Development and manufacture of the Viper SD4 and Skyper GT9 Ultralight (UL) / Light Sport Aircraft (LSA) planes, is done in TOMARK s.r.o., TomarkAero and TomarkAero CZ Division, by experienced specialists in aviation and mechanical engineering. The latest technologies and CAD systems, as well as CNC machining, are used in their manufacturing.
We offer you exclusive photos from the production and finishing, unique photos from strength tests of the plane’s structure under various loads. The uniqueness of Viper SD4 is also in the fact that it is one of the few planes in its category that have successfully passed the elasticity tests of all its parts, the so-called Flutter tests. Viper SD4 successfully mastered the SPIN tests, which are necessary for obtaining a certificate EASA CS-LSA. Viper SD4 RTC has been certified according to EASA certification specifications CS-LSA Amdt.1. EASA.A.606
Our primary intention is to offer you, our partners, customers, and aviation enthusiasts, specialised information, quality consulting and exclusive documentation. If you like the things you learn, photos and videos, or if they inspire you or encourage you to propose a change or modification, please let us know. We look forward to your views and ideas.
Viper SD4 
Skyper GT9 
