Private Pilot Magazine|
In the cookie-cutter world of twin-engine planes, the Aerostar stands out from the pack. So thin in appearance, you wonder how tow people can sit abreast inside it. With slender wings mounted mid-way in the fuselage, its appearance alone sets it apart. But the real differentiation lies in its performance.
The disign work for the Aerostar was begun by the Ted Smith Aircraft Company in November 1964, with the first model 600/601 prototype flying in October 1967. Certification was in March 1968 for the 600 and November 1968 for the 601. Additionally, two more certificates were obtained. These were for the use of 180-hp and 200-hp engines, called the Models 360 and 400 respectively. After certification, controlling interest in the company was sold to American Cement. In 1970 American Cement sold the firm to Butler Aviation, but little was done until 1973, when Smith resumed control and started production in Santa Maria, California, on both the normally aspirated 600A and the turbo 601A.
On August 6, 1975, and Aerostar 601A, piloted by Jack Chrysler, set a class C1d, 2000-kilometer, closed-circuit speed record for piston-powered land-planes at 237.08 knots (272.83 mph). Between November 4 and 9, 1977, an Aerostar 601P piloted by Philander Claxton III and Jack Cink recorded a new round-the-world speed record for piston-engine aircraft. The 19,974-n.m. (23,000-s.m.) trip was completed in 104 hours, 5 minutes and 30 seconds, averaging 190.91 knots (219.70 mph).
In 1976 Smith died, and Piper Aircraft soon took over the Aerostar line, eventually moving production to Vero Beach, Florida. On February 14, 1981, Piper announced the Model 602P and named it the Sequoia. This pressurized plane had Avco Lycoming IO-540-AA1A5 low-compression engines with integral turbochargers. The name was later withdrawn.
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The Design Concept
In an address to the Aerostar Owners Association in 1971, Smith detailed the reasoning behind the Aerostar. The following data garnered from the speech's transcript:
Smith had been with Douglas Aircraft and designed the A-20, a low-level attack bomber for the military in World War II. Later he designed the Aero Commander twins for the civilian market. In 1963, when Rockwell decided not to pursue any new development other then the Jet Commander, Smith took six months off to mull over his future. He said that while skiing the slopes of the Lake Tahoe area, he would develop concepts of a new plane and then put them on paper at night. The result was the Aerostar.
Part of Smith's concept was commonality and a reduction in parts. Commonality was achieved by the use of the same parts for the rudder and elevator, and the horizontal and vertical stabilizers. This was a first for the industry. Simplicity and production design were also a major effort. But there was a goal other than just a simpler airplane. Smith wanted the plane to be adaptable to a range of power sources, from a single-engine to "a pure turbine-powered, 500-mph airplane." His idea was to put as much of the heavy and beefy equipment on the outside to use it for structural strength. One such way was the elimination of many pieces of under-structure and substitution of heavier-gauge skins (0.050 inches, twice the normal wing-skin thickness). This made the skin carry more of the bending, torsion and shear loads. Smith said there are 50 percent fewer model-specific parts in the Aerostar than in competitive types.
These understructure alternations and heavier skins gave the plane a rigid structure that directly relates to a high dynamic factor. Smith said that as such, the plane, as it's built, can be flown at true airspeeds of 800 mph without getting into the flutter parameters. He aslo said the plane has been flown at altitude, with power and in a slight decent, at 500 mph true. Statically, the plane was tested to 6000 pounds gross and an ultimate load factor of 6 Gs with no deformations, no permanent sets, no cracks and no failures of any kind. Additionally, the load was held for an indefinite period of time at this ultimate load factor. The FAA requires a hold of five seconds, but "...since nothing was happening, we just kept the load on for an indefinite period of time, then relieved the load, and the airplane came back to its normal status as it was before the loat was first applied." He also said that strain tests showed the plane could double its gross weight with nothing more than minimal structural changes.
