The development of Airbus as a company and the A300 as an airplane was fraught with challenges.
First, there was the issue of engines. Airbus struggled to find a suitable engine for the plane. Rolls-Royce's new RB211 triple-spool turbofan engine was expected to be able to deliver the performance capable of powering the new 300 seat jet. So Airbus planned to use a version of the Rolls-Royce engine called the RB207. But, that deal fell through, leaving the A300 with no engines.
Instead, Airbus decided to buy off-the-shelf engines from GE and Pratt & Whitney after it scaled the A300 down from 300 seats to 250 seats. This occurred after Airbus realized that its plane may be too big for the European market due to lower airline demand forecasts.
In late 1968, the structure of the consortium took a major shift when the British government decided to pull its support in the wake of the massive cost overruns associated with the Concorde program. But, British manufacturer Hawker Siddeley remained in the consortium to build the A300's wings.
On December 18, 1970, Airbus Industrie was officially created.