NavWeek: Speed Quest

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As the U.S. Navy revisits many of the requirements for its Littoral Combat Ship (LCS), it’s certainly time to reconsider the vessel’s need-for-speed concept. There is no question the Navy needs a fast ship for some of the proposed LCS missions –- the issue is just how fast the ship needs to go, and what is the service willing to give up for the ability to zip across the seas? Alternately,  perhaps the Pentagon should consider a whole new vessel as its maritime sprinter.

Officially, the LCS goes above 40 knots. When I was on LCS 1 USS Freedom last year, the ship was pushing it near 50, leaving any questions about its speed-demon status well in its wake.

Now, with Defense Secretary Chuck Hagel’s directive to make the LCS successor more lethal and survivable, Navy officials say they can dial that speed back a bit. But how much? The low 40s? High 30s. Mid-30s?

Navy officials will most certainly review Freedom deployment data from its Singapore swing last year before deciding that number. But they also should review –- and I’d like to think they would actually be re-reviewing -– some earlier reports on this Navy speed quest and the results thus far.

“The pursuit for high speed itself demonstrates an inherent bias toward the attribute of speed and the neglect of range and payload requirements,” writes David Rudko in his March 2003 thesis, “Logistical Analysis of the Littoral Combat Ship,” prepared for the Naval Postgraduate School at Monterey, Calif.

“Ideally, a small warship would be inexpensive and fast, carry a large payload and have high endurance and good sea keeping,” he writes in the published thesis. “Unfortunately, the current state of technology prevents this combination.”

He notes, “Throughout history, the United States Navy has invested a considerable amount of time and money in the development of high-speed ships.” Looking back to the 1960s, he writes, “The Asheville class experienced many problems throughout its life cycle.  In the design process, the tradeoff between speed, payload and range was a great source of debate and resulted in delayed construction.  Each ship cost approximately $5 million, five times greater than the initial $1 million projection, and high maintenance costs made them expensive to operate once commissioned. Additionally, sea keeping problems prevented them from capitalizing on the high speeds for which they were designed. The changes in missions they experienced throughout their service life demonstrated their inability to successfully fulfill the primary mission for which they were designed.”

Then came the Pegasus class missile hydrofoils. “The initial concept was to establish a squadron of missile hydrofoils, each carrying a different modular weapons package, capable of functioning collectively as one multi-mission conventional warship.”

He points out, “Due to the inability to incorporate a modular weapons capability into the missile hydrofoil design, the squadron concept never came to fruition and the missile hydrofoil’s limited role was not in keeping with the Navy’s emphasis on multi-purpose ships that were more adaptable to the full spectrum of naval operations.”

He says, “The more appropriate question is whether or not it is possible to overcome the limitations which have, throughout history, prevented previous high-speed ship designs from successfully capitalizing on any value that speed potentially offers.”

Rudko is not the only one to raise such questions. “Persistence in the quest for speed has involved hundreds if not thousands of scientists and engineers over many decades dedicated to developing new ship and vehicle technology to give the Navy credible high-speed options,” say Dennis Clark, William Ellsworth, and John Meyer in their 2004 report for the U.S. Navy’s Surface Warfare Center, Carderock Division, “The Quest for Speed at Sea.”

They write of the focus after World War II, “when the U.S. Navy began to seriously consider the value of proposed concepts for planing craft, multihulls, hydrofoils, hovercraft, and hybrids,” noting, “In the period 1970 to 1983, 327 fast attack units and 1,471 patrol craft were constructed and exported worldwide. Their excellent cost-effectiveness ratio, simplicity of operation, miniaturized electronics, and relatively heavy firepower attracted the attention of many navies, particularly those operating in restricted waters. The modern planing hull now has better seakeeping characteristics with little sacrifice in calm water performance.” 

In the mid-1970s, they say, “The U.S. Navy undertook an advanced planing hull research program aimed at improving seakeeping while retaining as much speed as possible and improving the lift-to-drag ratio of the hull through the mid-speed range.”

But, they say, “The aggressive and successful planning hull research program initiated in the early 1970s subsided in the late 1970s, when the U.S. Navy decided to emphasize acquisition of large combatants capable of transiting the world’s oceans. With this philosophy, problems can arise when we need to engage in limited warfare in areas where the larger ships cannot operate close to shore, or in the inner harbors or rivers.”

