Page 13 - 2017-Issue4

SMALL DRONES, BIG DAMAGE - Show Collision Testing Report 13

Small Drones, Big Damage:

Show Collision Testing

Report

10-metre long gas gun shooting drone components into an airliner windscreen.
Sounds scary? It is less scary than a real mid-air collision between a drone and
a plane or a helicopter. With the prospects of this happening in the future,
researchers have geared up to find out exactly how dangerous a collision
between a drone and a passenger jet or helicopter could be. The results of this
state-of-the art laboratory collision testing and modelling show that even a
small drone could do substantial damage.

he UK Department for Transport, the Military Aviation a critical part in the severity of a collision. Exposed metallic
TAuthority and the British Pilots’ Association BALPA, components of drones can cause significant damage to
published the results of those tests in July, covering both aircraft windscreens. This is a particularly important aspect
helicopters and fixed-wing aircraft. The findings – for drone manufacturers, who would be able to adapt the
summarised in this report – reveal that consumer drones materials and designs of drones, provided regulatory
could “critically damage” helicopter windshields and tail standards exist.
rotors. Particularly vulnerable are non-bird strike certified While many studies have already tested the impact of
helicopter windscreens, typically used for general aviation bird strikes on aircraft, some drone components – such as
aircraft. Such windscreens prove to have a low resistance to the motors and batteries – are much harder and potentially
all the classes of drones tested. more damaging than ‘fluid’ birds. While comparisons to
The test showed that even the smallest drone (0.4 kg) bird strikes are useful, components of drones do not behave
would penetrate through the non-bird strike certified in the same way as an equivalent of mass bird under similar
windscreen at speeds well below the normal helicopter conditions. In fact, even lighter drones could cause more
cruising speed. For a fixed-wing drone (3.5 kilogram), it was damage than a bird.
found that the drone could penetrate a helicopter This study affirms aviation experts’ presumption that a
windscreen of this type even if the helicopter was stationary. drone strike is not like a bird strike: it can be much more
The bird strike certified helicopter windscreen, generally severe in consequences. And it shows that further testing is
more resistant, was not spared. Heavier drones could still necessary: More scenarios need to be examined, testing
penetrate these windscreens at helicopter’s typical cruising different aircraft components, including aircraft engines,
speed. And by using different computer simulations and and different models of drones. This would help us get a
modelling, researchers found that helicopter tail rotors better understanding of the hazards and advance with the
would be vulnerable to impacts with all types of drones. solutions. And, it would help the European regulator – who
Due to the very high speed of a rotating tail rotor blade, it is busy drafting risk-based, operation centric legislation for
could be critically damaged by an impact with any drone. drone integration in Europe – to actually know the risk that
Even windscreens of airliners, which have a more future EU safety rules must be able to mitigate.
resistant construction than those of helicopters, are
vulnerable to damage. It was found that the airliner
windscreens, although substantially damaged, could retain This article, originally published on the Euro
integrity if hit by a drone up to speeds typically flown at Cockpit Association (ECA) website, has been
during the aircraft landing and later stages of the approach. reprinted with permission from ECA.
The research tests showed that the drone construction plays

InterPilot | The Safety and Technical Journal of IFALPA ISSUE 4 | 2017