The alleged Gatwick drone in December 2018

Soon after 9pm on Wednesday 19 December 2018, a rainy winter evening, a visual sighting of a couple of drones was reported, this was considered by senior management as a sufficient risk and so all the flights were suspended.

Members of the press were soon at Gatwick suitably equipped to capture photos and videos in darkness, even at great distance.

The assistance of Sussex Police was sought and so began Operation Trebor.  By the second day, 10 Royal Air Force (RAF) personnel that were part of the Defence Warning and Reporting Flight (DWaRF) section of 8 Force Protection Wing were deployed with a counter drone (C-UAS) system under Military Aid to Civil Authorities (MACA).

The voices of the drone community, manufactures, engineers, experts on the subject matter were rarely heard, even when UK drone operators were interviewed they were corralled into answering “what if” questions rather than being quizzed on their views and concerns on the narrative.

In the situation reports being distributed internally by the Department of Transport (DfT) the statement “This incident is being regarded by industry as malicious attempt to disrupt operations” was circulated, yet this was far from the truth.  Not only those in the UK industry, but drone experts globally were bemused, asking how is a drone flying in the rain (few drones, especially in 2018 were sufficiently IP rated to handle rain), why would any semi-competent drone pilot with nefarious intent have the lights switched on, how was an industrial drone that would be a size and speed easy to photograph not being evidenced?  Those were just some of the questions.

It is not a case of view’s changing with hindsight, those with an engineering mindset were unconvinced at the outset, Jenny List of the hardware web magazine Hackaday echoed the concerns being voiced on social media and went further, encouraging the industry to keep the knowledge of a poor investigation alive.

Given that they will no doubt be reviewing drone legislation in the wake of this fiasco it is particularly important that the investigators consult people with specialist knowledge in the field, demand physical proof rather than heresay, and most importantly question accounts that stretch credibility.

As multirotor enthusiasts we must keep the issue of poor investigation alive though, for if we let it be buried once more it will come back to trouble us again.

Meanwhile Steve Timewell of Drone User magazine was taken out of context and mocked in the press for saying that the sighting could be a UFO, which did not for a moment mean it was an alien invasion or any other such nonsense, merely many sightings of lights in the sky throughout history have been misidentified, maybe the light was a helicopter for example?  The media mocked his plastic bag suggestion, completely forgetting the most significant drone hysteria prior to Gatwick, related to Heathrow and was likely due to a plastic bag.

Here are a small selection of comments, made at the time by commercial drone operators on social media:

TV crews, CCTV, Police, Army, and Joe Public yet still no images.

125,000 stranded travellers plus all the major TV and press outlets and NOT ONE SINGLE IMAGE OF A DRONE ANYWHERE!! Incredible!

Photos proven to be heli and given the heavy rain and wind it certainly doesn’t sound like any drone I know of.

Am I the only one wondering how these “drones” can be flying over Gatwick with high winds and rain? Well outside operating limits of most commercial drones

• The first drone sighting plus potentially the follow on sightings were in weather conditions consumer and commercial drones would struggle with.  Few drone models can fly in the rain, the SkyRanger flown by Sussex Police being one of the exceptions.  Such drones are large and relatively slow, being fairly easy to photograph.

The historical weather data from Gatwick can be downloaded here: Gatwick Weather Data METAR (METeorological Aerodrome Reports)

• Press photographers were at Gatwick within around an hour, equipped with modern cameras and lenses, with high ISO bodies capable of capturing images at significant distances even in low light.  In addition, members of the public will have been equipped with cameras for their holidays, or at least modern camera phones.  A Scotland Yard detective quoted by the New York Times noted that he did not understand how there could be witness statements but no video to back up the claims, especially in the age of smartphones.

Giles York, the Sussex police chief constable at the time, gave evidence to a parliamentary committee that fell far short of explaining the lack of video which is examined in more detail on this page.

• Once counter drone systems arrived on the 20th December, sightings of the drone still continued and were not confirmed on the counter drone systems, which means one or the other was wrong, evidence discussed later on this page will demonstrate that eventually the visual sightings were disregarded.
• Photographs in the press claiming to be drones included photos known not to be, some for certain being helicopters, the light colouring seen was an aviation configuration where drone colour schemes differ.  At the time there was a potential exception, the 3DR Solo drone allowed an aviation lighting scheme to be chosen, but this was a consumer drone, its size and low powered LEDs would require it to be very close to be seen such that it could easily be filmed or photographed.
• The technical reality is the lights on drones are low powered LEDs, so much so, commercial drone operators have to buy strobes and fit them specifically to see their drone at night.  So if the sightings of the Gatwick drone involved distances well over 100m away (which evidence suggests was the case) then the lights almost certainly were not those of a drone.

