Drone spotted on approach to LHR
Jul 18, 2022, 7:30 am
#46
Join Date: Sep 2009
Posts: 2,833
Jul 18, 2022, 7:37 am
#47
Join Date: Nov 2003
Location: Here and there
Programs: AA EXP
Posts: 1,551
Jul 18, 2022, 8:48 am
#49
Join Date: Dec 2012
Posts: 3,203
For the past few years we’ve regularly had NOTAM’d the presence of a drone off the western end of the airfield that has been conducting surveying work well within those boundaries. In summer 2019 it was regularly observable in the evenings hovering just over the other side of the M25.
That drone was indeed known about and authorised.
However I myself have had a near miss with a drone as did the preceding 747. So close was it that with the Police attending both aircraft to try and locate the drone and it’s operator, plus the Mandatory Occurrence Report to the CAA, we both ended up proving further commentary and evidence to the AirProx board and both events were classified as a significant threat of collision and published by said board. This event occurred within the zone previously mentioned. This time of year and clear weather are prime elements for such events. Clear and calm weather in November is a recipe for laser attacks.
Comes the weather witch, comes the obstacles.
Other than the use of Russian style laser powered anti-drone weaponry, I can’t see much effectiveness from hinted system.
That drone was indeed known about and authorised.
However I myself have had a near miss with a drone as did the preceding 747. So close was it that with the Police attending both aircraft to try and locate the drone and it’s operator, plus the Mandatory Occurrence Report to the CAA, we both ended up proving further commentary and evidence to the AirProx board and both events were classified as a significant threat of collision and published by said board. This event occurred within the zone previously mentioned. This time of year and clear weather are prime elements for such events. Clear and calm weather in November is a recipe for laser attacks.
Comes the weather witch, comes the obstacles.
Other than the use of Russian style laser powered anti-drone weaponry, I can’t see much effectiveness from hinted system.
Jul 18, 2022, 1:02 pm
#50
Join Date: Aug 2014
Programs: BA Executive Club and OnBusiness
Posts: 721
Heathrow restricted areas and geo-fencing is one mile radius and 5 miles on approach at both runway ends. So 4 miles would likely be in. I have confidence in countermeasures as they are high level tech that shouldn't fail. And triangulation is the simplest part. 2 radio towers pin the source. Essentially the lines between each tower can pinpoint the location of the pilot
An A321 lands at around 140 knots = 160 mph. At that speed a plane covers 2.67 miles per minute (160/60), so it would cover at least 4 miles in 90 seconds and 5.3 miles in 120 seconds. That's around the edge of the protected zone and around Kew Gardens. Good luck to anyone trying to triangulate and catch a drone operator in that area. In reality a minute or two before landing the speed is a little higher (180 mph at 2 mins before touchdown according to FlightAware.com) which would increase the distance i.e. the plane would be even further away from Heathrow at 90/120 seconds before touchdown. And if the timing estimate is even just 10 seconds out it could have been 6.5 miles away from LHR.
If someone reports seeing a unicorn or a flying pig I'm going to be skeptical, (although even flying pigs in London airspace are possible https://en.wikipedia.org/wiki/Pink_Floyd_pigs), but if someone reports seeing a drone near Heathrow (backed up by reports from multiple sources - including pilots - without the airspace being immediately closed for investigations) then I think their credibility can be left unquestioned