sentences:  The history of "Commercial Aviation" was also covered in a multi-part series starting with the earliest commercial air flights and ending with general aviation and microlights near the very end of the Encyclopedia's run.The second section of the issue was "The World's Greatest Aircraft" and was an in depth look at a major aircraft type, including a cutaway drawing, a list of variants and a three-way view in colour on the centre pages.The North American Mustang was featured in issue one, with the North American XB-70 the final aircraft featured in issue 214.