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Understanding Impacts to Airports From Temporary Flight Restrictions (2020)

Chapter: Chapter 2 - Facts About Airspace Restrictions

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Suggested Citation:"Chapter 2 - Facts About Airspace Restrictions." National Academies of Sciences, Engineering, and Medicine. 2020. Understanding Impacts to Airports From Temporary Flight Restrictions. Washington, DC: The National Academies Press. doi: 10.17226/25934.
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Suggested Citation:"Chapter 2 - Facts About Airspace Restrictions." National Academies of Sciences, Engineering, and Medicine. 2020. Understanding Impacts to Airports From Temporary Flight Restrictions. Washington, DC: The National Academies Press. doi: 10.17226/25934.
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Suggested Citation:"Chapter 2 - Facts About Airspace Restrictions." National Academies of Sciences, Engineering, and Medicine. 2020. Understanding Impacts to Airports From Temporary Flight Restrictions. Washington, DC: The National Academies Press. doi: 10.17226/25934.
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Suggested Citation:"Chapter 2 - Facts About Airspace Restrictions." National Academies of Sciences, Engineering, and Medicine. 2020. Understanding Impacts to Airports From Temporary Flight Restrictions. Washington, DC: The National Academies Press. doi: 10.17226/25934.
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Suggested Citation:"Chapter 2 - Facts About Airspace Restrictions." National Academies of Sciences, Engineering, and Medicine. 2020. Understanding Impacts to Airports From Temporary Flight Restrictions. Washington, DC: The National Academies Press. doi: 10.17226/25934.
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Suggested Citation:"Chapter 2 - Facts About Airspace Restrictions." National Academies of Sciences, Engineering, and Medicine. 2020. Understanding Impacts to Airports From Temporary Flight Restrictions. Washington, DC: The National Academies Press. doi: 10.17226/25934.
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Suggested Citation:"Chapter 2 - Facts About Airspace Restrictions." National Academies of Sciences, Engineering, and Medicine. 2020. Understanding Impacts to Airports From Temporary Flight Restrictions. Washington, DC: The National Academies Press. doi: 10.17226/25934.
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Suggested Citation:"Chapter 2 - Facts About Airspace Restrictions." National Academies of Sciences, Engineering, and Medicine. 2020. Understanding Impacts to Airports From Temporary Flight Restrictions. Washington, DC: The National Academies Press. doi: 10.17226/25934.
×
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Suggested Citation:"Chapter 2 - Facts About Airspace Restrictions." National Academies of Sciences, Engineering, and Medicine. 2020. Understanding Impacts to Airports From Temporary Flight Restrictions. Washington, DC: The National Academies Press. doi: 10.17226/25934.
×
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Suggested Citation:"Chapter 2 - Facts About Airspace Restrictions." National Academies of Sciences, Engineering, and Medicine. 2020. Understanding Impacts to Airports From Temporary Flight Restrictions. Washington, DC: The National Academies Press. doi: 10.17226/25934.
×
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Suggested Citation:"Chapter 2 - Facts About Airspace Restrictions." National Academies of Sciences, Engineering, and Medicine. 2020. Understanding Impacts to Airports From Temporary Flight Restrictions. Washington, DC: The National Academies Press. doi: 10.17226/25934.
×
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Suggested Citation:"Chapter 2 - Facts About Airspace Restrictions." National Academies of Sciences, Engineering, and Medicine. 2020. Understanding Impacts to Airports From Temporary Flight Restrictions. Washington, DC: The National Academies Press. doi: 10.17226/25934.
×
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4 Facts About Airspace Restrictions 2.1 Types of Airspace Restrictions Although the focus of this project is on TFRs, there are other airspace restrictions. U.S. air- space is subject to rules set by the Federal Aviation Regulations (FARs), the Department of Homeland Security (DHS), and the Department of Defense (DoD). FARs are rules prescribed by the Federal Aviation Administration (FAA) governing all civil aviation activities in the United States. They are part of Title 14 of the Code of Federal Regulations (CFR). 14 CFR Part 99 prescribes rules for security control of air traffic. Two DHS agencies, the Department of Customs and Border Protection (CBP) and the Transportation Security Administration (TSA), work together to strengthen GA security for international flights. CBP has enacted procedures for private aircraft to send advance notice of the intended arrival or departure into or out of the United States, and to submit manifests of persons on board. DoD has worked with the FAA, CBP, and TSA to strengthen aviation security at U.S. military installations nationwide. There are several types of special use airspace (SUA) that must be avoided when flying in the United States. The following types are described in detail in the FAA’s Aeronautical Information Manual (AIM), section 3-4 [FAA 2018a]: • Prohibited areas • Restricted areas • Warning areas • Military operations areas • Alert areas • Controlled firing areas • National security areas Figure 1 shows a snapshot of SUA in the United States. Note the concentration of these regions in the western states and along the coasts. Aircraft wishing to fly through these areas must request and receive permission from air traffic control (ATC) in real time, using the contact frequency listed on an aeronautical chart. This does have an impact on flight operators, who must often file routes that are longer than routes passing through this SUA, but the effect is relatively small, and permanent, so it is accepted as simply part of the landscape. Section 3-5 of the AIM describes Other Airspace Areas; in particular, Section 3-5-3 describes TFRs, including the following excerpts [FAA 2018b]: a. General. This paragraph describes the types of conditions under which the FAA may impose tempo- rary flight restrictions. It also explains which FAA elements have been delegated authority to issue a C H A P T E R 2

