Aircraft overview

The Tomark Aero Viper SD-4 is a Slovak, two-seat, all-metal light sport aircraft built by Tomark Aero. The design first flew in the mid-2000s, with customer aircraft appearing in the late 2000s, and it has been offered in European ultralight and light sport categories as well as in export markets. It is a low-wing, tricycle-gear aircraft intended for private flying, flight training and efficient cross-country use. For buyers, its importance lies in combining conventional metal construction, straightforward Rotax power and side-by-side seating in a compact LSA-class airframe.

Performance & specifications

Typical Tomark Aero Viper SD-4 performance depends on national certification basis, propeller choice and installed equipment, but most aircraft are built around the 100 hp Rotax 912 ULS four-cylinder engine, with some later examples using modern Rotax variants. Typical cruise speeds are in the region of 105 to 115 knots. Practical range is commonly quoted around 500 to 600 nautical miles, subject to fuel capacity, reserves and operating weight. In the 1,320 lb light sport configuration, useful load is usually in the mid-500 lb range, sometimes approaching about 600 lb on lighter-equipped aircraft. Published service ceiling figures are generally around 15,000 feet.

Cabin & avionics

The cabin seats two occupants side by side under a clear canopy, with dual controls and a panel layout suited to training or private touring. Baggage capacity is modest, as expected in this category, so weight and balance should be reviewed carefully when comparing individual aircraft. Avionics vary widely. Earlier aircraft may have traditional analogue engine and flight instruments, while upgraded examples often feature glass panels such as Dynon SkyView, Garmin G3X or similar light aircraft EFIS installations, plus VHF radio, transponder, GPS and engine monitoring. Garmin Perspective and G1000 suites are not typical installations for the Tomark Aero Viper SD-4.

Buying & value

Used-market evaluation should focus on airframe condition, documentation, engine hours, propeller logs, compliance with Rotax service requirements and the aircraft’s exact certification status in the buyer’s country. Check landing gear attachments, canopy condition, fuel system records, avionics installation quality and any ballistic recovery parachute fitment or repack status. Common value drivers include low engine time, modern EFIS avionics, clean maintenance history, desirable paint and interior condition, and evidence of factory or approved maintenance support. In the used market, the Tomark Aero Viper SD-4 typically sits as a practical metal LSA alternative to composite sport aircraft, appealing to buyers who prefer conventional construction and economical Rotax operation.