Corporate Profile

Executive Team

  • Robert W. Haulbrook Jr.
 President & CEO


    Robert W. Haulbrook Jr.


    President & CEO


    Robert Haulbrook is President and Chief Executive Officer of GTA. Haulbrook has 30 years of experience in communications market segments including wireless, landline phone service, long distance, and digital television services both nationally and internationally. 
He has worked in more than 10 international markets in Asia, Australia, South America, Central America, the Caribbean, Europe, and in the Middle East.

His previous positions include founder and CEO of Cellular Center, a wireless phone retailer based in Alabama. 
He also served as chairman and CEO of Meteor Mobile Communications in Dublin, Ireland, as well as general manager of Centennial Wireless in San Juan, Puerto Rico. 
Earlier in his career, Haulbrook held various executive level positions in telecom marketing, sales, product development and strategic planning.

Haulbrook holds a bachelor's degree in Marketing from Georgia Southern University.

  • Andrew M. Gayle, Jr.
 Chief Operating Officer


    Andrew M. Gayle, Jr.


    Chief Operating Officer


    Andrew Gayle has 18 years of experience in the telecommunications and information technology field in Guam, including stints at GUAMCELL Communications, ComputerLand of Guam, and Pacific Data Systems. Andrew joined GTA in 2005 and was tasked with building, launching, and operating the GSM network, which debuted in January of 2006.

Gayle graduated from Harvard University with a bachelor’s degree in Computer, Electrical, and Systems Engineering.

  • John Brady
 Chief Financial Officer


    John Brady


    Chief Financial Officer


    John Brady joined GTA as Chief Financial Officer in 2007. Brady has had extensive experience in the telecommunications field. Prior to joining GTA, Brady held the position of Chief Financial Officer at Orbcomm, a global satellite communications and asset tracking company based in New Jersey.

He also worked as CFO of Magyar Telekom in Budapest, Hungary, a $2.5 billion in revenue local exchange carrier listed on the New York Stock Exchange. He was also Deputy CFO of the Danish telecommunications provider, Teledanmark, based in Copenhagen, Denmark.

Brady graduated with honors from the University of Pennsylvania with a Bachelor of Science in Metallurgical Engineering and received a Master of Business Administration in Finance/ Accounting from the University of Michigan, also graduating with honors.

  • David R. Chase
 Chief Technical Officer


    David R. Chase


    Chief Technical Officer


    David Chase joined GTA in 2007. He brings over 22 years of experience in the telecommunications industry, 
with a deep technical background in product definition, development, applications, and 
deployment with emphasis in telecommunications, wireless systems, control systems, and signal processing fields.

Prior to his employment with GTA, Chase held the position of President and CEO of Vareda Engineering, Inc., 
based in California, as well as prior positions at Agile Materials and Technologies, Inc., and Superconductor Technologies, Inc. also in California.

Chase graduated from the University of California, Santa Barbara, with a Master's of Science, specializing in Electrical Engineering.

  • Roland Certeza
 Executive Vice President of Sales & Marketing


    Roland Certeza


    Executive Vice President of Sales & Marketing


    Roland Certeza joined GTA upon privatization in 2005 as Sales Director for Business Markets and has since been promoted to Executive Vice President to oversee all sales and marketing activities related to consumer, government, corporate, and wholesale market segments. He was instrumental in launching new lines of business and opening 5 new retail outlets over a 6 year period. This includes successfully negotiating a 5-year strategic contract with the Navy and Air Force to expand retail presence within the bases.

Prior to this, Certeza was a Senior Sales Manager at MCI Worldcom, a Systems Consultant at Deloitte and worked as a Senior Account Executive and Business Analyst at Sprint International. Certeza holds a Bachelor of Science Degree in Business Administration Accounting from San Diego State University and a Masters of Business Administration Degree from the University of Guam.

