One designer, one basic recipe — a slender wing and a small engine that can be stopped in the air — worked through half a dozen generations.
René Fournier was a French aeronautical engineer with a simple, stubborn idea: a light aircraft that flew like a sailplane whenever its engine wasn't running. Every type in the family that follows is a variation on that idea — low-winged, wooden, aerodynamically clean enough to soar cross-country on a stopped propeller, and light enough to be flown from grass strips by amateur pilots.
Almost none of it was built at any scale by modern standards. Total production across the whole family runs into the low hundreds, spread across several manufacturers in France and Germany as licences and companies changed hands. That's part of why the surviving airframes — including the handful still flying in the UK — matter enough to keep track of individually.
Fournier's first design, the RF1, flew in July 1960: a single-seat, high-set-wing motor glider powered by a converted Volkswagen car engine. The refined RF2 followed in 1962, backed by French government funding, and only two were ever built — but it proved the concept enough to justify a production version.
Fournier partnered with Alpavia to put the RF3 into series production. It first flew in March 1963 and roughly ninety were built before production ended in 1966 — a low-winged, single-seat wood-and-fabric motor glider capable of soaring for hours with the engine shut down, and surprisingly at home in gentle aerobatics.
A reinforced, fully aerobatic development of the RF3. Alpavia built the first few as the RF4; production then passed to Sportavia-Pützer in Germany, whose version — the RF4D, "D" for Deutschland — became the most numerous Fournier of all, with well over 150 built. An RF4D crossed the Atlantic in 1969, and the type is still the one most UK owners mean when they say "a Fournier".
A tandem two-seat development of the RF4, first flown in January 1968 and built in the same wood-and-fabric tradition, with a retractable centre wheel and wingtips that fold for hangar storage. The later RF5B "Sperber" fitted a longer wing and a Limbach engine. Around 200 RF5-family aircraft were built before production ended in 1975, and it's the type most commonly still found sharing UK syndicates today.
While Sportavia awaited German state funding for the RF6, aerobatic pilots kept asking for a shorter-span, more powerful single-seater. Fournier's design office put around 1,800 hours into cropping the RF4D's wing and fitting a bigger Limbach engine, and the RF7 flew for the first time on 26 February 1970 — a complete technical success by every account. Certification was refused anyway, because its Volkswagen-derived engine lacked the dual ignition system the standards of the day required. Only the prototype and two amateur-built examples were ever completed.
A three-seat, tricycle-gear design that moved away from the classic Fournier formula toward a more conventional light touring aircraft, aimed more at flying schools than at soaring pilots.
A return to two-seat motorgliding, but with the crew seated side by side rather than tandem, and foldable wings. Only 14 were built: the wooden airframe was heavier than contemporary glassfibre rivals, and the engine struggled for take-off power and range. Financial trouble at Fournier's company followed, and the design was eventually sold on without further production.
A ground-up response to the RF9's shortcomings, introducing plastic and carbon-fibre structure in place of wood. Licence production in Brazil, as the Aeromot AMT-100 Ximango, gave the design its longest production run and widest distribution — including military use by the Portuguese Air Force — long after the original French company had wound down.
A note on scope. This timeline now covers the RF7 as well as the mainline story; it still skips the one-off RF8 to keep the arc readable. RF8 gets its own page in the Aircraft section, alongside every other type from RF1 to RF10. If you spot something worth adding here, the contact page is the way to reach us.
