NCGS

Geodetic News Archive

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY GPS INTERFERENCE TESTING
PATUXENT RIVER (PAXRVR) 24-01 (REVISION 1)
1 - 29 February / Patuxent River, MD

Please note that this particular test is not the typical GPS interference test that is centered at a point and impacting an expanding radius with increasing elevation like an upside-down truncated cone. Rather, this test will impact the following area from the surface to UNL (altitudes greater than 99,900FT):

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY GPS INTERFERENCE TESTING
FORT LIBERTY (formerly known as Fort Bragg) NORTH CAROLINA (FTLBNC) 24-05
22 - 29 January / Fort Liberty, NC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY GPS INTERFERENCE TESTING
FORT LIBERTY (formerly known as Fort Bragg) NORTH CAROLINA (FTLBNC) 24-01
16 - 19 January / Fort Liberty, NC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY GPS INTERFERENCE TESTING
MARINE CORPS SPECIAL OPERATIONS COMMAND NORTH CAROLINA (MSOCNC) 23-03
08 - 12 December / Holly Ridge, NC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY GPS INTERFERENCE TESTING
FORT LIBERTY (formerly known as Fort Bragg) NORTH CAROLINA (FTLBNC) 23-65
01 - 07 December / Fort Liberty, NC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY GPS INTERFERENCE TESTING
FORT LIBERTY (formerly known as Fort Bragg) NORTH CAROLINA (FTLBNC) 23-47
22 - 24 August / Fort Liberty, NC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY GPS INTERFERENCE TESTING
FORT LIBERTY (formerly known as Fort Bragg) NORTH CAROLINA (FTLBNC) 23-46
15 - 20 August / Fort Liberty, NC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY GPS INTERFERENCE TESTING
CARRIER STRIKE GROUP FOUR (CSG4) 23-03
04 July / Off-The-Coast, SC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY GPS INTERFERENCE TESTING
PATUXENT RIVER (PAXRVR) 23-02
22 May – 16 June / Patuxent River, MD

Please note that this particular test is not the typical GPS interference test that is centered at a point and impacting an expanding radius with increasing elevation like an upside-down truncated cone. Rather, this test will impact the following area from the surface to UNL (altitudes greater than 99,900FT):

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY GPS INTERFERENCE TESTING
FORT BRAGG NORTH CAROLINA (FTBRNC) 23-24
18 - 20 April / Fort Bragg, NC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY GPS INTERFERENCE TESTING
CARRIER STRIKE GROUP FOUR (CSG4) 23-01-D
27 March / Off-The-Coast, NC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY GPS INTERFERENCE TESTING
FORT BRAGG NORTH CAROLINA (FTBRNC) 23-22 (REVISION 1)
07 - 11 March / Fort Bragg, NC

FLIGHT ADVISORY GPS INTERFERENCE TESTING
CARRIER STRIKE GROUP FOUR (CSG4) 23-01-A
07 – 14 March / Off-The-Coast, SC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY GPS INTERFERENCE TESTING
FORT BRAGG NORTH CAROLINA (FTBRNC) 23-14
19 - 20 January / Fort Bragg, NC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY GPS INTERFERENCE TESTING
FORT BRAGG NORTH CAROLINA (FTBRNC) 22-57
15 - 20 September / Fort Bragg, NC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY GPS INTERFERENCE TESTING
FORT BRAGG NORTH CAROLINA (FTBRNC) 22-47 REVISION 1
19 - 21 July / Fort Bragg, NC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS INTERFERENCE TESTING
FORT BRAGG NORTH CAROLINA (FTBRNC) 22-31
07 - 12 June / Fort Bragg, NC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS INTERFERENCE TESTING
CARRIER STRIKE GROUP FOUR (CSG4) 22-03N
05 – 12 June / Off-The-Coast, SC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS INTERFERENCE TESTING
CARRIER STRIKE GROUP FOUR (CSG4) 22-02 REVISION 1
15 – 28 March / Off-The-Coast

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS INTERFERENCE TESTING
FORT BRAGG NORTH CAROLINA (FTBRNC) 22-13
08 – 10 Mar / Fort Bragg, NC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS INTERFERENCE TESTING
PATUXENT RIVER MARYLAND (PAXRVR) 22-01
25 Feb – 11 Mar / Patuxent River, MD

