I’ve provided many updates on the FAA program to decommission about one-third of the VOR network in the Continental U.S. That VOR Minimum Operational Network (MON) will leave 589 VORs in operation by FY2030.
FAA recently hosted a webinar to update aviators on the program. You can watch the video below.
Here’s a link to the most recent update on the VOR MON:
Latest on VOR Decommissioning (May 2021)
See also:
Here’s the latest information about the FAA program to decommission about 34 percent (307) of the VOR navaids in the U.S. by fiscal year 2030, leaving 589 VORs in the system. That plan includes establishing a minimum operational network (MON) of navaids and airports. The details are in an update (PDF) delivered at the April 26-29, 2021 session of the Aeronautical Charting Meeting.
You can find more information about the FAA plan in previous updates here at BruceAir:
You can also watch video of an FAA webinar about the MON program on YouTube:
Here’s a summary of the next sets of VORs to be shut down. To see the VOR locations on aeronautical charts at SkyVector.com, click the navaid ID links.
Discontinue six (6) VORs – June 17, 2021:
Discontinue six (6) VORs – August 12, 2021:
Discontinue five (5) VORs – October 7, 2021:
FAA also plans to expand the service volumes of the remaining VORs and DMEs to support the MON.
FAA continues its program to decommission about 307 (34%) of the VORs in the continental U.S. Some 589 VORs (with enhanced service volumes) will remain operational when the minimum operational network (MON) program is complete, now scheduled for FY2030.
At the October 2020 session of the Aeronautical Charting Meeting, Ernesto Etienne, VOR MON Lead Engineer at FAA, provided an update on the program to date.
For more information about the MON program, see: Updated VOR Retention List, Next Round of VOR Shutdowns, VOR Status–Another Update, Minimum Operational Network (MON) Airports.
As of September 20, 2020, FAA had shut down 82 VORs. In Phase 2 of the program, which runs through FY2030, another 225 navaids will be decommissioned.
The 82 VORs discontinued as of September 30, 2020 are in this list (PDF).
Through the end of calendar year 2020, the following navaids are scheduled to be shut down (to see these VORs on a chart at SkyVector, click the links).
Five (5) VORs planned for discontinuance – November 5, 2020:
The FAA publishes lists of airports that have ILS and VOR approaches designated as backups if the GPS system is disrupted. These MON (minimum operational network) airports are part of FAA’s plans to decommission about 30% of the existing network of VORs by 2025. The MON airports are not the only airports that offer ILS or VOR approaches. But the procedures at MON airports do not include PBN elements (i.e., GPS).
As the FAA’s MON program website notes:
The VOR MON is further designed to allow aircraft to proceed to a MON airport where an ILS or VOR approach procedure can be flown without the necessity of GPS, DME, ADF, or Surveillance. Of course, any airport with a suitable instrument approach may be used for landing, but the VOR MON assures that at least one airport will be within 100 NM.
The AIM adds:
Any suitable airport can be used to land in the event of a VOR [sic: GPS] outage. For example, an airport with a DME−required ILS approach may be available and could be used by aircraft that are equipped with DME. The intent of the MON airport is to provide an approach that can be used by aircraft without ADF or DME when radar may not be available.
AIM 1-1-3 (f)
Lists of MON airports are sorted by state, which can be misleading at first glance. The state boundaries aren’t especially important–the intent is to provide a MON airport within 100 nm. And even if a widespread GPS outage occurs, you could probably get ATC assistance to find a suitable airport with weather above LIFR minimums. MON airports are truly “last resort” airports.
MON airports are shown on IFR en route charts. See New Airport Info on FAA IFR Charts. More information about the VOR MON program and MON airports is in AIM 1-1-3 (f) VHF Omni-directional Range (VOR). See also this Charting Notice from May 28, 2019.
You can find lists of current MON airports in the Chart Supplement (formerly called the A/FD) books for various regions of the U.S. For example, here is the list of MON airports in the Northwest.
The June 20, 2019 update to the Aeronautical Chart User’s Guide explains the new MON designator added to basic airport information displayed on IFR enroute charts
The new label is added to airports that are part of the VOR Minimum Operational Network plan that FAA is implementing as it gradually decommissions about 30 percent of the existing VOR network. (To review the latest update on the MON plan, see Next Round of VOR Shutdowns here at BruceAir.)
Effective June 20, 2019, IFR US Enroute Charts will symbolize VOR Minimum Operational Network (MON) airports with the
designator placed above the airport name in reverse negative text. The intent of the MON designation is to alert pilots, in the event of a GPS outage, of those airports that have retained ILS and VOR instrument approach procedures for safe recovery during such an outage.
