See and Avoid

Old Man

Active Member
I think that it is quite common with power-line inspection by helicopter below 400 feet. I don't know if the power companies care to notify landowners about such inspections.

Power companies maintain a utility "right of way" of "X" dimensions in width along the length of a power line installation and specify right of inspection by any method at any time. Access for them is a non issue, it's up to the adjoining land owners to adapt as necessary.

This thread has brought up a point that I think was contentious in an earlier post of mire relative to sUAS operators becoming cognizant of full scale flight regs. There's a lot that we must absolutely understand in order to fit within a system that has been in operation a long time before we started tooling around with RC models and multirotors. Most that do what we do have no concept of approach and departure corridors, approach and departure angles, pattern altitudes at general aviation airports, and the distance from runway center line that most aircraft fly at. Turbine aircraft use longer and wider approaches than piston twins, with twins still being further from center line than the vast majority of piston singles. Those are just starters and actually help with the see and avoid side of things. If you know where things are usually at you know where to start looking. OTH, the dumb student or low time private pilot circling his house at 500' AGL will always be a wild card...
 

Old Man

Active Member
This is a non issue. For most the floor of the NAS is 500' if sUAS is restricted below 400' where's the conflict? The odds of a helicopter and multi rotor running into each other is very low. Just because some buroecrate throws around buzz words like "see and avoid" doesn't mean that sUAS should be required to comply with it.

There's a misconception with the regs here. The floor of controlled airspace is generally 500' but class G airspace is pretty much uncontrolled to the surface. If habitation and population is low enough a pilot only needs to maintain an altitude high enough to permit a safe landing in the event a power unit fails. That altitude could be as low as 1' AGL if they can otherwise maintain safe separation from persons and structures. If the terrain was right, no people or structures were present, it could easily be deemed safe operation of an aircraft but your multirotor off in the distance becomes a hazard to aerial navigation. So you're out in the desert or on the ocean flying at 100' off the deck and a full scale comes blasting through an otherwise zero population/structure environment and a collision occurs. The full scale gets their knuckles rapped in the NTSB hearing and maybe a 90 day license suspension but you get stuck with all the financial liability. Something like this has already happened with a RC aerobatic aircraft flying, with permission and under the direction and supervision of the airport operator, at a fly in held at an uncontrolled field. A biplane did an unannounced and unplanned smoke on low pass over the runway and collided with the model. The modeler got all the heat while the full scale got paid for damages to his plane.
 

Bartman

Welcome to MultiRotorForums.com!!
Here's a copy of the Part 91 Federal Aviation Regulations (FAR's, another term we'll all likely become more familiar with going forward) regarding minimum safe altitudes....thanks for @Old Man; for adding to my post about altitudes....

Sec. 91.119 — Minimum safe altitudes: General.
Except when necessary for takeoff or landing, no person may operate an aircraft below the following altitudes:
(a) Anywhere. An altitude allowing, if a power unit fails, an emergency landing without undue hazard to persons or property on the surface.

(b) Over congested areas. Over any congested area of a city, town, or settlement, or over any open air assembly of persons, an altitude of 1,000 feet above the highest obstacle within a horizontal radius of 2,000 feet of the aircraft.

(c) Over other than congested areas. An altitude of 500 feet above the surface, except over open water or sparsely populated areas. In those cases, the aircraft may not be operated closer than 500 feet to any person, vessel, vehicle, or structure.

(d) Helicopters, powered parachutes, and weight-shift-control aircraft. If the operation is conducted without hazard to persons or property on the surface—

(1) A helicopter may be operated at less than the minimums prescribed in paragraph (b) or (c) of this section, provided each person operating the helicopter complies with any routes or altitudes specifically prescribed for helicopters by the FAA; and

(2) A powered parachute or weight-shift-control aircraft may be operated at less than the minimums prescribed in paragraph (c) of this section.

[Docket No. 18334, 54 FR 34294, Aug. 18, 1989, as amended by Amdt. 91–311, 75 FR 5223, Feb. 1, 2010]
 

scotth

Member
In all this FAA chatter about distance from airports, altitude limitations, alleged near misses with airliners... I fail to hear barely any conversation about potential conflicts with helicopters, operating quite legally and happily below 400' much of the time, landing off airports or on hospital heliports, or scene calls, searches, etc. And unlike a fixed wing which is likely to not care much about slicing through a phantom.. a collision with a helicopter is not going to go well. Have you looked at a helicopter route chart lately?
 

