TF41 Spey
An Allison TF41-A-1B turbofan
Type	Turbofan
Manufacturer	Allison Engine Company / Rolls-Royce Limited
First run	1967
Major applications	LTV A-7 Corsair II
Number built	1,440
Developed from	Rolls-Royce Spey

The Allison TF41 (Company designations RB.168-62 and Model 912) is a low-bypass turbofan engine.

Design and development

The TF41 was jointly developed by Allison Engine Company and Rolls-Royce from the latter's RB.168-25R Spey.^[1] Allison manufactured the TF41 under license, while Rolls-Royce supplied parts common to existing Speys.^[2] The TF41 was developed for use in the LTV A-7D Corsair II for the USAF, and the US Navy's A-7E. Between 1968 and 1983, a total of 1,440 TF41s were delivered.^[3]

Applications

• LTV A-7 Corsair II (USAF -D/-K and US Navy -E models),

Specifications (TF41-A-1)

Data from Flight.^[4][5]

General characteristics

• Type: Turbofan
• Length: 114.5 in (2908.3 mm)
• Diameter: 40 in (1016 mm)
• Dry weight: 3,511 lb (1592.6 kg)

Components

• Compressor: Three-stage LP compressor, two-stage IP compressor (both driven by LP turbine),11-stage HP compressor
• Combustors: Cannular combustor with ten flame tubes
• Turbine: Two-stage LP, Two-stage HP

Performance

• Maximum thrust: 14,250 lb (64.5 kN)
• Overall pressure ratio: 20:1
• Bypass ratio: 0.77:1
• Air mass flow: 258 lb/s (117 kg/s)
• Thrust-to-weight ratio: 4.06