So the Navy pulled back from the research at the time when it really needed to step up such studies. “While many of the high-speed vehicle types described above have been in existence for many years, we have limited experience in their application in actual naval missions,” they report.

Another Carderock report from the Naval Warfare Center, the High-Speed, Small Naval Vessel Technology Development Plan, says, “It is unlikely that the full matrix of technologies will be developed... . Naval high-speed (40 to 60 knots) missions require extrapolation beyond current capabilities in critical areas such as structural loads, resistance and powering, and seakeeping.”

One program that proved, in the end, to be somewhat successful was the Cyclone-class patrol coastal (PC) ship. After essentially being dumped by the Navy -– with some of the ships going to the Coast Guard for a bit -– the vessels now are being used in a variety of missions and getting more lethal weaponry.

But the PCs are even less lethal and survivable than the LCSs. If Navy officials are going to consider those types of ships, it should look at whole new fast-ship concepts, considering different types of seacraft altogether. 

“Efforts to solve the seakeeping and ride comfort problems led, in the 1960s, to the small-waterplane-area twin-hull (Swath) ship configuration,” Clark, Ellsworth and Meyer write. “Although the Swath ship is an important development with a number of desirable features, it is not currently considered a high-speed concept.”

There’s a company in Portsmouth, N.H., looking to change that. Juliet Marine Systems has developed a prototype small-attack craft based on the Swath concept that looks something like a sea-skimming F-117 called Ghost that it is touting as a “poor man’s LCS.”

Credit: Juliet Marine Systems

The boats are certainly portable –- you can fit four of them in the well deck of an LPD 17 San Antonio Class amphibious ship.

The U.S. Navy has discussed the vessel with the company, CEO Gregory Sancoff says, but there’s been nothing official. There has, however, been international interest, he says.

“We have had many discussions about building a Corvette-sized Ghost to carry a crew and sophisticated weapons systems and missiles,” he says. “Ghost would be capable of operating in denied-access areas without detection, due to vessel design and by utilizing RAM (radar-absorbing material) coatings.”

He notes, “Ghost today can carry over 80 of Lockheed Martin’s Nemesis missiles in an enclosed weapons bay.”

The boat provides a huge advantage, he says, as missile thrust does not have to be redirected but can vertically exhaust in an effective and safe manner. “Ghost fires the missiles from an enclosed weapons bay and the thrust is directed down between the hulls, hidden from satellites and cooled by the ocean waters. The craft is ideal for missions requiring the ability to fire and sprint.”

Countries like Qatar do not need a destroyer or LCS, he says. “They need smaller tactical platforms that bring all the capabilities of LCS in a smaller package to protect their country and escort exports ships. Ghost can also carry two Mark 48 lightweight torpedoes if necessary.”

Of course, this late in the game, it appears unlikely such a novel concept has a ghost of a chance of being an LCS stand-in for the successor warship missions

Discuss this Blog Entry 5

on Jul 2, 2014

To use an aviation think 3D capability as a model to design a naval surface system limited to a 2D environment would seem to be dubious at best. A ship cannot just cut in the afterburners and head for the deck trading altitude (potential energy) for speed. Finding someone limited to a 2D environment is infinitely easier than looking for someone hiding amongst the hills, valleys, jungle, and plains. Who ever dreamed up this SPEED thing must have been ON it. The LCS was a flawed concept from the time they started making the ship LESS SAFE for our sailor, which broke the faith with them by placing them in a dangerous environment without the protections learned the hard way by sacrificing our most precious blood learning the lessons. The United States Navy needs an all ocean, multi-warfare, Aegis Guided Missile Frigate with a non-rotating AESA radar. . . also employing Directed Energy weapons.

