Jet blast

Jet blast is the phenomenon of rapid air movement produced by the jet engines of aircraft, particularly on or before takeoff. A large jet-engine aircraft can produce winds of up to 100 kn as far away as 60 m behind it at 40% maximum rated power. Jet blast can be a hazard to people or other unsecured objects, and can reach wind speeds comparable to those of a Category 5 hurricane, causing roof failure or total collapse in buildings, and severely damaging or destroying things like mobile homes, utility buildings, and trees.

Despite the power and potentially destructive nature of jet blast, there are relatively few jet blast incidents. Due to the invisible nature of jet blast and the aerodynamic properties of light aircraft, light aircraft moving about airports are particularly vulnerable. Pilots of light aircraft frequently stay off to the side of the runway, rather than follow in the centre, to negate the effect of the blast. Occasionally, when the ground surface is badly chosen, jet blast from aircraft can rip up sections of asphalt weighing up to tens of kilograms (double-digits of pounds), damaging the aircraft.

Maho Beach in Sint Maarten is famous for its unique proximity to the runway of Princess Juliana International Airport, allowing people to experience jet blast, a practice that is discouraged by the local authorities. A tourist was killed on 12 July 2017 when she was blown away by jet blast, which caused her head to smash into concrete. Skiathos Airport in Greece similarly allows people to experience jet blast, as its runway is located near a public road.

Propeller planes are also capable of generating significant rearwards winds, known as prop wash.