Maximum Effort Avoidance of a Low-Flying Manned Aircraft

[Kilrah]

The drone is at 200 feet AGL. A helicopter suddenly appears over the treetops at 150' AGL and it's flight path is taking it toward a point directly under the drone. It arrives just as your drone descends vertically through 150'

Flying the drone laterally while descending might have averted contact.

Except in real life you won't know it's at 150', nor even whether it's actually above or below, especially if you have only a second to take a decision.

I'm remembering being taught to fly a Cessna 150 that when the engine sputters, you immediately reach for the fuel selector to be sure it's on both tanks, pull the carburetor heat on, and set the mixture to full. The instructor had me practice so that it was an automatic thing and there was no need to think or look around for the right levers and knobs. I think it's worth developing that sort of near-reflexive response to a sudden and immediate collision threat.

And that is precisely why "down" is the correct answer, just like this it is an action that is not dependent on circumstances and doesn't require/leave options for thinking with the associated delay and risk of error/confusion. You were taught to "set on both", not "look at the gauges, check which one is empty, turn the knob the correct way" because it'd delay the response and you might get the knob to the wrong side by getting confused in the action. Trying to figure out if it's above or below, left or right is that thing you need to think about and don't want.

 

[BobaFut]

I don't think I've ever had a super close call, but there have been times where I was flying legally and had a helicopter pop up in the general vicinity of where I was flying and I thought it was below 400ft...my strategy here is obviously to descend, but I always aim for the nearest structure or trees or other tall obstacle, since my assumption is that any manned aircraft will be maximizing their distance from them. For example, I was flying at about 300ft around the WV State Capitol, and a TV helicopter came down the river. I could see it on FlightRadar24, which I had running on my tablet and it looked like it was headed for my position quickly. So rather than trying to descend and worrying about avoiding the buildings and trees below me, I just moved my drone closer to the capitol dome where I knew the helicopter likely wouldn't go and just hovered there until the helicopter exited the area.

 

[MS Coast]

Except in real life you won't know it's at 150', nor even whether it's actually above or below, especially if you have only a second to take a decision.


And that is precisely why "down" is the correct answer, just like this it is an action that is not dependent on circumstances and doesn't require/leave options for thinking with the associated delay and risk of error/confusion. You were taught to "set on both", not "look at the gauges, check which one is empty, turn the knob the correct way" because it'd delay the response and you might get the knob to the wrong side by getting confused in the action. Trying to figure out if it's above or below, left or right is that thing you need to think about and don't want.

We agree that defining an emergency response is wise and that practicing the response is a good idea. We agree that "down" is the best course of action in most cases with a manned aircraft very near the drone and that's generally understood by drone pilots.

But down in Sport mode is much better than down in Cine or Normal mode.

So, would it not be good to make "Left stick full back, Sport mode on." the practiced response?

 

[old man mavic]

what would be the benefit of practicing a response ,that would not necessarily be the best course of action in every different scenario ,just get out of the way, the best way you can,all you need is the knowledge of what is expected of you ,if such an encounter were to happen

 

[GregS]

So, what is the best maneuver for maximum-effort avoidance of a low-flying manned aircraft that appears suddenly near our drone and presents a clear and present collision hazard? Surprisingly I don't recall seeing this specifically addressed in any instructional videos or publications.

I'm thinking that collision avoidance maneuvers are something we need to sort out prior to needing to execute them. Knowing how to respond appropriately is essential. And removing even a second from our response time might make be the difference between a collision and a near miss.

I'll toss this out as a starting point for discussion, with the assumption that the manned aircraft is at or above the drone's altitude.

An immediate movement of the left stick full back and the right stick fully in a direction perpendicular to the aircraft's flight path, along with a switch to sport mode.

It might be worth practicing to work out how to execute all three motions on the controller quickly and develop some dexterity.

Comments?

If not flying beyond VLOS, you should be able to hear an aircraft coming and descend immediately. I fly near a Naval Air Station with low flying training aircraft waaaay below 500'. I can hear them coming a long time before they are near me. I am allowed to fly up to 200' AGL. Never been an issue.

 

[MS Coast]

what would be the benefit of practicing a response ,that would not necessarily be the best course of action in every different scenario ,just get out of the way, the best way you can,all you need is the knowledge of what is expected of you ,if such an encounter were to happen

Better response time. Reduced possibility of incorrect response. Better outcome in an imminent collision situation.

(Again, I'm talking about situations where there's an immediate threat of collision.)

When that Cessna engine sputters and quits when you're running on the left tank, your hand needs to go automatically to the fuel selector switch and move the lever straight up and down for Both. You don't want to fumble for where the selector is or read the marks to see where the Both position is. It's a time to react, not analyze and then react. Sure, the problem might possibly be simultaneous failure of both magnetos, but it's almost always fuel starvation.