Old Man

Active Member
I think that was mentioned earlier, and a large part of the point of the dialog taking place. How we interact with full scale aviation, which includes helicopters and their various functions, combined with the principles of "see and avoid" which is fundamental to VFR flight operations. On a general level too many of us lack cognizance of how the system is supposed to function while we are focused on an apparent persecution of what we do. The question is how do we find the means to make it all come together to maintain a safe operating environment for everyone, including helicopters;) Situational awareness on our part will be extremely important for the types of aircraft and operations you mentioned, and cause for limiting some of the altitudes we might otherwise have thoughts of operating at.

Your post triggered a thought, perhaps we might consider starting a thread where the various sections of the FAR's related to flight operations and qualifications are discussed to expand our understanding of them and perhaps come up with concepts that might improve or expand them to better assist out fit into the system.
 

econfly

Member
I'm still trying to wrap my head around the logic of random heli pilots having the right to buzz my house and blame me if they hit my multirotor while doing it. Or how about this class G space where some guy in a plane can fly over my farm at 1' if he likes? I'm learning here and one thing I'm learning is that existing FAA rules make no sense to me. Now the reality is I don't see helis and planes out on the farm, but apparently that's only because they choose not to show up. I just did not realize that property owners had such limited rights over their own land even as much as a few feet in the air.
 

Old Man

Active Member
You do and you don't. Learned that one in a lawsuit by a property owner against a modeling club that flew off the land next door. A landowner has rights to privacy on their property (if the state (Oregon for example) provides for a right to privacy because the Constitution does not) and minimum noise through public nuisance/disturbing he peace laws, but property owners don't control their air space simply because they own the land underneath. Just as they typically don't own mineral rights below a depth of about 6' or so. Airspace control is totally maintained under federal aviation regulations. So you can expect the legal minimum separation requirements to be maintained at all times, generally assured that reckless and dangerous flight behavior will not be demonstrated, but if the conditions are otherwise correct that's all the assurances you have. Federal control of airspace is pretty much all encompassing, with deviations provided to law enforcement agencies. There's really nothing that could truly be classed as "uncontrolled".

The reason you don't see planes and helis blasting around a few feet off the ground is because most licensed pilots are typically a step or more above average in intelligence and invested a lot of time, money, and effort in obtaining ability to fly and a license that's pretty easy to lose. Not to mention that mistakes at low altitudes are often fatal. Flying is not inherently dangerous but mistakes and poor judgement can make it so in a hurry. Then you have the clause about endangering the lives and property of persons on the ground that an get real expensive for a pilot.
 

econfly

Member
And now I fully appreciate the importance of "see and avoid" (you all can see me learning in real time!). What I now understand is that existing manned rules leave basically zero airspace untouched, and even over private land. Add the attitude that manned aircraft trump RC/"drones" due to pilot safety and we end up in a place where no set of rules will work unless we can somehow prove that these "drones" pose no more risk to manned aircraft than kite flying or a rigourous game of lawn darts. If I had my way I would just push the manned flight up above a reasonable ceiling to make room for this new very promising tech (and to protect the rights and privacy of property owners). But if the reality is full deference to anything with a person in it from the ground up then I don't see how this ends well.
 

eskil23

Wikipedia Photographer
To "see and avoid" is no big deal as long as you fly within line of sight and maintain situation awareness regarding the surrounding airspace. But that rule works both ways. A drone must also be able to be "seen and avoided". To me that means navigation lights is a must, even at daylight. Some form of transponder would be nice too.
 

scotth

Member
I think that was mentioned earlier, and a large part of the point of the dialog taking place.

Yes - I didn't mean in this thread... more like mainstream media and FAA publications. You never hear 'heliport' which implies to the layman that you're good to go even if you're up the street from the hospital, which has a pad on the roof . And yes, a conversation specific to aircraft and airport operations, and FAR's that matter to modelers makes great sense.
 

Old Man

Active Member
If I had my way I would just push the manned flight up above a reasonable ceiling to make room for this new very promising tech (and to protect the rights and privacy of property owners). But if the reality is full deference to anything with a person in it from the ground up then I don't see how this ends well.

Great post and I'm extremely pleased to read how some of how the system was established to function is getting across. You also effectively used a sledge hammer to illustrate how joining any of the various organizations that is trying to get our message across to Congress and the FAA is the most effective tools we have to make things works.

