In June, the Cessna Aircraft Company delivered its first new Citation X+ jet, reclaiming its position as the producer of the world’s fastest civil aircraft. It had lost that distinction to Gulfstream in late 2012, with the debut of the G650. The Citation X+ can reach a speed of Mach 0.935 (617 mph at cruising altitude), just beating the G650’s Mach 0.925 (602 mph).

The X+ offers a bigger cabin than its predecessor, with an extra 15 inches in length, providing more legroom for passengers in the forward club …