Facts About Airspace Restrictions 5 temporary flight restrictions Notice to Airmen (NOTAM) and lists the types of responsible agencies/ offices from which the FAA will accept requests to establish temporary flight restrictions. The 14 CFR is explicit as to what operations are prohibited, restricted, or allowed in a temporary flight restrictions area. Pilots are responsible to comply with 14 CFR Sections 91.137, 91.138, 91.141 and 91.143 when conducting flight in an area where a temporary flight restrictions area is in effect, and should check appropriate NOTAMs during flight planning. b. The purpose for establishing a temporary flight restrictions area is to: 1. Protect persons and property in the air or on the surface from an existing or imminent hazard associated with an incident on the surface when the presence of low flying aircraft would magnify, alter, spread, or compound that hazard (14 CFR section 91.137(a)(1)); 2. Provide a safe environment for the operation of disaster relief aircraft (14 CFR section 91.137(a)(2)); 3. Prevent an unsafe congestion of sightseeing aircraft above an incident or event which may generate a high degree of public interest (14 CFR section 91.137(a)(3)); 4. Protect declared national disasters for humanitarian reasons in the State of Hawaii (14 CFR section 91.138); 5. Protect the President, Vice President, or other public figures (14 CFR section 91.141); 6. Provide a safe environment for space agency operations (14 CFR section 91.143); or 7. Protect persons or property in the vicinity of an aerial demonstration or major sporting event (14 CFR section 91.145). These demonstrations and events may include: • United States Naval Flight Demonstration Team (Blue Angels); • United States Air Force Air Demonstration Squadron (Thunderbirds); • United States Army Parachute Team (Golden Knights); • Summer/Winter Olympic Games; • Annual Tournament of Roses Football Game; • World Cup Soccer; • Major League Baseball All-Star Game; • World Series; • Kodak Albuquerque International Balloon Fiesta; • Sandia Classic Hang Gliding Competition; Figure 1. SUA in the United States. Source: sua.faa.gov.

