The Game Changer: The "Glass Cockpit"

The single most important difference between the 747-400 and all its predecessors (-100, -200, -300, SP) was the cockpit.

Boeing completely eliminated the hundreds of analog dials and steam gauges that defined earlier cockpits. They were replaced with a "glass cockpit" featuring six large CRT (later LCD) digital screens showing flight instruments, navigation, and engine data.

The Consequence: The Two-Person Crew
Because digital computers now monitored the aircraft's systems automatically, the position of the Flight Engineer was permanently eliminated.

The 747-400 was flown by only two pilots (Captain and First Officer). This generated massive salary savings for airlines and was the primary reason the -400 became such a huge commercial success while the -300 failed.

Distinctive Visual Features

The 747-400 is relatively easy to distinguish from earlier models if you know what to look for.

1. Winglets

The most obvious spotting feature of the standard 747-400 is the presence of winglets—the 6-foot tall, angled upward tips at the end of the wings. These were added to reduce drag and improve fuel efficiency by roughly 4%.

2. The Stretched Upper Deck

Like the -300, the -400 features the long, stretched upper deck hump that runs almost to the back of the wings. It also utilizes the straight internal staircase introduced on the -300.

3. Engines

The engines on the -400 (improved Rolls-Royce RB211, GE CF6, or Pratt & Whitney PW4000) appear sleeker and have fewer visible vents on the cowlings compared to the engines on -200s or -300s.

Performance and Capabilities

The 747-400 was a powerhouse that unlocked true global connectivity.

• Range: Thanks to the winglets, efficient engines, and an additional fuel tank in the horizontal tail, range increased to over 7,200 nautical miles (13,400 km). It could easily handle routes like London to Singapore or Los Angeles to Sydney non-stop with heavy payloads, routes that stretched earlier models to their limits.
• Speed: It was faster than its predecessors, with a typical cruise speed of Mach 0.855.

Key Variants

Because it was so successful (nearly 700 were built), the -400 saw several variations:

• 747-400 (Passenger): The standard intercontinental passenger version.
• 747-400F (Freighter): A hugely successful factory-built cargo version with the hinged nose door. It has the short upper deck hump of the classic models (to save weight) but the winglets and modern cockpit of the -400. These remain the backbone of global air cargo today.
• 747-400M (Combi): Passenger/freight mix on the main deck.
• 747-400D (Domestic): A specialized high-density Japanese version (like the old 747SR). It could carry over 560 passengers. Crucially, it did not have winglets, as they were unnecessary for short hops and added weight.