In attempting to understand the Piaggio P.180 Avanti II, you need to begin by forgetting everything you thought you knew about turboprop-powered airplanes. The idea behind the Avanti has always been remarkably simple and completely outside the turboprop box. Think of the Avanti II as a jet with props and you’ll be close to the mark, though in many respects, it’s not an easy mental shift to make. Turboprops behave in certain ways, and jets in other ways, but the Avanti II is a true hybrid, a product that blends the best traits from two very different airplane categories to arrive at some third niche, which at present it occupies by itself.
In the process it doesn’t hurt one bit that the Avanti II just so happens to be one of the sleekest and most beautiful airplanes ever built. It just so happens to be one of the most unusual looking ones too.
From the beginning, Piaggio Aero intended the Avanti to be a turboprop that played in the same niche as light jets but with better economy and a larger cabin. It pulled the concept off. The Avanti II does indeed have a big cabin, the best in its class by far, and it also has good speed and range, and best-in-class fuel efficiency. Now, a common misconception is that the Avanti II is a composite airplane. It is not, at least not primarily. The fuselage, wings, tail and forward wing of the airplane are metal, though admittedly metal that has been shaped and smoothed in a way that makes a compound curve look like child’s play. Other parts, mainly fairings and the like, are composite, but for the most part, Piaggio Aero’s Avanti II is a sheet metal airplane.
The use of alloys instead of composites was a purposeful choice for Piaggio Aero, which certified the airplane more than 20 years ago at a time when there were few successful composite models and sheet metal seemed to augur a shorter approval program than plastics did. It wasn’t the only fast turboprop twin with a forward wing — the Beech Starship was a contemporary, though that company stopped production of the composite cabin-class twin shortly after it started it, admitting later that the composite model was so time-intensive to build that it was simply unprofitable. Piaggio Aero, on the other hand, is still steadily producing its model. It has delivered nearly 200.
The Shape of Fast
If materials were a conservative approach, configuration was not. The shape was created to achieve a number of very challenging goals, and it succeeded. The shape, you’ll see, is not simply for show, though ironically it shows very nicely.
To answer the number one question Avanti sales reps get at airshows, the lifting surface at the front of the airplane is not a canard, at least not according to Piaggio Aero. It is, instead, a forward wing. The difference between the two, they say, is that the forward wing, while a lifting surface, is not a controllable one. There is no “elevator” in it; hence, it’s not a canard. I’ll let Peter Garrison work out both the semantics and aerodynamics of the question (if those two disciplines would differ on the subject). I call it a three-surface design, with forward wing, main wing and tail.
Unlike what I think of as a canard, in the Avanti the elevator is back on the tail and the ailerons are on the trailing edge of the wing, along with some very serious flaps, which are designed to deploy slowly so as not to cause a dramatic pitch change — they succeed at that, by the way. The main wing of the airplane is very small (172.2 square feet, slightly less than a Cessna 210’s) and very highly loaded.