Source: https://aviation.stackexchange.com/questions/37310/can-i-choose-whether-hobbyist-or-part-107-rules-are-more-advantageous-when-flyin
Timestamp: 2019-04-26 12:45:11+00:00

Document:
According to the FAA's UAS getting started page, if I'm flying a drone for fun within a 5 statute mile radius of an airport, I need to contact the airport and any air traffic control tower before flying. As a Part 107 pilot, I can fly a drone in class G airspace up to 400 ft AGL (or over a structure) without having to contact anyone.
I have a current Part 107 remote pilot license. To me, this makes my ability to fly a drone more flexible.
If I want to fly for fun within 5 miles of an airport and the airspace is class G, I can decide I'm flying as a Part 107 remote pilot and then I don't have to contact ATC or the airport.
If I want to fly for fun within a surface non-class-G area, I can decide that I'm a flying as a hobbyist and contact ATC and the airport if I'm within the 5-mile airport radius, no airspace authorization necessary. This is a no-go if ATC says no, but otherwise a lot faster than applying to the FAA for a waiver to fly in controlled airspace.
In either case, I would ensure that I'm not anywhere near other air traffic, and that I fly safely.
When I'm flying for fun, can I pick and choose as to whether I fly as a hobbyist or a Part 107 pilot?
The simple answer to your question is yes. If you meet all qualifications to fly either under §101 or §107, you may elect to operate under either part.
(a) Except as provided in paragraph (b) of this section, this part applies to the registration, airman certification, and operation of civil small unmanned aircraft systems within the United States.
(3) Any operation that a remote pilot in command elects to conduct pursuant to an exemption issued under section 333 of Public Law 112-95, unless otherwise specified in the exemption.
Assuming that your aircraft and operation meets the applicability requirements of §101, you could elect to operate under that part. One reason for this is due to the fact that some of the applicability requirements for operating under §101 are elective. All of those applicability requirements are found in 14 CFR 101.1 and 101.41.
(e) When flown within 5 miles of an airport, the operator of the aircraft provides the airport operator and the airport air traffic control tower (when an air traffic facility is located at the airport) with prior notice of the operation.
You could elect to not fly the sUAS strictly for hobby or recreational use. Likewise, you could elect to not operate in accordance with a community-based set of safety guidelines or within the programming of a nationwide community-based organization. If you did so elect, you would then be subject to §107.
1 To my knowledge there are no air carriers operating or authorized to operate sUAS at this time. I could be mistaken. I understand that this provision prepares the way for a future with air carriers operating sUAS in accordance with other authorizations. Think Amazon delivering packages, etc.
Note: This answer does not address what it means for an aircraft to be flown strictly for hobby or recreational use. Nor does this answer address any requirements to be met in order to operate in accordance with a community-based set of safety guidelines or within the programming of a nationwide community-based organization. Nor does this answer address how the FAA will interpret the prohibition against endangering the NAS, such as if operating over the objections of FAA air traffic or airport operators. Nor does this answer address the operational requirements of §107.
So, it's your decision. But as always, ask yourself first how you would justify that decision to the FAA if something goes wrong. As a certificated pilot, you actually have something to lose if the FAA decides to take action against you.
I had actually asked the FAA this very question in the late summer of 2016 by email. The answer is yes, of course, and I agree with both the good answers already given. I just wanted to add a minor point: If you choose to fly a particular flight under Part 107 instead of Part 101, it's not enough that you're personally certified for Part 107, the aircraft you use on the flight must also be specifically registered under Part 107.
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