New Piper aircraft has hit its mark, it seems, with its first new model since emerging from bankruptcy nearly three years ago. Its Seneca V is a high-flying, fast, efficient aircraft which delivers equally in both aviation benefits and office ac- coutrements. With its blend of near-turboprop speed, high-altitude cruising capability and load-lifting capacity, the Seneca V's $482,500 base price should attract plenty of willing customers. Flight International was invited to flight test the new aircraft.
Although the pre-flight check is as involved as might be expected for a twin-engined aircraft, it is not laborious, and completion is rewarded by a shorter pre-engine-start checklist. Each Teledyne Continental L/TSIO-360-RB, coupled to three-bladed McCauley propellers, fired confidently and settled into a low rumble, idling at about 1,000RPM. The engine run-ups for each side were straightforward, the annunciator-panel tests were out and working and all the pressures and temperatures on the turbine-style dials were in the green.
Ready for take-off
In position for take-off from Vero's runway 29L, I brought up the power levers and the engines spooled up quickly to 2,600RPM, the turbochargers surged to 965mm of pressure in the tuned induction-manifolds, and my heavy right foot nearly ran the Seneca across the runway in my effort to compensate for a stiff right crosswind. All this happened in 5-6s, while the Seneca rushed westbound along the tarmac, on its way to lift off at just over 70kt (130km/h) and accelerating. At 100kt, the vertical-speed indicator (VSI) had long past pegged at the 2,000ft/min (10m/s) limit of its scale.
Trimming to 89kt, the recommended best-rate-of-climb speed, the VSI stayed at the limit, while my view out of the windscreen reinforced a sense that our deck angle was approaching missile-trajectory status. Our time-to-climb calculations, attempted while turning left 160¹, yielded a rate of nearly 3,000ft/min. The Seneca could use a 4,000ft/min, or even a 6,000ft/min VSI, if only to provide greater accuracy.
Once at altitude - only 5,500ft (1,700m) on this occasion - as we streaked in visual-flight-rules conditions above the broken cloudtops towards Bermuda - it was time to bring the power down to something reasonable: 2,400RPM/600mm. After a few minutes to settle in, the aircraft tracked like an arrow at 180kt on a fuel flow of 100litres/h (26USgal/h).
Rolling out of the pattern, we headed out over the Atlantic. The avionics displays glowed in amber and green, while red lights illuminated the digital information centre .
Passengers have the choice of audio or video entertainment, the opportunity to work on the notebook computer, or to chat on the in-flight telephone, while sipping coffee from the executive/entertainment console. It is comfortable, regardless of which seat you are allocated - and that is the idea. "We see the Seneca V as a dual-threat aeroplane," says Chuck Suma, New Piper's president. "By that, we mean that the Seneca V will appeal to the owner/pilot, the entrepreneur who flies himself and, equally to the business executive who never sits up front," he explains.
Although an hour is really too little time to truly wring out a demonstration aircraft, it was enough to sample what the Seneca has to offer beyond blistering speed at jet-like altitudes.
Turbine touches
While sampling different power and speed combinations, scrolling through some of the avionics' offerings and then, reluctantly, preparing to return home, it became apparent that New Piper has wasted none of its two years of secret development to bring the improved Seneca V to market.
With owner-pilots as the first-line target for the Seneca V, it is obvious that New Piper has neglected nothing to give the aircraft maximum utility. That makes it a rather complex aircraft, demanding that pilots learn its dual-redundant systems and master cockpit procedures to extract that utility safely. There are cross-connected vacuum and electrical systems, landing-gear hydraulics and mechanics, electric trim and interconnected autopilot and navigation systems. Interpreting the weather-avoidance information correctly is a matter of learning the system, whether it is AlliedSignal/Bendix King's weather radar or InSight's Strike Finder lightning-detection gear.
