Allison T56

The Allison T56 is an American single-shaft, modular design military turboprop with a 14-stage axial flow compressor driven by a four-stage turbine.The Series I collection of derivatives came out in 1954, producing a sea-level static power rating of 3,460 propeller shp (2,580 kW) at a 59 °F (15 °C; 519 °R; 288 K) ambient temperature.[11] The T56 Series 3.5, an engine enhancement program to reduce fuel consumption and decrease temperatures, was approved in 2013 for the National Oceanic and Atmospheric Administration (NOAA) WP-3D "Hurricane Hunter" aircraft.Naval Air Systems Command (NAVAIR) order in 2019 of 24 additional E-2D Advanced Hawkeyes (AHEs) powered by the T56-A-427A engine variant.[28]: 3 Following the HLH program cancellation, Allison decided in early 1976 to apply the XT701 engine technology into a new industrial gas turbine product, the 570-K.The industrial engine, which entered production in the late 1970s, was derated to 7,170 shp (5,350 kW) and adapted for marine, gas compressor, and electrical power generation variants.The 570-K was then adapted to the 6,000 shp (4,500 kW) 501-M78B demonstration engine, which Lockheed flew on a Grumman Gulfstream II as part of the NASA Propfan Test Assessment Program in the late 1980s.Further derivatives of the 501-D/T56 were produced as turboshafts for helicopters including a variant designated T701 that was developed for the canceled Boeing Vertol XCH-62 project.
Allison T56-A1 turboprop engine cutaway, at the Smithsonian National Air and Space Museum
TurbopropUnited StatesAllison Engine CompanyRolls-Royce plcConvair 580Grumman C-2 GreyhoundLockheed C-130 HerculesLockheed L-188 ElectraLockheed P-3 OrionNorthrop Grumman E-2 HawkeyeLockheed CP-140 AuroraAllison T38Rolls-Royce T406compressorRolls-Roycemilitary transport aircraftmaritime patrol aircraftGrumman E-2 Hawkeyeairborne early warningcarrier onboard deliveryLockheed ElectraUnited States CongressU.S. Air ForceNAVAIRLockheed L-100turboshaftNAVSEAtorqueLockheed Martin C-130J Super HerculesRolls-Royce AE 2100scimitar propellersDowty RotolAE 1107CUTC Aerospace SystemsNaval Air Systems Commandflight testsboundary layer controlshort takeoff and landingU.S. Armyaeroderivativenatural gasTiconderoga classArleigh Burke classBoeing VertolGeneral MotorsXCH-62overall pressure ratioannular combustorbleed airGrumman Gulfstream IIHamilton StandardpropfanAllison T56 variantsturboshaftshelicoptersBoeing Vertol XCH-62Aero Spacelines Super GuppyBoeing 929Convair 580 and Convair 5800Lockheed L-100 HerculesPiasecki YH-16B Transporterengineaxial flowCombustorscylindrical flow-throughTurbineKerosenejet fuelaviation gasolineSpecific fuel consumptionPower-to-weight ratioshp/lbAllison T40Allison T78Rolls-Royce AE 3007Bristol ProteusIvchenko AI-20Lycoming T55Napier ElandRolls-Royce TyneList of aircraft enginesFlightSmithsonian National Air and Space MuseumFlightGlobalAINonlineAmerican Institute of Aeronautics and AstronauticsAviation Week and Space TechnologySociety of Automotive EngineersFederal Aviation AdministrationU.S. Department of TransportationAviation Week & Space TechnologyAviation Weekaircraft enginesV enginesVG-1410V-1710V-3420TurbojetsTurbofansAE 3007AR.168RTurboprops250/T63AE 2100variants578-DXRolls-Royce Holdingsaero enginesSpey JuniorTrent seriesTrent 500Trent 700Trent 800Trent 900Trent 1000Trent XWBTrent 7000MTR390RB2011RB3011LiftSystemgas turbinesAllisonRolls-Royce Heritage TrustUnited States militarydesignation systemLHTEC T800APW T800Adaptive cycle enginesUnited States Air ForceA/B/E/F/NL (II)A/B (I)S (II)