ジェット時代 (Jet Age)

What Is the Jet Age?

The jet age describes the period in commercial aviation history — broadly from the mid-1950s onward — when gas-turbine-powered jets displaced propeller aircraft on trunk routes worldwide. Jets offered passengers unprecedented speed and comfort, shrinking journey times dramatically. New York to London, which took 14–17 hours on a Boeing 377 Stratocruiser, fell to under 7 hours on a 707. The cultural impact was profound: international travel ceased to be the preserve of the wealthy and began its democratization into a mass-market activity.

Historical Context

The technological foundations were laid during World War II. Frank Whittle in Britain and Hans von Ohain in Germany independently developed operational jet engines by 1941. The de Havilland Comet entered commercial service with BOAC on May 2, 1952 — the world's first jet airliner — but catastrophic metal fatigue failures grounded it. The Boeing 707 and Douglas DC-8, both certified in 1958, established the jet as the reliable backbone of long-haul aviation. Meanwhile, turboprop engines bridged the gap on shorter routes where pure jets were uneconomical.

Key Milestones

• May 2, 1952: de Havilland Comet inaugurates jet passenger service, London–Johannesburg.
• October 26, 1958: Pan Am Boeing 707 begins first U.S. transatlantic jet service, New York–Paris.
• 1960s: Turbofan engines replace pure turbojets, dramatically cutting fuel burn and noise.
• 1970: Boeing 747 (Jumbo Jet) enters service, doubling passenger capacity and driving down per-seat costs.

Legacy and Impact

The jet age created the modern airline industry. Lower operating costs enabled route expansion and eventually airline deregulation in 1978, which opened the door to low-cost carriers. High-bypass turbofan engines introduced in the 1960s matured into extraordinarily fuel-efficient powerplants. The jet age also reshaped geopolitics, enabling rapid troop and cargo deployment and knitting the world into a single economic system. Today's aviation industry — carrying over 4.5 billion passengers annually before the COVID-19 pandemic — is the direct descendant of the quiet revolution that began when the Comet lifted off from Heathrow in 1952.