title: Honeywell TPE331
text: The Honeywell TPE331 (military designation: T76) is a turboprop engine. It was designed in the 1950s by Garrett AiResearch, and produced since 1999 by successor Honeywell Aerospace. The engine's power output ranges from .
  
  Design and development
  Garrett AiResearch designed the TPE331 from scratch 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. More than 700 had been shipped by the end of 1973. 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.
  
  Performance
  
  The 715 shp TPE331-6 used in the Beech King Air B100 have 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.
  
  Variants
  
  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)
  
  Applications
  
  Fitted with TPE-331s as a replacement for their original engines
  
  Specifications
  
  See also
  
  References
  
  Bibliography
  
  External links
  
   TPE 331 Cost Protection Programs
   TPE 331 Engine Conversions
   Power and fuel flow versus altitude and speed, for version 10.  (Archive)
  
  1960s turboprop engines
  
  TPE331