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Final Report on 2021 Police Drone Collision with Cessna - A Very Interesting Analysis

Is it usual to mention things like that in investigations into collisions?
Yes.
If this was an incident report in my own field (education), mentioning that someone didn't see something would imply that they should have seen it. And listing it first in the findings would imply that it was the most important factor.
You might infer that, but it is not implied. In fact the opposite was expressly stated.
I read the report before I watched Don's video, and I had the same reaction to item 1 in the findings (3.1). I also noted that in item 3 the report reiterated that the RPAS pilot was likely task saturated (as mentioned earlier in the report), but item 1 didn't mention that the drone was likely below the visual acuity of the pilots and hard to spot in urban clutter (which was also mentioned earlier).
The findings referenced the factors noted in the analysis:

2.1 Collision avoidance and visual scanning​

The pilots aboard the Cessna were operating according to established circuit procedures and were on a standard final approach profile to Runway 15. To reduce conflicts with other traffic in the vicinity, they were broadcasting their location on the airport’s mandatory frequency, and monitoring the frequency for transmissions from other aircraft. The pilots did not hear any other traffic on the frequency and were not aware of any traffic in the area.​
In addition to monitoring the frequency, the Cessna pilots were using the principles of see-and-avoid as they flew the circuit, and they were actively scanning the area. By the time the 2 aircraft were in close proximity, the RPA was directly in front of the Cessna as the Cessna descended on final approach. This meant that the relatively small RPA would have been almost stationary if viewed from the Cessna cockpit and set against a complex background of urban buildings and ground features. The small size of the RPA may have resulted in a visual cue that was smaller than the visual acuity threshold of the Cessna pilots’ eyes, and the absence of background contour between the black RPA and the urban landscape would have made the RPA very difficult to see, even if the flight crew had been aware of its presence.

In both engineering (which I think Don is and I was) and education (which I am in now) if something is in the body of a report but not in the findings or action items it is basically buried and will be ignored.
Anyone who cannot be bothered to read the entire report is not the target audience.
 
As a former holder of a PPL, and driver of bug smashers, I can’t believe that they would find fault with the pilot on final, you have enough to do without looking for drones. It hard enough to see other light aircraft in the circuit.
My thoughts.
Regards
I also flew 172's and there no way that u would see the drone. Interesting that the "operator/ police" were fined, but no amount was given! Totally the drone pilots fault!!
 
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Also we have to keep in mind that; (as mentioned in the video), the agency that produced that report does not assign blame or prosecute, their mission is to determine what went wrong and make recommendations on how to avoid in the future.
Interesting...then why did they fine the drone pilot "police" and never report the amount. Totally the drone operators fault and yes I flew 172's.BS to me!!
 
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In my Post I said

"Also we have to keep in mind that; (as mentioned in the video), the agency that produced that report does not assign blame or prosecute, their mission is to determine what went wrong and make recommendations on how to avoid in the future."


Interesting...then why did they fine the drone pilot "police" and never report the amount. Totally the drone operators fault and yes I flew 172's.BS to me!!
They, (the TSB) did not levy any fine, and in my post that you quoted, I was responding to another post. You'll have to search to find out which agency levied the fine but I was speaking to the report and the agency's function in making it.

That said, I am in total agreement with most here, The Cessna Pilot could not have seen the drone and the incident was completely the fault of the Police agency and their UA pilot in my opinion. ;)
 
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RobertP said,
"On the bright side, this has given me an idea for a physics assignment: have the students work out the maximum distance the Matrice would have been visible (based on visual acuity and drone size) and how much reaction time the pilots would have had (based on their speed)"

Also visual contrast IF the view of the Drone was not physically blocked by the instrument panel. Keep in mind though, that the 172 was on final, so was slow, which means the angle of attack was high. That, combined with the high instrument panel of the 172 may mean that the line of sight from the pilot to the drone was physically blocked by the 172 itself (same problem the P63 and B17 had earlier this month). If that was indeed the case, it would have been impossible for the student or instructor to see the drone no matter their visual acuity.
 
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Anyone who cannot be bothered to read the entire report is not the target audience.
I'll defer to you on that. As I said, it's not my field.