6 Understanding Impacts to Airports From Temporary Flight Restrictions • Indianapolis 500 Mile Race; • Any other aerial demonstration or sporting event the FAA determines to need a temporary flight restriction in accordance with paragraph (b) of this section. Many outdoor baseball, football, and auto racing events today are covered by a single NOTAM providing for a 3-nm-radius TFR. A 3-nm “permanent” TFR is also in place over both Disney World in Florida and Disneyland in California. Section 91.145 is most often used for air shows. FAA Advisory Circular (AC) 91-63C also describes TFRs. In addition to the U.S. Code sections listed earlier, AC 91-63C also cites 14 CFR part 91, section 91.139, Emergency Air Traffic Rules; and 14 CFR part 99, section 99.7, Special Security Instructions. Item 5 (i.e., Protect the President, Vice President, or other public figures) on the list is the one that motivates many of the TFRs that were studied; these are known as VIP TFRs. More detail on this type of TFR can be found on the website of the National Business Aviation Association (NBAA); the following excerpt is from this website [NBAA 2018]: A TFR is a restriction on an area of airspace due to the movement of government VIPs, special events, natural disasters, or other unusual events. On any given day, there are typically several TFRs in place across the National Airspace System (NAS). Most non-VIP TFRs are small in scope, in non-critical locations, or allow for some aspect of general aviation to operate within them, albeit with some restrictions. However, some TFRs do have a significant restrictive impact on general and business aviation. The most common of these are VIP TFRs, which are issued in association with the movements of the President and the Vice President. Not quite as common are special event TFRs, such as those established each year in association with the Super Bowl or the UN General Assembly. The dimensions, timing, and level of restriction for each TFR vary. For VIP TFRs, these determinations are made by the United States Secret Service (USSS), in coordination with FAA Security. Once finalized, TFR information is typically distributed via Flight Data Center (FDC) Notice to Airmen (NOTAM) in advance of the event. For this research project, researchers will not model any impacts from military SUA, but will distinguish TFRs based on their intended purpose. Researchers will model financial impact based on the reasons for TFRs listed in Table 1. Each of these TFR types can carry a different impact. 2.2 Historical Occurrence of Airspace Restrictions Before estimating the impact of TFRs, researchers first wanted to assess when and where TFRs occur. To that end, data describing TFRs and other airspace restrictions from several previous years were gathered. Historical data about the location and duration of TFRs from the FAA, spanning the period from March 2014 to September 2018 were collected. This dataset includes 4,354 TFR notices but is known to be incomplete. Because TFR notices are not easily distinguished from other types of NOTAMs, the FAA provided the results from using a simple text-based search. Researchers received all NOTAMs containing the word “temporary,” but some of these notices do not pertain to TFRs, and some other notices that do pertain to TFRs are not included. Since late September 2018, researchers downloaded the list of current restrictions from the FAA’s TFR website [FAA TFR 2019], which is updated at least daily. Researchers devel- oped an automated script to download the notices and their associated geographic information system (GIS) files once per day. Between October 2018 and August 2019, researchers compiled a database of more than 2,200 TFR messages. Using this data, researchers analyzed historical use of TFRs, based on factors such as type, reason, location, frequency, and duration (start and end times). The FAA-provided data is incomplete; therefore, researchers analyzed the two datasets separately. Restriction Type Special Events Natural Hazards Space Operations Security VIP Movement Table 1. Reasons for TFRs.

Facts About Airspace Restrictions 7 Figure 2 shows the number of TFRs by month and by category. There is a distinct seasonality; fewer TFRs are issued during the winter months. Hazard TFRs are issued in support of fire- fighting operations more often during the summer months. Additional hazard TFRs are most commonly issued for mining and blasting and for natural gas venting or leaks. TFRs for air shows and sporting events are more common in the summer and autumn months. Space operations, which also include suborbital research rockets and amateur model rockets, vary from month to month. Most TFRs were issued only once or a few times for a given named location, but a few locations experienced recurring TFRs. Table 2 shows the top 20 locations for recurring TFRs during the period when data was collected. Over 1,000 TFRs are included in this list and account for about 42% of the total number of TFRs issued. Most of the frequently recurring TFRs are issued for security reasons and are related to ongoing military aircraft operations. Airspace near Cape Canaveral, Florida, and Kodiak, Alaska, is routinely blocked in support of rocket launch operations. TFRs for Morristown and Bedminster, New Jersey during this period are associated with special security for VIP travel. TFRs in Minnesota are commonly issued for blasting asso- ciated with mining operations. A map of the top 20 locations (not including Guam) is shown in Figure 3. The markers plotted on the map in Figure 3 reflect the size of those restricted regions, which is why the ones in New Jersey appear larger. San Angelo, Texas had the largest number of recurring TFRs. These are associated with military flight activity. Figure 4 shows the location of this TFR, with a 5-nm radius, on a map. The most frequent presidential TFRs were issued for Bedminster and Morristown, New Jersey. Both of these are plotted on the map in Figure 5. The restricted regions consist of two concen- tric circles, one with a 10-nm radius, and one with a 30-nm radius. Flight restrictions are more severe inside the 10-nm circle, known as the inner core. Most TFRs are in effect for 16 hours or less, although a few are in effect for many days or weeks. Table 3 shows the duration of TFRs (start time to end time) by percentile and category. This shows, for example, that 75% of VIP TFRs last for 3.75 hours or less. Some TFRs may include multiple start and stop times in the same NOTAM; this table was computed using the Figure 2. Number of TFRs of each type, by month.