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The Question of Stability
Before we get too far along, let's address the issue of the plane's reputation. As with all planes and people, there will be stories about the good and bad points. When I mentioned to some friends that we were going to do this story, I was regaled with stories about the plane falling out of the sky. Asking Jim Christy, Aerostar's vice president, about this, he said the story originated with stall tests. A test pilot took the plane and ran a series of stalls, involving 90 percent power and the plane in a dirty configuration. At about 64 knots, which is way below Vmc, the plane's wing was flying, but the rudder lost effectiveness. The next things to go were the ailerons, but the wing wwas still flying - just the oppostie of what's desireable.
The solutions are many and varied, plus too long and technical for this article. Over the years, Machen Inc., a company that still specializes in Aerostar modifications and is closely allied with today's Aerostar Corporation, used a number of devices - not to make the wing stall, but to ensure the control surfaces work at these low speeds. On the back end, one problem was that the rudder's leading edge protruded into the airstream when rotated, causing a burble and airflow seperation at low speeds. Smoothing the air and keeping it in contact with the rudder required the installation of vortex generators, fairings added to the rudder hinge points and small airfoil surfaces added at the fin's base to prevent the air from flowing up the stabilizer. Piper, while working on the same situation, added another rudder on the bottom of the plane, but this didn't seem to be quire as effective. (Vortex generators are small airfoils, about 1/2 X 1 inch, that are attached to the fin/wing and angled to the fin's/wing's chord. As the air passes over and around, the airfoils induce high kinetic energy, which decreases the boundary layer and reduces the speed at which there's airflow separation.)
Up front, the ailerons are a Frise design, in which a small portion of the surface sticks down into the airflow when the aileron is rotated up. When rotated down, the surface between the wing and the aileron is smooth. This is designed to counteract adverse yaw. At slow speed and maximum deflection, the aileron on one side of the plane would stall. Therefore, vortex generators have been installed on the bottom of the wing.
Subsequent testing has shown that the plane can be controlled, completely stalled with full flaps and 90 percent power, within 15 degrees of roll and yaw, at 52 knots, while descending at 4000 fpm.
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The Model 700
Through the 1970s, Piper continued to modify and improve the Aerostar line and announced the addition of the PA-60-700P, called the Aerostar 700P, to the line on November 20, 1982. Design on the 700P, by Piper, had started in January 1981, with prototype construction initiated six months later. The first flight was in September 1981, and production began in December 1982. FAR Part 23 Amendment 6 certification was received in May 1983, and the first customer delivery was in December 1983. The model was also certified for flight into known icing. Only 25 of these planes were built.
Prior to that, however, in 1980 Machen started producing an upgraded version of the Aerostar 601P. Called the Superstar II, or Super 700, its engines were replaced by TIO-540 engines with Garrett TA-18 turbochargers and induction air intercoolers, each rated at 350 horsepower and driving a Hartzell three-blade propeller. Robyn Astaire's plane, N40X, was a Piper-built 602P that was transformed into a Super 700 Aerostar by Aerostar Aircraft/Machen Inc.
The Piper version, if indeed there was nay difference at all, of the Model 700 sported a pair of intercooled, flat-six, counterrotating, 350-hp Lycomings, TIO-540-U2A engines. The plane's cruise speed increased to a reported 261 knots (mid-cruise weight and optimal altitude), with enough capacity in the turbo system to maintain power and cabin pressure to 25,000 feet. The single-engine ceiling is 16,500 feet, which will get you over all the dirt here in the lower 48.
But the powerplants are only part of the picture, as we were to discover upon examining Astair's 700P. Shining in the sunlight, the plane's paint scheme is tastefully designed. In fact, Astaire is so proud of the design, she said there's a design patent on the color and scheme. While the fuselage's breadth appears to be small, the interior is surprisingly commodious. Entry to all the seats is through a clamshell-type door located at the pilot's seat. With the pilot's seat all the way forward, entry is easily accomplished. Putting the only door at the pilot's elbow takes the term "a pilot's plane" to a new level, especially in an emergency. Lest anyone think this callous, there's an emergency exit above the wing on the starboard side.