The weather and the fact drones cannot be seen at distance at night, should have rung alarm bells with anyone that had a modicum of drone knowledge.

Most of the following points have required use of the Freedom of Information Act to elicit answers.

• The redacted version of the Operation Trebor debrief details the times of the sightings that closed Gatwick and they were all after sunset, suggesting sightings were typically of lights.  A note in the timeline reveals “No further suspensions of flying at Gatwick, although sightings of a drone continued” which means either the sightings were not trusted or a decision had been made to put the public at risk to allow flights to continue while there was a malicious drone in the air.  It seems highly unlikely the public would be put at risk.  Some sightings did continue into daylight, though with drone sorties taking place there was still plenty of potential for false positive sightings.

Official sensitive Operation Trebor Structured Debrief report Redacted…

• The DfT instructed that the technology used to protect airports should not be discussed with the media, however the defence company Leonardo blogged that their system Falcon Shield was present at Gatwick along with Metis Skyperion.  DJI’s AeroScope was also used.

• There is not even a written description of what the drone was supposed to look like, fast/slow, big/small, blue/white, quad/hex etc, neither the DfT or the CAA have any such description.

Why can’t anyone even describe what the drone looked like?  If witnesses can’t describe what they saw, how does anyone know for sure it’s a drone?

• The UK Airprox Board have revealed that not a single pilot reported a drone airprox in the vicinity of Gatwick from the 19th onwards.  Even in periods where the runway was closed there was still air traffic including but not limited to National Police Air Service (NPAS) helicopters and air ambulances.
• The defence company Leonardo admitted that Gatwick Airport along with Sussex Police conducted drone sorties to test the counter drone systems, even though the systems had been used in the past and were known to work, this was likely due to the fact none of the visual sightings were being confirmed.  So without doubt these flights will have added to “the noise” of drone reports.

Gatwick, in conjunction with Sussex Police, launched a number of ‘friendly drone test sorties’ during 21-23 December, all of which were detected and reported on by the Falcon Shield system.

• The complete reopening of the airport took longer than it should have, the counter drone systems arrived on the evening of the 20th, the airport was closed through the early hours and then only gradually returned to operation on the 21st before yet again suspending flights at 5pm due to a visual sighting that wasn’t confirmed on the counter drone systems.  The DfT have confirmed they had no influence on these decisions and it was ultimately for Gatwick Airport to decide.  In a nutshell the systems should have been trusted at the outset (why bring in an asset if you’re going to override it).

Here is an annotated timeline to help visualise how there appears to have been indecision after the arrival of counter drone systems (annotated as C-UAS):

When reading the timeline above, consider the information Leonardo published on the operation:

…the RAF confirmed to Gatwick Airport operating authorities the absence of any ‘hostile or malicious’ drone activity.

So you have Gatwick Airport and Sussex Police saying there is a drone because there is a sighting, then the RAF saying no there isn’t because the systems say so.  It appears after the incident at 17:00 (5pm) on Friday 21st that Sussex Police finally began reacting to the RAF information.  The RAF have confirmed they had a “scheme of manoeuvre” which left them out of the decision making:

HQ Air will generate equipment and personnel required to deliver a C-UAV DTI ability to Sussex Police. Its employment will aim to identify UAVs within the ATZ of Gatwick Airport; all subsequent reporting and related decision making will be undertaken by Sussex Police with no input from military personnel.

By the 21st ministers were already preparing a script to manage media communication.

We cannot discount the possibility that there may have been no drone at all.

Jason Tingley was an exceptionally experienced officer with decades of service to Sussex Police, just over a year after the Gatwick drone incident he left Sussex Police not even mentioning his role with this operation on LinkedIn where at least 71 colleagues at Sussex Police endorsed his skills and in 2023 he took a role with the Office of the Police and Crime Commissioner for Sussex.

The removal of Jason Tingley who was then a Detective Chief Superintendent looked particularly sinister, when has a major police operation removed an officer from press duties?  When viewed in context of the timeline above it looks more than coincidental that when Tingley revealed there may not have been a drone it was evident the visual sightings were no longer playing a role in decision making before his admission on BBC News.