However, I do like the Ghost. I would name it the Defiant.

on Jul 3, 2014

We are in a period following a war (or ten) that history has shown is the best time to develop new war fighting tools. The LCS is essentially a blank canvas on which the Navy is looking for the way forward. Virtually every existing ship is already outmoded in an era of missile swarms that make the Ford class immense targets. The Navy is quietly building a new class of ships that are also very adaptable, can carry Marines, F-35's, helps and the rail gun. Or something else. They know the LCS needs to change, they always did know, they just don't know how, what, where. Thus, they build a few and send them out. Interestingly, the major problems have been with old technology - the diesel generators. The Navy is looking very hard at the NEXT war, not the last, and the LCS does have one redeeming quality - it has enough power for the rail gun and the laser. Those two weapons are the key to that next conflict.

on Jul 5, 2014

Reliance on diesel engines baffles me. Too many moving parts that must all be spared and supported. Gas Turbines have much fewer parts, and are far more efficient when used correctly. They come online faster. The newer more efficient units are extremely fuel efficient. When the new energy storage devices come online the 2nd GTG on the cruisers and destroyers will not be required to run all the time. Hybrid Electric Drive (HED) enables a more efficient propulsion method at slower speeds which is what we are doing most of the time. I am not for a pure electric propulsion solution. The mechanical primary/backup method will be needed for some time. The HED propulsion system provides additional electrical power generation capability for Directed Energy (DE) weapons during GQ.

on Jul 16, 2014

Dear Mr. Fabey:
This is in response to your article “NavWeek: Speed Quest”. You state the following, referencing David Rudko’s March 2003 thesis, “Logistical Analysis of the Littoral Combat Ship,” prepared for the Naval Postgraduate School in Monterey, California:
“Then came the Pegasus class missile hydrofoils. “The initial concept was to establish a squadron of missile hydrofoils, each carrying a different modular weapons package, capable of functioning collectively as one multi-mission conventional warship”. He points out, “Due to the inability to incorporate a modular weapons capability into the missile hydrofoil design, the squadron concept never came to fruition and the missile hydrofoil’s limited role was not in keeping with the Navy’s emphasis on multi-purpose ships that were more adaptable to the full spectrum of naval operations.”
The commentary on PHM 1 (PEGASUS) Class missile hydrofoils is inaccurate. I begin by noting that the initial concept was not based on different PHMs carrying different modular weapons packages. PHMs were designed for the primary offensive mission of Surface Warfare, with self-defense capability against both surface and airborne threats.

The need for a relatively small, fast ship to counter the proliferation of Soviet and Warsaw Pact missile boats, such as the Soviet hydrofoil BABOCHKA was articulated in the late 1960s by NATO’s Commander-in-Chief, Southern Command. This requirement was researched by the appropriate groups within the NATO Naval Armaments Group (NNAG) ultimately leading to a tripartite agreement between United States, Federal Republic of Germany and Italy in 1972, for the design, development and acquisition of the NATO PHM. This program was strongly supported by ADM Elmo Zumwalt, who was then Chief of Naval Operations (CNO). PHM was to play a major role in his new “high-low mix” vision for the U.S. Navy’s shipbuilding program. In November 1972, the NATO PHM Project Office and Steering Committee were formed. The USN had the lead for design, development, and acquisition and chaired the three-nation steering Committee. Agreed basic operational characteristics for the PHM were as follows:

 Displacement: 250 metric tons
 Length: 132.9 ft
 Beam: 28.2 ft (hull) 47.5 ft. (foils)
 Propulsion: 1-LM-2500 (Foilborne) 2- MTU diesels (1630 hp) (Hullborne)
 Crew: 4 Officers / 19 Enlisted
 Foilborne Speed: 40+ knots, Sea State 0 40 knots, Sea State 5 (3.05 meter [10 ft] significant wave height)
 Hullborne Speed: 11 knots, Sea State 0
 Range: 750 nm foilborne at 40 knots/1200 nm at 11 knots
 Draft: 7.5 ft (foils raised) / 23ft (foils lowered)

Since the earliest days of planning, it had been expected that the ships would be utilized in NATO Areas of Operation, primarily the Mediterranean, with occasional excursions into the North Sea and the Baltic. This planning was consistent with and responsive to the original requirement enunciated by NATO in the early ‘60s. The absence of a dedicated support ship (among other things) to accompany PHMs on long open ocean transits, made the concept of overseas home-porting an attractive one compared to relatively frequent transits from the US to the European theater. Ultimately, the German navy decided in the early 1980s to instead procure 390-ton S-143 Class FPBs, some of which are still in service. Their decision was based primarily on unit cost, with acknowledgement that ship motions in heavy seas would impact combat system and crew performance. The Italians also dropped out because of cost and later purchased a squadron of 60-ton SPARVIERO Class hydrofoils between 1973 –1983 which have since been retired from service.

