Inclement Weather... Protecting Ground Operations Personnel
Although most people think of hazards to aircraft in-flight and on the ground when it comes to inclement weather, ground personnel are at a higher risk on the airport ramp.
Personnel working on the airport ramp are expected to complete their duties while subject to high noise levels and effects of engine exhaust. Add in heavy rain, high winds, lightning, and the possibility of freezing rain or hail – and you can quickly see that the weather hazards for ground personnel are significant, and many times given little thought by airport and aviation company management.
Does your facility or company have a severe weather warning system in place? Is there a written policy and procedure on operations in severe weather – and what triggers indicate that operations should be halted until conditions improve and severe weather hazards are no longer present or predicted?
The National Weather Service does issue Airport Weather Warnings (AWWs). AWWs are designed to address weather conditions that may adversely affect ground operations at airports. This information has proven useful to airport manager, fixed-base operators, ground personnel, and others responsible for safety of ground operations.
AWWs are not intended for use or consideration for in-flight operations. An AWW is written in plain language, free text format. It will include the triggering phenomenon, location, start time (end time as needed), and may include additional remarks.
AWW emergency alert issuance criteria are established according to local airport requirements and should be reviewed annually. They include:
- Surface wind gusts of 40 knots (46 mph) or greater
- Onset of freezing rain
- Cloud to ground lightning within five (5) miles (8 km) and approaching the airport
- Thunderstorms with hail of ½ inch (1.2 cm) or greater
- Onset of heavy snow
Lightning strikes are extremely dangerous to ground personnel. The open areas of airport ramps and high concentration of metal ground support equipment (as well as aircraft themselves) make the airport ramp a high hazard to personnel during conditions suitable for lightning. There have been documented cases where lightning has struck an aircraft and the electricity passed through the aircraft and entered the ground near ground personnel servicing the aircraft. It doesn’t require a direct hit for severe injuries and burns to occur to personnel.
Although no place is absolutely safe from lightning threat – inside a building with doors closed will provide the greatest reduction of risk.
Ground personnel many times can not hear warnings from lightning warning systems if they exist at your facility. Therefore, it is important for a procedure and a responsible person be designated to ensure that ground personnel are instructed to cease operations and seek shelter until the hazardous conditions have passed.
For more information on the National Weather Service Airport Weather Warnings (AWWs), see:
https://www.nws.noaa.gov/directives/sym/pd01008001curr.pdf
Examples of lightning prediction and warning systems can be found here:
https://www.dtn.com/weather/aviation/