no wind screens. Interestingly, Soviet experience was that the superstructure on Moskva type helo-cruisers actually cause MORE problems by creating turbulence aft of the superstructure. Nimitz/Ford carriers have this same problem aft of their islands and landing aircraft have to fly through the turbulence. Finally, if wind speed is an issue, a carrier could simply slow down a bit as a helo was launching or landing. For a ASW helo carrier, launches and landings would not be all that frequent so it would impose no great impact on normal movement.
His other explicit explanation was deck height though he offered no explanation why deck height would be an issue and none come to mind. A Bogue class, for example, would not have much deck height compared to a Ford/Nimitz. Why an additional 10-30 ft of deck height would impose some significant added danger is unclear to me.
"staging areas"
Regarding the staging areas, I find it very hard to believe that the Wasp/America's flight deck is built stronger on the port side than the starboard. The incremental weight difference between a loaded and unloaded helo seems insignificant relative to the structural capacity of a flight deck that is built to handle the weight of dozens of parked aircraft.
In short, the information on spot spacing is interesting but the explanations defy common sense and are very difficult to believe. For example, the usable flight deck area on a Tico cruiser looks to be around 50-60 ft measured fore and aft and that is shorter than the length of a SH-60 type helo! It seems very hard to believe that we can safely operate helos on Ticos with 50-60 ft of space and yet REQUIRE 120 ft or more on a WASP/America. Does that sound right to you?
I think where the Bogue class or something smaller run into space problems would be providing adequate hangar and maintenance facilities. I think something like a Hyuga would provide sufficient hangar and maintenance space. Japan built them for about US $1B each, so I would think we should be able to make them for $1.25B-$1.4B, if we can keep the admirals and staffs from growing the scope.
Delete"I think where the Bogue class or something smaller run into space problems would be providing adequate hangar and maintenance facilities. ... Hyuga "
DeleteSo, you think a 646 ft Hyuga which can carry 18 aircraft has sufficient hangar facilities but a 496 ft Bogue with 8-12 aircraft can't have sufficient hangar facilities? Let's do the math. The Hyuga has 36 ft per aircraft whereas the Bogue (with 12 aircraft) has MORE room at 41 ft per aircraft! Admittedly, ft/aircraft is not a direct measurement of hangar capacity but it does indicate that a Bogue has more potential hangar space.
"$1.25B-$1.4B"
For a simple helo carrier?! That's why we can't afford our fleet. We have to stop buying more capability than we need. An ASW helo carrier is not a front line warship. Conceptually, it should be a converted cargo ship with a flat deck - nothing more. Industry routinely builds $100M giant tankers. Take one of those and make some modifications and you're done - say a total cost of $400M. Why do we keep gravitating to full fledged naval warships for 'half-fledged' naval missions?
@CNO
Delete>> Then explain to me how Burkes, Perrys, Ticos, and LPD-17s have flight decks that are 70 ft or so?
The Burkes, Perrys. and Ticos are both aftdeckers and only operate one Spot, they don't have to worry about interference from other Helos. Additionally, they're actually older than the 75' regs in question, which increased as the size of the helos did.
With single-spot helo decks, you only need to concern yourself with the 75' (68' for Burkes; Perrys and Ticos were designed with Sea Sprites in mind). The 45' between spots reg only applies to flattops with multiple spots.
As I said, I'm not that familiar with the LPD-17s, but from my understanding they took their required length from anglespot and actually do meet the width requirements.
>> So, again, a Bogue size carrier is more than sufficient.
I agree that a roughly Bogue-size hull is sufficient for the CONOPS you've specified if you do not require 4 spots, you'd still get two spots out of that and a healthy wing of 6-8 aircraft. I disagreed with the SMALLER hull.
>> You might want to check out the America starboard forward spot and the port aft spot.
These are the staging areas. They are lines painted on the decks so crews know where it's considered safe to park the aircraft.
On that topic:
>> staging areas
When an aircraft lands it momentarily applies force to the deck of between 5 (biplanes) and 13-15 (MV-22) times their own weight, rule of thumb figures. This is simply physics at work: hitting the floor after jumping applies far more pressure to the floor than merely standing on it.
You may find it hard to believe, but it's a fact. We cut corners with both cost and weight wherever we could, so the starboard side deck is not as 'impact resistant' as the port side deck.
Personally, I'd like to build everything to reasonable maximums, but that's 'battleship mentality' which is looked down upon by the Navy anymore.
>> height
Height affects wind speed on a moving object drastically. As little as 10ft above surface level can increase the felt wind speed by as much as 5kts, and that increaeses as the height increases, which can have a drastic effect at 45-50' up when you're already moving at cruise speeds.
Of course, you are correct, you could just slow down the CHS, which is an entirely reasonable action which I overlooked. I openly admit, I forgot to consider this. Flattops automatically get fixed wing profiles in my mind due to what I'm used to, and they prefer launching at 27+ kts. This is my error.