What I'm trying to explain (and apparently not very successfully) is how an outsider reading the report could interpret it differently.

In my old engineering job, and my more recent education one, the way the findings section (3) is presented would imply that the investigators placed some of the responsibility on the Cessna pilot, not matter what was in section 2. Mentioning something in the body but not the summary is a way of saying that it isn't as significant -- so mentioning the RPAS pilot's task overload but not the Cessna pilot's visual acuity would have been a deliberate decision to assign more responsibility to the Cessna pilot without explicitly saying that. Leaving a mention of visual acuity and clutter out of the summary would have been a deliberate decision to convey that.

Intellectually I understand that this report isn't trying to imply that. But I'm fighting three decades of experience in a different field and so have to make an effort to try to read the report without looking for a subtext that isn't there.

For reference, I read the entire report, and did so before watching any videos or reading any comments about it. But based on decades of experience in a different field, I got a different impression.

I'll note that this isn't a problem that only applies to TSB reports. When switching from engineering to education I had to relearn what vocabulary meant (same word, different meaning). Code-switching is a real problem.
 
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RobertP said,
"On the bright side, this has given me an idea for a physics assignment: have the students work out the maximum distance the Matrice would have been visible (based on visual acuity and drone size) and how much reaction time the pilots would have had (based on their speed)"

Also visual contrast IF the view of the Drone was not physically blocked by the instrument panel. Keep in mind though, that the 172 was on final, so was slow, which means the angle of attack was high. That, combined with the high instrument panel of the 172 may mean that the line of sight from the pilot to the drone was physically blocked by the 172 itself (same problem the P63 and B17 had earlier this month). If that was indeed the case, it would have been impossible for the student or instructor to see the drone no matter their visual acuity.
As a physics assignment, that doesn't matter as much. I'm thinking maximum distance and reaction time, ignoring little things like could they even pick the black drone out of the urban clutter.

From a physics instruction standpoint, I'm looking at combining two units (kinematics and optics) into an assignment that requires a bit of research (visual acuity and resolution) with a real-world connection.
 
On the bright side, this has given me an idea for a physics assignment: have the students work out the maximum distance the Matrice would have been visible (based on visual acuity and drone size) and how much reaction time the pilots would have had (based on their speed).
Only if they see it.

Trust me, as a pilot and flight instructor, it is sometimes difficult to spot another aircraft that is moving, when below the horizon line. To stop a stationary mostly black drone below the horizon line is next to impossible while in a high workload environment as in the final landing phase. No pilot expects to have something that small, right in their approach line to touch down. And no pilot should ever have to worry about such a thing.
 
Half a mile at best and no reaction time. So where do these reports of drone sightings while flying come from?
If above the horizon and you are flying slowly and it passes very close to you, then it is possible to see a drone. Just like you can see a near miss with a bird as it suddenly flashes past or over your aircraft. But if you are descending and travelling at 200MPH+ then it is almost impossible to say what that fraction of a second spot was, that flashed past.
 
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The most prominent thing to me in this report was that NO ONE had vlos on this drone .... makes me feel better about some of my bush flying where I lost sight of it ....
 
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Trust me, as a pilot and flight instructor, it is sometimes difficult to spot another aircraft that is moving, when below the horizon line. To stop a stationary mostly black drone below the horizon line is next to impossible while in a high workload environment as in the final landing phase.
No argument there. Bloody difficult (if not impossible) and not their responsibility.

I'm envisioning (no pun intended) a multi-stage problem. First figure out the maximum range to see the drone (as a speck). Then figure out the maximum range to recognize it as a drone (assuming no clutter etc.). Then try to account for clutter, distractions, etc. Problem starts as simple optics with a bit of physiology (estimated diameter of pupil based on lighting conditions) and ends up in human factors.

A related (and easier) problem would be how far away the drone could be seen from the ground against a clear sky. Would it have been possible for the visual observer to see it if he'd been looking? (It was over 700 m away horizontally, and 120 m vertically.)

The physics part is relatively straightforward: just a matter of getting the correct data from the report and making reasonable assumptions. I'm curious how the students handle that, and even more curious how they try to account for some of the human factors (like picking out the drone in a cluttered environment). Less concerned about the final answer than their approach to successively refining their solutions.