It’s reasonable to surmise that eventually the penny dropped, with the police realising thanks to the counter drone capability that there may never have been a drone, but it appears the narrative had run along so far that it simply wasn’t an option to admit this to the public.

Behind the scenes, a the DfT situation report #9 revealed that by the time of Tingley’s interview (the 23rd) plans were already underway to withdraw the police presence from Gatwick.

Despite the Sussex Police debrief recording an operation that appears to have run until the 31st December that must have been precautionary with reduced resources, the RAF had packed up and left by the 24th December, being satisfied there was no malicious drone to detect.

The NPAS (National Police Air Service) are the forgotten service at Gatwick in 2018, the media and public likely assumed the helicopters deployed over Gatwick Airport in 2018 were Sussex Police assets, however, the police helicopters we see across the UK are part of a centralised air support with West Yorkshire Police being the lead force with the NPAS Operations Centre being at the force’s HQ in Wakefield.

It wasn’t until FOI 1790907/23 that it was public that the NPAS crews did not see the alleged rogue Gatwick drone.  The NPAS crews were the most experienced with airspace and being capable of identifying a drone out of all the police assets deployed.

When the revelation was published in the press the NPAS spokesperson played down the capability of the service and how the helicopters were deployed, likely to avoid conflict with Sussex Police.

Between December 19 and 23, 2018, NPAS was tasked by Sussex Police to search an area near Gatwick Airport following reports of drone activity. On occasion, the searches were limited as the crews were diverted to other high priority taskings.
It is important to note that small drones can be almost impossible to see from the air and our crews are tasked to look for those operating the drones from open land.
NPAS crews did not sight any suspected drone operators, or drones, on the occasions they flew.

The FOIA data as well as NPAS operations already in the public domain, paints a picture that suggests the lack of a sighting by NPAS crews is far more significant than their spokesperson would have the public believe.

First of all the assertion that “the searches were limited as the crews were diverted to other high priority taskings” is misleading as until the RAF arrived, when an NPAS helicopter was diverted, it had already generally been on mission a significant amount of time and an alternative helicopter was scrambled to take its place and this is shown in the flight logs retrieved in FOI 2074847/24 to West Yorkshire Police.

For example, the data clearly demonstrates an effort by NPAS to keep blanket coverage of Gatwick Airport, when the helicopter from Lippitts Hill was diverted at 13:49 to another task, only 4 minutes later another unit was deployed from RAF Benson, while that would have involved some journey time there was clearly a generally successful effort to keep the airport under the gaze of a helicopter crew.

There were 3 bases utilised:

NPAS Redhill (Redhill Aerodrome) in Redhill, Surrey

NPAS Lippitts Hill in Loughton, Essex

NPAS Benson (RAF Benson) in Wallingford, Oxfordshire

The suggestion “our crews are tasked to look for those operating the drones from open land” doesn’t stack up against the actual events, a screenshot at the time of the initial Gatwick panic posted by a BBC cameraman, clearly shows NPAS G-POLF flew around the airport clearly looking for the drone itself.  Ironically it was this very NPAS helicopter that was photographed and published in a national newspaper as being the Gatwick drone.  Another police helicopter G-MPSC was photographed flying on day 2 over Gatwick Airport around the time of another alleged Gatwick drone sighting.  This also demonstrates that deploying drones and helicopters, especially with lights on added to the confusion.

The suggestion “small drones can be almost impossible to see from the air” defies outcomes that have been seen in practice and ironically had been publicised only a month before Gatwick when a DJI Phantom was caught by an NPAS, additionally NPAS crews have successfully pursued drones as small as the DJI Mavic, these are drones far smaller than the one Sussex Police imagined was flying around Gatwick.  Maybe the spokesperson used the word “small” deliberately here, given the Gatwick drone was always asserted to be a large commercial sized drone?

It should be noted, drones have a very strong thermal signature so are easy to identify, this is why counter drone systems utilise thermal cameras as well, this is a screenshot from Leonardo’s Falcon Shield system, the heat (shown as white) emitted by the motors and battery are clear to see.

