Ground Effect

    When discussing aviation there are many outside forces that affect the capability and efficiency of flight. Ground effect is one of these forces, as it can cause disruption in flight. Ground effect normally begins when an aircraft is roughly a wingspan off the ground of closer. This is due to an interruption of airflow patterns around the wing due to the close proximity to land or water. (FAA, 2016) This interruption can cause different issues dependent on what the aircraft is doing. When an aircraft is taking off, ground effect can cause interesting issues with lift. With the reduction of drag and increase of lift due to the disruption of air flow, and aircraft can lift off the ground in the ground effect range before reaching optimal take-off speed. The only problem with this is the aircraft will never leave the range of ground effect, about a wingspan off the ground, until reaching the proper speed. Another issue cause by ground effect occurs when an aircraft is landing. Upon reaching the ground effect range when landing, the disruption of airflow can slow the aircraft’s decent and require a different angle of attack. 

    Though ground effect can cause problems for amateur pilot’s, it’s unique effect on aircraft can also be used to aid flight. It’s been known to aid in soft field take-offs, by lifting the aircraft off the deck early to minimize the surface friction drag caused by the rolling tires on the ground or skis on water. Its effects were also taken advantage off in WWII when bomber pilots lost multiple engines. They realized when flying low to the ocean, with only one engine working, once reaching the ground effect altitude they stopped descending and could continue flying for significant distances.(Estaff, 2015) When understood, ground effect can be used to a pilot’s advantage.

References:

Estaff. (2015, September 25). Using Ground Effect. Retrieved August 23, 2020, from https://www.aviationsafetymagazine.com/features/using-ground-effect-2/

Federal Aviation Administration. (2016). Pilot’s Handbook of Aeronautical Knowledge (PHAK). Retrieved https://www.faa.gov/regulations_policies/handbooks_manuals/aviation/phak/