What Are Leading Edge Slots on Airplanes?


Leading edge slot

Have you heard of leading edge slots? They are commonly found on small and mid-size aircraft. Some airplanes have full-span leading edge slots, whereas others have partial-span leading edge slots. Regardless of the style, they use a similar design that allows for a lower stall speed.

Overview of Leading Edge Slots

Not to be confused with leading edge slots, leading edge slots are slot-like flight surfaces found on the leading edge of an airplane’s wings. They are essentially openings or gaps near the leading edge of the wings. Leading edge slots are parallel to the wings with which they are used. In other words, they run horizontally across the wings.

As previously mentioned, there are full-span leading edge slots, and there are partial-span leading slots. The difference between these two slot types lies in their length. Both slot types consist of gaps, and they are both found on the leading edge of the wings. Full-span leading edge slots run the entire length of the wings with which they are used., whereas partial-span leading slots do not.

The Purpose of Leading Edge Slots

Airplanes can achieve a lower stall speed with leading edge slots. Stall speed, of course, is the minimum speed at which an airplane will produce lift. If an airplane drops below its stall speed, it will fail to produce a sufficient amount of lift. The airplane will then lose altitude until the pilot accelerates and increases the speed to the airplane’s stall speed.

Leading edge slots come at the cost of drag. When compared to airplanes with unslotted wings, those with leading edge slots produce more drag. In turn, they typically consume more fuel as well. But leading edge slots allow for a lower stall speed. Airplanes with leading edge slots can more slowly while still producing a sufficient amount of lift when compared to airplanes with unslotted wings.

Origins of Leading Edge Slots

Leading edge slots have been around for over a century. They were originally developed by British aerospace manufacturer Handley Page in 1919. Since then, leading edge slots have become more common. You can find them on a variety of small and mid-size airplanes.

Keep in mind that leading edge slots aren’t the same as leading edge slats. Sats are retractable control surfaces found on the leading edge of an airplane’s wings. Slots, on the other hand, are slot-like openings found on the leading edge of an airplane’s wings.

Looking to Build Your Own Airplane?

Click below to browse Monroe's Aerospace Parts

Browse Aerospace Parts