The additional equipment and procedural contingencies which accompany the Seneca V's high-altitude capabilities demand understanding of the use and limitations of the supplemental-oxygen life-support system. Also, you cannot ignore mastering the anti-icing equipment available if you want to fly comfortably where few dare. The reward for the work, study and flight time it takes to learn about an aircraft as complex as this is the ability to leap long distances in a hurry, vault weather and depart through known icing conditions to where the air is cold and dry.
At the same time, the Seneca V counters its own complexity with its honest flight traits and sufficient automation to avoid work overload in the cockpit. After all, this is a machine which the lone instrument-rated pilot can command, albeit one which keeps a second pilot in mind with full flight instruments on the right panel.
For me, there is no better place to start than with the benefits of the counter-rotating powerplants common to the entire Seneca line. New Piper has given Seneca pilots an aircraft which tracks straight on the runway and in climb at any safe speed, as well as one which turns with equal ease in either direction, by providing a configuration which pits the torque and power factor of one engine against the other. The greatest benefit may be the lack of a critical engine, the one which, if lost on take-off for instance, demands more from the pilot than if the opposite one failed. The Seneca pilot faces few additional handicaps beyond the immediate needs imposed by an engine failure.
Waste gates
Another aid to the pilot on the L/TSIO-360- RBs is their minimal management demands, because of the automatic waste gates on the AlliedSignal turbocharging system. The gates compensate for changes in altitude, to maintain power setting, no small feat in a fast climber. They also limit manifold pressure to 965mm, where, at 2,600RPM, the engines produce 165kW (220hp) continuously, if you want, all the way to 19,500ft. The book says that you must use full-rich mixture any time you fly using sustained full power, so fuel economy more or less goes out of the window. In single-engine situations, however, you have enough power available to climb at 255ft/min at gross weight.
There is also abundant automation in the avionics stack - including optional autopilot and flight-director systems - and a host of navigation power available through the Bendix/King KLN 90B instrument-flight-rules global-positioning system, another item from AlliedSignal. Although the Seneca V's panel stops just short of going to a full electronic-flight instrument system, its design and equipment raise the bar on piston panels, single or twin. The dual rows of six, 50mm-diameter, turbine-style gauges keep tabs on everything important about the engines and vacuum- and electrical-system performance. Two collections of warning and caution lights are arrayed beneath the brow of the glareshield to alert the pilot of any problems.
There is also one more item which places the Seneca V's panel slightly above even those of many turboprops: the digital information display. Mounted in a box above the engine-gauge stack, this may be configured to show any one of five sets of engine, electrical, fuel and navigation parameters, plus one bonus configuration: power. In the power-monitoring setting, the digital display shows the percentage, within a range of 55% to 85%, of the full 165kW each engine is producing. The power output is displayed to the nearest 5% after the digital brain of the box takes into account engine RPM and manifold pressure, altitude, air temperature and pressure. For better tweaking of power and flight plans, the pilot can use the box to find the engine speed and manifold settings to make a specific power level.
This function allows the pilot to pick a power setting based on a desired fuel flow and set the power according to the box's calculations. Then, to confirm the fuel flows and flight plans, the pilot can dial in a different data setting on the box, and check fuel flow, fuel available - even fuel remaining at the destination. It is as sophisticated a system as found on any turbine aircraft, and far above that available in the piston realm. What is more, it handles well.
A US software company likes to ask in its advertisements: "Where do you want to go today?". The Seneca V begs the same question, albeit more dramatically. It simply begs to be flown - eager and willing to fly; swift and stable once aloft. Returning to Vero Beach gave me the time to sample how the aircraft handles (as if there was really any doubt).
The Seneca shares some of the characteristics of the old Piper's PA- 28 Cherokee, such as the trademark "Hershey bar" wing, full-flying stabiliser on the tail, the comfortably wide fuselage and plenty of dihedral in the wing - 7¹, according to the book. That dihedral, coupled with the engines spinning against one another, delivers a solid stability to the Seneca V's ride, whether trimmed in straight-and-level flight, in a climb or in descent. The dihedral, however, does not resist roll inputs from the differential ailerons, which produced smooth, co-ordinated, turns, with my feet planted firmly on the floor. Better still, the Seneca V held tight to its bank angle hands-off once my pitch trim matched the roll rate - an asset to the instrument pilot. Also, lest we forget, the turns in the Seneca V are equally easy in either direction, one of those benefits from the counter-rotation of the powerplants.