My only closer-than-I'd-like-to-be encounter with a manned aircraft came a few months after I began flying a Mini 2. My girlfriend/VO and I were sitting on a rock jetty with the Mini 2 over the beach and a parking area. There were wave sounds and an noisy shrimp boat leaving the harbor. A very low and fast flying USCG helicopter got within 150 yards before we were aware of it. I immediately pulled the left stick back, as I'd learned from reading and watching instructional videos. (And exercising plain common sense.) The helicopter was turning and passed between me and the drone at about 200' AGL. The drone was below 40' AGL at the closest point of approach.

I was in Cine mode. In the excitement of that big noisy orange and white helicopter so close, it didn't occur to me to switch to Sport mode. Now, after thinking about close encounters and a little practice, I'm programmed to pull the left stick full back and slide the mode switch full right without having to think about it.

 

[JDubyaM]

As a manned helicopter pilot for 25 years, SOP ( standard operating practice) was for collision avoidance, both pilots are to deviate their path to the right. Everything else, descent, climb, speed reduction are all secondary decisions, first and foremost. Turn Right!
Part 91.113(e).

 

[dart106]

Depending on the flight path vector, the fastest move 90 degrees away form the approaching threat.

 

[Yorkshire_Pud]

Depending on the flight path vector, the fastest move 90 degrees away form the approaching threat.

In terms of the speeds available that is possibly correct but the point of many of these posts is that that only works if you instantly know that the drone is in the plane's flight path, which is unlikely.
If the drone IS NOT in the plane's flight path then panic horizontal movement perpendicular to the plane's perceived flight path could move the drone into the plane's flight path. So too could vertical movement but down is arguably the lesser evil and, I think, the most likely to reach safety asap.

 

[Dale D]

So, what is the best maneuver for maximum-effort avoidance of a low-flying manned aircraft that appears suddenly near our drone and presents a clear and present collision hazard? Surprisingly I don't recall seeing this specifically addressed in any instructional videos or publications.

I'm thinking that collision avoidance maneuvers are something we need to sort out prior to needing to execute them. Knowing how to respond appropriately is essential. And removing even a second from our response time might make be the difference between a collision and a near miss.

I'll toss this out as a starting point for discussion, with the assumption that the manned aircraft is at or above the drone's altitude.

An immediate movement of the left stick full back and the right stick fully in a direction perpendicular to the aircraft's flight path, along with a switch to sport mode.

It might be worth practicing to work out how to execute all three motions on the controller quickly and develop some dexterity.

Comments?

My driveway is my testing grounds, but every evening ,as the sun is setting , there is a lot of low flying traffic over my house coming and going to a local airport miles away from me. Some of these are small planes but mostly helicopters. I can hear them before I see them. They all seem definitely under 400 feet. I have learned to by hyper acute about being ware of the sounds first and rapid pull down the iron on the left stick.

Dale

 

[Torque]

I live 3.5 miles west the Auburn, WA municipal airport. This airport is down in the valley, I'm up on the hill above it, both airplane pilots and heli pilots train out of this airport, so I get a lot of traffic overhead. 11.5 miles NW of me is Seatac International Airport, depending on the commercial flight path that day, and my proximity above the small airport, the sound of small planes or helicopters are sometimes masked until they are right over me. I've never had a close call yet.
I fly with an FAA approved strobe and PRACTICE evasive maneuvers to avoid a panicked response. I work in healthcare where safety drills are simply a part of our culture, whether facility or patient related, we practice repeatedly and attempt to plan for all the variables. I use that same philosophy when it comes to safety in other aspects of my life.
Sport mode descent and yup, usually lateral movement is my most practiced maneuver.

 

[MAvic_South_Oz]

I live 3.5 miles west the Auburn, WA municipal airport. This airport is down in the valley, I'm up on the hill above it, both airplane pilots and heli pilots train out of this airport, so I get a lot of traffic overhead. 11.5 miles NW of me is Seatac International Airport, depending on the commercial flight path that day, and my proximity above the small airport, the sound of small planes or helicopters are sometimes masked until they are right over me. I've never had a close call yet.
I fly with an FAA approved strobe and PRACTICE evasive maneuvers to avoid a panicked response. I work in healthcare where safety drills are simply a part of our culture, whether facility or patient related, we practice repeatedly and attempt to plan for all the variables. I use that same philosophy when it comes to safety in other aspects of my life.
Sport mode descent and yup, usually lateral movement is my most practiced maneuver.

Do you think these small manned aircraft you see are flying below 500' ?
Do they seem to ever be as low as your drones max 400' AGL decree ?
And do you have any flight altitude restrictions (below 400') that are often in place if you are in any flight approach / departure areas ?

Most airports here (and I'm sure in most countries) have thought all this separation business out between manned aircraft and other UAV / model type craft.
Of course one always needs to be vigilant in any airspace, but normally below 500' seems very close to the ground for any manned flights, bar landing / ground ops like ag spraying, special tourism flights etc, and most pilots want to keep as high as practical for obvious reasons (mech failure reaction ability, bird strikes and the likes).

