Yamaha-Powered STOL Highlander

Devil Girl namesake Sherri Sanches and pilot/builder Eddie Sanches.

Eddie Sanches herds an American Airlines 777 around for a living, but on the weekends he enjoys the rough and tumble world of STOL drag racing. Three years ago he purchased and raced a Just Aircraft Highlander with a Rotax 914 engine, which he later upgraded to an EP 912, putting out 155 hp. At ArkanSTOL 2022 (what a great name for a STOL event) Eddie ran into seasoned STOL racer Kevin Hoopes, who was working on a one-off Highlander XL designed with modifications to make it a top tier competitor. Sadly (or not so sadly in Eddie’s perspective) Kevin then became a partner and designer at Badlands Aircraft to work on their new Vaquero model. Kevin had to devote his time, attention and loyalty to the new brand, so he and Eddie struck a deal where they would both finish the new Highlander and Eddie would walk away with the keys at the end of the process. Eddie and Kevin finished STOL Race 48 only a month before Reno.

Skytrax gear box and 4 blade NP prop.

What resulted was the creation of a next level Highlander with an incredible new powerplant and stunning build quality. The engine on this creature comes from the world of Yamaha snowmobiles (“snow machines” if you are from Alaska). Officially the engine is designated the Sidewinder 998T, and yes, the T stands for turbo. This little 3 cylinder engine currently puts out about 250-260 horsepower, but Eddie is expecting tweaks to bump up that number to over 300 hp. The engine spins at 8200 rpm static and 9300 in anger. All that torque is converted to thrust with a Skytrax fully reared gear box built by Teal Jenkins and a four blade NR prop.

Yamaha 998T engine, bumping up on 390 HP.
Go fast engine management switch. “nasty girl” setting is for racing.

The most impressive feature of Race 48 is its incomparable build quality. If it had been completed on time for AirVenture, it would have certainly won the dead grass award (and probably a Lindy). Eddie named his ship “Devil Girl”, his nickname for his wife and crew chief, Sherri Sanches. The cockpit features a sleek Dynon SkyView installation, overhead switches and grand champion level fit and finish. This ship is not only beautiful, it is all built for STOL racing. Eddie designed and fabricated a motorcycle style twist grip throttle on the flap handle which enhances the speed in which he can change configurations and power settings. The landing gear was designed and built by Acme Aero.

SkyView panel with twist grip throttle on the central flap handle.

The final STOL Drag results were determined on Saturday night. Eddie and Devil Girl Race 48 scored an incredible second place finish among the squadron of seasoned and well sorted out competitors. Eddie says that he is not through tweaking and modifying Devil Girl. He will be competing at ArkanSTOL later this season.

Race 48 with Lexan panels to enhance visibility in race conditions.
Cockpit with SkyView panel.

This article originally appeared in KITPLANES. For more great content like this, subscribe to KITPLANES!

Steve Ashby
Steve Ashby is a sometime lawyer and full-time aviation aficionado from Atlanta, Georgia. He learned to fly in 1980 and has adopted a 1968 Skyhawk (your Grandma could fly it). Steve is also working on a Van's RV-8A which he swears will be completed on (a) Thursday.


    • Since Yamaha makes engines that are designed to live best above 8k rpm,, it should live as long as any motorcycle engine. Personally I think I would rather have a brand new less expensive engine with half the TBO than dropping $40K on a field rebuild on a Lycosaurus core.

    • These high turning small motorcycle engines are near bullet proof. My last bike had a 600cc inline four in it. It redlined at 15K. At about 8K it felt like an afterburner ignited. HP comes with those high rpms. When I sold it, I had 28K miles on it. Never burned a drop and the valve inspection , not necessarily adjustment, wasn’t recommended until 25K miles. That’s a lot of rpms. Mine checked just fine. The are amazing engines. Reliable gearboxes are making them practical for other other uses.

  1. Can agree, a pal bought a CBR 600 c 1990, rode the hell out of it for over 30000 miles, not sure if he ever changed the oil let alone ever serviced it and it was still running strong when he unloaded it.

    The Yamaha and gearbox/prop combo seem like a great idea, hope we see more like it!