Nemesis NXT Big Frog

Nemesis NXT F-WNXT Big Frog

The prototype Nemesis NXT, race number 3x (N333XT), flown by Jon Sharp, won the 2008 Reno Air Races Sport Class championship, setting a new race record speed of 631 km/h (392 mph) to 653 km/h (406+ mph) in the  final heat race. The Nemesis NXT won the 2007, 2008 and 2009 Reno Air Races in the Sport Class / Super Sport Class categories.

The French Nemesis NXT Big Frog is  the first carbon-fiber race plane to run on a Diesel. Big Frog  combines the NXT with an SMA SR305-230 engine, which uses less fuel, produces  fewer emissions and has no lead in its go-juice.

Developing nation: USA.
Nemesis Air Racing/Jon Sharp.
Production line: Oro valley Arizona
Type aircraft: Pylon Racer.
First flight: July 10, 2004

When you want to challenge the best air racers in the world, you must innovate. That’s what the Big Frog Team is doing. First, they acquired a competition-proven Nemesis (TM) NXT kit.
Instead of the avgas engine meant for the kit, they decided to use a diesel engine. Fueled by the cheaper Jet A or Jet A1, that engine ensures a longer range and all the reliability of diesel engines.The technical challenge is important: it’s the first time that a diesel engine is to power a composite aircraft and above all to outperform the best racers in the world!

The first pieces arrived in France, raw release in February 2009. The cell is immediately modified by our engineers for the specific needs of the French challenge. Its assembly started at Toussus-le-Noble, goes on the air base 118 of Mont-de-Marsan. 18 months, and some 10,000 hours of work later, on July 11, 2010, the F-Nemesis WNXT alias “Big Frog” flew for the first time. It turns out, in all respects, as expected from the Big Frog Team.

Reno Air Races 2011

For their first participation in Reno this year, the Team established on wednesday a whole set of World Premières :

first diesel-powered racer designed and simulated on computer (with our CATIA and SIMULIA solutions)
– first
diesel-powered aircraft to succed in qualifying at the Reno National Air Races
– first diesel-powered aircraft victory and in his first race!

French Air Force Captain Christophe Delbos. Usually a Mirage 2000 fighter pilot, “Bobos” (his official pilot nickname) made a perfect race. Diving on the first pylon like an eagle, he grabbed the race first position right from the start and kept it during the race six laps! According to him, the aircraft went quite well, allowing him to fully concentrate on clean trajectories until he heard the “Race finished” announcement confirming his victory in his helmet.

The Reno Air Races were cancelled on the second race day Thursday September 16th, when the P51 Mustang “Galloping Host” crashed in the crowd, killing his pilot, James Leeward and killed 11 people and at least 70 people were injured on the ground.

General characteristics

  • Crew: 1
  • Length: 8.30 m
  • Wingspan: 7.60 m
  • Empty weight: 720 kg
  • Fuel capacity: 340 L (74.8 Imp Gallons)
  • Powerplant: 1 × SMA SR305-230 engine
  • Propellers: 3-bladed  constand speed propeller


  • Maximum speed: 653 km/h (406+ mph)
  • Range: 5500 km (840 mi; 3.000 nmi)

All pictures courtesy of Zijde Aviation Photo and Publishing, Rob Vogelaar and Marcel van Leeuwen.