747-100B
The 747-100B was a strengthened, higher-weight 747-100 delivered to just two customers.
The 747-100B was a strengthened 747-100: a stronger airframe and undercarriage, and a maximum takeoff weight raised to 750,000 lb (340,000 kg). It is one of the rarest 747 variants ever sold, and one of the least visible — nothing about it looks different from the outside.
Only nine were built: one for Iran Air and eight for Saudia, now Saudi Arabian Airlines.
Why so few
By the time the -100B was on offer, Boeing had already launched the 747-200, which did the same job better. The -200B had more fuel, higher weights again, and a wider choice of engines. An airline that wanted a heavier 747 generally bought a -200 rather than a strengthened -100, and the -100B survived as a niche for two customers who wanted -100 commonality with more margin.
Engines
Rolls-Royce (RB211) and General Electric (CF6) were both offered alongside the Pratt & Whitney JT9D. Only Saudia took the Rolls-Royce option — which makes the Saudia -100Bs among the very few RB211-powered aircraft of the first 747 generation.
The other -100B
The designation also appears attached to Japan’s domestic aircraft, as the 747-100B/SR — a short-range, high-density airframe built on the strengthened -100B structure. Two of those were delivered to Japan Airlines with a stretched upper deck, an arrangement covered on the 747-100SR page.
Read more about the base aircraft on the 747-100 page, or about where the extra weight capability eventually led on the 747-200 page.
| Manufacturer | Boeing |
|---|---|
| Variant | 747-100B |
| Max takeoff weight | 750,000 lb (340,000 kg) |
| Number built | 9 |
Video
More in Boeing 747 Family
Boeing 747 Family
Every Boeing 747 variant built between 1968 and 2023 — the 747-100, -200, -300, -400 and 747-8, with freighter, combi and short-range models explained.
747-100
The original Boeing 747-100 entered service in 1970 with six upper-deck windows and a lounge; later aircraft offered a ten-window upper deck.
747-100F
Freighter specification for the Boeing 747-100F, covering main-deck and belly cargo volumes, pallet counts and upper-deck crew lounge options.
747-100SR
Built for Japanese domestic routes, the 747-100SR traded fuel capacity for seats, carrying up to 550 passengers on short high-frequency sectors.
747-100SP
The shortened 747SP was built for Pan Am and Iran Air to fly ultra-long routes such as Tehran-New York, then the longest nonstop service.
747-200
The 747-200 brought more powerful engines, higher takeoff weights and greater range than the -100, and spawned freighter, combi and convertible models.
