Last month the US Navy successfully operated an LCAC craft on a 50/50 mix of algae based fuel and conventional marine diesel. And just to ensure that folks were paying attention, they went and broke a speed record as well. The LCAC is powered by Vericor ETF40B engines and this was the first operation of a Vericor marine gas turbine on an algae fuel mix as well. Sanjay Hingorani, Vericor VP of Engineering, said "the engines performed as we expected, with no operational problems and no degradation in performance." He added: "The Navy has done their homework and this fuel type holds a lot of promise for the future."
The LCAC is powered by four Vericor ETF40B engines driving the craft's lift fans and propulsion fans. It carries up to 75 tons of cargo over a beach, delivering vehicles or materiel from ships over the horizon to dry land, a job no other piece of machinery can do. This particular test was the first for Navy gas turbines operating on bio fuel in a field application. They knew that the ETF40B would be an ideal test bed as the LCAC craft could execute a comprehensive test program in a short period of time and data could be collected on four engines at once.
To do an accurate assessment of the new fuel the Navy conducted essentially a back to back test at its Panama City base, home of the LCAC test operations. The workhorse LCAC test craft, number 91, was fueled with conventional F-76 spec marine diesel and put through its paces. Before and after the test all four of the engines were inspected by borescope. Then the craft was re-fueled with the algal blend and the same test program executed. The craft performed flawlessly.
The US Navy reported that data was collected on engine torque, acceleration rates, craft speed, fuel flow rates, propeller pitch, compressor discharge pressure and inlet and exhaust gas temperature. When the engines were re-examined after the test they were found to be even cleaner than with the straight marine diesel. Navy officials were impressed with the results.
The craft hit the fastest speed recorded for the fuel for a US surface craft, topping 50 kts, and that was with a full payload. Pretty impressive for a first time out and a sure sign of the possibilities that this new fuel presents to the US Navy.