That is incredible if that is the Law the other side of the pond...... like it matters whether you are flying it commercially or as a hobby when you fly in to a paasenger jets engine!? Just to clarify the law in the UK is 400ft above take off level regardless of whether it is comercial or not. All Yuneec software here is natively set at 400 feet in the UK.
ByM,
The sky is not one big passenger jet engine. Never has been. Because one flies above 400' does not mean everyone in a manned aircraft is in peril. For long before I was born there have been no limits in the U.S. for the altitude at which an RC aircraft can be operated. In fact, our so called "national community based organization" has been sponsoring contests for several types of RC aircraft that routinely exceed 400' in altitude. They have even lobbied the government to keep their members exempt from altitude restrictions. Bear in mind they only represent the amateur segment of RC, not commercial. RC aerobatics, RC soaring, and other disciplines bust 400' by quite a margin during the competitions. People from the UK, Europe, and from all over the world come here to compete in these contests. The problem is not so much how high people fly, but where they fly too high.
We should understand the RC disciplines noted above have not contained autopilots to control them. They rely on the people flying them to maintain a visual link with them in order to maintain positive control. Those flying them spent considerable time and effort learning to fly them, recognizing that competence permitted the models they built with their own hands to survive for a long time. Most of them gathered together in different locations to fly and promote their hobby and have fun. They also gathered in groups to learn. Learning to fly was hard, you had to develop an understanding of the controls and how an aircraft's controls worked in order to fly, and it required a considerable amount of time to become successful. Mistakes frequently cause the destruction of the aircraft and those trying to teach themselves without the aid of others more often than not crashed model after model before they ever got to try their first landing. That method of learning was just too expensive to be practical, and continuously having to build another aircraft took a lot of time. Automated flight was not available for people to plunk down a few hundred or a thousand $$ that enabled flight and instant gratification.
They flew their models without posing any threat to anyone, in the air or on the ground. For the most part they still don't. Those that do share a commonality with multirotor operators; they use an aerial camera to enable them to fly at long distances. RC flying using an in flight camera had been done since the 1070's but until wing auto levelers and autopilots came into play the aircraft were kept pretty close to the take off point. If you could not see your aircraft it was in effect "out of control". How can you manually control something you cannot see?
So we have often flown high, sometimes very high, but we kept our RC aircraft in sight and generally operated them in relatively confined areas. We did and do not try to mix them with manned aircraft or near airports where conflicts are likely to occur. In essence, we have flown our RC aircraft responsibly. There was no reason to limit their altitude of flight back then, nor is there now. They are not a problem. That's not to say they have been problem free, there have been a few incidents with manned aviation. Some were caused by reckless manned aircraft pilots, others by RC flyers mixing it up with parachutists and ultralights.
The advent of the auto wing leveler and later the full autopilot, combined with the use of an in flight camera with active operator feedback, for model aviation is in my opinion, when "RC" became a problem for some. Until that time knowledge and skill were necessary to fly RC. That is not the case with multirotors since many of them can and do fly themselves. They require zero skill, no knowledge or training, and anyone can take one off the shelves and operate them. There's no peer group for people to learn from, no mandatory education and training programs available to educate them, and perhaps worse, at least in this country, is a lack of enforcement and penalty for those that operate recklessly. Having a camera fitted to a fully automated aircraft that allows them to see where the aircraft is flying from a pilot perspective, and for some a useful range that is much too far to be safe in the hands of an untrained person, is were the problems initiate.
Responsible people don't need to be limited by regulation, they take many things into consideration before taking action. That includes flying, which they do safely and responsibly. Those that are not responsible, and we see many of them in forums such as this, do not. That is where problems arise and no altitude limitation is going to curtail that. Their only concern is themselves. Some are vain beyond belief, thinking they are the center of the universe, believing the activities they engage in are interesting and important to all and therefore they want the world to see them in all that they do. They live with an attitude of "Hey, look at me" and don't give a twit for anything or anybody else. Combine their mental state with a fully automated model aircraft and we have a problem. Remove the automated model aircraft and the threat to manned aviation goes away. They would have to put more time and effort into learning how to fly than they are willing to devote. Instant gratification is their lot in life. If they can't do it now it's not worth doing so they move on to something else. Of course we have another group that is often not "part of the herd" that desperately wants to be accepted. Some of those will do pretty outrageous things to get noticed. For them any attention, even if it's bad attention, is desirable. I suppose a lot of the previous comes down to maturity.
Do we need an altitude cap? That's a question that needs to be divided in the answer. For some, absolutely, for others, no. To arbitrarily limit everyone is not the way to do things. Better would be a regulation that mandated manufacturers impose a training requirement that all had to meet before allowing the purchase of a multirotor. Develop a minimum certification standard and credential that all had to meet and present before owning and operating any automated flight system. Incorporate a means to limit a system's functionality in steps, removing limits in a graduated manner as the owners learned, with evidence of learning established though a series of system graded flight tests. Initiate enforcement actions against people that operate recklessly. The UK is doing much better in this than the U.S. Make the punishment very painful for the operator for the first offense. Jail time long enough that other financial ramifications are experienced by a violator, heavy fines, equipment impound, total forfeiture of equipment upon conviction, are things that would make many think before doing. Many don't obey the law just because there is a law, they obey because they fear the punishment.
Sorry, didn't mean to go on for so long. An altitude limit, or not, is not the problem. The problem is some of those flying automated aircraft, and manufacturers that provide them a ready made tool that permits them to do too much, too soon, with too little knowledge, and no skill, too far away.
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