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS INTERFERENCE TESTING
FORT GORDON GEORGIA (FTGOGA) 22-09
14 - 16 February / Fort Gordon, GA

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS INTERFERENCE TESTING
FORT BRAGG NORTH CAROLINA (FTBRNC) 21-64
12 - 13 October / Fort Bragg, NC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS INTERFERENCE TESTING
FORT BRAGG NORTH CAROLINA
31 August - 22 September / Fort Bragg, NC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS INTERFERENCE TESTING
CARRIER STRIKE GROUP FOUR (CSG4) 21-06 S2
07 – 14 August / Off of the NC coast

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS INTERFERENCE TESTING
FORT BRAGG NORTH CAROLINA (FTBRNC) 21-37
21 – 24 June 2021 / Fort Bragg, NC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS INTERFERENCE TESTING
MARINE CORPS SPECIAL OPERATIONS COMMAND (MARSOC) 21-05
07 – 21 June 2021 / Marine Corps Special Operations Command, NC

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS INTERFERENCE TESTING
MARINE CORPS SPECIAL OPERATIONS COMMAND (MARSOC) 21-01 REVISION 2
1 – 21 March 2021 / Camp Lejeune, NC

This test will be centered at 34.527500°, -77.542778° and extend outward and upward like a bowl affecting the GPS signal 21 Nautical miles (NM) away at 50 ft Above Ground Elevation (AGL) relative to the center point’s (CP’s) ground elevation (~60 ft MSL), 80 NM away at 4,000 ft AGL, and so on. The specific time period that these tests will be conducted is posted on the announcement with the following caveat: “Each event may last the entire requested period.”

The FAA does not provide an affected radius figure of interest to remote pilots for 400 ft AGL. Based on the notice’s data, NCGS estimates this radius to be 52 NM. Since this radius is relative to the CP’s ground elevation (~60 ft), the radius needs to be extended by 5 NM for UAV operations at higher ground elevations where the combined ground elevation difference (remote site elevation – CP elevation) + UAV flight elevation approaches or exceeds 540 ft, 10 NM for 730 ft, 15 NM for 980 ft, and 20 NM for 1,320 ft. NCGS recommends adding a wide buffer (>10 NM) to any radius figure for operations near 400 ft AGL.

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS Interference Testing
CARRIER STRIKE GROUP FOUR (CSG4) 21-03 REVISION 1
CARRIER STRIKE GROUP FOUR (CSG4) 21-04
1 – 14 March 2021 / Off-The-Coast

These tests will be centered at 32.166667°, -79.666667°, which is 48 NM SSE of the CHARLESTON VORTAC (CHS) in Charleston, SC. There will be two tests each day, a narrow range test followed by a wide range test:

Date: 1 March
Narrow range test: 10:30 am EST - 11:14 am EST
Wide range test: 11:15 am EST - 12:59 pm EST

Date: 11 March
Narrow range test: 6:30 am EST - 7:14 am EST
Wide range test: 7:15 am EST - 12:30 pm EST

Date: 14 March
Narrow range test: 11:30 am EDT - 12:14 pm EDT
Wide range test: 12:15 pm EDT - 5:30 pm EDT

Please note the following caveat: “Each event may last the entire requested period.”

The narrow range test will extend outward and upward like a vase affecting the GPS signal 46 NM at 50 ft Above Ground Elevation (AGL) relative to the center point’s (CP’s) ground elevation (0 ft MSL), 109 NM away at 4,000 ft AGL, and 149 NM at 40,000 Mean Sea Level (MSL).

The broad range test will extend outward and upward like a bowl affecting the GPS signal 71 NM at 50 ft AGL relative to the center point’s (CP’s) ground elevation (0 ft MSL), 134 NM at 4,000 ft AGL, 178 NM at 10,000 ft MSL, and so on.

The FAA does not provide an affected radius figure of interest to remote pilots for 400 ft AGL. Based on each notice’s data, NCGS estimates this radius to be 72 NM for the narrow range test and 83 NM for the wide range test.

