What’s next for the HondaJet?

 - February 1, 2007, 8:45 AM

When it comes to trying to determine what plans Honda has for its HondaJet project, a lot of the seemingly obvious evidence could be misleading. For example, just because the company has spent millions developing the engine and airframe hardly ensures that it actually plans to take it to market anytime soon–if ever.

Aerodynamicist John Roncz (designer of the airfoils on Burt Rutan’s Voyager and other designs) had experience with another project involving a Japanese carmaker. Asked what he thought about Honda’s activity so far, he told AIN, “It sounds Japanese to me.”

Roncz said he was “tangentially involved” in Toyota’s program to develop an aircraft engine derived from the Lexus V8. He said, “The project was an engineering success. The engine worked well. And that was that. You heard nothing more about it.” According to Roncz, the Honda program might fit the same profile. “I wouldn’t be surprised to find that someone at Honda asked what it would take to enter the light jet market, launched the research project and then later asked, ‘Is it a smart thing to do?’”

Another industry observer noted, “What’s the cost to develop the airplane? A few hundred million? For Honda, that’s pocket change.” The same observer conjectured that Honda might have spent the money to develop the HondaJet simply to have a launch customer for its HF118 turbofan.

Jack Olcott, past president of the NBAA and an advisor to the Aircraft Owners and Pilots Association on light jet operations, believes that Honda might ultimately market a jet, but not this one. He agrees with Roncz that the Japanese view tends to be a long one. Olcott told AIN, “Honda could be planning 10 or even 15 years out. It was about 15 years ago that Toyota first looked into the general aviation market. It bought an FBO [AirFlite in Long Beach, Calif.] and did some work on a piston-powered airplane. When a decision [on the fate of the HondaJet] is finally made, it will be made from a solid database.”

Olcott classifies the HondaJet prototype as a Cessna Mustang-size airplane with comparable performance, but perhaps with greater efficiency. He estimates that such an airplane would cost about the same as a Mustang–about $2.5 million.

How Broad a Market?
What would it take for Honda to take the plunge into certifying and building airplanes? Olcott said there would likely have to be a broader market than exists today. One development that might be emboldening the Japanese, he said, is the possible emergence of the air-limo concept stimulated by government-funded improvements to the nation’s aviation infrastructure–along the lines of NASA’s small aircraft transportation system (SATS) initiative.

“My sense,” said Olcott, “is that the Japanese carmaking giants look at aviation as an advanced form of personal transportation. Just as they did in the automotive industry, the Japanese are going to get involved. When? How? Will it be Honda? Toyota? Both? “One thing is sure in my mind: over the next 20 years of development in aviation, Japan will be there.”

A number of business aviation veterans have observed that designing and certifying a crackerjack airplane is only the first step in a successful program. “That’s where the Piaggio Avanti program dropped the ball when it was introduced originally,” said Roncz. The airplane was faster, quieter and far more efficient than a Beech King Air but early on it was plagued by service difficulties. “When you had a $5 million asset parked on the ramp because you couldn’t get a part from Italy, the owner was not going to be happy,” he said.

Regarding the unusual theoretical design aspects of the HondaJet, Roncz took his first look at the airplane on the company Web site while talking on the telephone with AIN. His first reaction? “It’s not a gorgeous airplane, but it’s not horrible looking.” He noted that Rutan designed his Triumph twin with over-the-wing engine pylons, but they were much lower, almost embedded in the wing. “The challenge there was developing an engine inlet shape that would work,” he said. “What we ultimately developed was totally non-symmetric– from top to bottom and side to side. But [engine manufacturer] Sam Williams said the nacelles delivered the cleanest airflow to his engine that he had ever seen.”

Roncz said Honda’s computational fluid dynamics (CFD) research may indeed have arrived at the precise engine/pylon height and angle to deliver optimum lift and airflow without compromising engine inlet airflow. “There might be many configurations that designers have given up on, but that could deliver viable aerodynamic advantages when refined by CFD,” said Roncz.

Regarding the natural laminar airflow on the HondaJet wing, Roncz said that retaining NLF to 45 percent of the wing chord is a conservative configuration, but it makes sense when allowing for possible ice accumulation and other leading-edge contamination. On the subject of the NLF design of the nose section, he said that establishing extensive laminar flow on a three-dimensional body is much harder than on a wing because the airflow is moving out in all directions. His estimate was that the laminar flow section on the nose would extend aft by “a few feet” and deliver about three knots of airspeed, “which they give up again at the vertical/horizontal tail junction. Everything is a tradeoff.”

The MU-2 Lesson
When discussing the HondaJet with its unusual configuration, some observers have harked back to another revolutionary Japanese design, the Mitsubishi MU-2. One said, “To a budding airplane designer in the 1970s, it was everything an exciting, revolutionary airplane should be. It had a tiny wing sprouting a collection of advanced high-lift devices–and lots of power.” The MU-2’s performance numbers did not dictate enduring success, however, leaving the disenchanted to conclude that superior aerodynamics are no guarantee of market longevity.

Whether Honda heeds the lesson of the MU-2 remains to be seen. How it approaches the general aviation market–if it decides to do so after all–will be the measure of success for the HondaJet or its possible progeny. By way of musing, Ken Forester Jr., president of Million Air Teterboro, recalled seeing the first Honda automobiles when he was an Air Force pilot based on Okinawa in the South Pacific in the 1960s. He told AIN, “They were tiny and had chain drives, like Honda’s motorcycles. It took a long time, but look what Honda has done for the automotive industry. If they decide to do it, they could really bring us a wonderful airplane. I’d love to see it happen.”