Protecting aircraft from lightning strikes

Citation

(2001), "Protecting aircraft from lightning strikes", Aircraft Engineering and Aerospace Technology, Vol. 73 No. 1. https://doi.org/10.1108/aeat.2001.12773aab.012

Protecting aircraft from lightning strikes

Protecting aircraft from lightning strikes

Keywords: University of Florida, Aircraft industry, Protection

An experiment to learn details about what occurs at ground zero of a lightning strike may lead to more effective lightning protection for airplanes, University of Florida (UF) (Gainsville, Florida) researchers report.

While lightning rarely causes plane crashes, it does occur, and the US Federal Aviation Administration (FAA) will use the information gained from this experiment to update its tests for new airplanes to ensure that they are adequately protected.

"We may determine that some of the parameters in the FAA's lightning test standards do not represent what is going on when lightning strikes and should be modified according to our measurements", says Vladimir Rakov, professor of electrical and computer engineering.

On average, lightning strikes a commercial jet once for every 10,000 hours in the air. However, most strikes cause no significant damage, because the lightning current flows harmlessly across the metal skin of the aircraft, according to Rakov.

"Once in a while, the consequences of a lightning strike can be very, very dramatic, even catastrophic", say Rakov. In one of the most famous lightning related crashes in US history, a Boeing 707 was brought down in Maryland in 1963 – killing all 81 people aboard. Since then, lightning has been implicated in a handful of jet crashes worldwide.

An increasing reliance on composite materials in aircraft construction creates the potential for additional problems, because the composites can allow a connection between lightning and airplane electrical circuits, Rakov says.

The experiments at UF's International Centre for Lightning Research and Testing (ICLRT) rely on a time-tested method for studying lightning – the use of trailing wire rockets shot towards storm clouds.

While the researchers often launch rockets from a tall tower launch pad for the experiment located in a pit in the ground, rocket launcher and other equipment is below ground to eliminate interference. The mesh prevents the lightning from arcing. The set-up is designed to create the perfect environment to measure the electromagnetic currents, and shockwaves near a lightning strike.