GE GEnx-2B67B: The 747-8’s Composite-Fan Turbofan

Quick Answer Summary: The GE GEnx-2B67B is a high-bypass turbofan producing 66,500 lbf takeoff thrust, featuring composite fan blades and powering the Boeing 747-8 and 747-8 Freighter .

The GEnx-2B is the 747-8-specific variant of the GEnx family, distinguished from the 787’s GEnx-1B by its smaller fan diameter (104.7 inches versus 111.1 inches) and different compressor staging. It brings composite fan technology and modern efficiency to the final generation of the 747 .

GEnx-2B67B Specifications

The primary subject of this technical guide focuses on the GE GEnx-2B67B engine, engineered specifically for High-Bypass Turbofan applications. Below is an essential digest of this powertrain configuration.

Key Takeaways & Highlights:
• 66,500 lbf takeoff thrust
• 104.7-inch composite fan
• Powers 747-8
• FADEC III controlled

GEnx-2B67B Technical Data

66,500 lbf takeoff thrust; bypass ratio 8.0 at takeoff; overall pressure ratio 44.7; fan diameter 104.7 inches; 1 fan/3 booster/10 HPC compressor stages; 2 HP/6 LP turbine stages .

The GEnx-2B’s architecture reflects the 747-8’s four-engine configuration: with four engines providing redundancy, each individual engine can be optimized differently than a twin-engine design. The composite fan case and blades reduce weight, and the engine’s 66,500 lbf thrust rating is sufficient for the 747-8’s maximum takeoff weight across four powerplants. Like all GEnx engines, it features FADEC III control and a TAPS combustor for emissions reduction .

Takeoff Thrust 66,500 lbf
Bypass Ratio 8.0 (takeoff) / 7.4 (top-of-climb)
Overall Pressure Ratio 44.7 (takeoff) / 52.4 (top-of-climb)
Fan Diameter 104.7 in
Compressor Stages 1 fan / 3 booster / 10 HPC
Turbine Stages 2 HP / 6 LP
Fuel Jet A / Jet A-1

Aircraft Powered by the GEnx-2B67B

This engine model is deployed across various operational frameworks. Here is a breakdown of the typical machine or vehicle applications using this unit:

Boeing 747-8, Boeing 747-8 Freighter

Pros & Advantages

Composite fan technology; modern efficiency for the 747-8; FADEC III control; TAPS combustor.

Cons & Disadvantages

Lower thrust than GEnx-1B variants; four-engine redundancy reduces per-engine optimization pressure.

Frequently Asked Questions (FAQs)

Q1: What aircraft uses the GEnx-2B67B?

A1: The GEnx-2B67B powers the Boeing 747-8 and 747-8 Freighter .

Q2: How does the GEnx-2B differ from the GEnx-1B?

A2: The -2B has a smaller fan diameter (104.7 in vs 111.1 in), different compressor staging (3 booster stages vs 4), and is optimized for the four-engine 747-8 rather than the twin-engine 787 .

Q3: What is the GEnx-2B67B’s bypass ratio?

A3: 8.0 at takeoff and 7.4 at top-of-climb .


Yes, like all GEnx engines, it features carbon-fiber composite fan blades and fan case .

THE AUTORANK Editorial Note: The GEnx-2B67B gives the 747’s final chapter the most advanced engine the airframe ever carried—a fitting close to a half-century of 747 production.
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