More information about the VOR MON program and MON airports is in AIM 1-1-3 (f) VHF Omni-directional Range (VOR):
The VOR MON will retain sufficient VORs and increase VOR service volume to ensure that pilots will have nearly continuous signal reception of a VOR when flying at 5,000 feet AGL. A key concept of the MON is to ensure that an aircraft will always be within 100 NM of an airport with an instrument approach that is not dependent on GPS…If the pilot encounters a GPS outage, the pilot will be able to proceed via VOR-to-VOR navigation at 5,000 feet AGL through the GPS outage area or to a safe landing at a MON airport or another suitable airport, as appropriate.
At the April 24-25, 2019 session of the Aeronautical Charting Meeting, FAA noted that the following VORs will be decommissioned in 2019 (to see each VOR on a VFR chart at SkyVector.com, click the links below):
1. [ASP] Au Sable, in Oscoda, MI – June 20, 2019
2. [CSX] Cardinal, in St. Louis, MO – June 20, 2019
3. [LSE] La Crosse, in La Crosse, WI – June 20, 2019
4. [MTO] Mattoon, in Mattoon/Charleston, IL – June 20, 2019
5. [BQM] Bowman, in Louisville, KY – Aug. 15, 2019
6. [CZQ] Clovis, in Fresno, CA – Aug. 15, 2019
7. [FRM] Fairmont, in Fairmont, MN – Aug. 15, 2019
8. [GRV] Grantsville, in Grantsville, MD – Aug. 15, 2019
9. [GTH] Guthrie, in Guthrie, TX – Aug. 15, 2019
10. [HUB] Hobby, in Houston, TX – Aug. 15, 2019
11. [IKK] Kankakee, in Kankakee, IL – Aug. 15, 2019
12. [ISQ] Schoolcraft County, in Manistique, MI – Aug. 15, 2019
13. [TPL] Temple, in Temple, TX – Aug. 15, 2019
These shutdowns are part of FAA’s Minimum Operational Network (MON) plan to decommission 311 (about 35%) of the existing VOR network by 2025, leaving some 585 VORs in operation. As of early June 2019, 42 VORs have been shut down.
You can review the latest update from the MON program office here (PDF) and find general information in AIM 1−1−3. VHF Omni−directional Range (VOR), paragraph f. The VOR Minimum Operational Network (MON).
More details about the FAAs plans are available at BruceAir: VOR Status–Another Update
A key part of the MON program is increasing the service volume of remaining VORs to 70 nm at 5000 AGL, as described in the program update.
FAA provided another update on its plans to reduce the VOR network at the October 2018 meeting of the Aeronautical Charting Meeting. The latest Very High Frequency Omnidirectional Range (VOR) Minimum Operational Network (MON) Program update (PDF) includes the following key details:
As I’ve noted in several previous posts (e.g., here), the VOR MON program is designed to provide backup to GNSS (GPS). Specifically, within the contiguous United States the MON program will support conventional navigation in the event of a GPS outage by ensuring that pilots can:
MON airports (i.e., those with conventional instrument procedures as described above) will be identified on en route charts, FAA Chart Supplements, and included in the National Airspace System Resource (NASR) Subscriber File data set for developers of electronic charts, apps, and so forth.
The FAA’s detailed policy for the transition was outlined in the Federal Register, here. More information about the program to reduce the VOR neworks is available at AOPA, here.
Here’s the list of next round of VORs scheduled to be shut down. I have provided links to the navaids at SkyVector.com so that you can see each location on a sectional chart. Note that in each case, several nearby VORs will remain in service:
BUU (BURBUN) Burlington, WI – Nov. 8, 2018
RUT (RUTLAND) Rutland, VT – Nov. 8 2018
VNN (MT VERNON) Vernon, IL – Nov. 8, 2018
TVT (TIVERTON) Tiverton, OH – Nov. 8, 2018
CSX (CARDINAL) St. Louis, MO – Jan. 3, 2019
ISQ (SCHOOLCRAFT CO) Manistique, MI – Jan. 3, 2019
MTO (MATTOON) Mattoon, IL – Jan. 3, 2019
ORD (CHICAGO O’HARE) Chicago, IL – Jan. 3, 2019
RID (RICHMOND) Richmond, IN – Jan. 3, 2019
FRM (FAIRMOUNT) Fairmont, MN – Feb. 28, 2019
GNP (GLENPOOL) Tulsa, OK – Feb. 28, 2019
LSE (LA CROSSE) La Crosse WI – Feb. 28, 2019
MTW (MANITOWOC) Manitowoc, WI – Feb. 28, 2019
GTH (GUTHERIE) Guthrie, TX – Apr. 25, 2019
HUB (HOBBY) Hobby, TX – Apr. 25
CZQ (CLOVIS) Clovis, in Fresno, CA – Apr. 25, 2019
The FAA has updated its plans to shut down about 311 VORs (about 30% of the existing network of 873 navaids) by 2025. About 585 VORs will remain in the minimum operational network (MON).
