Three shafts and a distinctive note

Rolls-Royce's RB211-524 brought the three-shaft gas generator to the 747, delivering smooth, efficient power and a distinctive high-pitched note that became part of the classic 747 sound.

Key facts
Applications	747-200, -200B, -200F, 747SP, -300 (-524B/C/D4); 747-400 and -400ER (-524G/-524H only)
Thrust classes	B2 49,120 lbf; C2 50,600 lbf; D4 53,000 lbf; G 58,000 lbf; H 60,600 lbf
Bypass / fan	5.0:1 (B/C/D4), 4.3:1 (G/H); 86.3 in fan
First customer	British Airways - ordered June 1975, entered service June 1977 on a 747-200B

British Airways ordered the RB211-524 for its 747-200Bs in June 1975 and introduced it in service in June 1977. Qantas then had Boeing adopt the higher-thrust -524D4 on its 747-238Bs from 1979, and SAA, Cathay Pacific and others followed on -200s and -300s.

The -524 was never fitted to the 747-100 or the 747-8. Its final 747 application was the -524G (58,000 lbf) and -524H (60,600 lbf) - the first FADEC-equipped RB211s - which entered service with the 747-400's FAA certification in January 1989. The heavier H/T version served the 747-400ER.

Later hybrid -524G/H builds paired the RB211 core work with technology from the Trent family, extending the engine's life right up to the end of 747 passenger operations.

Three shafts, distinctive sound

The RB211-524 brought Rolls-Royce's three-shaft gas-generator architecture to the 747, and with it a smooth, efficient power delivery and a distinctive high-pitched note that became part of the classic 747's sound. The three-shaft layout - separate gas generator and fan spools - was the RB211's signature, and it gave the engine a balance and response the two-shaft competitors of its day did not quite match.

British Airways first, then the world

British Airways ordered the RB211-524 for its 747-200Bs in June 1975 and introduced it into service in June 1977, making it the first Western customer of a Rolls-Royce engine on a 747. Qantas then had Boeing adopt the higher-thrust -524D4 on its 747-238Bs from 1979, and South African Airways, Cathay Pacific and others followed on the -200 and -300. The -524 was never fitted to the 747-100 or the 747-8.

The -400 and -400ER return

After a gap through the early -400 development, the RB211 came back in force as the -524G and -524H - the first FADEC-equipped RB211s - which entered service with the 747-400's January 1989 certification. The -524G at 58,000 lb powered the -400, and the heavier -524H (with the later -524H8-T and -524H8-T variants) served the 747-400ER. Later hybrid -524G/H builds paired the RB211 core with technology from the Trent family, extending the engine's life to the very end of 747 passenger operations. It remains the only British engine ever to power a 747.

Related

• Fuel system
• Hydraulic systems
• Electrical system
• 747-8 systems differences