You concept of placing a floor on manned operations with a ceiling on ours is a very good one. Of course there would need to be exceptions for manned aerial emergency services and awareness on our part of where those exceptions would be most anticipated. To do that requires that old school thinking, which is very much the domain of the FAA and NTSB, needs to be elevated with understanding of new technology and capabilities. If the FAA builds new rules using their traditional thought processes everything written to apply to us would almost prohibit everything we want to do. Those rules would be brutally expensive to comply with, like obtaining a full scale license to shoot for pay, and aircraft component certification would put everyone out of business. Certification and liability is why a new Cessna 172, designed nearly 50 years ago, costs upwards of $500,000.00. Can you envision a new 1000mm X-8 going out the door for $150.000.00 and adding additional certification for each payload you wanted to employ? Then restricting flight time to only 50% of battery capacity?

Using the current regulatory mindset that's pretty much what we'd be facing so there's tremendous need to assure the law makers have a solid understanding of the differences in aircraft. flight systems, flight capabilities, flight duration, etc, to make useful and effective law, not reactionary law. Then we have our side of the problem which I'm sorry to say revolves around the lack of responsibility some people have demonstrated. There has to be a way, and involvement by people like us, to get the message out that blasting off to see how high you can go and launching into or over crowds of people is a foolish and dangerous thing. Forums such as this and others could help with a general set of guide lines but sellers must have a sense of responsibility that encourages them to provide flight safety information to each purchaser. Lastly, and unfortunately, many of us are going to have to become familiar with the rules and regulations contained in the FAR's and AIM to become develop a better understanding of those rules that have been making our crowded airspace among the safest in the world since the 1930's. There's no reason someone in the air should have to die because someone flying a remotely piloted aircraft too small to see at distance and speed got in front of them.

As for rights and privacy of property owners I'm afraid that's a lost cause until people finally get fed up and change the way our government has been working. By far the most egregious violator of our rights and privacy is our government, at every level. Opening our airspace to sUAS has never been about the kind of aircraft we fly, but about the kind of aircraft that have been used for years overseas to establish human pattern of life and surveillance. Once that stuff begins flying here our personal privacy will be ended. We don't help the situation by posting everything about our lives and family in places like Facebook,,,,
 

eskil23

Wikipedia Photographer
Sagetech are selling Mode C and Mode S transponders for sUAS. The Mode C transponder weight 100 gram and cost $2913. The Mode S transponder weight 147 gram and cost $3578. The altitude encoder module and user interface module cost another $500 each.

http://api.ning.com/files/36zE12PBn...Te4XzB1/SagetechModeSTranspondereBrochure.pdf
http://www.sagetechcorp.com/unmanned-solutions/#.VKLr3PAALs

IMHO size, weigh and power consumption is okay, but the price is not. Has anyone found any cheaper transponder out there?
 

Bartman

Welcome to MultiRotorForums.com!!
IMHO size, weigh and power consumption is okay, but the price is not.

Those components are FAA/TSO Certified meaning they've been tested and shown to meet or exceed a Technical Standard Order as defined by the FAA.
From Wikipedia;
A Technical Standard Order (TSO) is a minimum performance standard issued by the United StatesFederal Aviation Administration for specified materials, parts, processes, and appliances used on civil aircraft. Articles with TSO design approval are eligible for use on the United States type certified products. The TSO authorization or a letter of TSO Design Approval does not necessarily convey approval for installation. See CFR Part 21 Subpart O.

As it says in the quote, meeting the TSO means the parts can be installed in certified aircraft and this is a high hurdle that involves significant expense for a manufacturer. If the FAA were to relax the requirements of the TSO or allow non-TSO parts to be used in sUAS then one could expect the price to come down.

non-TSO parts would also allow other designer/manufacturer/clones to enter the market which introduces a whole other set of problems.
 

Old Man

Active Member
I've known of the Sagetech products for quite some time, I have a box full one type in my shop, but production quantities are not high enough to permit lowering the price structure. I had spoken with some people at Sagetech about development of a miniature ADS-B out system and they mentioned such work was in progress. To be able to obtain ADS-B out for less than $5,000.00 is pretty amazing. General aviation isn't that lucky and it's a mandatory part of the aircraft in 2020.
 
