David B. Zilkoski

About David B. Zilkoski

rss feed

David B. Zilkoski has worked in the fields of geodesy and surveying for more than 40 years. He was employed by National Geodetic Survey (NGS) from 1974 to 2009. He served as NGS director from October 2005 to January 2009. During his career with NGS, he conducted applied GPS research to evaluate and develop guidelines for using new technology to generate geospatial products. Based on instrument testing, he developed and verified new specifications and procedures to estimate classically derived, as well as GPS-derived, orthometric heights.

Now retired from government service, as a consultant he provides technical guidance on GNSS surveys; computes crustal movement rates using GPS and leveling data; and leads training sessions on guidelines for estimating GPS-derived heights, procedures for performing leveling network adjustments, the use of ArcGIS for analyses of adjustment data and results, and the proper procedures to follow when estimating crustal movement rates using geodetic leveling data. Contact him at dzilkoski@gpsworld.com.

Posts by David B. Zilkoski

A look at NGS’ experimental and hybrid geoid models Posted on 05 Dec 2018 in the Opinions & Survey categories.

On Aug. 10, the National Geodetic Survey (NGS) released its latest experimental geoid model, xGeoid18. In early 2019, NGS is scheduled to release its next hybrid geoid model, Geoid18. NGS’... Read more»

NGS 2018 GPS on BMs program in support of NAPGD2022 — Part 9 Posted on 03 Oct 2018 in the Opinions & Survey categories.

The number of GPS on Bench Mark (BM) stations highlighted as complete on the National Geodetic Survey (NGS) GPS tracking page as of Sept. 25 represents 43 percent of the... Read more»

NGS 2018 GPS on BMs program in support of NAPGD2022 — Part 8 Posted on 01 Aug 2018 in the Opinions & Survey categories.

My last two columns (NGS 2018 GPS on BMs program in support of NAPGD2022 — Part 6 and NGS 2018 GPS on BMs program in support of NAPGD2022 — Part... Read more»

NGS 2018 GPS on BMs program in support of NAPGD2022 — Part 7 Posted on 06 Jun 2018 in the Opinions & Survey categories.

My last column described the National Geodetic Survey’s (NGS) GPS on Bench Marks (BM) 2018 interactive web map, and provided an update and status report on stations observed in support... Read more»

NGS 2018 GPS on BMs program in support of NAPGD2022 — Part 6 Posted on 04 Apr 2018 in the Opinions & Survey categories.

The NGS is offering a great opportunity to provide data that will help to improve the hybrid geoid model in your region. Read more»

NGS 2018 GPS on BMs program in support of NAPGD2022 — Part 5 Posted on 07 Feb 2018 in the Opinions & Survey categories.

My last column highlighted two components of the North American-Pacific Vertical Datum of 2022 (NAPGD2022) — the geoid undulation model of GEOID2022 and gravity model of GRAV2022. It expressed that these... Read more»

Discussing the new North American-Pacific Geopotential Datum of 2022 — Part 4 Posted on 06 Dec 2017 in the Opinions & Survey categories.

My last column focused on the National Geodetic Survey’s (NGS) current plans for estimating North American-Pacific Geopotential Datum of 2022 (NAPGD2022) GNSS-derived orthometric heights and incorporating geodetic leveling data into... Read more»

Discussing the new North American-Pacific Geopotential Datum of 2022 — Part 3 Posted on 04 Oct 2017 in the Opinions & Survey categories.

My last e-newsletter column discussed the basic foundation parameters of the North American-Pacific Geopotential Datum of 2022 (NAPGD2022); that is, a global geopotential model, the GRAV-D project, and the GEOID2022... Read more»