Industry voice: Bird and drone strikes
Helicopter operations are particularly vulnerable to bird strikes and the risks of drones venturing into airspace. Terry Palmer recommends training to avoid them and other tips for staying safe
Bird strikes to aircraft are not uncommon. They are responsible for hundreds of deaths and cost millions in aircraft damage. In air medical operations, recent fatal accidents can be linked to bird strikes. Bird strikes have smashed windshields, blocked engine air intakes, broken pitot heads, damaged brake hoses, and caused significant rotor head or helicopter tail rotor damage.
According to the Federal Aviation Administration (FAA), an average of 47 aircraft strikes are reported daily within the US airspace system. Most of these involve commercial aircraft below 3,500ft, often close to takeoff and landing. Since the threat to helicopter operations is more pronounced, with most operations at a low altitude, the FAA issued a revised Special Airworthiness Information Bulletin (SAIB AIR-21-17R1) in October 2023 advising rotorcraft operators on mitigation strategies. As part of the FAA’s new Rotorcraft Safety Promotion Concept (RSPC), the agency suggests installing safety enhancement equipment and wearing helmets and visors. Pilots are advised to keep rotorcraft away from bird-dense environments when planning a flight. It is also important to understand seasonal bird migrations in the local environment. The FAA suggests reducing airspeed when practical because over 75% of all bird strikes occur at speeds above 80kts. Airspeed reduction should be considered to allow greater reaction time for the pilots and birds.
They also suggest increasing altitude where a bird strike is 30% less likely for every 1,000ft above 500 AGL. Therefore, pilots should fly at the highest altitudes possible when environmental conditions allow. Altitude is your friend and an expeditious climb to cruising altitude should be completed at best rate of climb. Departure from cruising altitude for landing should be completed as late as possible to avoid flying low level for any extended period of time in high bird-risk areas.
Training to avoid bird strikes
While all of these suggestions are excellent mitigation techniques, birds can be unpredictable and pilots should always be on the lookout for bird activities. Most encounters happen during the day, but consider other scenarios such as flying over a lake at night at low altitude and startling sleeping ducks or geese. There would be little or no warning before they could strike the aircraft.
Most of the aircraft manufacturers are adding safety enhancements and bird resistant designs; however, crew complacency could still lead to disaster. How do we train to avoid the complacency and potential bird strikes?
Training to avoid the birds is the best place to start. It is important to include a discussion on bird migration patterns and avoidance techniques
Training to avoid the birds is the best place to start. It is important to include a discussion on bird migration patterns and avoidance techniques.
Vigilance is key to preventing incidents with birds – it is essential to know where they are. Many birds are colored to blend in with the terrain so they may be difficult to spot.
Birds prefer the same altitudes used in most helicopter operations, therefore flying at a higher altitude can add a level of safety. Birds will tend to dive if they feel threatened.
Dawn and dusk are the highest risk. It is also more difficult to see flying objects in the low light, so avoiding these times of the day can help.
Pre-flights should also include a search for bird nests. It can take less than an hour for birds to take up residence in a parked aircraft.
During training there should also be discussion on what to do in the event of an incident. Training centers with simulation have added birds into the training scenarios. This provides the ability to understand the short reaction time and practice possible emergency procedures. All of these remind us to stay situationally aware.
Beware the untrained drone pilot
Now, as technology advancements have placed drones in the airspace environment, we are no longer only concerned with the migration and habits of natural birds. We are now adding a human element: the drone pilot. Drone pilots who are licensed and trained to understand the regulations and sharing of airspace are not the main problem; the challenge is the recreational drone pilot who may be unaware of the dangers to aircraft and personnel, or commercial drone operations where training was lacking.
Drones are easy to purchase and new owners are not always aware of the regulations and airspace restrictions. Some commercial and public safety drone operations, even though they follow the rules, do not realize the need to communicate with local air medical operations as to their location. Recently, several air medical operations have reported that they were unable to take off from a scene due to drone activity. This delayed patient care. They had no way to contact the drone operator because neither law enforcement nor the air medical operator could locate the drone pilots. This is a growing concern.
There are now drone-tracking systems that can identify the drone and the location of the pilot
New technology may have mitigation for such dangers. There are now drone-tracking systems that can identify the drone and the location of the pilot. Portable options are now becoming available that can allow law enforcement who are clearing a landing zone to check for drones, advise the helicopter crew, and inform the drone pilot that the drone must land or exit the area. This will increase safety and efficiency at a landing zone. These units can also be used at airports, public venues, hospitals or anywhere that drones may be a hazard to safety.
Communication and public awareness on drone regulation and safety are the keys to preventing encounters. If your company or department uses public safety announcements in the professional media or on social media sites, there could be something published about drone safety. Community organizations and commercial business can work together to mitigate the risk.
Birds and their mechanical counterparts, drones, may be unpredictable. Communication and training can increase awareness. Expect the unexpected. Be prepared to stay safe.