The flights logs from the Gatwick incident are included below:

At a parliamentary defence committee (29/10/2019) on the topic of the Domestic Threat of Drones, the chair (Dr Julian Lewis MP) quizzed Giles York, the then Sussex police chief constable about the lack of any photos or videos of the Gatwick drone, he gave an explanation that fails to make logical sense:

Gatwick Airport, is a huge area. It’s a huge area and you try and tell me what a drone half a mile away at the other end of the runway looks like from here.

Film it on your best phone that you’ve got then show me the footage…

The transcript can be read in full here: Giles York – evidence session on the Domestic Threat of Drones – Tuesday 29 October 2019

Let’s dissect this explanation, first off there’s no chance anyone is making a credible visual identification of a drone half a mile away at night, at best they’re seeing a light that could be a helicopter, plane or crane, drone lights aren’t that powerful.  Professional photographers that were at Gatwick have accounts of how from the ground a helicopter or plane looked like a potential drone and had to be checked on a telephoto lens to confirm otherwise.

Then there’s the implication the human eye can see further and better than a lens on a camera phone, that doesn’t add up, nor is it fair to make the blanket assumption everyone in the airport was equipped with nothing better than a camera phone.  Maybe he didn’t get the memo about the press photographers with their 400mm zooms?

Finally there is an omission of some key information, from the 20th Gatwick had Falcon Shield deployed on the roof with at least two optical/thermal sensors, they just happen to be able to track and film a drone 1km (well over 1/2 mile) away.  Drones have a good thermal signature due to heat from the motors and battery which aids automated tracking.

In the following video, the same system deployed on the roof at Gatwick, shows itself capable of tracking a consumer drone, in this example the drone is clearly visible as a DJI Phantom at 1km, a larger drone would be even simpler to track.  According to the specifications the NERIO-ULR when operated manually can identify an object 2m x 0.5m at over 10km.

As soon as I read the actual weather (METAR) on that fateful night it became obvious that something was not adding up. Without a single piece of evidence Gatwick has become the stick that launched a thousand counter drone systems and rationale for pay to play low level airspace. Upsetting in its wake model aircraft flight, something that has existed for much longer than manned aviation. Plenty of money has been made on the back of the FUD created by one air traffic control shift on a dark and rainy evening.

Gary Mortimer // Editor sUAS News // South Africa

Once the assets the RAF brought to Gatwick proved the absence of rogue drones and the operation swiftly wrapped up, that left the dilemma, if a journalist was ever to pore over the events at Gatwick they would see a contradiction.  The visual sightings Sussex Police claim are robust contradict the C-UAS systems which did not detect any rogue drones, yet the systems were already proven as being able to detect drones, both prior to Gatwick and with test sorties at the time.

That left a few potential narratives to try and explain this, they’re far from robust:

• Undermine the reliability of the C-UAS systems and imply they could have been defeated by a mere airport worker with a grudge despite the fact each system is proprietary, with little known about the systems the RAF was likely to deploy prior to Gatwick happening, with so many variables to factor in this scenario, it is implausible.
• Pretend the sightings all stopped the moment C-UAS turned up.  This approach was attempted but can’t withstand scrutiny now the FOIA has revealed sightings and flight suspensions continued after the C-UAS was deployed and operating.

Let’s examine the flaws in these narratives.

First the airport worker with a grudge, the idea that if you are employed to work in an airport you’d understand fairly secret proprietary software and hardware.  The idea that you’d be an expert on hardware and software design, for a range of sensors, from video, RF, thermal, radar and you’d understand the nuances of each system and would be able to plan a mission ahead of time guaranteeing success.  The idea that’d you’d know the RAF capability and precise location each sensor would be deployed is well beyond credibility.  Not only that you’d have to avoid the world’s press with cameras on the move at random locations throughout each flight.

As an example, how would anyone have known where the Metis Skyperion driver was going to park this sensor?  The position of this sensor determines the area where RF will be scanned.

To underline the difficulty here, even counter drone experts at the time, advising the press made many mistakes, Rafael’s Drone Dome was reported as being present, this was due to a flawed identification of the Leonardo Nerio-ULR which occurred as the cover was removed from this sensor which normally displays the Leonardo branding in a large font.

There were at least 3 systems present which can be seen from the press photographs, Falcon Shield, Skyperion, AeroScope, it’s also rumoured AUDS was present.  Each system has their own approach to drone detection and varying strengths and weaknesses.  Given Gatwick now uses AUDS and Skyperion and the RAF use Falcon Shield it is clear Gatwick Airport and the RAF considered these systems to have been a success.

