A Good Reason For Flight III Burkes

As discussed in two CRS reports (CRS Report RL33360 and CRS Report RS22595), one maker of electric-drive propulsion equipment has proposed increasing the planned scope of the Navy’s program for modernizing its DDG-51s to include adding some electric-drive propulsion equipment to the ships’ existing mechanical-drive propulsion plants. The option could also be applied to new-construction DDG-51s. The added equipment would more fully interconnect the mechanical-drive components on each ship, producing what the firm refers to as a hybrid propulsion plant. The firm estimates that the addition of this equipment would reduce DDG-51fuel use by about 16%. This option, the firm estimates, would have a non-recurring engineering cost of $17.1 million and a recurring cost (including both equipment cost and installation cost) of $8.8 million per ship.

Using the figures in the table from Admiral Roughead’s May 7 letter, reducing DDG-51 fuel use by 16% would reduce the ship’s annual operating (steaming) cost from the figure of $15.7 million shown in the table to about $13.2 million—a reduction of about $2.5 million. The Navy has informed CRS that the operating (steaming) cost figures in the May 7 letter are based on fuel costs as of February 2008 and reflect a fuel cost of $112.14 per barrel. If fuel in coming years costs more than $112.14 per barrel, the dollar savings associated with a 3.9% reduction in fuel use would be greater than $2.5 million per year. The obverse would be true if fuel in coming years costs less than $112.14 per barrel.

Navy DDG-1000 and DDG-51 Destroyer Programs: Background, Oversight Issues, and Options for Congress, Ronald O'Rourke, April 13, 2024

Ronald O'Rourke's report footnotes that the firm providing him with data is DRS Technologies. I think that is an important detail. Ever since the Navy truncated the DDG-1000 in favor of the DDG-51, I have been consistently critical of the move. In testimony the Navy has consistently claimed that Flight IIA versions of the Arleigh Burke class destroyer would be built beginning in FY2010 (this year). As much as I like the Burke, and I love the Burke, I don't feel very good about moving backward when it is unclear how to move the Burke forward.

When Ronald O'Rourke presented his options for additional technologies possible for the Arleigh Burke class, options that remain in the report linked above, the Navy left no indication at all that they were even considering new technologies for the Burke. For me, that was a troubling sign. It is peacetime and we enjoy a lead in surface combatant superiority, now is the time to experiment with new technologies, not get complacent with what we have. From a historical view, I look at how the US Navy built the Pensacola class, followed by the Northampton class, then the Portland and Brooklyn classes, all of which built during restriction period governed by the Washington Treaty. These cruisers were in fact steady state evolutions towards what became the brilliant Baltimore class cruisers that served in the Pacific from 1943-1945.

When I look at the Burke, my primary concern is that by sticking with the Flight IIA, the Burke gives the impression there isn't much room left for growth. Until last week, there has been very little evidence the Navy has been looking into new technologies beyond the modernization to the Advanced Capability Build 12 baseline. Then we got this contract last Wednesday.

General Atomics, San Diego, Calif., is being awarded a $32,727,170 not to exceed, cost-plus-fixed-fee contract for development of a prototype hybrid electric drive (HED) system for a full-scale demonstration. HED is aimed at improving the operating efficiency of the engineering plant on DDG 51 Class Ships and is intended to demonstrate the capability for significant fuel savings by incorporating advanced electric machine technology. This supports the national defense imperative to reduce dependence on foreign non-renewable energy resources. Work will be performed in San Diego, Calif., (50 percent); Milwaukee, Wis., (24 percent), and Hudson, Mass., (26 percent), and is expected to be completed by June 2014. Contract funds will not expire at the end of the current fiscal year. This contract was competitively procured under a Broad Agency Announcement, with 23 offers received. The Naval Sea Systems Command, Washington Navy Yard, D.C., is the contracting activity (N00024-09-C-4222).