Since these radius figures are relative to the CP’s ground elevation (0 ft MSL), the radius needs to be extended by the following distances for UAV operations at higher ground elevations where the combined ground elevation difference (remote site elevation – CP elevation) + UAV flight elevation approaches or exceeds:

Narrow range test (72 NM at 400 ft AGL)
• 5 NM for 560 ft
• 10 NM for 780 ft
• 15 NM for 1,060 ft
• 20 NM for 1,410 ft

NCGS recommends adding a wide buffer (>10 NM) to any radius figure for UAV operations near 400 ft AGL.

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS Interference Testing
CARRIER STRIKE GROUP FOUR (CSG4) 21-01
17 – 27 January 2021 / Carrier Strike Group Four

This test will be centered at 30.937500°, -79.687500°, which is 101 NM ENE of the Craig (CRG) VORTAC in Jacksonville, Florida, and extend outward and upward like a bowl affecting the GPS signal 148 Nautical miles (NM) away at 50 ft Above Ground Elevation (AGL) relative to the center point’s (CP’s) ground elevation (0 ft MSL), 217 NM away at 4,000 ft AGL, and so on. These tests will be conducted daily 1200 Z - 2230 Z (7:00 pm EST – 5:30 pm EST) January 17th and January 24th - 27th with the following caveat: “Each event may last the entire requested period.”

The FAA does not provide an affected radius figure of interest to remote pilots for 400 ft AGL. Based on the notice’s data, NCGS estimates this radius to be 170 NM. Since this radius is relative to the CP’s ground elevation (0 ft MSL), the radius needs to be extended by 5 NM for UAV operations at higher ground elevations where the combined ground elevation difference (remote site elevation – CP elevation) + UAV flight elevation approaches or exceeds 540 ft, 10 NM for 720 ft, 15 NM for 940 ft, and 20 NM for 1,200 ft. NCGS recommends adding a wide buffer (>10 NM) to any radius figure for operations near 400 ft AGL.

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS Interference Testing
MARINE SPECIAL OPERATIONS COMMAND (MARSOC) 20-05
08 – 16 November 2020 / Ivanhoe, NC

This test will be centered at 34.648611°, -78.298333° and extend outward and upward like a bowl affecting the GPS signal 69 Nautical miles (NM) away at 50 ft Above Ground Elevation (AGL) relative to the center point’s (CP’s) ground elevation (~80 ft mean sea level or MSL), 123 NM away at 4,000 ft AGL, and so on. These tests will be conducted daily 0000 Z - 0600 Z (7:00 pm EST – 1:00 am EST) November 8-16 with the following caveat: “Each event may last the entire requested period.”

The FAA does not provide an affected radius figure of interest to remote pilots for 400 ft AGL. Based on the notice’s data, NCGS estimates this radius to be 90 NM. Since this radius is relative to the CP’s ground elevation, the radius needs to be extended by 5 NM for UAV operations at higher ground elevations where the combined ground elevation difference (remote site elevation – CP elevation) + UAV flight elevation approaches or exceeds 600 ft, 10 NM for 880 ft, 15 NM for 1,270 ft, and 20 NM for 1,800 ft. NCGS recommends adding a wide buffer (>10 NM) to any radius figure for operations near 400 ft AGL.

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS Interference Testing
FORT BRAGG NORTH CAROLINA (FTBRNC) 20-29
11 – 16 October 2020 / Ft. Bragg, NC

This test will be centered at 35.139444°, -79.163333° and extend outward and upward like a narrow test tube affecting the GPS signal 27 Nautical miles (NM) away at 50 ft above ground elevation (AGL) relative to the center point’s (CP’s) ground elevation (~300 ft mean sea level or MSL) plus the height of the broadcasting antenna, 30 NM away at 4,000 ft AGL, 30 NM away at 10,000 ft MSL, and so on. These tests will be conducted daily 0601 Z - 2359 Z (2:01 am EDT - 7:59 pm EDT) with the following caveat: “Each event may last the entire requested period.”

The FAA does not provide an affected radius figure of interest to remote pilots for 400 ft AGL. Based on the notice’s data, NCGS estimates this radius to be 28 NM. Due to the steepness of this curve, NCGS recommends adding a 5 NM buffer for any low altitude UAV ops and a 10 NM buffer for any UAV ops near 400 ft AGL.

