The Cessna Citation M2 Engine is the Williams International FJ44-1AP engine. Two FJ44-1AP engines are mounted at the back of the light jet. The Citation M2 specifically uses the FJ44-1AP engine with the part number 72100-201. The previous version of the M2, the CJ1+, used the FJ44-1AP engine with the part number 72100-200. Some call the engine the FJ44-1AP-21 to note the part number difference. Williams International applied for a type certificate for the engine from the Federal Aviation Administration (FAA) on January 28th, 2004. On June 1st, 2005 the company received certification / a type certificate for the engine from the FAA. The jet turbofan engine is produced under FAA Production Certificate 334CE. The Citation CJ1 line has been using the FJ44-1A series engines since the program was started by Cessna in 1992. The FJ44-1AP is similar to the original FJ44-1A engine. The main differences are that the -1AP has a new fan and the low pressure turbine and Dual Channel Full Authority Digital Electronic Control (FADEC) from the FJ44-3A engine have been added to the -1AP.

Williams International FJ44-1AP Engine Photo

Above photo by Cessna. Used under the fair use provision.

Overview on the Engine
The Williams International FJ44-1AP engine is a "Twin spool turbofan with a single-stage fan and single-stage axial compressor direct driven by a two-stage turbine, a single-stage centrifugal compressor driven by a single stage turbine, an annular combustor a full length bypass duct and an exhaust mixer (From FAA Type Certificate for the Engine)."

Williams International FJ44-1AP Engine Photo

Above FJ44-1AP engine photo by Williams International. Used under the fair use provision.

Below is information on the specifications of the engine.

Cessna Citation M2 Engine Specifications FJ44-1AP

Engine Thrust Ratings

  • Maximum Continuous Thrust: 1,950 pounds of force (lbf or just lb) at 59 degrees F
  • Takeoff Thrust: 1,965 pounds of force at 72 degrees F
  • (At sea level, static conditions, flat-rated up to 72° F or 22° C)

One Engine Inoperative (OEI) Operation: The engine may use takeoff thrust for 10 minutes if one engine is inoperative during takeoff.

  • FADEC controlled engines.
  • Time Between Overhaul (TBO): 3,500 hours

Cessna Citation M2 Engine Dimensions – FJ44-1AP Dimensions

  • Length: 57.9 inches or 147.1 centimeters (overall)
  • Height: 31.1 inches or 79 centimeters (overall)
  • Between Flanges: 41.4 inches or 105.2 centimeters

Dry Engine Weight: 468 pounds max

Maximum Interturbine Temperature (ITT)

  • Takeoff for 5 minutes: 1,571 degrees F or 855 degrees C
  • Maximum Continuous: 1,535 degrees F or 835 degrees C

Oil Temperature

  • Maximum: 275 degrees F or 135 degrees C

Oil Pressure

  • Maximum: 120 pounds per square inch (psig) or 130 psig for 5 minutes at or above high pressure rotor N2 speed of 32,960 RPM.
  • Minimum: 23 psig for 5 minutes from idle to high pressure rotor N2 speed of 32,960 RPM.

Engine External Ambient Temperature

  • Maximum: 300 degrees F or 149 degrees C

Maximum Engine Speeds:
Speed Limitations

  • Low Pressure Rotor (N1): 18,055 RPM or 104.69%
  • High Pressure Rotor (N2): 41,200 RPM or 100%

100% Shaft Speed for Reference:

  • 100% Low Pressure Rotor (N1) = 17,245 RPM
  • 100% High Pressure Rotor (N2) = 41,200 RPM