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.
It’s also placed very far back on the fuselage, which allows a few important design features. First, with a far aft wing the engines — two Pratt & Whitney PT6s in a pusher configuration — can be mounted very far aft as well, which helps keep the interior noise low. Occupants can converse easily, as can the pilots. The problem with the aft mounting is that the Avanti II has a very distinct exterior noise signature that is problematic — while by all accounts the Avanti II is no noisier than other PT6-powered twins.
While the forward wing is not fitted with an elevator, it does have a flap, or set of flaps, depending on how you look at it. The surface, which like the tail has a considerable amount of anhedral, is ice-protected, as is the windshield, by electric heat. Bleed air would have been nice, but by the time it had traveled the distance from the engines, it’s not clear that it would have been very hot anymore, and the bleed air used to heat the wing leading edges robs the turboprops of a great deal of power to begin with. Along with the wings, the engine inlets and wing leading edge are deiced by bleed air; the tail does without, as do the props, which are heated directly by the engine exhaust blowing over them.
Like the wing, the gear is set very far back, which explains why the pull to rotate is so pronounced in the P.180. Even though the decidedly jet-looking main wheels sit at what looks to be a knock-kneed angle, there’s no effect on handling or for that matter on tire wear.
The other huge advantage of the configuration is that it opens up the fuselage, allowing a cabin that is closer to that of midsize jets than light jets. For private owners, charter customers and fractional owners, the big cabin is a major selling point. The cabin, interestingly, isn’t symmetrical; it’s a little cozier up front than in back. But with a main cabin height of 69 inches, it’s easy to move about. It’s also remarkably wide for an airplane of its size. At 73 inches across, the width allows for great shoulder room, easy entry though the airstair door and a very comfy hard-door lavatory.
In the end, the Avanti II’s configuration allows it to achieve light jet speeds in the same way as light jets do, by using a very small, highly loaded wing to go with a good dose of power. The Avanti takes that formula and pushes it to the design edge, achieving that performance with a great deal less power than in comparable jet products and with the best cabin in the class by a long shot. It’s a great formula.
Technology and Comfort
The airplane has been constantly improved over the past decade, with new interiors, higher max takeoff weight, higher Vmo and avionics upgrades galore. Today’s airplane has the Rockwell Collins Pro Line 21 avionics suite, with all the bells and whistles. With fully reversionary flat-screen displays with a host of safety utilities, including TCAS, TAWS, satellite weather and more, the avionics suite is top-notch, and Piaggio Aero has been working with Rockwell Collins since the introduction of the Avanti II to add upgrades as they became available. One that’s lacking is the single FMS. A fully independent backup navigator can be installed as an option. Some operators use a Garmin 430 mounted on the far left side of the panel.
The Avanti II, I should probably mention, is a single-pilot airplane; it doesn’t need a crew. Theoretically, a newly minted multiengine pilot with a high-altitude endorsement could hop right in and go flying. In reality, the P.180 is a fast, sophisticated, high-flying airplane that requires the same kinds of skills and training as any single-pilot business jet. Most charter operators fly the Avanti II with a crew of two.
Flying the Avanti II
I flew a new Avanti II out of Denton, Texas, home of Avanti completions in North America, with Piaggio America’s Grant Spigener. Grant has been flying the Avanti for years with thousands of hours of experience in the airplane, much of it under typical charterlike conditions. He was a good guide to have for my first flight in the airplane.
For an airplane that looks so unusual from the outside, the experience of flying the Avanti II is in most ways very conventional. The biggest problem I had was in remembering that I wasn’t flying a jet and that mounted 30 feet in back of me, completely out of sight, were two turboprop engines. As a result, the engine management chores on the P.180 are more complicated than those in today’s fadec-equipped light jets. The start-up sequence is pure PT6; it’s a completely pilot-controlled process. Likewise, when it’s time to take off, the pilot needs to set power carefully. It’s a hard transition for a pilot coming back to PT6s after having flown modern fadec turbofans from Williams and, yes, from Pratt & Whitney.
Taxiing feels conventional, though it’s accomplished using an electrically actuated, hydraulically powered nosewheel steering system. In ground idle and with power pulled back to idle, the airplane still has a tendency, like many turboprops, to get going too fast, so you need to use beta to keep things slowed down. Though the very basic levers don’t look as though they have reverse capability, they do, though it requires a healthy lift on the levers to get them back over the gate to provide propeller braking to slow things down on the ramp and taxiways.
Once on the runway and cleared for takeoff, we checked to make sure the flaps were set for takeoff and the steering was too — there are different modes depending on how fast you’re traveling though there’s no tiller — and that our trims and condition lever were correctly set. Acceleration feels fast, but steering through the rudders is positive and smooth, though it requires an easy touch to avoid darting about. We rotated at 105 knots, which is pretty darned fast for a turboprop, using about half of the available 7,000 feet at KDTO. I asked Grant to put the gear up on positive rate of climb, and soon thereafter I called for the flaps to be retracted. I stayed on the flight director as we climbed, quickly getting into IMC and getting rapid-fire climb-and-maintain clearances along the way. Grant handled the radio tuning.
