National Technical Systems, a Calabasas-based engineering and...

National Technical Systems, a Calabasas-based engineering and environmental testing concern, said it promoted several executives and that two new directors joined its board.

Arthur Edelstein, formerly executive vice president and chief engineer and one of NTS’s founders, was named chief operating officer. Lloyd Blonder, formerly vice president for finance, became a senior vice president. Skip Brown, who was vice president for marketing, also was named a senior vice president. Lloyd Carlson, formerly program manager, was elected chief engineer.

Robert I. Lin was named secretary to succeed James J. Slaby, who resigned. Lin is the son of Jack Lin, NTS’s president and chief executive.

NTS’s stockholders also elected Richard D. Short and William L. Traw to the company’s board. Short and Traw are vice presidents who manage NTS’s Fullerton and Saugus divisions, respectively. They replaced Leslie H. Blum and Stanley Schoen, who resigned.