This the second in a series of Legacy Pilot Reports featuring aircraft from the Plane & Pilot archives that sport enduring, timeless features and have a classic appeal.
It's more than coincidence that several manufacturers seem to hit upon the same good idea at the same time. Though we may like to think otherwise, general aviation is a relatively small industry, and everyone seems to know what everyone else is doing. Hard experience has taught that he who waits often gets left behind.
So it was in the late '70s when Piper, Cessna, Mooney and Commander all decided to upgrade their normally-aspirated, entry-level retractables to turbocharging. Prior to that time, exhaust-driven induction air compressors, though hardly new, had generally been confined to larger engines.
For its part, Piper wasn't exactly without experience with turbos. The Lock Haven company had been offering turbocharging on the Comanche, Twin Comanche, Aztec and Navajo for as long as a decade. But extending turbocharging to the bottom of the line proved to be more of a challenge than Piper anticipated.
The problem was that Lycoming wasn't eager to pump compressed power through the little four-cylinder mill that powered the Arrow. At 200 hp, the IO-360 fitted to the early Senecas and second-generation Arrows had proven durable and reliable, and Lycoming wanted to retain that reputation for long, trouble-free life. There was an aftermarket retrofit turbocharging system available that utilized a second throttle, but Piper wanted a simpler built-in arrangement.
The powerplant Piper finally settled on for the turbocharged Arrow was another 360-cubic-inch engine, only this time the cubes were distributed between six cylinders. Cessna had been using Continental's TSIO-360 in pairs on the huff-'n-puff model 337 Skymaster for 10 years (though with decidedly mixed results on the rear, pusher position), and the engine seemed to offer just what the Vero Beach Company was looking for. Piper had introduced the engine on its turbocharged 1975 model Seneca IIs, and accordingly, the first Turbo-Arrows used the F versions of the same powerplant.
The Turbo Arrow III premiered in 1977 with the semi-tapered Warrior wing and a blower under the bonnet. Sales were good, over 400 units the first year, but engine problems surfaced almost immediately. Engines in early Seneca IIs and Turbo Arrows were about as reliable as Mir, plagued with overheating problems, turbo, valve and case deficiencies and initially saddled with a short, 1,400- hour TBO. Later Arrows and Senecas were upgraded to the -FB series engines, and that solved many of the problems, upgrading TBO to 1,800 hours.
Despite early teething problems, the Turbo Arrow developed into a decent seller and was to last some 13 years on the marketplace. The PA-28R-201T turned out to be an ideal airplane for some pilots, especially those operating consistently from high density altitudes or flying in areas plagued with low-level weather. A short step up from Piper's Archer or Dakota, the new model was a foot in the door to turbocharging. Max operating altitude was a conservative 20,000 feet, and critical altitude, the height above which the engine could no longer deliver full rated power, was a low 12,000 feet.
Still, the T-Arrow was a truly simple machine. It offered the docile handling of its normally-aspirated namesake, including a stall that was practically non-existent, automatic gear extension (a feature that was to be deleted several years later) and perhaps the most uncomplicated systems of any retractable of the time. Piper sold some 1,700 of the type during its 13-year production run.
Dr. Bill Grider of Kokomo, Ind., found the debugged Turbo Arrow's combination of talents exactly to his liking. Though he makes a living working on teeth and there's no question he loves his job, his heart truly is in the sky.
A 20-year pilot, Grider bought his first airplane, a normally-aspirated Arrow, in 1986, then stepped up to turbocharging in 1993. "The big attraction of Arrows for me has always been their extremely docile nature," says Grider. "Like their fixed-gear counterparts, they're very easy-flying airplanes. The old automatic gear made them almost foolproof for pilots transitioning to retractables, and it's a shame liability concerns caused that system to be disconnected."
On the surface, Grider's 1977 Piper Turbo Arrow looks nice, but not exceptional. The paint is essentially stock, though it's still in good shape, and the interior is decent but not outstanding. Only the panel is inwardly impressive, complete with a Garmin 530/430 package, Stormscope, EDM-800 engine analyzer, backup instruments and at least one of everything else that can be crammed into the available space (even a panel-mounted Iridium satellite phone).
What's most interesting about Grider's T-Arrow, however, is the total package. The airplane is meticulously clean, scrupulously maintained, beautifully equipped and conservatively flown, a combination that has preserved a prime example of the type.
Dentists aren't always known for being adventurers, but Bill Grider is cut from a slightly different mold. He'd been planning a North Atlantic crossing for several years and finally set the summer of 2002 for the trip. Unlike many people in his income bracket, Grider doesn't suffer from arrogance, perhaps the most stereotypical disease of the wealthy. In addition to exhaustive preflight planning and comprehensive survival equipment, Grider wanted the security of flying with someone who knew a little about the ocean. He apparently assumed I knew as little as anyone, so he contracted me to accompany him on his trip.
