Lycoming IO-720


The Lycoming IO-720 engine is a large displacement, horizontally opposed, eight-cylinder aircraft engine featuring four cylinders per side, manufactured by Lycoming Engines.
There is no carbureted version of the engine, which would have been designated O-720 and therefore the base model is the IO-720. The IO-720 is the only flat-eight configuration aircraft engine currently in production.

Design and development

The engine has a fuel injection system which schedules fuel flow proportionally to the airflow, with fuel vaporization occurring at the intake ports. The engine has a displacement of 722 cubic inches and produces. The cylinders have air-cooled heads cast from aluminum alloy with a fully machined combustion chamber.
The first IO-720 was type certified on 25 October 1961 to the CAR 13 standard as amended to 15 June 1956 including 13-1, 13-2, 13-3, 13-4.
In 2009 a new IO-720-A1B cost US$113,621, with a rebuilt engine retailing for US$75,435 and a factory overhaul priced at US$66,289.

Variants

;IO-720-A1A
;IO-720-A1B
;IO-720-A1BD
;IO-720-B1A
;IO-720-B1B
;IO-720-B1BD
;IO-720-C1B
;IO-720-C1BD
;IO-720-D1B
;IO-720-D1BD
;IO-720-D1C
;IO-720-D1CD

Applications

;IO-720-A1A
  • Northwest Ranger - factory installation
  • Piper Comanche 400 - factory installation
;IO-720-A1B
  • Beechcraft 80 - Excalibur and Queen Air conversions
  • Helio Courier - Helio Courier H-800 factory installation
  • Pacific Aerospace FU-24-954
  • Piper PA-36 Pawnee Brave - Johnson Aircraft conversion
;IO-720-A1BD
  • Barr 6
;IO-720-B1A
  • Northwest Ranger C-6 - factory installation
;IO-720-B1B
;IO-720-B1BD
  • Aero Commander - MR. R.P.M. conversion
;IO-720-D1B
;IO-720-D1C
  • Piper PA-36 Pawnee Brave - Johnson Aircraft conversion
;IO-720-D1CD
  • Piper PA-36 Pawnee Brave - Johnson Aircraft conversion

    Specifications (IO-720A)