What is the average speed of jet blast?

Understanding Jet Blast

Jet blast is a powerful force that is generated by the engines of aircraft during takeoff and landing. It is a phenomenon that can cause serious injuries, damage to property, and even fatalities if not handled properly. Therefore, it is important to understand the characteristics of jet blast, including its speed and the factors that affect it.

Definition of Jet Blast

Jet blast is the high-speed exhaust gas that is expelled from the rear of an aircraft’s engines during takeoff and landing. It is a result of the combustion of fuel in the engine, which creates a high-velocity stream of hot air and gases. This stream of air can reach speeds of up to several hundred miles per hour and can extend up to several hundred feet behind the aircraft.

Factors that Affect Jet Blast Speed

Several factors can affect the speed of jet blast, including the type and size of the aircraft, the power of its engines, the weight of the aircraft, the altitude, and the weather conditions. The design of the aircraft’s engines can also impact the speed of jet blast, as can the angle and configuration of the engine nozzles. Additionally, the surface on which the aircraft is operating can affect the speed of jet blast, with harder surfaces like concrete and asphalt creating faster and more concentrated jet blast.

Measuring Jet Blast Speed

Jet blast speed can be measured using various instruments, including anemometers, which measure wind speed, and pitot tubes, which measure the pressure of the air. These instruments can be placed at various distances behind the aircraft to measure the speed and intensity of the jet blast.

The Average Speed of Jet Blast

The average speed of jet blast varies depending on the factors mentioned above. However, studies have shown that the average speed of jet blast from commercial aircraft is around 80-100mph at a distance of 100ft behind the aircraft. This speed decreases as the distance from the aircraft increases.

The Fastest Jet Blast Speed Recorded

The fastest jet blast speed ever recorded was from a Boeing 777-300ER aircraft, which generated a maximum speed of 166mph at a distance of 50ft behind the aircraft during a test conducted by the FAA. This speed is equivalent to a category 2 hurricane.

The Slowest Jet Blast Speed Recorded

The slowest jet blast speed recorded was from a small general aviation aircraft, which generated a speed of around 30mph at a distance of 50ft behind the aircraft.

Jet Blast Speed Compared to Other Forces

Jet blast can be compared to other forces such as tornadoes, hurricanes, and strong winds. While the speed of jet blast is not as fast as the most powerful tornadoes and hurricanes, it can still cause significant damage and injuries.

Safety Precautions Around Jet Blast

There are several safety precautions that should be taken around jet blast, including staying behind designated barriers or fences, avoiding standing directly behind aircraft engines during takeoff or landing, and wearing ear protection to protect against the noise of the engines.

Regulations for Jet Blast Speeds

Regulations exist to ensure that aircraft do not generate excessive jet blast speeds that could cause harm to people or property. These regulations vary depending on the country and the type of airport, but generally require aircraft to maintain certain distances from people and property during takeoff and landing.

Conclusion: Importance of Jet Blast Speeds

Understanding jet blast speeds is crucial for ensuring the safety of people and property around aircraft during takeoff and landing. By following safety regulations and taking appropriate precautions, the risk of injury or damage from jet blast can be minimized.