 

[dart106]

In terms of the speeds available that is possibly correct but the point of many of these posts is that that only works if you instantly know that the drone is in the plane's flight path, which is unlikely.
If the drone IS NOT in the plane's flight path then panic horizontal movement perpendicular to the plane's perceived flight path could move the drone into the plane's flight path. So too could vertical movement but down is arguably the lesser evil and, I think, the most likely to reach safety asap.

Downward is also an option to move 90 degrees from the flight path. Obviously the “right move” is purely situationally dependent. Also, if the drone pilot has effective situational awareness, theres no need for a panic move, just a controlled change in flight path. There are endless “what if” scenarios with all, dependent on situational awareness.

 

[JDubyaM]

Do you think these small manned aircraft you see are flying below 500' ?
Do they seem to ever be as low as your drones max 400' AGL decree ?
And do you have any flight altitude restrictions (below 400') that are often in place if you are in any flight approach / departure areas ?

Most airports here (and I'm sure in most countries) have thought all this separation business out between manned aircraft and other UAV / model type craft.

One would think that's the case, but sadly no. Way back when the UAS regs were being proposed, I submitted comments to the FAA pointing out that I as a Commercial helicopter pilot , by regulation am allowed to operate under Part 135 with passengers on board as low as 300' AGL, while the UAS ceiling proposed ( and adopted) is 400' AGL. Figure out that logic!

 

[AlanL]

One would think that's the case, but sadly no. Way back when the UAS regs were being proposed, I submitted comments to the FAA pointing out that I as Commercial helicopter pilot , by regulation am allowed to operate under Part 135 with passengers on board as low as 300' AGL, while the UAS ceiling proposed ( and adopted) is 400' AGL. Figure out that logic!

This isn't a piece of info I saw while studying for the 107 exam

 

[Big Bro]

This isn't a piece of info I saw while studying for the 107 exam

I agree, this is a useful bit of info! Here's the regulations:

§ 135.203 VFR: Minimum altitudes.
Except when necessary for takeoff and landing, no person may operate under VFR—

(a) An airplane—

(1) During the day, below 500 feet above the surface or less than 500 feet horizontally from any obstacle; or

(2) At night, at an altitude less than 1,000 feet above the highest obstacle within a horizontal distance of 5 miles from the course intended to be flown or, in designated mountainous terrain, less than 2,000 feet above the highest obstacle within a horizontal distance of 5 miles from the course intended to be flown; or

(b) A helicopter over a congested area at an altitude less than 300 feet above the surface.

 

[Ty Pilot]

I think it is misleading and dangerous for a remote pilot (or any pilot for that matter), to think that we have a block of the NAS below 400 feet AGL in class G that belongs to us and that manned aircraft that stray under that minimum, somehow have a duty to avoid US. They Don't.

I recently saw several posts, as well as others for years that seem to hold onto this belief. I think it is important to keep perspective and that is we (UA's) must yield to, and avoid; any and all, manned aviation - in ALL airspace -All the time.

We should also keep in mind that; like a 107 pilot, they (manned aviation) can deviate from any regulation they have on the books in order to secure safety of their aircraft, crew, passengers and property.

§ 107.21 In-flight emergency.​

(a) In an in-flight emergency requiring immediate action, the remote pilot in command may deviate from any rule of this part to the extent necessary to meet that emergency.

(b) Each remote pilot in command who deviates from a rule under paragraph (a) of this section must, upon request of the Administrator, send a written report of that deviation to the Administrator.

 

[Kilrah]

somehow have a duty to avoid US. They Don't.

They don't, but they also have a legal minimum alt for a reason and if they go below it outside of an emergency they are consciously choosing to endanger themselves, potential presence of UAVs obviously not being the only reason. They're also more likely to encounter birds, have reduced time to respond to emergencies, less overall situational awareness,,...

 

[Ty Pilot]

They don't, but they also have a legal minimum alt for a reason and if they go below it outside of an emergency they are consciously choosing to endanger themselves, potential presence of UAVs obviously not being the only reason. They're also more likely to encounter birds, have reduced time to respond to emergencies, less overall situational awareness,,...

Thats not our problem. As far as we are concerned, we just have to watch out for and avoid them regardless. Debating the legality of flights that should or should not be where they are, only serves as a distraction from our job as UA PIC's.

 

[MS Coast]

I agree, this is a useful bit of info! Here's the regulations:

§ 135.203 VFR: Minimum altitudes.
Except when necessary for takeoff and landing, no person may operate under VFR—

(a) An airplane—

(1) During the day, below 500 feet above the surface or less than 500 feet horizontally from any obstacle; or

(2) At night, at an altitude less than 1,000 feet above the highest obstacle within a horizontal distance of 5 miles from the course intended to be flown or, in designated mountainous terrain, less than 2,000 feet above the highest obstacle within a horizontal distance of 5 miles from the course intended to be flown; or

(b) A helicopter over a congested area at an altitude less than 300 feet above the surface.

But, if someone violates those provisions, UAS (drone) operators must still give way to them. Manned aircraft always have the right of way.