CF34-3

Overview

The GE Aerospace CF34-3 is the engine that launched the modern regional jet era. A derivative of the military TF34 turbofan developed for the Fairchild Republic A-10 Thunderbolt II attack aircraft, the CF34-3 was adapted for commercial service on the Bombardier CRJ100 and CRJ200, transforming what had been a corporate jet (the Canadair Challenger 600) into a regional airliner. Over 3,500 CF34-3 engines were delivered, and the type remains in active service across the global regional airline network.

The CF34-3 is technically classified as a high-bypass turbofan by its 6.2:1 bypass ratio, but it occupies the lower end of the commercial bypass ratio spectrum and is operationally grouped with regional jet powerplants. Its compact dimensions, light weight, and outstanding time-between-overhaul performance made it the dominant engine in the 50-seat regional jet segment for more than two decades.

Technical Specifications

Variants

The CF34-3 family has two main production variants for the CRJ platform:

• CF34-3A1: Baseline variant producing 38.8 kN (8,729 lbf), certificated in 1992 for the CRJ100. The -3A1 was the initial production configuration and established the engine's high reliability reputation.
• CF34-3B1: Growth variant producing 41.0 kN (9,220 lbf) for the CRJ200 and high-gross-weight CRJ100ER variants. Provides improved hot-and-high performance and slightly better fuel burn through refinements to the combustion system and turbine cooling.

Aircraft Applications

The CF34-3 powers one of the most numerous regional jets in service:

• Bombardier CRJ200 — The CRJ200 is a stretched, re-engined derivative of the CRJ100, with CF34-3B1 engines offering improved efficiency over the -3A1 of the earlier model. The CRJ100/200 family sold over 1,000 aircraft and became the dominant 50-seat regional jet in North America, operated under scope clause agreements at major carriers including American Eagle, Delta Connection, United Express, and US Airways Express. Despite being out of production since 2006, a large fleet remains in service, particularly at SkyWest Airlines.

Development History

The TF34 military engine first flew in 1972 and was selected to power the A-10 Warthog, entering service in 1977. General Electric recognized the commercial potential of the engine's efficient and reliable architecture, beginning the CF34 commercial derivative program in the late 1970s. The designation CF34 identifies it as a commercial ("C") fan engine ("F") in the 34 product family.

Bombardier (then Canadair) selected the CF34-3 for the new regional jet variant of the Challenger 600 airframe in the mid-1980s, giving the engine its crucial launch customer. The CRJ100 completed its maiden flight in May 1991 and entered revenue service with Lufthansa CityLine in 1992. The combination of the CRJ airframe and CF34 engine proved immediately successful, and the program triggered a regional jet revolution as US airline deregulation and scope clause agreements created enormous demand for 50-seat jets.

The CF34-3's military heritage contributed to its exceptional reliability. Dispatch reliability exceeded 99.9% at mature operators, and time-between-overhaul stretched to over 20,000 hours for well-maintained engines. This performance record gave GE the credibility to develop the enlarged CF34-8 and CF34-10 variants for the next generation of regional jets.