Boeing 720B 'Pan American' airlines 1/144 Roden 319

Boeing 720B 'Pan American' airlines
1/144 aircraft scale plastic model kit
Roden 319

Manufacturer: Roden (Ukraine)
Scale: 1/144
Material: Plastic
Paint: Unpainted, Unassembled, Kit do not contain paints and glue.
Condition: New in Box

The Boeing 720 was a four-engine narrow-body short- to medium-range passenger jet airliner. Developed by Boeing in the late 1950s from the Boeing 707, the 720 has a shorter fuselage and less range. The 720 first flew in November 1959 and the model entered service with launch customer United Airlines in July 1960.

Two primary versions of the aircraft were built. The original 720 with Pratt & Whitney JT3C turbojet engines entered service in 1960, while the improved 720B with Pratt & Whitney JT3D turbofans entered service in 1961. Some 720s were later converted to 720B specification.

Although only 154 were built, the Boeing 720/720B was still profitable due to the low research and development costs of it being a slightly modified version of the 707-120. It was later replaced by the Boeing 727.

The Boeing 720 is a four-engined low-wing cantilever monoplane. Although it was similar to the Boeing 707, compared with the 707-120 it was 9 ft (2.73 m) shorter in length, and had a lighter structure through use of lighter forged metal parts and thinner fuselage skins and structures.

The rearmost of the 707's over-wing emergency exits was deleted on each side which reduced passenger capacity, while two over-wing exits were an option for higher-density configurations.

The 720 uses an improved wing based on the 707 wing. The wingspan remained the same as the 707-120. For the 720, the wing was changed between the fuselage and inner engines by adding a wing root glove. This glove reduced the drag of the wing by decambering the root, which reduced the "middle effect", thereby increasing the effective local wing sweep. It is reported that the wing root glove increased the drag divergence Mach number of the wing by Mach 0.02.

Though initially fitted with turbojet engines, the dominant engine for the Boeing 720 was the Pratt & Whitney JT3D, a turbofan variant of the JT3C with lower fuel consumption and higher thrust. JT3D-engined 720s had a "B" suffix; some of American's 720Bs were conversions of JT3C-powered 720s.

Like the 707, the 720/720B used engine-driven turbocompressors to supply high-pressure air for pressurization. The engines could not supply sufficient bleed air for this purpose without a serious loss of thrust. The small air inlets are visible just above the main engine inlets on the inner engine pods of all 720s and 720Bs; the lack of the turbocompressor inlets on the outer pods helps spotters distinguish 720/720Bs from most 707s.