The plan was that he'd make the outbound flight, hop off in France after he'd seen the elephant, and I'd return the airplane to Indiana. Grider even went to the trouble (and plenty of it, following the 9/11 terrorist attacks) of having his airplane FAA-approved for an additional 50-gallon ferry tank in the fuselage, apparently on the premise that the only time you can have too much fuel over the ocean is if you're on fire. In combination with 72 usable gallons in the wings and slightly reduced cruise power settings, that gave us over 10 hours of endurance, a good hedge against the unexpected.
Launching in mid-June, we flew the usual milk-run route through Greenland and Iceland, eventually winding up at Tousous le Noble Airport outside Versailles, France, practically within sight of the Eiffel Tower. After a day off in Versailles, I departed Tousous, flew to Wick, Scotland, and retraced our steps across the Atlantic to Indianapolis while Bill Grider toured France.
For that reason, I spent 30 hours in the right seat watching Grider fly and another 30 hours at the controls of his airplane on the return trip, unusual exposure for a pilot report.
Speed was never the primary goal on the PA-28R-201T. Coaxed to the high teens, the airplane probably will turn in the 167 knots Piper promises, but it's unlikely many pilots would operate the airplane so high. The T-Arrow isn't really happy in the flight levels. It seems to do its best work at non-oxygen altitudes, 10,500 to 12,500 feet. At that height, Grider says he flight plans for 150 knots and gets it or slightly more most of the time.
The good news is that turbocharging preserves decent climb at indecent altitudes. At mid-cruise weight, the Turbo-Arrow is capable of nearly 1,000 fpm to 10,000 feet, then can generate 700 to 800 fpm ascent through 15,000 feet. For most pilots of turbocharged airplanes, invigorated climb at medium altitude is far more valuable than improved cruise up high. Few airplanes come to grief because they're too slow, but lack of climb performance can be a very real safety concern.
Piper's original concept had been to offer a retractable Cherokee 180, and after the original model was upgraded to 200 hp, the Turbo-Arrow only added a blower and two additional cylinders to that formula (along with the modified Warrior wing). The primary goal was to improve the model's takeoff and climb performance at medium heights. The normally-aspirated Arrow was a popular airplane on the East Coast and throughout the Midwest, but it had limited applications in the Mountain West.
The RayJay turbocharger fitted to the Turbo-Arrow was a simple device, basically a modified diesel truck turbo. The system utilized a manual waste gate, so it was up to the pilot to regulate manifold pressure within reasonable limits. That limit was generally 41 inches of manifold pressure. If a pilot pushed too hard on takeoff below a 12,000-foot density altitude, a tiny amber light would illuminate at top panel to warn of an overboost. For pilots who still didn't get the message, a pop-off pressure relief valve would automatically open at about 42 inches to vent compressed air and prevent engine damage.
Trouble was, the amount of throttle necessary to generate 41 inches seemed to change with practically every takeoff, contingent upon temperature, pressure, humidity, the pilot's IQ and the phase of the moon. The throttle often manifested a stubborn, cumulative nature—push a little and nothing happened, push a little more and still nothing, push even harder and power would suddenly come pulsing in with a rush, often overshooting what you were aiming for.
The same problem could make setting power for cruise a frustrating experience, especially in rough air. It seemed the manifold pressure often had a mind of its own. Any change in mixture or rpm could cause mp excursions, and any modification of pitch that varied the supply of ram air also generated turbo bootstrapping.
Most of the time, things didn't become that dramatic. With a little practice, you could learn to anticipate the onset of boost during takeoff, and experience could overcome frustration in setting power for cruise. After 10 years of flying the airplane, Grider is hardly aware of the turbo, and the system even became moderately friendly to me after the first ten hours. If an aviation writer can do it, anyone can.
The cabin is a modestly friendly place to visit, though at 41 inches across, it won't accommodate folks who are broad of beam. In all honesty, two people in survival suits with a ferry tank in back practically require synchronized breathing. Under more normal circumstances, the airplane is adequate for two men with copious luggage on short trips, or two couples with reduced fuel and no bags on a Sunday flight.
The Turbo Arrow's manners at the opposite end of the envelope have always been stereotypically Cherokee. Stall is so tame that some instructors criticize the derivative, fixed-gear Warrior for being too docile. Pre-stall buffet is adequate, but the airplane refuses to do more than the characteristic Cherokee hobby-horse bucking at the break. Such gentle handling makes landings super simple. Should you drop one in from a few feet, the T-Arrow's air-oil oleos absorb the impact and let you down easily.
Like any owner who's lived with his airplane for a decade and uses it for more than short weekend trips to the outlying airport restaurants, Grider is pleased with his choice, and he intends to utilize it to the maximum. He's planning to take the airplane on a two-week tour of Alaska this summer, possibly a flying vacation to South America in summer 2004, and who knows where he'll wind up the following year.
Whatever the destination, Grider can relax and enjoy the ride in what is probably the simplest turbocharged airplane in the sky.
According: planeandpilotmag.com
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