Avro Lancaster B.I
Avro · United Kingdom · first flew 1941 · bomber
The Lancaster B.I was the initial production variant, powered by Rolls-Royce Merlin XX engines and forming the backbone of Bomber Command's night offensive from 1942.
Recognition (WEFT)
| W — Wings | Mid-mounted, tapered |
|---|---|
| E — Engines | 4 × piston, wing-mounted |
| F — Fuselage | Ventral dustbin turret sometimes fitted in early examples; later deleted leaving a smooth belly under mid-fuselage |
| T — Tail | Twin fin |
WEFT is AircraftIQ's four-point recognition method — how it works.
Spot it by:
- Rolls-Royce Merlin XX/22/24 engines in individual nacelles — no extended chin or bulge under cowlings
- Ventral dustbin turret sometimes fitted in early examples; later deleted leaving a smooth belly under mid-fuselage
- Visually almost identical to B.III; distinguish by ovoid nacelle profile rather than flat-sided Packard Merlin nacelles
Against the B.III, the B.I has Rolls-Royce Merlin nacelles with a slightly more rounded cowling profile; both marks share identical fuselage and tail geometry, making mark identification difficult at distance.
Specifications
- The Avro Lancaster B.I has a length of 21.2 m (70 ft).
- It has a wingspan of 31.1 m (102 ft).
- Its maximum speed is 462 km/h (287 mph).
- Typical crew: 7.
Figures are for the representative variant described above; marks differ. See how AircraftIQ sources figures.
History
First deliveries reached No. 44 Squadron in late 1941. The B.I quickly standardised the Lancaster's layout of four Merlins, twin-oval tail fins, and a capacious bomb bay capable of carrying the 22,000 lb Grand Slam. It served alongside the B.III throughout the war, the two marks being interchangeable on the production line.
Variants
The B.I(Special) was modified for extra-large bombs such as Tallboy and Grand Slam, with the mid-upper turret removed to save weight.
Where you'll see it
The Battle of Britain Memorial Flight's PA474 is a B.I(FE) airframe and remains airworthy at RAF Coningsby; many B.I airframes are preserved at the RAF Museum Hendon and Imperial War Museum Duxford.
Related aircraft
- Avro Lancaster
- Avro Lancaster B.III
- Avro York
- Avro Manchester
- Boeing B-17E Flying Fortress
- Commonwealth Aircraft Corporation Woomera
- Consolidated TBY Sea Wolf
- de Havilland Mosquito B.IV
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