Astaire's plane is as luxurious as one could imagine, with leather, carpeting and a tastefully done decor. Her seating arrangement is a pilot, copilot (not required) and up to four passenger seats with a center aisle. Once inside and ensconced in the copilot's seat, I found all the instruments easily within view - and there were quite a few items to see. The almost entirely King avionics assembly includes a pair of KY196 coms, two KNS 81 RNAV receivers, a KLN 88 loran, a Trimble 2000 GPS (used for IFR approaches), a KN 64 ADF, all of which are fedding into a color King EFIS centrally mounted in front of the pilot seat. To round things out, there's a cluster of JPI engine instruments on the right sidewall. We bemoaned the fact that we weren't able to view all this at night, because Astaire said the colors on the panel are outstanding.
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The Aerostar has a few items that aren't standard to most other aircraft. The fuel system has electrically operated fuel valves because, we're told, Smith didn't want to run the fuel lines all the way into the cockpit. I doubt if this was a safety factor, because fuel is stored in the aft end of the fuselage. The entire fuel system consists of intergral wing tanks that, when combined with the standard fuselage bladder, provide a capacity of 173.5 gallons, of which 165.5 are usable. Astaire's aircraft had another tank, located behind the main fuselage tank, holding 40 gallons. Prior to our photo flight, which is accessed on the left side of the fuselage just aft of the wing.
Ground steering is accomplished by using a toggle switch to control electrical power to a small hydraulic selector that, in turn, supplies hydraulic pressure to a nose-steering cylinder to turn the nosewheel. the takeoff run is kept straight by using the brakes and rudder exclusively.
As with most twins, once aligned on the runway, the engines are brought up to a nominal power setting, in this case about 30 inches, before the brakes are released. The rest of the power required, considering the runway, weight, temperature, etc., is then applied. In a number of planes I've flown, even this approach isn't sufficient to prevent a rudder dance to keep the nose centered, what with the engines coming up to power at their own rate. Astaire's Aerostar tracked straight with little rudder input.
About 90 knots (Vr is 89 KIAS) the nose is brought up, and with all that power, the plane flies off and starts an incredible climb of well over 1500 fpm at Vy (117 KIAS). Unfortunately, we had to level off almost immediately, though it seemed that the plane wanted to go up to its optimum cruising altitude, which would be in the low 20,000s. Forming up with the Cessna 210 photo plane, flown by Dave Stevenson, we reduced our speed to 120 KIAS. This speed left lots of power to accelerate yet was still high enough above the 82 KIAS stall speed to be very comfortable. The plane handles like a sports car, with immediate response in all directions. The airspeed brakes located on the bottom of the wing in the root area allow quick descents with less concern about engine cooling and can be used for formation flights such as ours. Astaire said she flies IFR almost exclusively, so this was a great thrill.
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Thinking of Buying?
When you spend the six-digit figures required to buy a plane like this, there's a lot to know. First, are you ready for the plane? Training is available at many of the better flight training centers across the country. You should opt for one with a simulator, but, unfortunately, none of the centers have an Aerostar-specific simulator. Simulator flying has to be the most tedious thing in the world, but it's the only place you can safely practice system failures and in-flight emergencies. The Aerostar should be transitioned to - just like any high-performance aircraft - with care, caution and excellent training. Just because your buddy has a few hundred hours in an Aerostar doesn't mean he can - or should - check you out. Along with the flight training centers, there are a number of highly qualified individuals available. A complete list of these people is available from the Aerostar Owners Association.
As with any airplane, having a pre-purchase inspection is mandatory. And, like the training, this should be done at a facility where the mechanics are familiar with the plane. There are a few specific areas and problems to look for that only experience can provide. We called Bill Bridges of The Flight Shop, a full-service FBO, which was one of the original service centers for Ted Smith in 1969 and is now located in Brigham City, Utah. (Call 435/723-3469 or visit www.theflightshop.com.) Bridges is still in businesss, and his company specializes in Aerostar maintenance, overhauls and modifications. In a far-ranging conversation, he said the most important thing in any Aerostar is compliance with all the ADs and Service Bulletins. A close inspection of the plane should include, especially on the 1969 and 1970 models, a detailed examination for skin corrosion. During these two years, the planes were manufactured with untreated Alclad aluminum. Subsequently, the skins were anodized and/or coated with zinc chromate.