8 Understanding Impacts to Airports From Temporary Flight Restrictions 3 Point Mugu Naval Air Station, CA Security 108 4 Cape Canaveral, FL Space Operations 72 5 Grand Forks Air Force Base, ND Security 59 6 Hibbing, MN Hazards 56 7 Andersen Air Force Base, Guam Security 52 8 Beale Air Force Base, CA Security 49 9 Libby Army Airfield, AZ Security 44 10 Keewatin, MN Hazards 41 11 Fort Wingate, NM Hazards 40 12 Eielson Air Force Base, AK Security 28 13 Morristown, NJ VIP 26 14 Ely, MN Hazards 19 15 Kodiak, AK Hazards 17 16 Bedminster, NJ VIP 16 17 Los Angeles, El Centro, CA Air Shows / Sports 16 18 Macon, GA Security 15 19 Brownsville, TX Hazards 14 20 Oxnard, CA Security 13 Rank TFR Location Type Count 1 San Angelo, TX Security 244 2 Corpus Christi, TX Security 111 Table 2. TFR count by location, October 2018–August 2019. Figure 3. Top 20 recurring TFR locations, October 2018–August 2019.

Facts About Airspace Restrictions 9 Figure 4. Typical security TFR issued for San Angelo, TX. overall start and stop times for the NOTAM, so some TFR may include periods where opera- tions were permitted. The wide variation with which such NOTAMs are formatted precluded an automated analysis based on common patterns for start and stop times. Each NOTAM was considered to represent a separate TFR for the purpose of this analysis. TFRs for VIP travel are typically the shortest, with more than half lasting less than 4 hours. Figure 6 breaks down the FAA-supplied data by type for each month. Researchers attempted to categorize these based on the text of the NOTAM message, which was successful for all but about 200 NOTAMs out of more than 4,300 total. Figure 6 shows a similar seasonal pattern to the daily list of TFRs collected since October 2018 (previously shown in Figure 2). VIP notices tend to be more numerous in the summer and fall. Total TFRs are more numerous in the summer and include a larger number of hazard notices as well as air shows and sporting events. Space operations vary considerably from month to month. The largest number of TFRs were issued for security reasons and account for a third of these TFRs. Nearly all of these referenced National Defense Airspace and defined airspace for military use. The second most common type of TFR was for hazards, representing about 29% of the total. The most common type of hazard (about 28% of hazard TFRs) was for blasting operations

10 Understanding Impacts to Airports From Temporary Flight Restrictions Figure 5. Typical VIP TFRs for New Jersey. Percentile VIP Security Hazards Space Operations Air Shows/Sports All Types 5 % 1.25 3.00 1.00 1.17 1.50 1.00 25 % 3.25 12.00 5.00 1.50 22.75 4.00 50 % 3.75 17.00 42.24 3.00 50.17 16.00 75 % 5.75 23.98 743.69 8.48 72.75 88.78 95 % 66.66 168.00 1634.43 58.30 80.66 1432.06 Table 3. TFR duration (hours), October 2018–August 2019, by type. associated with mining or demolition. The next most common hazard TFR (21% of total hazard TFRs) was for firefighting, followed by gas pipeline venting (13%t). The most common TFR in the FAA-provided dataset (Table 4), issued more than 400 times during this period, affects Libby Army Airfield in southern Arizona, which is a mixed-use facility that shares its runways with Sierra Vista Municipal Airport (FHU). In addition to FHU traffic, the military operates a number of unmanned aircraft system (UAS) flights. These are discussed in Section 3.5.4.

