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Air Traffic Services Process Brief -- Tall Towers: The FAA's Obstruction Evaluation Process -- LinksAir Traffic Services Process Brief -- Tall Towers: The FAA's Obstruction Evaluation Process -- Links

Air Traffic

  • Determine a proposal's impact on aeronautical operations, air traffic procedures, and airport traffic patterns
  • If required, circularize proposal(s) and evaluate aeronautical comments before issuing a determination
  • When a proposal has an adverse aeronautical effect, negotiate with the sponsor to eliminate the problem
  • Although a determination officially comes from the regional level, the Air Traffic Office usually issues the determination.

Airports Office

  • Evaluate the proposal's effect upon existing and planned airports including: airport operations, capacity, efficiency, and development

Flight Procedures and Flight Standards

  • Evaluate the object's effect on visual flight rules (VFR) routes, VFR terminal operations, and other concentrations of VFR traffic (en route environment)
  • Determine a structure's impact to terminal area instrument flight rules (IFR) operations such as transitions, radar vectoring, holding, approaches, and arrival and departure procedures
  • Evaluate the effect of the proposed construction on en route IFR operations including minimum en route altitudes (MEAs), minimum crossing altitudes (MCAs), and minimum holding altitudes (MHAs)
  • When an effect occurs, provide a statement as to what adjustments can be made to eliminate the adverse effect.

Airway Facilities

  • Evaluate the physical and/or electromagnetic effect on the quality of navigational or communication signals
  • Assess the impact on air traffic services such as control tower line-of-sight issues, ground-based radar, sunlight reflection, etc.

Military Representatives

  • Evaluate the effect of a proposal on military airports, special use airspace, and military training routes

Frequently Asked Questions

1. Question: If the FAA is powerless to stop the construction of a tower or other tall object, why conduct an aeronautical study?

Answer: It is important to remember that the FAA is really the keeper of all airspace, and as such, is charged with balancing the needs of all airspace users. As pilots, we tend to think of ourselves as their sole customer. This of course is not the case. The FAA conducts its study to determine what, if any impact the object will have. Next, the FAA works to eliminate any hazard that might exist. Finally, the FAA needs to know of an object's existence so that it may be adequately charted.

2. Question: If the FAA is powerless to stop the construction of a tower or other tall object, what is the incentive for a proponent to comply with the notification requirements?

Answer: Although the FAA is powerless to halt construction, most towers are built to house a transmitter of some type. This requires approval from the Federal Communications Commission (FCC), who does have the regulatory power to stop construction. With a hazard determination from the FAA, the FCC will not issue the necessary building permits. Also, having a hazard determination is often helpful to airspace users when working with local zoning or land-use agencies to prevent construction.

3. Question: Who has the final say as it relates to the construction of a tall tower or other objects?

Answer: In spite of the federal government's involvement, the true power lies with local zoning boards. That is why our members are often told that these issues do not end with a FAA determination. In some cases, even states have strict provisions governing the construction of tall objects. In all cases, local zoning is a key factor in determining the disposition of a construction proposal.

4. Question: Why are so few hazard determinations issued?

Answer: The FAA often works with proponents to negotiate the height of the proposed object. If possible, proponents are often willing to reduce an object's height or find a new location that is more desirable. Also, this type of construction activity is an extremely lucrative business. Given the money making potential involved, most construction companies employ the services of experts in the OE process. This helps to eliminate many of the entanglements that could occur further along in the process.

5. Question: Once a FAA determination is issued, can I petition for a review if I disagree with the determination?

Answer: If you commented on the initial study, or the proposal was not circulated for comment, then you may petition a FAA determination. Such petitions are handled at the headquarters level within the FAA. However, if a proposal was circulated and you failed to submit comments by the deadline provided within the proposal, you essentially relinquished your right to participate in the aeronautical study. Also, keep in mind that in the event a hazard determination is issued, the proponent also has the same right to appeal.

6. Question: How do I submit comments to an aeronautical study?

Answer: When a study is circularized for comment, the contact information with the appropriate address is provided. As for format, it is best that comments be concise and directly related to the proposal's adverse aeronautical impact. Also, this will be one of several cases being worked, so be sure to address your comments to specialist cited in the circular. The study number should also be provided for quick reference.

7. Question: Of what value are my comments to an aeronautical study?

Answer: This largely depends on the validity and focus of your comments. It is important to keep in mind that the FAA is looking to evaluate the object's impact on the safe and efficient use of airspace. If your comments do not speak to this point, they will carry no weight. It is easy to become passionate, especially when you believe a tower or building poses a threat to your safety. However, avoid this pitfall and focus on the facts of the case. Doing this will not only help you, it will also help the specialist evaluating the case to better understand your issues and make a valid assessment.

8. Question: How does the FAA determine the impact of an object to planned airport activities, such as a runway expansion or the addition of an instrument approach?

Answer: If the projected changes are included as part of the airport's site file or approved airport layout plan (ALP), these improvements are treated as though they already exist. In other words, the minimums for a planed approach are protected to that same degree as those already in service.

9. Question: What is the best way to maintain vigilance in protecting my airport from construction proposals?

Answer: First, familiarize yourself with the state and local zoning laws impacting your airport of operation. Find out what governing body is responsible for making land-use decisions in your area and involve yourself to the extent possible with that group. If they hold regular meetings (and they should), be sure you attend. Finally, build a good relationship with airport management, and make sure that they forward FAA circulars to the local pilot community. Better still, form an airport support group to actively become involved with every issue of mutual concern. The more eyes and ears you have, the less likely you are to have a construction proposal slip quietly past.

FAA's regional 520 Office (Airspace Branch) Contact Information

Alaska Region (AAL)
222 West 7 th Avenue, #14
Anchorage, Alaska 99513

Anthony M. Wylie


Central Region (ACE)
901 Locust
Kansas City, Missouri 64106-2641

Bryan Burleson


Eastern Region (AEA)
159-30 Rockaway Boulevard
Jamaica, New York 11434-4848
Mailing Address:
1 Aviation Plaza
Jamaica, New York 11434-4809

Michael J. Sammartino


Great Lakes Region (AGL)
O'Hare Lake Office Center
2300 East Devon Avenue
Des Plaines, Illinois 60018

Denis Burke


New England Region (ANE)
12 New England Executive Park
Burlington, Massachusetts 01803



Northwest Mtn. Region (ANW)
1601 Lind Avenue SW
Renton, Washington 98055

Carla Mawhorter


Southern Region (ASO)
1701 Columbia Avenue
College Park, Georgia 30337
Mailing Address:
P.O. Box 20636
Atlanta, Georgia 30320

Nancy Shelton


Southwest Region (ASW)
2601 Meacham Boulevard
Fort Worth, Texas 76137-4298

Robert N. Stevens


Western-Pacific Region (AWP)
15000 Aviation Boulevard
Hawthorne, California 90261
Mailing address:
P.O. Box 92007
World Postal Center
Los Angeles, California 90009

Leonard Mobley