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eskil23

Wikipedia Photographer
I don't think FAA/TSO certification is relevant in Europe. I also think that a "Mode A and C" transponder is sufficient for the purpose of "see and avoid". "Mode S" and ADB-S out is not really necessary for that. I think the pressure altimeter can be skipped to. The same feature can be mimicked using the GPS-altimeter.
 

Old Man

Active Member
From experience, a GPS altimeter does not report the same altitudes as a pressure altimeter. Went through that working with the military using a GPS altimeter. The two types would start a flight roughly equal if both dialed in the same way using field elevation or baro pressure but as time and distance from the take off point increased the GPS altimeter would show an altitude difference of up to several hundred feet higher or lower than the pressure altimeters used in the manned aircraft. Turned out the GPS altimeter was considerably more accurate than the pressure types when using non degraded GPS signals as provided by the military. A mathematical algorithm had to be used to "correct" the GPS altimeter during each flight to bring the two altimeter types into alignment. The military didn't care that GPS was more accurate because correcting would require changing what they used in all their aircraft. They had too many, it would cost too much, take too long, and, most importantly, the game was to be played by their rules.

I suspect a similar argument would be made when mixing it up with manned aircraft in civil airspace. Most civil aircraft use a pressure altimeter, which when following regulations, is re-set at some points during the flight when the aircraft is within 100 miles or so of a reporting station. At 18,000' MSL all pressure altimeters are re-set to 29.92 in.hG. to level the playing field at IFR flight altitudes. The actual altitude depicted may be wrong, but at least they are all wrong and reading the same. So using GPS with a lock on at least 4 satellites your altitude would be correct, theirs would be wrong, but you would get the heat. Using a non degraded GPS signal provides 3 dimensional position accuracy within a 20-50 centimeters. A pressure altimeter reads whatever the air pressure is at that location and time, which changes with weather conditions, and can vary hundreds of feet from true because of that.

As for the FAA/TSO standards, all aircraft and avionics certified in America are also certified pretty much everywhere else around the world. The U.S. set would aviation standards a long time ago. I agree that a Mode C transponder should be just fine for the job but the powers that be established that ADS-B out was going to be minimum requirement for all aircraft and made the law. A lot of pilots are not happy about it either.
 
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eskil23

Wikipedia Photographer
Frankly, I'd rather use a non-standard transponder with a not-so-accurate altitude reading than no transponder at all, just for saying "I'm right here."

The reason is to avoid incidents like the one on 4 december 2014 when air traffic to Bromma International Airport was shut down for one hour because the Air Traffic Controller had "received a rapport" of a drone in the control zone. The drone, which was flown by a commercial operator with a license, was actually north of the control zone, but Stockholm Control had no way of knowing that.
 

Old Man

Active Member
That method has worked pretty well for many years but there have been incidents where ATC failed to see the conflict relationship between aircraft and a collision occurred. One such event occurred between a commercial passenger jet and a light aircraft over the city of Cerritos, CA some years back. Aircraft flying under VFR flight rules and using a transponder simply squawk 1200 and without altitude encoding ATC only sees a lot of targets without associated altitudes moving about. The lack of altitude information requires that considerably more horizontal separation be maintained to use the airspace, and delays just about everything. Under such conditions IFR traffic is given priority since their positions are better defined and specific regulations for vertical and horizontal separation between IFR and other aircraft are quite specific.
 

FastCat Studio

chaos watcher
As was mentioned before, the logical response would be establishing a floor and ceiling for flight but there are times when those would be violated. A personal example is when I am doing aerial photography of a facility, the pilot will bring the plane down to about 300 ft. There is not a cut and dry solution for the sharing the skies ... as the capabilities of MRs grow, so will the need to have a way to educate new users. Right now there isn't really anything ; face it, the average person getting a Phantom for Christmas is not searching the internet for rules on flying the thing. The only reason why I found out information was because I was researching an article I wrote for a photography magazine.

Right now, it seems that the FAA is going to go the easy route (for the FAA that is) ... if someone is flying for commercial purposes, they have to have a pilot's license and jump thru hoops to get a waiver. I imagine most who are charging for MR aerial footage are not going to go thru those hoops and are hoping that they are too small to capture the FAA's attention. Considering the letter that I heard that the FAA sent to the national board of realtors, I think the FAA is going to start going after more people and most are not going to have the money or time to fight.
 


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