I've attached a view of the approach from Apple Maps, with 3D enabled and the approximate crash location (as given in the report) marked with a pin, to give an idea of the visual clutter. Both Leslie Street and Highway 404 are pretty busy, so they would have a lot of moving vehicles that don't show on the map.
 

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No argument there. Bloody difficult (if not impossible) and not their responsibility.

I'm envisioning (no pun intended) a multi-stage problem. First figure out the maximum range to see the drone (as a speck). Then figure out the maximum range to recognize it as a drone (assuming no clutter etc.). Then try to account for clutter, distractions, etc. Problem starts as simple optics with a bit of physiology (estimated diameter of pupil based on lighting conditions) and ends up in human factors.

A related (and easier) problem would be how far away the drone could be seen from the ground against a clear sky. Would it have been possible for the visual observer to see it if he'd been looking? (It was over 700 m away horizontally, and 120 m vertically.)

The physics part is relatively straightforward: just a matter of getting the correct data from the report and making reasonable assumptions. I'm curious how the students handle that, and even more curious how they try to account for some of the human factors (like picking out the drone in a cluttered environment). Less concerned about the final answer than their approach to successively refining their solutions.

I've attached a view of the approach from Apple Maps, with 3D enabled and the approximate crash location (as given in the report) marked with a pin, to give an idea of the visual clutter. Both Leslie Street and Highway 404 are pretty busy, so they would have a lot of moving vehicles that don't show on the map.
The video shows the drone started on one street and moved to the other street moving from one side of the runway centerline to the other. He shouldn't have been anywhere in that area. Also, planes landing and taking off can easily transition 200m of altitude without any problem.
 
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The video shows the drone started on one street and moved to the other street moving from one side of the runway centerline to the other. He shouldn't have been anywhere in that area. Also, planes landing and taking off can easily transition 200m of altitude without any problem.
The report shows the police pilot launching from the York Region Maintenance Facility at Major Mac and Highway 404, heading south on Via Renzo then basically doing a clockwise quarter-circle until a bit past Leslie. (I think I should have had the pin a bit farther west, over Cassandra Crescent.) Check pages 6 and 7 of the report for the full description.

Lots of rules broken. Location, lack of communication, lack of visual observer, more than 500 m from pilot…
 
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".Would it have been possible for the visual observer to see it if he'd been looking? (It was over 700 m away horizontally, and 120 m vertically.)"

Probably yes. In my younger days my eyes were 20/12 and 20/15. I could look down on a golf course and see golf balls from 400 m up.
 
The Transportation Safety Board has released its final report regarding a collision between a police drone and a Cessna in 2021, as the Cessna made its final approach into Buttonville Airport. In this video, Don Joyce provides a fascinating analysis of the incident and the report. In the video, Don does mistakenly refer to the airport as "Buttonwood", but his analysis is solid.

I have over 700 hrs. Piloting a 172. No way the pilot was going to see this drone, and since it was below the nose of the aircraft, zero chance.

The only way the pilot could have had some responsibility is if a NOTAM had been issued for the airport advising of drone operation in the area. Even then, avoidance at approach speed by the aircraft would have been impossible. Simply put, the pilot and passenger could have easily been severely injured or killed. The fault lies with the drone operator 100%. In my opinion, the report is pure garbage.
 
A clear case of negligence on the part of York Region Police as documented at time 5:15 through 5:40 of Don's video. Lets hope they modify their procedures and start setting the standard instead of lowering it.
"With great power comes great responsibility" ~ Uncle Ben
 
If I had been the 1 to write that report, I would have listed the items in terms of decreasing factor of causation, i.e., the most influential 1 at the top, & then decreasing from there.
 
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I'll beat this dead horse further. What an embarrassment! I'm ignorant of Canadian right-of-way laws but surely a UAV must yield to manned aircraft. Didn't the Matrice alert the remote pilot that there is an aircraft in the area via ADS-B? Was that warning ignored? At the very least I hope the Cessna 172 owner was fully compensated for the damages to his aircraft and given a written apology. I realize it was an accident but If I did that I'd probably go to jail and I would deserve it!
 
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