Bridges said a few areas where they've noticed cracking is in the main-wheel and nosewheel assemblies, but these are easily repaired with a doubler. There's also a restricted fitting on the vent side of the fuel pump that should be checked. As a hint for those of you looking for a plane, Bridges said he thought the 1979, 1980 and 1981 models are the best. These were the years the planes were built at Santa Maria, just before Piper moved the process to Vero Beach, and the expertise of the manufacturing personnel was at its best.
As mentioned, the logs should be thoroughly gone through to be sure all applicable ADs, Service Bulletins and routine maintenance have been complied with. A list of each can be obtained from Aerostar. One of the best things about buying an Aerostar, unlike most out-of-production planes, is that all the "wear" items are still manufactured in the factory in Idaho.
As for a test flight, Christy said the plane should meet all the original specs. It's also important to climb to its service ceiling of 25,000 feet, which is the only way to test the integrity of the turbos and pressurization system. With a detailed inspection and a high-altitude test flight, you should be sure the plane will take you high and fast for a long time.
The Aerostar Owners Association, located in Valdosta, Georgia, can be reached at 912/244-7827. It's an excellent source of information about training and service centers in your area.
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The Robyn Astaire Story
From Horses to Horsepower
by Judy Whitson
Speed and horsepower have historically conjured up an image of the male half of our species. This isn't always true, and, in fact, the love of competition is gender neutral. Robyn Smith Astaire remembers having a love of horses, a fascination with airplanes and a desire to go fast since the age of two. At 22 she mounted a horse for the first time, and two years later she was a professional jockey. At not quite 5 feet 7 inches, she was tall for the sport, but her slim figure kept her within the weight limits. Her drive, talent, single-mindedness and work ethic helped overcome the prejudices against female rider that abounded in the paddocks.
In August 1972 she appeared on the cover of Sports Illustrated as the first successful woman jockey. Her career lasted 10 years. During her rise to fame and fortune, she was introduced to Fred Astaire at the Santa Anita Racetrack. Fred loved racehorses almost as much as dancing, and he may have harbored a secret desire to be a jockey. It wasn't until five years later that they became better acquainted over dinner. They married in 1980 and had seven years together until Fred died of pneumonia in 1987.
Devastated and lacking a goal to occupy her mind and time, Robyn acted on a suggestion from a friend and enrolled in a career guidance course at UCLA. After completing the course, the testing showed that she had a aptitude for flying helicopters. In 1990 she earned her private pilot rating in a helicopter at Van Nuys Airport in California. She subsequently purchased a Robinson R22. That sparked the desire to fly other types of aircraft, and over the next few years, she earned the following licenses and ratings: ATP, multi-engine land; rotorcraft-helicopter; BH-206, CE-600, DC-3, LR-Jet; commercial privileges, airplane single-engine land and sea; and airplane, multi-engine sea. Most of her ratings were obtained at FlightSafety International, but her ATP was completed in a DC-3 at Santa Monica Airport in California.
Besides the elegant Aerostar, which Robyn purchased in 1995 form Dick Taylor, the vice president of Boeing Aircraft, show owns a beautiful Glasair. She has enjoyed this sporty little plane very much, but with a packed schedule, there's little time to keep two planes exercised. After eight years, she has reluctantly put the Glasaire on the market.
Robyn has flown commercially in Learjets and Citation Ultras for Northwest Jet and other companies. She's looking forward to continuing her career in aviation, piloting elit corporate jets such as Challengers and Gulfstream IVs. She prefers a plane you can stand up in and, of course, can go fast in. Robyn has a great desire to fly a P51. There's always Reno.
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