Sting S4 RG

The TL-2000 Sting S4 RG is the retractable-gear version of the Sting S4 and the fastest member of the Sting family. It is offered alongside the fixed-gear Sting S4. The RG shares the S4 airframe but adds a fully retractable tricycle undercarriage with braked main wheels and a steerable nosewheel – with all the consequences that brings for performance, baggage and maintenance.

The manufacturer quotes a 9.11 m span and 9.8 m² wing area, and a maximum takeoff weight of 472.5 kg or 600 kg in the LSA version. A dependable empty weight cannot be obtained for the RG: the figure on the manufacturer's website is lower than that of the fixed-gear S4, even though the RG carries the same airframe plus the retraction mechanism – so for payload calculations only the individual aircraft's weighing report counts. Engine options mirror the S4: the 80 hp Rotax 912, the 100 hp Rotax 912 S and the 115 hp turbocharged 914, plus the 100 hp fuel-injected 912 iS as an option. Fuel is carried in a 77 litre fuselage tank plus 44 litres of wing auxiliary tanks.

Performance is predictably higher than the fixed-gear S4. The manufacturer quotes 200 to 250 km/h cruise, a VNE of 305 km/h and a climb rate of 7 m/s at MTOW; maximum level speed is documented at 285 km/h (154 kt), and minimum speed at 65 km/h. Range matches the S4: 840 km on the fuselage tank, 1,370 km with auxiliary tanks, at 16.2 l/h at 75 percent power – in both cases with no wind and no reserve.

The drawbacks are equally clear. Baggage capacity drops to a maximum of 8 kg – the fixed-gear S4 allows 25 kg, and on a touring flight that is a real difference. The retractable gear adds mechanism, maintenance and a failure mode that fixed gear does not have, and it demands more disciplined checklist work. Documentation is also thin: no dedicated flight manual or type certificate data sheet for the RG is publicly available, and the length, height and empty weight figures on the manufacturer's website do not match the S4 airframe. Take-off and landing distances, aspect ratio and glide ratio are not reliably documented for the RG.

The Sting S4 RG is therefore an aircraft for experienced pilots who want maximum cruise speed in the ultralight class and knowingly accept the extra gear maintenance and minimal baggage space. When buying, insist on seeing the aircraft's own manual, its data sheet, the current weighing report and the records for gear maintenance and the emergency extension system in the original. Anyone who needs to carry luggage, or wants a simpler aircraft, is better served by the Sting S4 or the high-wing TL-3000 Sirius.