Much has been made of the reported sighting of a drone at about 6000ft by the pilot of an Airbus A320 on climb-out from Christchurch International Airport last week.

Not surprisingly, the New Zealand Airline Pilots' Association has expressed alarm that uninformed persons can buy a UAV and operate near an airport, "seemingly with little idea of the seriousness of their actions".  This is a perfectly reasonable concern - though UAVs generally do not fly particularly fast and may weigh only a few kilograms, a jet aircraft could be flying at 150 to 170kt - and ingestion of a UAV by an engine, or impact at such speed could seriously damage the aircraft or the pilots it if penetrated the windscreen.  Regulatory bodies may now be tempted to impose more restrictive conditions on all model aircraft in response to the perceived risk of collision.

Unfortunately, this particular genie is out of the bottle.  Many people have purchased multi rotor drones on the Internet and the FAA has warned that there could be a million drones under the Christmas trees of the nation this year.  No amount of regulation is going to stop some of these machines being flown in areas where more responsible pilots would not fly, while licensing is not going to help - if you are going to use a gun illegally, you don't buy a firearms licence.  Registration and marking of the drones will not help much either - they are too small to carry registration letters readable from another aircraft.  Probably the only approach likely to have an impact is education of drone operators and the use of simple posters and comic strip style information delivery to purchasers of model aircraft of all types.

The new CAA regulations in New Zealand have taken a reasonable approach, more clearly defining what is permitted under the Rule Part 101.E for model aircraft and Airways and its partners have made available a website called Airshare for UAV flight planning and information exchange.  A further Rule, Part 102, has set out the requirements for commercial operation of unmanned aerial systems.  Provided that UAV and model aircraft operators continue to obey the new rules, there will be no conflict with full-size aircraft.  Of course, you can't legislate against stupidity and there will always be someone who wants to see how high the aircraft can fly.

Some commercial drone operators have jumped on the bandwagon and called for even more restrictions on hobby operators, but they are not taking into account the capabilities of modern consumer-level drones.  Suggesting that an enthusiast might only be able to fly his or her drone up to 200ft before losing control is somewhat condescending towards serious aircraft modellers and is just not realistic.   Even cheap autopilots are capable of flying the aircraft to waypoints out of sight of the operator and returning to the launch point.

As to whether the drone reported could have reached 6000ft, there is insufficient information in the various reports to reach a conclusion.  Was it a multi rotor or a fixed wing aircraft?  A multi rotor must support its weight by generating thrust from the propellers, which uses up battery power at a high rate.  On the other hand, a fixed wing aircraft supports its weight with the lift generated by its wings, so, under normal flight conditions, battery power consumption is considerably less.  In January 2014, I flew our Fox fixed wing UAV up to 5500ft AGL in the Taylor Dry Valley in Antarctica.  The purpose was to photograph some of the ridges surrounding our campsite.  The flight was conducted with full approval from Mac Centre, the flight control centre for Antarctica, located at McMurdo Base.  In reaching this altitude, we ran the batteries down to our minimum safe reserve and had only a few minutes of useful photography time, gliding down to our landing point with the motor off.  A multi rotor probably could not have achieved this climb.

What would be the point in flying a UAV at 6000ft?  In most cases, photographs and videos taken from this height would be of little use.  When we conduct surveying operations with a UAV, we generally fly at 250 to 350 ft AGL, to get good resolution in the images, so well clear of general aviation operations.

So, we have to accept that the A320 pilot did indeed see some flying object at 6000ft, but as to whether it was a multi rotor or fixed wing UAV, or even another type of craft, such as a microlight, we have no further information.  Of one thing I am sure: no serious UAV operator would fly so high close to an airport because of the risk to other aircraft and the low resolution of resulting images.

The comments above are my own opinions and do not necessarily reflect the views of the Auckland University of Technology UAV operations group, or the University itself.  The post has been edited to resolve the missing part of the penultimate paragraph.