  • Steve Redman
 Executive Vice President of Operations and Customer Service


    Steve Redman


    Executive Vice President of Operations and Customer Service


    Steven Redman joined GTA in 2009. His departments at GTA include inside and outside plant operations, network operations including TV, wireless and internet, as well as business and residential client services. He was first on Guam in 1992 for the shore landing survey work for the Micronesian Inter-Island Cable System.

    Redman spent 10 years in business networking and internet services preceded by 10 years in submarine cable installation and operations. Steve has a Bachelor of Science Degree in Mathematics from University of Washington and a Master of Science in Science and Technology Management from Oregon Health & Science University.

  • Daniel J. Tydingco
 Executive Vice President of Legal, Regulatory and External Affairs


    Daniel J. Tydingco


    Executive Vice President of Legal, Regulatory and External Affairs


    Before joining GTA, Dan Tydingco was director of policy, planning and community relations for the Unified Courts of Guam. Previously, he served as executive officer of the Supreme Court of Guam.

    Tydingco began his public service career in 1983 as a congressional aide in the U.S. House of Representative for then Guam Congressman A. B. Won Pat. He later served as the deputy press secretary for the late Governor Ricardo J. Bordallo and as chief of staff for the legislative committees on Water, Utilities and Telecommunications as well as Judiciary and Criminal Justice.

Tydingco holds a bachelor's degree in Political Science from Regis University in Denver, Colorado. He is a member of the boards of directors of various professional, civic and service organizations including recent service as Chairman of the Port Authority of Guam Board of Directors.

  • Sharon Davis
 Vice President of Service


    Sharon Davis


    Vice President of Service


    Sharon Davis has been with GTA since 2006. Her team of over 70 service professionals includes Call Center, DSL and Digital Television Technical Assistance, the wireless handset "Genius" Bar and iPhone support, field services dispatch and scheduling, Lean-Six-Sigma analysis and process improvement, along with the 24/7 critical infrastructure Network Operations Center (NOC).

Prior to working at GTA, she was the Advertising Manager at the Pacific Daily News. She has a Bachelor of Arts in Communications from University of Nebraska at Omaha.

  • David Duenas
 Vice President of Network Operations


    David Duenas


    Vice President of Network Operations


    David Duenas joined GTA in 1994 working as an engineer under the Guam Telephone Authority. As an Inside Plant Engineer, he worked on the wireless network before transitioning to Operations in 1999 to oversee the implementation and operation of Guam's first DSL network. As Plant Manager in 2003, Duenas was responsible for the daily operations of the telecommunications infrastructure. Since 2005, Duenas has worked on the implementation of the DWDM optical network and GTA IP TV services.

Duenas is a graduate of Seattle University with a Bachelors of Science in Electrical Engineering and is a member of the Institute of Electrical and Electronics Engineers. Prior to joining GTA, he worked for Puget Sound Power & Light and General Electric ED&C.

  • Andrew C. LaBrunda
 Vice President of Information Technology


    Andrew C. LaBrunda


    Vice President of Information Technology


    Andy LaBrunda joined GTA in 2005 as a programmer in Information Technology.

Prior to joining GTA, LaBrunda worked as a Senior Technologist for CSC Contractor, Command Naval Forces Marianas being responsible for intranet application development, data warehousing, and developing a BaseComm inventory system.

  • Carl Leon Guerrero
 Vice President of Operations


    Carl Leon Guerrero


    Vice President of Operations


    Carl Leon Guerrero brings more than 12 years of telecommunication experience to GTA. As Vice President of Operations, his role is to establish direction and budget the operations and Capital Expense Project Plan for GTA. He is also responsible for the day-to-day installation and repair teams, as well as all construction projects for the network on island.

    Leon Guerrero has had close involvement with the installation of GTA's SONET OC192 core network with OC48 sub-tending rings and designed the on-island redundant network for one of GTA's key Federal customers.

As a Chief Engineer with former government run Guam Telephone Authority, he has had many highlights in his career, such as the implementation to convert Guam to Feature Group D Equal Access and the inclusion into the North American Numbering Plan.

