FAA Form 7460-1, the Notice of Proposed Construction or Alteration, is the filing you submit to tell the Federal Aviation Administration about a planned structure or change that could affect navigable airspace. You file it through the FAA’s Obstruction Evaluation/Airport Airspace Analysis (OE/AAA) portal at least 45 working days before construction starts, and the FAA then runs an aeronautical study that ends in a formal determination. The rules sit in 14 CFR Part 77, and skipping the filing when it’s required carries a civil penalty of $1,000 per day.
When You Have to File
Four situations trigger the notice requirement. Hitting any one of them is enough.
Height above 200 feet AGL. Any proposed structure taller than 200 feet above ground level at its site requires a filing, no matter where it is or how far it sits from an airport. This catches most tall towers, wind turbines, and high-rise buildings on its own.
Proximity to an airport or heliport. Structures well under 200 feet can still trigger the requirement if they penetrate imaginary sloped surfaces that rise from the runway or landing area. The slopes depend on the facility:
- Airports with a runway longer than 3,200 feet: a 100-to-1 slope extending 20,000 feet from the nearest runway. A structure 1,000 feet from the runway triggers a filing if it’s more than 10 feet above runway elevation.
- Airports with runways of 3,200 feet or shorter: a 50-to-1 slope extending 10,000 feet.
- Heliports: a 25-to-1 slope extending 5,000 feet from the landing and takeoff area.
These apply to public-use airports listed in FAA flight information publications, military airports, airports operated by a federal agency, and any airport or heliport with at least one FAA-approved instrument approach.1eCFR. 14 CFR 77.9 – Construction or Alteration Requiring Notice
On-airport construction. Any construction or alteration on a public-use airport or heliport requires notice regardless of height or where on the field it sits. A one-story shed at the far edge of the airport still needs a filing.2Federal Aviation Administration. Notification of Proposed Construction or Alteration on Airport Part 77
Highways, railroads, and other traverseways. Changes that would raise mobile objects high enough to penetrate the airspace surfaces above also require notice. The regulation adds set heights to the road or track surface: 17 feet for Interstate highways, 15 feet for other public roads, 23 feet for railroads, and the tallest normally traveling object for private roads and waterways.1eCFR. 14 CFR 77.9 – Construction or Alteration Requiring Notice
Situations That Change How You File
Cranes and Other Temporary Structures
Construction cranes and drilling derricks count as structures. If a crane at your site would exceed a notice trigger, it needs its own 7460-1, and the form asks whether the structure is permanent or temporary along with how long the equipment will be in place.3Federal Aviation Administration. Notice of Proposed Construction or Alteration – FAA Form 7460-1
Structures Over 2,000 Feet AGL
Anything above 2,000 feet above ground level is presumed by the FAA to be a hazard that causes inefficient use of airspace. The burden shifts to you: your filing must explain in detail why the project wouldn’t be a hazard and wouldn’t create airspace inefficiency.4eCFR. 14 CFR Part 77 Subpart B – Notice Requirements
Projects That Also Need FCC Licensing
If your structure needs a Federal Communications Commission license, the 7460-1 must be filed on or before the date you file the FCC application. The 45-working-day rule still applies, so you have two deadlines to track.4eCFR. 14 CFR Part 77 Subpart B – Notice Requirements
Emergencies
The 45-day advance rule is waived when immediate construction is needed for an emergency involving essential public services, public health, or public safety. You notify the FAA by any fast method available and follow up with a completed Form 7460-1 within five days.4eCFR. 14 CFR Part 77 Subpart B – Notice Requirements
Checking Whether Your Project Triggers a Filing
The FAA offers a free Notice Criteria Tool (NCT) on its website. Enter your project’s coordinates and height and the tool tells you whether you penetrate any of the airport-proximity surfaces. For the 200-foot AGL trigger, no tool is needed. If your structure exceeds 200 feet AGL, you file.
Keep AGL and MSL straight when running the numbers. AGL (above ground level) is measured from the ground at your structure’s base to its highest point. MSL (above mean sea level) adds the ground elevation to the AGL height. A 150-foot tower on a hilltop at 1,000 feet elevation is 150 feet AGL and 1,150 feet MSL. The FAA evaluates airspace penetration using the MSL figure, so both numbers matter.
Information You’ll Need for the Form
Accuracy on the form drives the whole aeronautical study. Wrong coordinates or a bad height can lead to a determination that gets revoked later, which puts your build schedule at risk. The form asks for:
- Latitude and longitude of the proposed structure, precise enough for the FAA to model its relationship to flight paths and airport surfaces.
- Height AGL, measured from ground at the base to the highest point.