Please note that the testing centered at Fort Bragg will be encompassed by the testing near Ivanhoe, NC, but the testing near Ivanhoe will be conducted at night [0000 Z - 0600 Z (8:00 pm EDT – 2:00 am EDT)].

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS Interference Testing
MARINE SPECIAL OPERATIONS COMMAND (MARSOC) 20-04
11 October – 02 November 2020 / Ivanhoe, NC

This test will be centered at 34.648611°, -78.298333° and extend outward and upward like a bowl affecting the GPS signal 69 Nautical miles (NM) away at 50 ft Above Ground Elevation (AGL) relative to the center point’s (CP’s) ground elev (~80 ft mean sea level or MSL), 123 NM away at 4,000 ft AGL, and so on. These tests will be conducted daily 0000 Z - 0600 Z (8:00 pm EDT – 2:00 am EDT) Oct 11 – 15 and Oct 27 – Nov 2 with the following caveat: “Each event may last the entire requested period.”

The FAA does not provide an affected radius figure of interest to remote pilots for 400 ft AGL. Based on the notice’s data, NCGS estimates this radius to be 90 NM. Since this radius is relative to the CP’s ground elevation, the radius needs to be extended by 5 NM for UAV operations at higher ground elevations where the combined ground elevation difference (remote site elevation – CP elevation) + UAV flight elevation approaches or exceeds 600 ft, 10 NM for 880 ft, 15 NM for 1,270 ft, and 20 NM for 1,800 ft. NCGS recommends adding a wide buffer (>10 NM) to any radius figure for operations near 400 ft AGL.

Please note that the testing centered near Ivanhoe will encompass the testing at Fort Bragg, but the testing near Fort Bragg will be conducted later in the day [0601 Z - 2359 Z (2:01 am EDT - 7:59 pm EDT)].

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS Interference Testing
NAVY WARFARE DEVELOPMENT CENTER (NWDC) 20-01 (Revision 1)
07 – 10 August 2020 / Portsmouth, VA

This test will be centered at 36.950000°, -76.308333° and extend outward and upward like a bowl affecting the GPS signal 49 nautical miles (NM) away at 50 ft above ground elevation (AGL) relative to the center point’s (CP’s) ground elevation (~7 ft MSL) plus the height of the antenna, 107 NM away at 4,000 ft AGL, and so on. The tests will be conducted daily 2130 Z - 2300 Z (5:30 PM - 7:00 PM EDT).

The FAA does not provide an affected radius figure of interest to remote pilots for 400 ft AGL. Based on the notice’s data, NCGS estimates this radius to be 60 NM. Since this radius is relative to the CP’s ground elevation, the radius needs to be extended by 5 NM for UAV operations at higher ground elevations where the combined ground elevation difference (remote site elevation – CP elevation) + UAV flight elevation approaches or exceeds 601 ft, 10 NM for 844 ft, 15 NM for 1,129 ft, and 20 NM for 1,456 ft. NCGS recommends adding a wide buffer (>10 NM) to any radius figure for operations near 400 ft AGL.

Users of the NCGS Geodetic Control Database (https://ncgs.nc.gov/geodeticmonuments) may notice some intermittent outages. NCGS is aware of the issue and is working to resolve it as quickly as possible.

In the meantime, users may want to try accessing the database via a different browser, and/or users may try a hard refresh to force the browser to fully reload the database page. On most browsers a hard refresh can be accomlished by pressing CTRL+F5, but users should consult their browser help resources for exact instructions. Neither of these solutions are a guaranteed fix, but they have resolved the issue in some cases.

As of today, June 1, 2020, the VRS_CMRx and VRS_RTCM32 mountpoints have been configured to include the Galileo and BeiDou satellite data into the correction solution to NC RTN users. CMRx and RTCM 3.2 are the only versions of the output formats the NC RTN has available for the mountpoints that support the Galileo and BeiDou satellite data. The other mountpoints (VRS_CMRp, VRS_RTCM23, VRS_RTCM3) will still include only the GPS and GLONASS satellite data in the solution. Although the VRS_CMRx and VRS_RTCM32 mountpoints are now configured to include the Galileo and BeiDou satellite data, users may not receive any BeiDou satellite correction data because the NC RTN application can’t process the data from the latest BeiDou satellites (BeiDou-3) yet.