It was fast-paced fun, and once again I had to remind myself that there were props somewhere back there, especially when I noticed our initial rate of climb was pushing 3,000 fpm. At FL 250 it was still better than 2,000 fpm at 170 knots indicated.
I was pleasantly surprised at how nicely the Avanti II handles. Despite the fact that it took me a while to get a feel for the trim button — there’s a little activate button in the center of the trim hat — the hand-flying was nothing short of delightful. I kept on the controls through a number of heading changes much up into the midteens before switching on the autopilot.
While the rate of climb is great, one thing the Avanti II doesn’t do is climb or descend at very high indicated airspeeds, the former a condition of available thrust. So as fast as it is at cruise, its block times suffer as a result of the climb speed and relatively low Vmo (260 indicated) and Mmo (Mach 0.70) limitations.
Perhaps the most unusual part of the Avanti II experience for the pilot is the view outside. As it wraps itself around the pointy nose of the P.180, the windshield stretches out for several feet in front of the pilots and wraps back around them tightly. The effect is a view that changes substantially as you point the nose up or down in various phases of flight. A traffic target can be out of view in certain positions, at around 2 o’clock for the left-seater or 11 o’clock for the right-seater. On climb-out, especially given the steep angle of attack of the impressive-climbing P.180, it’s hard to see much out front at all. On approach, however, the view is excellent.
The plan for my flight was to climb to 30,000 up to the Wichita VOR to do something I’d never done before, an RVSM check. I won’t get into the details of it here, but suffice it to say Grant was busy with taking notes as I flew the airplane. Once having completed that check, we asked for and got a climb to FL 380, a common long-range cruising altitude for the P.180, which has a ceiling of 41,000 feet. I could see why 380 is a preferred altitude. At that level we were seeing 380 knots or Mach 0.664 on 600 pounds of jet-A per hour, not per side but total. That’s slightly less than 100 gallons per hour, a figure light jets simply can’t touch.
After we’d checked figures at 380, we headed down briefly to FL 320 on the way back to Dallas. Once level, we were rewarded with what was nearly the top speed of the P.180, which was consistently 395 knots bumping up to that magical 400-knot figure on a couple of occasions, those figures at around 800 pounds per hour total. We were light and it was slightly colder than standard, both of which help boost true airspeed numbers by at least a few knots. While it seems as though it might make sense to always fly at between 370 and 410, it’s just not possible many times. This is another advantage of a turboprop. The fuel penalty for flying in the 20s is not as extreme as it is in turbofan airplanes.
The Avanti II gets its best range figures, up around 1,500 nm, at higher altitudes and lower fuel burns, and Grant told me that the range is real, commenting that he has never had to make more than one fuel stop going from any one point in the continental United States to another. This kind of range makes the P.180 a great bet as a regional airplane or one that’s based in the Midwest. Of course, with higher operating weights you won’t be able to carry as much fuel or, hence, get as much range, though the truth is that most flights in a 400-knot airplane are less than 1,000 nm anyway, and with a thousand-mile range as the target, you can liberally load the P.180.
This, along with the airplane’s great cabin and operating economies, has made the Avanti II the airplane that has helped create the remarkable success of charter and fractional operator Avantair, which operates 57 Avantis. In fact, Avantair late last year took possession of the 100th Avanti delivered in the United States, which has been far and away the model’s best market.
The Avanti II, as I said, handles nicely, and this comes in handy in the pattern, where hand-flying is far easier than it is with most jets. The Avanti feels very stable and is easy to maintain altitude in while hand-flying compared with other airplanes in and around its class.
Landing the P.180, as I’d heard previously, is interesting in that the attitude is very flat. Considering the shape of the nose in front of you, this is handy, because the runway stays in easy view the entire time. The approach speeds are very fast by turboprop standards. You fly final at around 120 knots; when you pull back on the power as you land, the nose rises slightly, the mains touch, and you relax back pressure and prepare to get stopped, a job that is greatly aided by big carbon brakes and extremely effective prop braking. At sea level under standard conditions, the Avanti II needs almost exactly the same amount of runway to land as it does to take off, just over 3,200 feet.
When Flying first flew the Avanti in 1990, we predicted that its great fuel efficiency would be a big selling point, and that has been true. What we didn’t fully realize is that over the next 20 years no light jet would emerge that could challenge the P.180’s remarkable combination of speed, fuel efficiency and cabin size, a trifecta of strengths that has made it a popular transportation airplane with operators for whom efficiency, comfort and high style are the hallmarks of having arrived.