Delays in delivery of the production PHMs and concern about PHM 1(PEGASUS) material condition resulted in several cancelled trial deployments. PEGASUS was home-ported initially at Little Creek, VA in 1979, awaiting the arrival of her sister ships. In 1980 her homeport was shifted to Key West Florida where she could participate in the US Navy’s contribution to the “War on Drugs” while awaiting delivery of PHMs 2-6. The production ships and the shore-based, transportable PHM Mobile Logistic Support Group (MLSG) housed in ISO-size containers were delivered to Key West over the next three years, with the full squadron ( PHMRON TWO) being constituted in Spring of 1983. Concurrently, the Navy put the overseas home-porting plan on indefinite hold, in order to refine the PHM logistic concept, to develop tactics and generally gain more experience with the ships. This plan was never revisited, and for the next ten years PHMs operated solely in the Caribbean, western Atlantic and Gulf of Mexico. In that time the ships’ operational employment was similar to other USN ships operating in these areas:

• PHMs provided a two-ship detachment for Operation “Urgent Fury” in Granada.
• Every deploying Battle Group trained with PHMs- which were usually simulating opposition forces (e.g., Boghammars in the Persian Gulf).
• Port Visits in the Caribbean and in the US from Texas to Bar Harbor, Maine
• Operations with Latin American navies and with visiting European navies
• Development and refinement of fast ship tactics.
• Trial deployments: San Diego to Pearl Harbor (one ship) , Puerto Rico (3 ship detachment) and Grenada (entire squadron) but never deployed out of theater.

PHMs excelled in counter-drug operations and filled a critical mission gap as the US Coast Guard’s WSES surface effect ships did not possess the speed and seakeeping capabilities needed to conduct intercepts of small high-speed boats operated by drug runners. During their operations in the Caribbean Basin, the PHM Squadron (6 ships equating to only 3% of the Navy’s ship count) achieved the following:

• 30% of Navy-assisted “Busts”: 225,000 lbs of marijuana and 12,000 lbs of cocaine seized with a Street Value $1.2 Billion
• 22 USCG Unit Awards and this citation: PHM is: “Superior Platform… the most effective surface asset . .” (in many counter-drug scenarios) COMUSCG District 7 (AUG ‘92)

Despite the remarkable contribution these ships had made to our national objectives, the US Navy decided in June 1992 to decommission them, citing their expense to operate. Since PHM operating costs were very modest – only about 1/3 the cost of an FFG 7, many PHM advocates believe that the six PHMs were sacrificed early in the post-cold war naval drawdown to avoid loss of an equal number of larger, more capable ships. Whatever the motivation, the ships were decommissioned in July 1993 with at least ten years of expected service life remaining. The Navy made no concerted effort to find other utilization for them, and eventually they were sold for scrap. These comments are offered in order to avoid any misconceptions about PHM operational requirements and in-service mission performance.

Mark R. Bebar, Naval Architect
• PHM Project Naval Architect, Naval Ship Engineering Center (NAVSEC), Hyattsville, Maryland (1971 – 1973)
• PHM Production Ship Design Integration Manager, Naval Sea Systems Command (NAVSEA), Arlington, Virginia (1975 – 1979)
• Director, Surface Ship Concepts, Naval Sea Systems Command (NAVSEA 05D1) (1994 – 2003)

President – International Hydrofoil Society (IHS) http://www.foils.org

on Jul 28, 2014

Correction to my previous blog:
Despite the remarkable contribution these ships had made to our national objectives, the US Navy decided to decommission them, citing their expense to operate. Since PHM operating costs were very modest – only about 1/3 the cost of an FFG 7, many PHM advocates believe that the six PHMs were sacrificed early in the post-cold war naval drawdown to avoid loss of an equal number of larger, more capable ships. Whatever the motivation, the ships were decommissioned in July 1993 with at least ten years of expected service life remaining. The Navy made no concerted effort to find other utilization for them, and eventually they were sold for scrap. These comments are offered in order to avoid any misconceptions about PHM operational requirements and in-service mission performance.

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