Contact: Dan Ohlson – 213.536.7041

Chicago, IL  – Ken Dufour, ASA and Jason Zilberbrand, NAAA, long-time veterans of the General Aviation industry, announced today that they have taken over the management and day to day operations of VREF Publishing.

Founded in 1993, VREF is the industry’s most trusted and recognized valuation guide for fixed wing aircraft and helicopter assets. 

“As we enter into this new chapter of our careers, Jason and I are committed to leveraging our decades of experience in order to meet the needs of owner/operators, brokers, financial institutions and aviation professionals,” said Dufour, the company’s CEO.

“We will provide exceptional service, share our passion and expertise–and take an active personal interest in the success of each client,” he added.

Dufour is harnessing a 50-year career in aviation to grow Vref into the largest Appraisal company in aviation. Dufour has spent twenty years as a board member for Embry-Riddle, as well as the Chairman of the Embry-Riddle Student Life Committee. Dufour is considered the foremost expert  in appraisals, expert witness and diminution of value claims. 

Zilberbrand grew up in aviation and spent his early twenties building JSSI with his father into the largest independent provider of power by the hour. He is highly respected in the international aviation community and has established himself as an expert in aircraft appraisals and valuations of aviation assets.

Throughout their careers, Dufour and Zilberbrand have demonstrated their commitment to excellence by:

  • Being relationship-focused, not just transaction-focused
  • Treating each client with honesty and transparency
  • Conducting their work with passion and innovation 

“The private aviation audience has been in need of a modernized valuation guide for some time. With our expertise, and background Vref will be upgraded to offer new features, and numerous new categories of aviation assets. ” said Zilberbrand, the company’s president 

“We look forward to providing aviation professionals with trusted, verified and empirical data that helps them conduct their jobs easier, smarter and faster,” concluded Zilberbrand.

For more information about VREF, go to


About ASA

The American Society of Appraisers (ASA) is an international valuation association that teaches, tests, accredits and refers professional appraisers. ASA is the oldest and only major organization in the United States representing all disciplines of appraisal specialists, originating in 1936 and incorporating in I 9 52. Visit ASA ‘ s Web site at or call (800) 272-8258 to locate ASA -accredited appraisers.

About Embry-Riddle Aeronautical University

The American Society of Appraisers  (ASA) has a working educational relationship with Embry -Riddle Aeronautical University, the world’s largest, fully accredited university specializing in aviation and aerospace. Embry-Riddle educates more than 28,000 students annually through the master level at residential campuses in Daytona Beach, Fla., and Prescott, Ariz.; Through the extended campus at more than 130 teaching centers in the United States and Europe; and worldwide through distance learning.

About NAAA

The National Aircraft Appraisers Association (NAAA) is the Trade Association for professional aircraft appraisers. Since 1980 the NAAA has been the Certification entity and has established the standards and Code of Ethics for professional aircraft appraisers in the United States and abroad