Green Navy

Last Updated : 12/14/2011 12:00:37 PM

 

PANAMA CITY, Fla. (NNS) -- The Navy successfully
concluded its final alternative fuel demonstration for the year today with the
Dec. 7-9 operational tests of the 50/50 algae-derived, hydro-processed algal oil
and petroleum F-76 blend in a landing craft air cushion (LCAC) amphibious
transport vehicle.
The tests also marked the fastest speed achieved to
date by a U.S. Navy surface craft using alternative fuel blends, as LCAC 91
reached 50 knots, Dec. 7. The fastest speed demonstrated on the 50/50 algal
blend in previous tests was 44.5 knots by the Riverine Command Boat
(experimental) (RCB-X) in October 2010 at Naval Base Norfolk, Va.

"Our
Navy is working to be resilient to any potential energy future. Pursuing
sustainable resources, such as alternative fuels that are drop-in replacements,
assures our performance and mobility while protecting us from the volatility of
the fossil fuel market. This demonstration is another Wright Brothers-moment for
the Navy. We have shown that we can achieve more than 50 knots on the water and
Mach 1.7 in the air - all on biofuel blends," said Rear Adm. Philip Cullom,
director, Chief of Naval Operations Energy and Environmental Readiness Division.

LCACs move elements of a Marine Air/Ground Task Force - weapons systems,
equipment, cargo, and personnel - from ship to shore and over the beach. The
vehicles have four gas turbine engines, and two generators that traditionally
run on NATO F76 or NATO F44. They have a 7,000 gallon fuel capacity, an average
range of 200 nautical miles, and can carry up to 150,000 pounds.

"For
the test, the craft was operated out in the Gulf of Mexico using two different
fuel configurations so we could compare the craft's operations as powered by
each fuel type," said Naval Sea Systems Command's Navy Fuels Engineering Manager
Richard Leung. "After draining the diesel, LCAC 91 received approximately 5,000
gallons of the 50/50 algal blend. We assessed the engine performance
capabilities on the biofuel blend, and collected data on engine torque,
acceleration rates, craft speed, fuel flow rates, propeller pitch, compressor
discharge pressure, and inlet and exhaust gas temperatures"

Mechanical
engineers bore scoped the engines and collected the technical data. LCAC
operators then provided input on how the craft performed and
operated.

"We are going to compare how the engines performed during the
test both on the straight diesel and on the 50/50 mix. Results from the
comparison will help us assess the performance of the fuel," said mechanical
engineer Ben Canilang, NSWC Carderock's Naval Ship Systems Engineering Station,
Philadelphia, Pa.

"To see what type of numbers came out, we connected a
laptop with a harness that read into our digital and analogue data collectors,"
said mechanical engineer Peter Diamond. "The type of analysis is simply
comparing numbers. We'll plug in a stream of numbers and compare results from
each of the tests."

"The test run on the 50/50 alternative fuel mix was
very successful," said Scott Feenstra, mission director, Landing Craft Air
Cushion, NSWC Panama City Division. "LCAC 91 performed without issue. The
operators were able to use high power; and reported that the craft handled
beautifully and without problems."

Meeting the secretary of the Navy's
call for a drop-in fuel replacement, no changes were required to the LCAC or
fueling equipment infrastructures for the test. Alternative fuel efforts also
support the secretary's overall energy strategy to increase energy security and
safeguard the environment; as well as his goals to demonstrate a 'green' strike
group by 2012, and deploy a strike group composed completely of alternatively
powered ships, "The Great Green Fleet," by 2016.