GE Aerospace

CF34-8

Low-Bypass Turbofan In Production

Technical Specifications

Thrust
62,3 kN (14 000 lbf)
Bypass Ratio
5,4:1
Fan Diameter
1,270 m
Pressure Ratio
28,0:1
SFC
0,3400 lb/lbf·h
Dry Weight
1 100 kg
Length
2,860 m
First Run
2001
In Service
2004

Overview

The GE Aerospace CF34-8 is the most-produced variant of the CF34 engine family, powering the second generation of regional jets that grew from 50 seats to 70–90 seats in the late 1990s and 2000s. The CF34-8 powers four aircraft types across two competing manufacturers — Bombardier's CRJ700 and CRJ900, and Embraer's E170 and E175 — making it the defining powerplant of the 70-90 seat regional jet segment.

The CF34-8 is substantially larger than the CF34-3, with a 13 percent wider fan and roughly 50 percent more thrust. Despite this growth, GE preserved the high reliability standards established by the CF34-3, resulting in an engine with dispatch reliability ratings consistently above 99.9% at mature operators.

Technical Specifications

ParameterValue
Thrust62.3 kN (14,000 lbf)
Bypass Ratio5.4:1
Fan Diameter1.270 m (50 in)
Dry Weight1,100 kg (2,425 lb)
Length2.860 m (112.6 in)
SFC0.340 lb/lbf·hr
Pressure Ratio28.0:1
First Run2001
In Service2004

Variants

The CF34-8 family has two sub-series optimized for different airframe manufacturers:

  • CF34-8C5: Developed for Bombardier CRJ700 and CRJ900. Produces 56.4–62.3 kN (12,670–14,000 lbf). The -8C5B1 is the primary production variant for the CRJ900. Features a fan designed for the CRJ's rear-mounted engine nacelle architecture.
  • CF34-8E5: Developed for Embraer E170 and E175. Produces 61.9–62.3 kN (13,900–14,000 lbf). The -8E5 features a slightly different fan and nacelle interface optimized for the E-Jet's under-wing engine installation. Shares over 70% parts commonality with the -8C series, simplifying MRO.

Aircraft Applications

The CF34-8 is the exclusive engine for four regional jet types across two manufacturers:

  • Bombardier CRJ700 — Entered service in 2001 as the first 70-seat CRJ, powered by CF34-8C5. The CRJ700 is a stretched CRJ200 fuselage with new wings, allowing operation under 70-seat scope clause provisions at US mainline carriers. SkyWest and Endeavor Air operate large CRJ700 fleets.
  • Bombardier CRJ900 — A further stretch to 90 seats, entered service in 2003. The CF34-8C5B1 provides additional thrust for the heavier aircraft. American Eagle (now Envoy), Delta Connection operators, and Air Canada Express fly CRJ900s.
  • Embraer E170 — Embraer's 70-80 seat regional jet entered service with LOT Polish Airlines in 2004. The CF34-8E5 is the sole engine option. The E170 features a wider fuselage (2-2 seating) than the CRJ family, offering a notably more comfortable passenger experience.
  • Embraer E175 — The most commercially successful E-Jet first-generation variant, seating 78–88 passengers. The CF34-8E5 powers the vast majority of E175s, which are extensively operated under US scope clause agreements by carriers including SkyWest (United Express, Delta Connection) and Republic Airways.

Development History

GE began the CF34-8 development in the late 1990s, responding to demand from both Bombardier and Embraer for a more powerful derivative to power their competing next-generation regional jets. The decision to create sub-variants for each manufacturer — rather than a single universal engine — allowed GE to optimize the installation for each airframe's specific nacelle geometry and bleed air architecture.

The CF34-8C's first run occurred in 1999, and certification for the CRJ700 followed in 2001. The CF34-8E for the E170 completed its first run in 2001 with service entry in 2004. Both variants rapidly accumulated favorable reliability data, reinforcing the CF34 family's reputation. The simultaneous success on competing platforms from two manufacturers was commercially unprecedented for a regional jet engine program.

With the introduction of the E-Jet E2 family powered by Pratt & Whitney PW1900G GTF engines, new production of the CF34-8E has substantially declined. However, the enormous installed base of E175 and CRJ900 aircraft — over 1,400 aircraft combined — ensures a robust aftermarket for CF34-8 MRO services through the 2040s.