I went through the list of VORs that have been shut down and those scheduled to be decommissioned through September 2018. This PDF includes links to each navaid at SkyVector so that you can see them on a chart.
Note that in all cases, several nearby VORs remain active. Some of the VORs retain the DME feature and remain named fixes that you can file and use (with GPS–or DME).
The primary impact of the shutdowns would seem to be VOR-based approaches and perhaps departure procedures. Low altitude Victor airways, where necessary, are being supplanted with T-routes.
As the slide below shows, most of the VORs set to be decommissioned are in the Eastern and Central regions; only 15 navaids in the Western region are on the list.
To see the full list of VORs on the shutdown list, visit this entry at BruceAir. For more information about the process that FAA follows, see this explanation at AOPA. More information is available in the FAA Navigation Programs Strategy (PDF).
At the April 25-26, 2018 meeting of the Aeronautical Charting Forum (complete meeting minutes as PDF here), a representative of the VOR MON Program Office described progress on the plan (full presentation as PDF here). Here are some highlights:
The FAA plans to increase the standard service volume (SSV) of the VORs that remain in the MON. Specifically, SSV at 5000 AGL will increase from the present 40 nm to 70 nm to support IFR navigation during a GPS outage. The following slides compare VOR coverage under the current standard with coverage using the new SSV.
Here’s the list of VORs that have been decommissioned so far:
Here’s the list of the VORs scheduled for shutdown by the fall of 2018:
At the October 2017 meeting of the Aeronautical Charting Forum, the FAA provided an update on the program gradually to decommission about 309 VORs by 2025 as part of the switch to GNSS-based performance based navigation (PBN).
To see the full list of VORs that FAA plans to decommission, visit this post at BruceAir.
According to the minutes of that meeting and a presentation from an FAA representative, the switch to the mininimum operational network (MON) of about 587 VORs includes the following highlights:
Discontinued 16 VORs to date:
– [EDS] Edisto, in Orangeburg, SC – February 4, 2016
– [BUA] Buffalo, in Buffalo, SD – July 21, 2016
– [PNN] Princeton, in Princeton ME – July 21, 2016
– [PLB] Plattsburgh, in Plattsburgh, NY – September 15, 2016
– [AOH] Allen County , in Lima, OH – September 15, 2016
– [ABB] Nabb, in Nabb Indiana – January 5, 2017
– [SYO] Sayre, in Sayre Oklahoma – April 27, 2017
– [ENW] Kenosha, in Kenosha Wisconsin – June 22, 2017
– [BTL] Battle Creek, in Battle Creek, Michigan – June 22,2017
– [HRK] Horlick, in Horlick Wisconsin – June 22, 2017
– [HUW] West Plains, Missouri – August 17, 2017
– [RIS] Kansas City, Missouri – September 14, 2017
– [DDD] Port City, in Muscatine, IA – October 12, 2017
– [JKS] Jacks Creek, TN – October 12, 2017
– [MXW] Maxwell, CA – October 12, 2017
– [STE] Stevens Point, WI – October 12, 2017
Over the next six months, the following seven VORs are scheduled to be shut down:
– [AOO] Altoona, PA
– [BRD] Brainerd, MN
– [DKK] Dunkirk, NY
– [HVN] New Haven, CT
– [PNE] North Philadelphia, PA
– [RNL] Rainelle, WV
– [RUT] Rutland, VT
You can follow the links in the list above to see the VORs on a VFR chart. Note that these navaids are not the only VORs in the vicinity. In fact, in most cases, at least one VOR is within just a few miles of the facility slated for shutdown.
Part of the switch to the MON is establishing new VOR service volumes. The FAA representative noted that upgrading and flight checking remaining VORs is one the next steps in the VOR MON program. The upgraded service volume values will be 70 nm at or above 5000 ft and 130 nm above 18,000 ft for high VORs. When the flight checks are complete, new information about VOR service volumes will be published in the Chart Supplement and the AIM.
At the October 26-27, 2016 meeting of the Aeronautical Charting Forum, FAA provided an update on its plans to decommission VORs as the aviation world transitions to performance based navigation (PBN) predicated on GPS.
AOPA provided an update on the FAA’s plans for VORs and the minimum operational network (MON) on October 31, 2017. You can read the news item here. You can learn more about the plans to reduce the number of VORs at this blog, here.