Gear and flap speeds are reasonably high, and the braking action of the three-bladed propellers strong. The gear can go down at 129kt, the flaps at 119kt. With full RPM on the propeller controls and only 560mm of manifold pressure, our curved descent at about 110kt allowed us ample time to slow to 80kt at the middle marker, then to 70kt coming across the threshold of Runway 29L.
This time, my right foot applied only enough rudder to keep the Seneca tracking straight as it crabbed slightly through the last 1.5m of my approach. I dropped the right main, left main, nosewheel; applied a bit less right rudder, brought the aircraft down and braked, just left of the centreline, for the first left taxiway. Pilots will like this aircraft.
Something for the passenger
New Piper sees a second demand in the Seneca V market, so has not neglected the needs of those who might ride in the back, such as the executive who prefers productivity over pilotage. Firstly, the efforts of New Piper's engineers has made the Seneca V the quietest yet, possibly even the quietest aircraft in the New Piper product line. Subjective impressions left me feeling that the Seneca V may be one of the quietest piston aircraft ever built; inside, the cockpit seemed nearly as quiet as that of Cessna's new 172R Skyhawk (Flight International ,January 22-28, P33), but it is not quite the no-headphones-required cockpit which the Skyhawk has today.
Confirmation came from more-objective sources, which measured the Seneca V's outside noise level at about 77dB during fly-over tests; the aircraft even passed Germany's tough noise standards. The smooth engines and three-blade propellers do assist in keeping down bad vibrations; so does new sound insulation.
New Piper's market research revealed that Senecas typically do not need all six seats, but lack working amenities found in more-expensive business aircraft. The company, therefore, decided to give busy executives some utility of their own in the executive/entertainment centre installed just aft of the co-pilot's seat, so that the boss can take advantage of the quiet to work during the flight.
A small, 170mm, liquid-crystal screen can display video tapes played on an optional VCR for the three back-cabin occupants, with the sound piped through the intercom system to their own headsets. Music from onboard audio-tape or compact-disc players can also be piped through, or the passengers can actually work, making or taking calls from a built-in in-flight telephone, sending or receiving facsimiles, or downloading files to a notebook computer powered by a connection in the veneer console. Space also exists to store light refreshments.
With the optional oxygen system come masks and connections for all seats, even if the buyer opts out of the console to take a sixth seat instead. Access to the cabin and aft luggage area is through the wide door on the left aft-fuselage.
New Piper seems to have hit on a new combination for its fifth incarnation of this venerable twin, blending power and fuel efficiency, function and form, comfort and utility. For many busy executives who face the daunting prospect of travelling by airline on multiple 800km legs before returning home, the Seneca V can make three days of travel and meetings fit into one 14h day. Moreover, it matters little whether the boss is up front or in the back, travelling alone or with others.
Putting three people in the back and a pilot up front will not limit the fuel load at a typically equipped weight of about 1,590kg, but it will limit luggage capacity if the pilot's and passengers' weights average the 77kg which the US Federal Aviation Administration deems "typical".
In tune with business
At its maximum take-off weight of 2,156kg, however, the aircraft can carry a full 460litres of useable fuel over distances approaching 1,500km at about 190kt at cruising altitude. If, for example, an early start, say 06.00, is made, the Seneca V traveller can make an appointment 800km away for before 09.00, another in time for a 12.30 lunch, a third in time for a dinner meeting, and be home in time to kiss the children goodnight.
New Piper expects to sell all the Seneca V which it makes - the 38 planned for this year (and even more in the coming years), most of which are equipped up to the $550,000-$560,000 price range. What we must wait to learn is how many owner/pilots bite versus the number of business buyers - and whether riding in the back eventually produces some pilot converts in the process.
Source: Flight International
