How did the Avro 707B differ from the 707A?

Short answer

In the flight regime they studied. The Avro 707B, the second low-speed example, investigated delta-wing handling at low speeds; the 707A was designed as a high-speed variant in place of the cancelled Avro 710. The 707B flew in September 1950 and the 707A in July 1951.

Published: October 22, 2026 · Updated: October 22, 2026 · Edited by Above Ten Thousand · Editorial policy

How did the Avro 707B differ from the 707A?

Avro 707A WZ736 MSIM 10 08 85R edited 2RuthAS (CC BY), vía commons

Two extremes of the same wing

Avro had no experience flying delta wings when it embarked on the 698 bomber project. It therefore planned two smaller experimental aircraft: the 707, at one-third scale, to study low-speed behaviour, and the 710, at half scale, for high speed. When the 710 was cancelled as too slow to develop, Avro designed a fast variant of the 707 itself instead: the 707A.

The 707B, the slow one

The first 707, VX784, flew in September 1949 and crashed that same month. The second, low-speed example, VX790, was built with the nose section of the still-unfinished 707A, which included an ejector seat, and was therefore redesignated 707B. It flew in September 1950, piloted by Avro test pilot Roland "Roly" Falk, the same pilot who would later bring the Vulcan to fame.

The 707A, the fast one

The high-speed 707A, registered WD280, flew in July 1951. While the 707B explored the lower part of the flight envelope, the 707A was intended for the upper part. Because of the programme's delay, the contribution of both aircraft to the basic design of the 698 was not considered significant, although they did highlight some necessary changes.

Their real merit lay elsewhere: the 707B and the 707A proved the validity of the design and gave confidence in the delta planform. A second 707A, WZ736, and a two-seat 707C, WZ744, were built afterwards, but they no longer took part in the Vulcan's development.

The aircraft was born from Air Ministry specification B.35/46. The first prototype flew on 30 August 1952, and the RAF received its first Vulcan B.1 in September 1956.