The Federal Aviation Administration (FAA) has issued the following notice of GPS interference testing that may result in unreliable or unavailable GPS signal:

FLIGHT ADVISORY: GPS Interference Testing
FORT BRAGG NORTH CAROLINA (FTBRNC) 20-27
23 – 27 March 2020 / Ft. Bragg, NC

This test will be centered at 35.157222°, -79.293333° and extend outward and upward like a bowl affecting the GPS signal 26 NM away at 50 ft above ground elevation (AGL) relative to the center point’s (CP’s) ground elevation (~465 ft MSL), 85 NM away at 4,000 ft AGL, and so on.

The FAA does not provide an affected radius figure of interest to remote pilots for 400 ft AGL. Based on the notice’s data, NCGS estimates this radius to be 46 NM. Since this radius is relative to the CP’s ground elevation, the radius needs to be extended by 5 NM for UAV operations at higher ground elevations where the combined ground elevation difference (remote site elevation – CP elevation) + UAV flight elevation approaches or exceeds 584 ft, 10 NM for 823 ft, 15 NM for 1,127 ft, and 20 NM for 1,506 ft. NCGS recommends adding a wide buffer (>10 NM) to any radius figure for operations near 400 ft AGL.

The NC Geodetic Survey website has undergone some recent back-end changes to enhance security and functionality. If you have not already done so, please update your bookmark for the NCGS page to the URL below.

A collection of short, informative videos about various topics have been made available. The videos can be accessed by clicking the links below:

The NGS HQ building experienced a fire event Friday Sept 9. All servers were shut down and limited user functionality such as CORS data, datasheets and geodetic utilities were switched to the backup systems in Boulder, CO. NGS is working on restoring full service sometime Monday Sept. 12.

A pair of short, informative videos about EDMI baselines are now available. The videos can be accessed by clicking the links below:

The North Carolina Geodetic Survey selected the following private surveying firms for the aerial imagery quality control (QC) project (RFQ #295-01-2016):

• CESI

• Stantec Consulting Services Inc.

• Vaughn & Melton Consulting Engineers, Inc.

The North Carolina Geodetic Survey (NCGS) intends to award multiple Qualifications-Based Selection (QBS) contracts to private surveying firms for the purpose of performing aerial imagery quality control (QC) surveys utilizing Global Navigation Satellite System (GNSS) and traditional survey methods to support the Statewide Digital Orthoimagery Project.

The purpose of the orthoimagery project, which is funded by the North Carolina 911 Board (http://www.nc911.nc.gov/), is to collect seamless aerial imagery for use by local 911 agencies; local, state and federal agencies; and the public.

The work for this Request for Qualifications (RFQ) would consist of performing horizontal and vertical quality control (QC) survey projects.  For more information, please visit the following URL:

https://www.ips.state.nc.us/ips/AGENCY/PDF/11154000.pdf​

Users wishing to download NC spatial data may do so at the following link:

https://rmp.nc.gov/sdd/​

A series of short video tutorials are now available to help navigate the most-recently developed NC Geodetic Database. The videos can be accessed by clicking the link below:

The National Geodetic Survey (NGS) is pleased to announce the Beta release of a new and improved transformation tool in the NGS geodetic toolkit. This redesigned version supports the transformation between geodetic coordinates and State Plane Coordinates (SPC), Universal Transverse Mercator (UTM) coordinates, Cartesian coordinates (XYZ), and U.S. National Grid (USNG) coordinates as a one-stop solution. It features transformation of single or multiple points, Web services, and software downloads. NGS encourages users to try the Beta Version and provide feedback to Krishna.Tadepalli@noaa.gov so the final version may be improved prior to release as on official NGS product.

The update was in the development stage for several months, and it provides surveyors and geodesists with a more efficient and streamlined way of accessing frequently used NGS tools in the geodetic toolkit. The new interface allows one-page easy access to transformations that were previously available only on separate pages.

The Beta version is accessible at: http://beta.ngs.noaa.gov/gtkweb

​From NGS

"When using the geoid models, please be advised that GEOID12B should supersede previous models GEOID12 and GEOID12A. GEOID12B is identical to GEOID12A everywhere, except in Puerto Rico and Virgin island region. For more detail, please read Technical details."

Visit the GEOID12B page at NGS: http://www.ngs.noaa.gov/GEOID/GEOID12B/