Hot and high

The boosters were located adjacent to the main landing gear at the wing root on each side of the aircraft and only intended to operate as an emergency fallback in the case of an engine failure during takeoff.

Such aircraft generally offered the largest wings and/or the most powerful engines in the model lineup coupled with a small fuselage to reduce weight.

Some such aircraft include: The marketing failure of most of these airplanes demonstrated that airlines were generally unwilling to accept reduced efficiency at cruise and smaller ultimate load-carrying capacity in return for a slight performance gain at particular airports.

Rather than accepting these drawbacks, it was easier for airlines to demand the construction of longer runways, operate with smaller loads as conditions dictated, or simply drop the unprofitable destinations.

Furthermore, as the second generation of jet airliners began to appear in the 1970s, some aircraft were designed to eliminate the need for a special "hot and high" variant – for instance, the Airbus A300 can perform a 15/0 takeoff, where the leading edge slats are adjusted to 15 degrees and the flaps kept retracted.