"I had always realized it was desirable to gear down the jet"

This quote by Frank Whittle is describing the advancement of the jet engine. He is saying that he had always understood that it was important to lower the speed of the jet engine. This is since the jet engine is a complex and effective machine, and it requires to be managed in order to be utilized securely and successfully. By decreasing the speed of the jet engine, it can be utilized more efficiently and securely. This is specifically crucial when the jet engine is being used for business purposes, as it requires to be able to operate at a consistent speed in order to guarantee the safety of passengers and team. By minimizing the speed of the jet engine, it can be utilized better and securely, and this is something that Frank Whittle had actually always know.