According to the press release on General Atomics website, partial funding comes from the American Recovery and Reinvestment Act of 2009, the gigantic economic stimulus package from January. The contract is for a proof-of-concept Hybrid Electric Drive (HED) system and includes installation on an existing DDG-51. According to the General Atomics website, "HED will improve the operating efficiency of the engineering plant on DDG 51 Class Ships and is intended to provide the capability for significant fuel savings, up to 12,000 barrels of fuel per year, per ship, by incorporating advanced electric machine technology." The press release goes on to list DRS Technologies as a partner for the contract, sort of making it sound like this is the information Ronald O'Rourke was discussing in his report.

Bruce V. Bigelow has a report on Xconomy that includes an interview with Carl Fisher, who heads business development at General Atomics’ Electromagnetic Systems Division.

The destroyers are powered by four General Electric gas turbines capable of powering the ship at speeds in excess of 30 knots (about 35 mph). GA’s concept would basically convert the Navy’s modern man of war into a hybrid-electric Prius of the seas.

“Obviously, there are differences,” Fisher says, “but the analogy is consistent.” According to the GA executive, the Navy contract calls for integrating a prototype electric motor with the warship’s reduction gears, enabling the destroyer to use its electric motor for low-speed operations below 10 or 12 knots (about 14 mph).

It is noteworthy this contract comes about a month after GE Marine won ONR's DDG 51 Fuel Efficient and Power Dense Demonstrator competition, described as follows by GE Marine's press statement on the contract.

"This project will develop and demonstrate the technology necessary to enable substantial annual fuel savings by cross-connecting the currently independent main propulsion system and the ship service electrical system, creating a hybrid mechanical “electric drive power plant," said GE Marine's General Manager, Brien Bolsinger, Evendale, Ohio. "The system modifications proposed by GE have the potential to increase ship service electric power capacity, improve power quality and add redundancy," Bolsinger added.

Currently the DDG 51 main propulsion and ship service configuration consists of four GE LM2500 aeroderivative gas turbines and three ship service turbine-generators, with four engines on line during the majority of underway operations. GE will demonstrate that the modified system will save fuel by meeting all the ship power requirements at low and moderate speeds with a reduced quantity of gas turbines operating. GE expects a better match between the power available and the load, allowing the gas turbines to operate more efficiently.

I am beginning to suspect that power optimization, more than any other specific capability, is the next major technology evolution for warships, and both of these contracts reflect a sea change in what will be possible out of ships in the future. This doesn't just go for existing DDG-51s or new DDG-1000s, but can be applied across the board to new warships both big and small. The long term consequence will hopefully lead to more fuel efficiency, thus endurance potential, for small ships as well.

It is fantastic to see this type of technology refit being applied to the DDG-51s, because while fuel savings are an obvious cost-saving benefit, the real capability increase here is the increase capability of the Burke to distribute more power to the ships combat systems. There are other advantages as well, because just having the option to turn off turbines when drifting with a tail allows for a ships Captain to reduce the ships noise output, for example. These little things can add up.

If these technologies work out, and there are good reasons to believe they will, the Burke can now support much better radar systems, new gun systems, and easily support the extra power requirements for emerging laser systems previously thought to be options only for the DDG-1000.

I may be mistaken, but I believe ONR's DDG 51 Fuel Efficient and Power Dense Demonstrator competition was specific to Flight IIA only, although I am not sure why it would not scale to previous variants of theDDG-51. With an understanding these technologies are for backfitting purposes, I don't see why they shouldn't be included in any new orders for Arleigh Burke destroyers.

In fact, if we are going to buy new DDG-51s, a good reason to build an Arleigh Burke destroyer that makes sense to me is if we are buying an evolved model (Flight III), with some specific enhancement with a vision looking forward. In my opinion, building new Burkes with the intention of upgrading power technologies is a business case much easier to sell to the American taxpaying public. After all, these type of technologies in energy efficiency do have trickle down effects, for example, the LM2500 gas turbine is part of GE's CF6 family of commercial airline turbine engines, the same CF6 family of turbines used on DC-10, MD-11, A300, 747 and 767 aircraft.

While it may sound strange today, it is entirely possible these investments by the Navy end up making commercial airline travel cheaper for the regular folks in 2020.