HondaJet's engines went over the wings, and the 'laughable' jet beat its class

In 1997 Honda engineer Michimasa Fujino pitched a light business jet with engines mounted above the wings. 'When I showed people the sketch, everybody laughed at me,' he later recalled — a failed German attempt decades earlier was the cautionary tale, and rear-fuselage mounts were the industry's only answer. In December 1997 he won board approval, and the concept survived Boeing wind-tunnel testing in 1999.

The trick was position. While unpacking after a move, Fujino had come across a 1930s aeronautics textbook by Ludwig Prandtl, whose pre-computer analytic methods he used to locate the exact spot above the wing where the nacelle's shock wave does not add wave drag. In the Boeing wind tunnel the model produced less drag at high speed than conventional clean-wing designs. Freeing the rear fuselage also let the wing use natural laminar flow — rivets and irregularities minimized — and a drag-cutting nose.

The proof-of-concept HondaJet flew on December 3, 2003, and Honda hesitated until it stunned the Oshkosh airshow in 2005. The FAA awarded the type certificate in December 2015 and the first customer delivery followed on December 23. Honda claimed the fastest, highest and most fuel-efficient jet in its class: 483 mph top speed against Cessna Mustang's 391 and Embraer Phenom 100E's 448, a cabin 20% larger than rivals, and roughly 15% better fuel economy.

Mount engines over the wing where wave drag cancels

Rear-fuselage engine pylons cut into cabin volume; moving the engines over the wing freed the entire rear fuselage for seats and a separate baggage bay.

The nacelle was placed where its shock wave stays neutral to the wing's flow, so the 'obviously bad' configuration measured less high-speed drag than a clean wing in the Boeing tunnel.

A natural-laminar-flow wing and a shaped nose compound the drag saving, delivering class-leading speed and fuel burn without a bigger engine.

Honda funded an 18-year program on one engineer's conviction — patience a startup airframer could not have afforded.

A rule everyone learns in school — engines never go on a small wing — can hide a better geometry. Search the parameter space with theory and trust the wind tunnel over folklore.

The HondaJet became the most-delivered very light jet in the world for 2017, 2018 and 2019 — the Triad Business Journal noted the third straight year in February 2020. EASA certified it in May 2016 and Japan in December 2018; the improved Elite arrived in 2018 at about $5.2 million. Fujino, who began sketching the plane in 1997, ran the company as CEO, and the over-the-wing engine mount he proved is now cited in NASA and AIAA over-wing nacelle studies for energy-efficient transport aircraft.