>> wind
Yes, the difference between a Flattop and an Aftdecker is primarily the 'wind screen effect' of the superstructure, if you want to call it that.
Said superstructure is both a blessing and a curse: operating inside that 'null area' is easier than in the open wind current, but passing through the 'wind wall'/turbulence is the problem. The turbulence is a known hazard, which is why most USN aftdeckers in recent years have had some form of assisted landing system for their helos (usually in the form of the RAST system). This makes the turbulence far more acceptable, as when passing through the 'wall' they have anchored themselves to the ship.
Ships with very large superstructures providing a 'wind screen' (LPD-17) actually don't need the RAST system as the Helo can move fully inside the 'null area' and then land while ignoring the 'wind wall' turbulence.
Incidentally, this turbulence is actually one of the reasons for the 45' between spots on flattops (in addition to the rotor wash), as parked Helos actually can generate turbulence. This isn't so much an issue when at low speeds, however, the primary concern being the rotor wash.
@Globe345
Delete>> As a naval engineer, I am curious what you think is the smallest vessel (both in terms of displacement and length) that could support a single 60k pound vertical takeoff aircraft. What would be the limiting factors and considerations?
Well, that depends, what are the CONOPS of the ship and the properties of the aircraft?
The former determines the considerations, the latter determines the limiting factors.
For aircraft, let's use a F35B (50k lb) that was given J/RATO equipment as a hypothetical example, even though it's not a proper VTOL.
If the ship wasn't expected to do anything else at all, merely act as a mobile launch/landing platform for a single aircraft, and was not expected to perform full maintenance on said aircraft: it would be entirely possible to place one on a hull that was roughly the size of a Sumner-Gearing (~380' length), just a couple feet wider (45' beam), maybe 3000-3500ts displacement.
If you expected the ship to perform full maintenance and keep that single aircraft up as long as reasonably possible, then you'd be needing a wider hull to allow full access to the aircraft, including with forklifts. So, you'd be needing a (guesstimate number) ~60' wide hull, but I believe the same length would work. You end up with a ~5500-6500ts hull. At this point, you'd be better off building a Long Island/Bogue and carrying multiple aircraft.
Thanks for the response. It just seems crazy to me a 50k pound aircraft requires a ship that displaces 100 times that amount!
DeleteI’m trying to understand the possibilities of a fast-sprinting ship that can act as a lilypad for one 50-60k pound V-22 tanker. Wouldn’t need hangar space.
I had something like the Spearhead class or Sea Fighter in mind, but it sounds like those ships are simply too small to support that much weight on the flight deck.
“An ASW helo carrier is not a front line warship”
Delete“"$1.25B-$1.4B"
So what is going to be the doing ASW for the combat fleets deployed in hostile waters? As I was conceptualizing this the saving came in not trying to have distributed helicopter lethality everywhere. So a type Hyuga as DE leader is expensive and makes and the goal to save money on its helcopter-less small DE consorts, that are focused on one thing ASW and also surface/anti-air/missle ships not having helo crews, or wasted space.
On the cost its that its doubtful that the US can beat Japan at cost. But that said the Hyuga is perhaps over built for a DE leader. If you want to eliminate their inherit ASW ability they would be less expensive.
But that leads to the Bogue
It seems to it rather slow. Has almost no sensors, nor any ability to defend itself sans aircraft. A simple design such as that would almost assuredly require one of its DEs to stand by closely to it. Or if hanging with a CV group be fast enough to do so. Also I would be curious to what extent the Bogue class could service its aircraft, or carry spare air crew? Its a post start of the war design with a very minimal set goals.
I would think speed would be important you really don't want the thing carrying all the ASW aircraft to go down.
“Conceptually, it should be a converted cargo ship with a flat deck - nothing more. Industry routinely builds $100M giant tankers. Take one of those and make some modifications and you're done - say a total cost of $400M. Why do we keep gravitating to full fledged naval warships for 'half-fledged' naval missions? “
Slow. Rather not agile. Likely to sink easily. A tad large as well. Also I think you are being generous on the cost. The MLPs dropped the ability to support helicopters almost immediately to keep the ~450 million cost.
What is half fledged navel mission? I thought one of the goals with the concept was to get the helo's off of the Burkes and mini Burkes and presumably avoid having to too many ASW helos on the CVs so that dedicates DEs and/or small corvettes would do the job for the fleets fighting wars. If you mean just inexpensive convoy escorts. I suppose it fits but than a Burke or more has to be around right?
"I thought one of the goals with the concept was to get the helo's off of the Burkes"
DeleteNo. You're mixing two separate missions together. An ASW helo carrier is NOT a battle group / carrier group escort. A helo carrier for a carrier group is redundant. The carrier, itself, has all the ASW helos needed and room for many more.
An ASW helo carrier has two purposes:
1. Convoy escort
2. Independent hunter-killer group