Honeywell TPE331

Garrett AiResearch began developing the TPE331 in 1959 for the military. "Designed as a 575-horsepower engine it was not a scaled-down version of a larger engine, as competitors were offering." The TPE331 originated in 1961 as a gas turbine (the "331") to power helicopters. It first went into production in 1963. By the end of 1973, more than 700 units had been shipped. It was designed to be both a turboshaft (TSE331) and a turboprop (TPE331), but the turboshaft version never went into production. The first engine was produced in 1963, installed on the Aero Commander in 1964, and put into production on the Aero Commander Turbo Commander in June 1965.

The 715 shp TPE331-6 used in the Beechcraft King Air B100 has a 400-hr fuel nozzle cleaning interval, 1,800-hr hot section inspection interval, and a 5,400-hr time between overhaul; approval is possible for 3,000-hr HSIs and 6,000-hr overhauls, and engine reserves are cheaper than for the PT6A.

Military variants (T76)

T76-G-2

T76-G-4

T76-G-6

T76-G-8

T76-G-10

T76-G-12

T76-G-12A

T76-G-14

T76-G-16

T76-G-410

T76-G-411

T76-G-416

T76-G-417

T76-G-418

T76-G-419

T76-G-420

T76-G-421

Commercial variants (TPE331)

• Aero/Rockwell Turbo Commander 680/690/840/980/1000
• Antonov An-38
• Ayres Thrush
• BAe Jetstream 31/32
• British Aerospace Jetstream 41
• Beech B100 King Air
• CASA C-212 Aviocar
• Cessna 441 Conquest II
• Comp Air 9
• Conroy Stolifter
• Dornier 228
• Fairchild Swearingen Metroliner
• General Atomics MQ-9 Reaper
• Grob G 520
• HAL HTT-40
• Kestrel K-350
• Mitsubishi MU-2
• North American Rockwell OV-10 Bronco
• Pilatus/Fairchild PC-6C Turbo-Porter
• Piper Cheyenne 400
• Short SC.7 Skyvan
• Short Tucano (EMB-312S Tucano)
• Swearingen Merlin

Fitted with TPE-331s as a replacement for their original engines

• Beechcraft Model 18
• Cessna 208 Caravan
• Cessna 337 Skymaster
• de Havilland Canada DHC-2 Beaver
• de Havilland Canada DHC-3 Otter
• de Havilland DH.104 Dove
• FMA IA 58 Pucará
• Grumman Ag Cat
• Grumman S-2 Tracker
• Marsh S-2F3AT Turbo Tracker
• Handley Page Jetstream
• PAC Fletcher
• SibNIA TVS-2MS (Antonov An-2 conversion)
• Sikorsky H-19 Chickasaw

General characteristics

• Type: Single-shaft turboprop with integral gearbox
• Length: 46 inches (1,200 mm) (TPE331-43A), 42.82 in (1,088 mm) (TPE331-10)
• Diameter: 21 inches (530 mm) (TPE331-43A)
• Dry weight: 336 lb (152 kg) (TPE331-43A), 385 lb (175 kg) (TPE331-10)

Components

• Compressor: Two-stage centrifugal
• Combustors: Reverse annular
• Turbine: Three-stage axial
• Fuel type: Jet A, Jet B, Jet A-1, JP-8, JP-1, JP-4, JP-5, JP8+100

Performance

• Maximum power output: 575 hp (429 kW) (TPE331-43A), 940 hp (700 kW) (TPE331-10)
• Overall pressure ratio: 10.55:1 (TPE331-10)
• Specific fuel consumption: 0.534 lb/(hp⋅h) (325 g/kWh) (TPE331-10)
• Power-to-weight ratio: 1.71 hp/lb (2.81 kW/kg) (TPE331-43A), 2.44 hp/lb (4.01 kW/kg) (TPE331-10)