  • Duncan Cope Leuenberger
 Vice President, Corporate Security


    Duncan Cope Leuenberger


    Vice President, Corporate Security


    Duncan Cope Leuenberger, Sr. joined GTA in 2011 as the Vice President of Network Security and Business Development and Enterprise Services. He has 26 years of enlisted and commissioned Joint and Air Force Communications experience. Leuenberger is also appointed as the Federal Security Officer responsible for GTA's National Security Agreement and is implementing a company-wide security program.

Prior to joining GTA, Leuenberger was the Deputy Squadron Commander and Operations Flight Commander for the 36th Communications Squadron at Andersen Air Force Base, Guam. He holds a Bachelor's of Science Degree in Management of Information Systems from Bellevue University in Nebraska, along with an Associate of Applied Science Degrees in Computer Programming and Information Systems Operations from the Community College of the Air Force.

  • Rose Ayuyu Morales, PHR
 Vice President of Human Resources


    Rose Ayuyu Morales, PHR


    Vice President of Human Resources


    Rose Morales joins GTA with an extensive background in Human Resources, most recently employed at Comcast Cable in California since 2007. Prior to joining the GTA team, she worked as a Regional Human Resources Business Partner/Leader and moved throughout Northern, California working in the Fresno, San Jose, Concord, and Sacramento areas. While working with Comcast Cable, Morales was responsible for over 300 employees and partnered with all levels of leadership to align business objectives with human resources. She has over 14 years of experience in HR.

Her educational background includes a Bachelor's Degree in Business Administration with an emphasis in Human Resources Management from Golden Gate University, received in 2000. Additionally, she received her professional certification (PHR) from the Society of Human Resources Management in 2000 as well, and completed the Labor Relations certification from the Human Resources Policy Association of Labor Relations.

  • Yudhishter Parmar
 Vice President – Business Planning and Process Control


    Yudhishter Parmar


    Vice President – Business Planning and Process Control


    Yudhishter Parmar joined GTA in 2006 as a Managing Director of Finance. Prior to his work at GTA, Parmar worked as the Construction Project Manager at DFS Guam LLP. He has also held a position as financial consultant with Deloitte and Touche LLP.

Parmar holds a Bachelor of Science in Computer Science from the College of William and Mary. He continued his education at Tulane University, earning a Master of Business Administration in Corporate Finance and International Management.

  • Joseph Shinohara
 Vice President of Finance and Controller


    Joseph Shinohara


    Vice President of Finance and Controller


    Prior to joining GTA, Shinohara was with Ernst & Young LLP, with industry audit experience in telecommunication, construction, hospitality, retail, wholesale, non-profit, and government agencies.

A Certified Public Accountant and Chartered Global Management Accountant, Shinohara graduated Summa Cum Laude with a Bachelor of Business Administration (double major) in Accounting & Management from the University of Guam. Additionally, he is a member of the American Institute of Certified Public Accountants and Guam Society of Certified Public Accountants.

  • Leo Taitano Yanger
 Vice President of Wireless Engineering


    Leo Taitano Yanger


    Vice President of Wireless Engineering


    Leo Taitano Yanger joined GTA as Vice President of Wireless Engineering with over 20 years of experience in programs, projects, operations and personnel management, coupled with 15 years of RF design, optimization and performance engineering management of CDMA, EVDO and LTE wireless services.

Prior to joining GTA, Yanger worked as the RF Manager/Director for MetroPCS in Las Vegas, Nevada and Senior RF Engineer for MetroPCS in Sacramento, California. During his tenure in Las Vegas, he was instrumental in managing the wireless network with the highest visibility in the United States and managing the design, implementation and performance of the first commercially launched LTE network in the U.S. From 1994 through 2000, Yanger also managed the installation, operations and maintenance of the first PCS CDMA Wireless network on Guam.

As a Captain and Communications Officer in the U.S. Army from 1985 to 1993, Yanger managed U.S. Army telecommunications units in the Republic of Korea, Hawaii, and the in the Persian Gulf during Operation Desert Storm. He holds a Bachelor's Degree in Communications from the University of Hawaii.