A discussion of the MON appears in AIM 1-1-3. VHF Omni-directional Range (VOR):
f. The VOR Minimum Operational Network (MON). As flight procedures and route structure based on VORs are gradually being replaced with Performance−Based Navigation (PBN) procedures, the FAA is removing selected VORs from service. PBN procedures are primarily enabled by GPS and its augmentation systems, collectively referred to as Global Navigation Satellite System (GNSS). Aircraft that carry DME/DME equipment can also use RNAV which provides a backup to continue flying PBN during a GNSS disruption. For those aircraft that do not carry DME/DME, the FAA is retaining a limited network of VORs, called the VOR MON, to provide a basic conventional navigation service for operators to use if GNSS becomes unavailable. During a GNSS disruption, the MON will enable aircraft to navigate through the affected area or to a safe landing at a MON airport without reliance on GNSS. Navigation using the MON will not be as efficient as the new PBN route structure, but use of the MON will provide nearly continuous VOR signal coverage at 5,000 feet AGL across the NAS, outside of the Western U.S. Mountainous Area (WUSMA).
NOTE−
There is no plan to change the NAVAID and route structure in the WUSMA.The VOR MON has been retained principally for IFR aircraft that are not equipped with DME/DME avionics. However, VFR aircraft may use the MON as desired. Aircraft equipped with DME/DME navigation systems would, in most cases, use DME/DME to continue flight using RNAV to their destination. However, these aircraft may, of course, use the MON.
1. Distance to a MON airport. The VOR MON will ensure that regardless of an aircraft’s position in the contiguous United States (CONUS), a MON airport (equipped with legacy ILS or VOR approaches) will be within 100 nautical miles. These airports are referred to as “MON airports” and will have an ILS approach or a VOR approach if an ILS is not available. VORs to support these approaches will be retained in the VOR MON. MON airports are charted on low−altitude en route charts and are contained in the Chart Supplement U.S. and other appropriate publications.
NOTE−
Any suitable airport can be used to land in the event of a VOR outage. For example, an airport with a DME−required ILS approach may be available and could be used by aircraft that are equipped with DME. The intent of the MON airport is to provide an approach that can be used by aircraft without ADF or DME when radar may not be available.2. Navigating to an airport. The VOR MON will retain sufficient VORs and increase VOR service volume to ensure that pilots will have nearly continuous signal reception of a VOR when flying at 5,000 feet AGL. A key concept of the MON is to ensure that an aircraft will always be within 100 NM of an airport with an instrument approach that is not dependent on GPS. (See paragraph 1−1−8.) If the pilot encounters a GPS outage, the pilot will be able to proceed via VOR−to−VOR navigation at 5,000 feet AGL through the GPS outage area or to a safe landing at a MON airport or another suitable airport, as appropriate. Nearly all VORs inside of the WUSMA and outside the CONUS are being retained. In these areas, pilots use the existing (Victor and Jet) route structure and VORs to proceed through a GPS outage or to a landing.
3. Using the VOR MON.
(a) In the case of a planned GPS outage (for example, one that is in a published NOTAM), pilots may plan to fly through the outage using the MON as appropriate and as cleared by ATC. Similarly, aircraft not equipped with GPS may plan to fly and land using the MON, as appropriate and as cleared by ATC.NOTE−
In many cases, flying using the MON may involve a more circuitous route than flying GPS−enabled RNAV.(b) In the case of an unscheduled GPS outage, pilots and ATC will need to coordinate the best outcome for all aircraft. It is possible that a GPS outage could be disruptive, causing high workload and demand for ATC service. Generally, the VOR MON concept will enable pilots to navigate through the GPS outage or land at a MON airport or at another airport that may have an appropriate approach or may be in visual conditions.
(1) The VOR MON is a reversionary service provided by the FAA for use by aircraft that are unable to continue RNAV during a GPS disruption. The FAA has not mandated that preflight or inflight planning include provisions for GPS− or WAAS−equipped aircraft to carry sufficient fuel to proceed to a MON airport in case of an unforeseen GPS outage. Specifically, flying to a MON airport as a filed alternate will not be explicitly required. Of course, consideration for the possibility of a GPS outage is prudent during flight planning as is maintaining proficiency with VOR navigation.
(2) Also, in case of a GPS outage, pilots may coordinate with ATC and elect to continue through the outage or land. The VOR MON is designed to ensure that an aircraft is within 100 NM of an airport, but pilots may decide to proceed to any
appropriate airport where a landing can be made. WAAS users flying under Part 91 are not required to carry VOR avionics. These users do not have the ability or requirement to use the VOR MON. Prudent flight planning, by these WAAS−only aircraft, should consider the possibility of a GPS outage.NOTE−
The FAA recognizes that non−GPS−based approaches will be reduced when VORs are eliminated, and that most airports with an instrument approach may only have GPS−or WAAS−based approaches. Pilots flying GPS− or WAAS−equipped aircraft that also have VOR/ILS avionics should be diligent to maintain proficiency in VOR and ILS approaches in the event of a GPS outage.
BruceAir, LLC 