Allison T56 engine

Rolls-Royce has received a modification contract for repair and upgrade of T56 engines, installed on US Navy aircraft.

Under the $35m deal, which follows a previously awarded contract, Rolls-Royce will provide depot-level repair of the T56 Series III engine modules in support of deployed Lockheed Martin P-3 Orion anti-submarine warfare aircraft.

The contract will also support P-3-based aircraft and the T56 engine-powered Lockheed C-130 Hercules and Northrop Grumman C-2A Greyhound aircraft.

Rolls-Royce Defence customer services president Paul Craig said that work under the new option year for a long-term contract to repair and overhaul engines for US Navy aircraft would be performed at Rolls-Royce Engine Services in Oakland, US.

"This services facility is a key part of our overall support network for military customers as we seek innovative and cost-effective ways to ensure their missions can be completed," Craig said.

Comprising can-annular type combustor and the accessory drive housing, the T56 single shaft turboprop engine features a 14-stage axial flow compressor driven by a four-stage turbine unit.

"This services facility is a key part of our overall support network for military customers as we seek innovative and cost-effective ways to ensure their missions can be completed."

The T56 engine also powers a wide variety of propeller-driven aircraft such as Lockheed Martin-developed C-130A-H Hercules aircraft and Northrop Grumman-built E-2 Hawkeye early warning aircraft.

The Rolls-Royce Engine Services Oakland (RRESO), US, also provides services to other military customers for AE 1107C, F405 and M250 engines.

To date, the company has delivered more than 18,000 T56 military turboprop and its commercial version, the 501-D turboprops, since the engine entered production in 1954.

A full authority digital engine control (FADEC) and monitoring system for the series IV engine is being developed by Rolls-Royce to reduce pilot work load while enhancing maintainability for the US navy’s E-2C Advanced Hawkeye.


Image: A Lockheed-built C-130H Hercules aircraft equipped with Allison T56 engine. Photo: courtesy of US Air Force, by master Sgt Ken Stephens.

Defence Technology