Facts About Airspace Restrictions 11 0 20 40 60 80 100 120 140 160 180 Mar 2014 Dec 2015 Mar 2016 Jun 2016 Sep 2016 Dec 2016 Mar 2017 Jun 2017 Sep 2017 Dec 2017 Mar 2018 Jun 2018 Sep 2018 AIR SHOWS/SPORTS SPACE OPERATIONS HAZARDS SECURITY VIP Figure 6. TFR types by month, FAA historical data. Rank TFR Location Type Count 1 Libby Army Airfield, AZ Security 437 2 Grand Forks Air Force Base, ND Security 339 3 Corpus Christi, TX Security 325 4 San Angelo, TX Security 282 5 Hibbing, MN Hazards 210 6 Beale Air Force Base, CA Security 148 7 Andersen Air Force Base, Guam Security 127 8 Wilmington, DE VIP 67 9 Parsons, KS Hazards 58 10 Ely, MN Hazards 48 11 Atigun Pass, AK Hazards 45 12 Hanover, MA Hazards 44 13 New York, NY VIP 31 14 20 Miles South of Boise, ID Space Operations 29 15 Morristown, NJ VIP 27 16 Indianapolis, IN VIP 26 17 Kennedy Space Center, FL Space Operations 26 18 Ft. Wingate, NM Hazards 26 19 El Centro, CA Air Shows / Sports 24 20 Gallup, NM Hazards 19 Table 4. Number of TFRs issued by top 20 locations (March 2014–September 2018).

12 Understanding Impacts to Airports From Temporary Flight Restrictions Based on the data from the past several years, researchers expect future TFRs to follow these same patterns. Security TFRs are issued frequently, but occur consistently in the same locations. Hazard TFR locations are more unpredictable. VIP TFR locations are predictable, but will change whenever a new president or vice president takes office. The VIP TFRs listed in Table 4 include locations frequented by both the presidents and vice presidents during this time period, 2014–2018. The standard size of a TFR issued around the Vice President’s location—when he is away from Washington, D.C.—is a single ring with a radius of 3nm. This size ensures a much lower impact for these TFRs; the area is 100 times smaller than the 30-nm-radius TFR issued for the president. Because of this, researchers focused primarily on VIP TFRs issued for presidential travel. 2.3 Presidential Travel History Researchers compiled a history of presidential travel; detailed information is available for recent years, and fairly good records are available going to back to 2001. Appendix A contains a complete list of domestic presidential travel in 2016 and 2018. A TFR would have been issued for every one of these trips. Many presidential visits last just a couple of hours; a few involve overnight stays, and some last for a weekend and occasionally longer. The duration and frequency of the TFRs associated with these trips are key determinants of their economic impact. For 2018, as detailed in Appendix A, the president made 103 domestic trips, spending a total of 1677 hours on the ground at those locations in 31 states. However, 78 of the trips were less than 8 hours in duration, with 2–3 hours the most common duration. Six trips lasted between 12 and 24 hours; the remaining 19 lasted 36 hours or longer. All of these long trips were to either Florida or New Jersey, except for one to New York City and one 2-night stay in Arizona. Although the travel records are incomplete at times, in 2016 the president made at least 59 domestic trips, totaling 1475 hours, as detailed in Appendix A. The duration of these also skewed toward short trips: 37 (62%) were under 8 hours, most being 2–4 hours. There were two trips over 2 weeks, and a couple of multi-day stays in California. There were 22 trips with an overnight stay, including one 3-night stay in New York. Presidential trips from 2001–2009 usually began and ended on the same day; with multiple stops in the same day. Longer duration stays were usually in Crawford, Texas. From this we can conclude that any president will make several dozen short-term domestic trips in any given year, and 5–10 overnight domestic trips on official business. Less predictable are the longer stays that are usually at least partially vacation time. These are also the trips that have a greater impact from their associated TFRs. The location of these TFRs will be driven by the identity, history, and travel preferences of each president. 2.4 Restrictions Near Washington, D.C. Following the terrorist attacks on September 11, 2001, air travel near Washington, D.C., was severely restricted. After lengthy negotiations, the present system was established, featuring concentric rings centered on Washington, D.C. (see Figure 7). These restrictions, while tech- nically a form of “temporary” flight restriction, are now considered permanent. Operations in the inner ring, known as the flight restricted zone (FRZ), are more restrictive. The FAA has established procedures under which pilots undergo pre-screening in order to fly in or out of one of the three GA airports inside the FRZ. These airports—College Park (CGS), Washington Executive (W32), and Potomac Airfield (VKX)—are known as the “Maryland 3” or sometimes

