Not that it’s an answer to the original question, but this thread has me wondering what the process is for turning private land into a private registered airport? If I happened to own an adequate plot of land, how would I go about getting it designated a private airport?
Part 157 requires anyone establishing, altering, or permanently closing an airport notify the government:
§ 157.3 - Each person who intends to accomplish any of the following actions must notify the FAA.
- Construct or otherwise establish a new airport or activate an airport
- Construct, realign, alter, or activate any runway or other aircraft landing or takeoff area of an airport
- Deactivate, discontinue using, or abandon an airport or any landing or takeoff area of an airport for a period of one year or more.
- Construct, realign, alter, activate, deactivate or discontinue using a taxiway associated with a landing or takeoff area on a public-use airport
- Change the status of an airport from private use or from public use to another status
- Change any traffic pattern or traffic pattern altitude or direction
- Change status from Instrument Flight Rules (IFR) to Visual Flight Rules (VFR) or vice versa
However, that regulation only applies if you call it an "airport". If you fly out of your pasture, or even a 3000'x100' patch of well manicured lawn it's not an "airfield" if you didn't formally establish it as an airfield with the FAA.
There are however some advantages to establishing your private airstrip as an "airport". It will allow the FAA to maintain your private airport in its central database of airport information. That can be very helpful in allowing the FAA to identify and resolve potential airspace problems, whether it's someone wanting to build a tower near your airport, or the FAA changing airspace in the future (for example class D being upgraded to class C and encompassing the airspace over your private strip, which could otherwise complicate life for you.
That however is also the extend of the feds being involved in regulating private airfields, so there is no downside with establishing an "airport" other than the notification requirements at § 157.3 - at the federal level.
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State involvement however can vary a lot by state. Some states have no involvement at all. Others like South Dakota have some minimum requirements:
https://sdlegislature.gov/Rules/DisplayRule.aspx?Rule=70:02:04
However, for a restricted use airports in South Dakota, the requirements are minimal if it's a restricted use airport that isn't within 2 miles of an existing airport boundary, (and then the primary concern is that no part of the traffic patterns for the runways overlap):
Application Requirements:
Before any public airport, landing field, or heliport, or any private airport, landing field, or heliport located within two miles of the nearest boundary of any approved public airport, is used or operated in the state of South Dakota, the airport, landing field, or heliport shall be licensed or approved by the commission.
Definition of restricted use landing field:
(8) "Restricted use landing field," a landing area approved by the commission for restricted use only as stated in the approval or to be used in case of emergency.
Editorial comment: Note here that having a restricted airstrips means that pilots can use it in an emergency.
Requirements for restricted use landing fields:
70:02:04:14. Minimum requirements for restricted use landing fields. Restricted use landing fields shall be of sufficient size and condition with adequate approach clearances to accommodate the type of aircraft specified to be used thereon, and the use intended thereof.
Editorial comment: Basically, if you have 600' of length and 40' of width in a clearing that is sufficient to get your XCub in and out of the clearing, it'll probably pass muster as a restricted use airstrip. However, if you crash, it by definition it does not pass muster.
If however you want a non restricted airport then there are a lot more requirements:
70:02:04:07. Minimum requirements for nonrestricted licensing or approval of airports and landing fields. All airports and landing fields, other than for restricted use only, to be eligible for approval or licensing must meet the following requirements:
(1) Each end of the runway shall have a minimum unobstructed approach zone providing a glide angle of at least 20:1. This approach zone shall be trapezoidal in shape, beginning at a point 200 feet beyond the end of the runway and extending out 5,000 feet along the extended centerline. This zone is 250 feet wide at the inner edge and 1,250 feet wide at the outer edge. The approach zone shall have a minimum clearance of 15 feet over all highways, 17 feet over interstate highways and 23 feet over railroads;
(2) No objects shall penetrate the primary or transitional surfaces. The primary surface is a horizontal plane, 250 feet wide, 125 feet on either side of the landing area centerline and at the same elevation as the centerline. The transitional surface is an inclined plane with a slope of 7:1, being 7 feet horizontal for each one foot vertical, beginning at the outer edge of the primary surface and extending upward and outward;
(3) Runway lengths listed in subdivisions 70:02:04:07(5) to (7), inclusive must be increased for site elevation at the rate of 7 percent for each 1,000 feet of elevation above mean sea level; five tenths of one percent for each degree which the mean maximum temperature of the hottest month exceeds the standard temperature of 60 degrees Fahrenheit; and 20 percent for each one percent of effective gradient;
(4) The entire landing area must be suitable for safe operation of aircraft under normal weather conditions;
(5) Airports approved by the commission prior to August 25, 1964, shall have at least one serviceable landing area of 1,600 feet in length and 100 feet usable width;
(6) Airports approved between August 25, 1964, and July 24, 1974, inclusive, shall have at least one serviceable landing area 1,800 feet in length, 100 feet usable width;
(7) Airports established or requesting approval after July 24, 1974, shall have at least one serviceable runway 2,100 feet in length, 50 feet usable width. For landing fields or turf strips the length shall be increased by 400 feet after the necessary corrections have been added and the usable width increased to 100 feet.
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The takeaway here is that while the Feds are fairly silent on the issue, you may have some state requirements that have to be met, that amy or may not involve initial and/or on going inspections. Depending on the state and their views on state preeminence, you may also encounter some very daunting county and city zoning and special use permit requirements as well. There be dragons there.