It looks as if the 17 April “drone strike” on a British Airways aircraft on approach to Heathrow airport may not have been a collision with a drone after all. Maybe just a wind-tossed plastic bag – the investigation is still in progress.
In an aircraft travelling at about 150kt (170mph/275km/h) on final approach, small objects can suddenly appear and flash past. At that point the pilots are concentrating on monitoring the aircraft’s performance and aiming it at the runway. So it’s easy for a pilot to misidentify whatever the object is.
But does that mean we don’t need to worry about drones?
There some very simple rules about how you may operate a drone, so the relevant question is whether people will obey the rules – or even read them in the first place.
Drones are getting popular among ordinary people, mainly for airborne video recording or still photography. First the selfie, then the selfie-stick, now the airborne selfie?
Lads mags are full of enthusiastic advice for gadget-crazy young men. Some lads will be given a drone as a birthday present. If they are given one, will they read the operating instructions when they’ve opened the pack, let alone the legal restrictions on their use?
Some won’t, but does that mean they will inevitably operate their drone in such a way as to endanger aircraft? The law of averages says that one day someone will – possibly unintentionally – fly a drone in an airport approach or departure path.
But given another contemporary public threat to aircraft – commercially available hand-held laser pointers being shone into pilots’ eyes during take-off or final approach to land – an unsettling mentality exists out there. Use of lasers in this way is against the law, but incidents are on the increase.
So when a drone hits an aircraft, what will the result be?
Most are small and light – between one and 5kg. If one of these hits the aircraft wings, tail or forward fuselage it will cause damage but not make it impossible for the pilots to fly safely.
But if it hits the flightdeck windscreen or the engines the results could be serious. Exactly how serious we are not sure, because tests have not been carried out.
A drone-strike on an engine will probably cause its failure, and if it’s a heavier device it might smash the windscreen and injure or kill a pilot. Either of these events is very unlikely to be terminal for the aircraft, but they both could be. This would depend on the degree of direct damage and whether or not it has secondary effects.
Large-scale public drone use is still not with us, but it’s on the way. With greater use will come greater awareness among users as well as the public. That’s what the Civil Aviation Authority and Department for Transport are banking on – the public’s basic common sense.
Terrorists are unlikely to use drones against aircraft because there are more effective ways of attempting to disrupt commercial aviation.
But for those on the fringes of society – the kind who use powerful laser-pointers – dicing with risk can be attractive.
What the authorities have to decide is whether this risk is serious enough to require, for example, all drone users to register. Or some form of unique identifier like a transponder or GPS tracker to be fitted to all machines.
They’d rather not have to introduce expensive bureacracy to control the public use of devices that, used sensibly according to existing rules, are pretty much harmless.