Gatwick Police commander Justin Burtenshaw’s was interviewed in a podcast with Philip Ingram MBE where the commander implies that the incursions stopped with the arrival of C-UAS, this contradicts the facts recorded by the DfT, by Sussex Police in their Trebor debrief and by actions Gatwick Airport took at the time.

It’s a matter of fact, the C-UAS arrived on the 20th, the airport had a suspension on the 21st from a drone sighting and the drone continued to be sighted for days afterwards.  So the C-UAS didn’t stop incursions being reported, it merely proved the visual reports were wrong.

How can anyone, looking at the facts in an impartial manner, dismiss the genuine possibility the sightings were wrong on the 19th and 20th, given C-UAS proved those on the 21st, 22nd and 23rd were wrong?  Even on the 20th there was at least one C-UAS operational while sightings were being reported, by the final sighting of that evening at 22:00 (10pm) three or more C-UAS could have been active.

On the evening of 20 December, Leonardo’s Falcon Shield was taken to Gatwick, deployed and operated by the RAF.

… and the Skyperion ES system (supplied by Lincolnshire-based Metis Aerospace).

The total policing cost of Operation Trebor was £790,208.  The Sussex Police & Crime Commissioner made an application to the Home Office for special grant funding to meet the additional costs that were incurred for the police operation, although this was rejected.

9 other police forces incurred costs for assisting in the operation as follows:

These costs were recovered from Sussex Police through the nationally recognised ‘mutual aid’ provision.  The admin fees are a standard charge of 5% levied by all forces to meet the costs of the work undertaken to provide the resources requested through mutual-aid.

The Ministry of Defence charged a token fee for the RAF presence of £1,161 that broken down as follows:
•  £910 for equipment lease
•  £111.76 for use of Mechanical Transport vehicles plus fuel
•  £139.24 for reimbursement of individuals Joint Personnel Administration claims.

* This evidence was obtained from a partner agency instead.

Information that has vanished includes a whole blog by Metis, in which they admit their system was deployed and assert the drone was within 1km of the airport.  This is likely just regurgitating the airport narrative as a range within 1km should have been within view from NPAS helicopters in the area as well as the thermal/optical camera on Falcon Shield.

• Giles York the then Sussex Police chief constable said the drone was sighted between the 19th and 20th December.  He later changed his view of the sightings to be the slightly more vague “throughout the period the airport was closed” which aligned with his deputy.
• Deputy Chief Constable Jo Shiner said the drone was sighted between the 19th and 21st December.
• The Sussex Police Twitter account reported a number of times, as late as the 27th December that the final sighting of the drone was 21:52 on the 19th while also Tweeting “we can unequivocally state between 19-21 Dec there have been numerous drone sightings.“
• The Operation Trebor Structured Debrief implies the sightings continued until at least the 23rd.

13/9/21 Drone DJ

Brendan Schulman reflects on his DJI career and the industry: A DroneDJ exclusive

15/12/21 The Register

Ex-DJI veep: There was no drone at Gatwick during 2018’s hysterical shutdown

19/12/23 Spiked Online

The truth about the Gatwick drone incident

• The Information Commissioner’s Office has ruled against Sussex Police on at least one Gatwick Freedom of Information request, yet the force continues to routinely ignore requests for information on this incident.
• Within the DfT e-mail system, there are 3,203 emails discussing Jason Tingley (then Detective Chief Superintendent) in relation to the Gatwick drone, from 19/12/2018 – 31/12/2018 .
• The rank of the 10 RAF personnel ranged from Senior Aircraftman to Wing Commander.
• Samira Shackle’s article for The Guardian investigating the Gatwick drone, was read over 1/2 million times online alone within 24 hours of being published.
• As of September 2021, there have been at least 1135 sightings of the Loch Ness monster and photos continue to be taken.

• 09/05/2024 – added “Evidence that has vanished when requested by the Freedom of Information Act” and “Freedom of Information mischief” and “Court/Tribunal actions” and “Freedom of Information handling hall of shame” and this “Updates” section.  Updated “Essential reading” and “Citations of this Gatwick page” to include Spiked Online.
• 04/06/2024 – various small updates following recent FOIAs focused on the RAF deployment and elaboration on the unit being the Defence Warning and Reporting Flight (DWaRF) and their departure on the 24th.  Added the “Complaint letters” section.