Facts About Airspace Restrictions 13 the “DC 3.” Stakeholders in New Jersey and Florida have asked that similar procedures be created to allow them to operate during VIP TFRs. The flight restrictions imposed by the FRZ have had a severe effect on air traffic at these three airports. Compared to 1990s traffic levels—before 9/11—operations at both Washington Execu- tive and College Park are down over 90% [Heck 2009]. The owner of Washington Executive has considered selling the property to a real estate developer. The procedures for security vetting have been made easier to comply with over the years, but many pilots still avoid these airports. Figure 7 shows other airports in the Washington, D.C., region. In addition to the Maryland 3, inside the FRZ are two military airfields, Andrews Air Force Base (ADW) and Davison Army Airfield (DAA), and Ronald Reagan Washington National Airport (DCA). GA flights into DCA are permitted, but they must follow stringent security procedures. A cutout in the FRZ allows Freeway Airport (W00) to operate under less restrictive conditions. The VIP TFRs in New Jersey and Florida have recurred 5–10 times per year since 2017, and businesses there report financial pressure. The Maryland 3 airports represent an extreme case. It is not quite like a full-time TFR, because the rules governing operations are slightly different. The hassle of completing the pre-screening process and then following the flight procedures carefully are a deterrent. These factors are not present with TFRs. Figure 7. Washington, D.C., Air Defense Identification Zone (ADIZ) and FRZ [FAA 2007].

14 Understanding Impacts to Airports From Temporary Flight Restrictions The airspace restrictions around Washington, D.C., eliminate the need for VIP TFRs most of the time. Whenever the president or vice president is in Washington, D.C., there is no additional impact on aviation because the ADIZ and FRZ already provide sufficient security. VIP TFRs only occur when they travel outside the Washington, D.C., area. 2.5 Restrictions Used in Other Countries This study focuses only on airports in the United States; nevertheless, researchers briefly investigated procedures used in other countries for the sake of comparison. Each country has its own airspace procedures that it employs for security and other reasons. NOTAMs are issued worldwide, and some countries issue restrictions analogous to TFRs. As one example, Canada hosted the Group of Seven (G7) Summit in Charlevoix, Quebec, on June 8–9, 2018. Canada made temporary changes to the airspace structure in the vicinity from June 1 to June 10. Figure 8 shows the structure of these restrictions, which is similar to the 10-nm and 30-nm rings used for VIP TFRs in the United States. When the United States issues TFRs for areas close to an international border, the restricted area generally does not cross over that border. For example, the standard 3-nm radius of TFRs around major outdoor sports stadiums is truncated for Detroit Tigers games so it does not extend into Canada (see Figure 9). Figure 8. Temporary airspace restrictions for G7 summit in Canada, June 2018 [Transport Canada 2018].

Facts About Airspace Restrictions 15 Figure 9. Sporting event TFR in Detroit with restricted region truncated at Canadian border (Source: SkyVector).

Next: Chapter 3 - Impacts of Airspace Restrictions »
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Temporary Flight Restrictions (TFRs) can be implemented for several reasons, including security, hazards, space operations, special events, and VIP travel. VIP TFRs, specifically presidential TFRs, have much greater impact than other types of TFRs because they encompass a larger geography, are longer in duration, and may have little advance notice.

The TRB Airport Cooperative Research Program's ACRP Research Report 224: Understanding Impacts to Airports From Temporary Flight Restrictions identifies financial and other ramifications of TFRs on airports and aviation-related businesses.

Also included as part of the report is an electronic tool that will estimate the financial ramifications of a TFR for a specific airport or related business. Further, a video was created that shows how to use the spreadsheet, with instructional voiceovers explaining its features.

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