- Height MSL, combining site elevation with structure height. This is the figure the FAA relies on.
- Structure type (building, antenna tower, wind turbine, crane, or other) and whether it’s permanent or temporary.
- Proposed start and completion dates.
- Supporting documents such as a plot plan, certified survey, or site map showing location relative to nearby features.
Temporary structures need an estimated duration in place. If the project also needs FCC licensing, note that on the form.
How and Where to Submit
Filing runs through the OE/AAA web portal at oeaaa.faa.gov.5Federal Aviation Administration. Obstruction Evaluation/Airport Airspace Analysis The portal handles electronic submission and runs an automated screening against the notice criteria. Paper filings exist but the FAA strongly prefers electronic submission, and the online system moves faster.
The deadline that matters: your notice must reach the FAA at least 45 working days before construction starts or before you apply for a construction permit, whichever comes first. Those are working days, not calendar days, so plan for roughly nine weeks from submission to your intended start.2Federal Aviation Administration. Notification of Proposed Construction or Alteration on Airport Part 77 Once the system accepts your filing it assigns an Aeronautical Study Number (ASN) that you use to track the case.
What the FAA Does With Your Filing
The aeronautical study looks at whether your structure would interfere with VFR and IFR operations, air traffic procedures, minimum flight altitudes, and existing or planned airports. It also evaluates physical or electronic effects on navigation, communication, and surveillance systems.6eCFR. 14 CFR 77.31 – Determinations
The review pulls in local air traffic control and military flight operations, and the FAA may open a public comment period. Minimum processing time runs about 60 days, and complex cases with multiple airports or instrument approach impacts take longer. The FAA’s guidance tells sponsors to plan on at least two months from the date the notice is received.7Federal Aviation Administration. Obstruction Evaluation/Airport Airspace Analysis If something in your filing is wrong or incomplete, the FAA contacts you, but unresolved issues can lead to the study being terminated after 30 days.
The Three Possible Determinations
No Hazard, below obstruction standards. Your structure doesn’t exceed any obstruction standard and the FAA finds no hazard. The project moves forward without special conditions.6eCFR. 14 CFR 77.31 – Determinations
No Hazard, exceeds standards but no substantial impact. The structure passes an obstruction standard but the aeronautical impact isn’t substantial enough to be called a hazard. This outcome often carries conditions: marking and lighting under Advisory Circular 70/7460-1M, supplemental notice obligations, or limits on temporary construction equipment.8Federal Aviation Administration. AC 70/7460-1M – Obstruction Marking and Lighting Those conditions are part of the determination, not optional.
Hazard to Air Navigation. A hazard determination issues when the structure both exceeds an obstruction standard and would have a substantial aeronautical impact. This is where projects stall. Practically, it means reducing height, relocating, or dropping the project.6eCFR. 14 CFR 77.31 – Determinations
What You Owe the FAA After a No-Hazard Determination
Validity and Starting Construction
A Determination of No Hazard expires 18 months after its effective date unless you begin construction within that window. Actual structural work such as laying a foundation counts; excavation alone does not. If you abandon the project before the determination expires, it terminates on the abandonment date.9GovInfo. 14 CFR 77.33 – Effective Period of Determinations
Extensions
You can petition for a one-time extension if you can’t start within 18 months. The FAA will normally grant another 18 months unless new adverse conditions have surfaced since the original determination. The request must arrive no earlier than 90 days and no later than 15 days before the determination expires, and structural work must not have started yet.10Federal Aviation Administration. Extension of Determinations If the FAA turns up new facts that block an extension, it issues a Notice of Preliminary Findings, which can lead to a revised hazard determination.11eCFR. 14 CFR 77.35 – Extensions, Terminations, Revisions and Corrections
Supplemental Notice
For structures taller than 200 feet AGL, or when the FAA specifically asks, you must file a supplemental notice on Form 7460-2 to report construction progress. If the determination gives a deadline, follow that deadline. Otherwise you have five days after the structure reaches its greatest height. You also owe the FAA notice within five days if the project is abandoned, dismantled, or destroyed.4eCFR. 14 CFR Part 77 Subpart B – Notice Requirements
Penalties for Not Filing
Skipping the notice when it’s required isn’t a gray area. The form itself states that anyone who knowingly and willfully violates the Part 77 notice requirements faces a civil penalty of $1,000 per day until the notice is received, under 49 U.S.C. Section 46301(a).3Federal Aviation Administration. Notice of Proposed Construction or Alteration – FAA Form 7460-1 The fine isn’t the only cost. An after-the-fact filing can push your schedule back by months while the FAA studies a structure that may already be under construction, and a hazard determination at that stage can mean tearing down what you’ve built.