abridged from GASCO
Many pilots do not realise that if they collide with a soft feathery
bird, the effect of speed turns it into a missile capable of inflicting
considerable damage. This has included smashed windshields (killing
pilots), blocked engine air intakes, broken pitot heads, damaged brake
hoses, holed structures and helicopter tail rotor damage. Out of about
100 incidents reported each year by UK general aviation pilots, about 5%
result in damage. The advice given in this Leaflet may provide greater
awareness of the problem, and perhaps further reduce the number of
collisions as well as help pilots to minimise the consequences if a bird
strike does occur.
planning the flight
Check aerodrome documentation and NOTAMS (issued by some countries as
BIRDTAMS) for information about permanent or seasonal bird problems at
both departure and destination aerodromes.
Plan to fly as high as possible, only 1% of general aviation bird strikes
occur above 2500 ft (although a jet airliner struck a vulture at 37,000
ft off the W. African coast!)
Do not fly over bird and
wildlife sanctuaries marked on aeronautical charts.
Avoid flying along rivers or shore lines, especially at low altitude.
Birds as well as pilots use these useful navigational features.
Note also that inland waters and shallow estuaries, even outside the
breeding season, may contain large numbers of gulls, waders and wildfowl
which make regular flights around dawn and dusk. In order to minimise the
possibility of bird strikes and unnecessary disturbance of birds, DO NOT
fly low over such areas. Note: It is an offence to deliberately disturb
nesting birds, pilots have been successfully prosecuted for doing so.
Avoid off- shore islands, headlands, cliffs, inland waters and shallow
estuaries, so as not to disturb nesting colonies.
Helicopters cause more disturbance to bird colonies than fixed wing
Bear in mind that birds do fly at night.
If there are two pilots, discuss emergency procedures before departure,
including those if the cockpit communications are lost.
Up to 8090 kts, birds
usually have time to get out of your way, but the higher the speed, the
greater the chance of a strike.
If your flying requires lengthy periods at low level, consider wearing
head protection with polycarbonate visor. Pilots lives have been saved
by their helmets, particularly in helicopters. Use goggles and a head
protection during air racing.
In July and August the risk of a strike is at its greatest because many
inexperienced young birds are present. Also, the flying abilities of
adults may be impaired as they moult their flight feathers.
Birds of Prey have been known to attack aircraft!
at the aerodrome and
In springtime, pre-flight the aircraft thoroughly as birds can build a
nest almost overnight. Any signs of grass etc may necessitate further
investigation of hard to inspect corners. A nest under the cowling could
catch fire, or one in the tail area can restrict the flying controls.
As you taxi out, listen for any warnings of bird activity on the ATIS
e.g. a mass release of racing pigeons.
While you are taxiing, look for birds on the aerodrome. Note that the
most frequently struck birds, gulls, have a grey or black back which
makes them hard to see on concrete or tarmac runways.
In general terms, the slower a bird's wing beat, the bigger the bird and
the more hazardous it could be.
If birds are observed on the aerodrome, request aerodrome personnel to
disperse them before you take- off. This is particularly important for
turbo- prop and jet powered aircraft operating at aerodromes mainly used
by smaller general aviation aircraft (the birds may have got used to slow
Never use an aircraft to scare birds away.
Some aircraft have windshield heating, remember that its use, in
accordance with the Pilots Operating Handbook or Flight Manual, will make
the windshield more pliable and better able to withstand bird impact.
Use landing lights during take-off, climb, descent, approach and landing.
Although there is no conclusive evidence that birds see and avoid
aircraft lights, their use will make the aircraft more visible.
If you experience a bird
strike during the take-off run, provided there is sufficient runway
remaining stop. Taxi off the runway and shut down. Inspect the intake,
engine etc for damage/ ingestion, or for bird remains blocking cooling or
other airflow ducts. Several airline incidents have occurred where
turbine engine damage or high vibration developed during subsequent
flights because of undetected engine damage. Don't forget to check
landing gear and brake hydraulic lines, downlocks, weight switches etc.
Where the take-off must be continued, with an engine problem, properly
identify the affected engine and execute emergency procedures and tell
the aerodrome why you are returning. It is essential to FLY THE AIRCRAFT.
If you see bird(s) ahead of you, and it is safe to do so, attempt to pass
above them as birds usually break-away downwards when threatened. Be
careful when near the ground, and never do anything that will lead to a
stall or spin.
As you pass through a flock, or feel a strike, FLY THE AIRCRAFT. Maintain
the correct speed and use whatever performance remains to reach a safe
If structural or control system damage is suspected (or the windshield is
holed) consider the need for a controllability check before attempting a
landing. During such a check at a safe height, do not slow down below
threshold speed. Be wary of unseen helicopter tail rotor damage.
If the windshield is broken (or cracked), slow the aircraft to reduce
wind blast, follow approved procedures (depressurise a pressurised
aircraft), use sunglasses or smoke goggles to reduce the effect of wind,
precipitation, or debris, but remember to fly the aircraft . Don't be
distracted by the blood, feathers, smell and windblast. Small general
aviation aeroplane and helicopter windshields are not required to be
tested against bird impact and the propeller gives little protection.
Gulls, pigeons, lapwings and even swifts can hole light aircraft
If dense bird concentrations are expected, avoid high-speed descent and
approach. Halving the speed results in a quarter of the impact energy.
If flocks of birds are visible on the approach, go-around early for a
second attempt, the approach may then be clear.
After landing, if you have had a bird strike, check the aircraft for
Report all bird strikes to the appropriate authority.
Check NOTAMS/ATIS for bird activity at departure and destination
Plan to fly as high as possible, most birds fly below 2500 ft. -
Avoid bird sanctuaries and coastlines in spring. -
Pre- flight the aircraft thoroughly, birds nests can be built (or
rebuilt) in a few hours. -
Many hazardous species are coloured such that they merge into the
If you see hazardous birds on or near runways, get aerodrome personnel
to move them BEFORE you take off. -
The higher the speed, the greater the risk and consequential damage.
Birds usually escape by diving, so try to fly over them, but do NOT
risk a stall or spin. -
Most general aviation aircraft windshields etc are NOT required to be
able to withstand bird strikes. -
If the windshield is broken, avoid distraction FLY THE AIRCRAFT. -
Report ALL bird strikes.