Socata TB-10

Without a doubt, its one of the most stylish singles flying; think of it as a French Archer. But it hasnt been a big seller in the U.S. and sales efforts have waxed and waned over the years.

SOCATA TB-10 Tobago

Thomas Borchert

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It may not be fast, or carry a lot and although it hasnt been a stellar seller in the U.S., say this about the SOCATA TB-10 Tobago: Its a good looking airplane, perhaps one of the best looking ever built. Thanks to sleek lines, a racy looking set of gull-wing doors and a nicely proportioned afterbody, the TB-10 just looks right.

When it was introduced to the U.S. in the mid-1980s, the SOCATA Caribbean series was nothing if not a bold aesthetic statement. These French imports the Tampico, Tobago and Trinidad brought much-needed spark the flagging U.S. industry. Unfortunately, the timing was awful and the French just never figured out how to sell airplanes the way Cessna has. The current FAA registry shows only about 70 TB-10s in the U.S. and nearly three times as many TB-20.

Why consider one? What the Caribbean series brought to GA was a fresh look at the design of light aircraft. They use the same engines as others and perform about the same. But theres considerable innovation here: a high degree of parts interchangeability, superior ergonomics and simple, efficient construction. Whereas the typical Cessna or Piper isnt all that different from what preceded it, the SOCATA airplanes certainly are modern airframes.

The entire series has a sleek, exotic look both inside and out. Reportedly, SOCATA farmed out the TB series interior to an industrial designer with a lot of experience laying out the cockpits of high-performance automobiles. Most pilots agree that he earned his fee. Good human engineering combines with maintainability in an excellent, integrated interior design.

SOCATA

The Tobago is made by SOCATA, an acronym for the Societ de Construction dAvions de Tourisme et dAffaires, literally, a company for building business and pleasure aircraft. Its a subsidiary of the largely French-government-owned aerospace conglomerate Aerospatiale.

SOCATA is the successor to Morane-Saulnier, the original developer of the Rallye or MS 880 and Potez, which took over the Morane-Saulnier facilities when the former went bankrupt. These all ended up as part of Sud Aviation, one of several nationalized aerospace companies, which became part of Aerospatiale in 1970.

In 1998, SOCATA began work on a new generation of aircraft to replace the Caribbean series. The MS series (Morane Saulnier again) has essentially the same airframes, but was supposed to be the launch pad for SMAs innovative aerodiesel engine, developed in concert with Renault. Although SMA continues to peck away at the diesel project, the powerplant has yet to find a home in an OEM aircraft. SOCATA felt the engine wasnt quite ready for commercial launch.

The Caribbean series consists of three basic airplanes, the TB-9 Tampico, for the low-and-slow trainer market; the TB-10 Tobago (aimed at the Archer and its ilk) and the retractable TB-20 Trinidad. There are several submodels, such as the TB-21TC turbocharged retractable and the 200-HP Tobago XL. All look similar, because the airframes are virtually identical.

The TBs which designates Tarbes-built, the location of SOCATAs factory appeared at the Paris Air Show way back in 1977 and the TB-10 was the first

SOCATA'S TB-10 Cockpit

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of the series certified, in 1979. After a TB-10 was taken on a market survey tour in Canada and the U.S. in the fall of 1980, several plans were made and abandoned. In 1984, a distributor was appointed to import and market the line, starting with the retractable TB-20 Trinidad. This arrangement flopped in short order.

Finally, the company took control of its destiny in 1986, establishing a U.S. subsidiary based in Grand Prairie, Texas, alongside Aerospatiales well-established and ongoing helicopter operations. That operation has since re-

SOCATA'S TB-10 Doors

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located to North Perry Airport, Florida and can be reached at 954-893-1400.

SOCATAs original timing couldnt have been worse. In the mid-1980s, most American GA manufacturers were admitting defeat and shutting down their production lines. Cessna bailed at about this time, but SOCATA found enough dealers to make the venture fly. With typical French quirkiness, the production flow was off kilter at first. The American components of the airframe, such as the engine, were built here and shipped to France. Each airplane was assembled there, test-flown, disassembled, shipped to the U.S. and reassembled here. Starting with the TB-9 Tampico in 1992, a production facility opened in the U.S.

Airframe

The Caribbean line proved to be no copycat of American designs. More like cars than traditional airplanes, the designs were driven by efficient manufacturing and minimized parts counts. A parallel objective was to simplify maintenance and reduce operating and life-cycle costs.

As a result, theres near-total airframe commonality across the series. Except for minor differences in such elements as wing dihedral and trim surfaces, the structure and aerodynamic surfaces are common to the entire series. The fuselage is built up from several large sections: a metal semi-monocoque tub forms the lower half of the cabin section up to the door sills; the top half of the cabin structure is fabricated from aluminum sheet, with distinctive gull-wing doors and large windows; the tail cone is a semi-monocoque structure.

The wings are almost constant-section, with some variation in leading-edge shape and twist at the outer sections for aerodynamic control at the stall. Chord is narrow. Relative to wing span (32.5 feet), the ailerons appear stubby. Most of the trailing edge is taken up by the single-slotted flaps. The spar is milled as opposed to being built-up from smaller components, just as it is in Airbuses. Flush riveting is used throughout.

With its unique trailing horizontal stab, the empennage bears a family resemblance to the Rallye. A generous vertical fin and large rudder are mounted forward of the tail cone, with the stabilator placed aft of the vertical tail. Ventral fins, or strakes, are located on the lower fuselage just aft of the baggage bay. These directional control aids help meet spin recovery requirements. Control surfaces are actuated by push-pull tubes, which is unusual for aircraft of this category. Mooney has a similar design. But unlike the Mooney, the TB-10s pitch trim is cable-actuated. Unusual for the category, the TB-10s O-360-A1AD Lycoming is mated to a constant-speed Hartzell prop.

The TB200XL, added to the line in 1993, is powered by a Lycoming IO-360-A1B6 rated at 200 HP. When first introduced at a premium of about $6000, buyers got a slight improvement in climb rate, especially in high density altitude conditions and a marginal increase in cruise speed (about 3 knots) in exchange for less payload and a gallon or two more fuel burned per hour. Operating and limiting weights remain the same as the TB-10.

There have been minor changes to the TB-10 over time, most in response to field service problems or airworthiness directives. However, earlier versions are restricted by a maximum landing weight of 2407 pounds (this was increased to 2535 on later models) as well as maximum baggage bay load of 100 pounds, later raised to 143 pounds. Its worth carefully reviewing the data for each aircraft, since there also are 5-pound variations in maximum operating weight (2530 vs. 2535 pounds).

In 1989, the electrical system was changed to 28-volt capacity. In that year the company also started using polyurethane paints in place of the acrylic exterior finish. In 2000, SOCATA brought out the so-called GT or Generation Two singles. Theyre basically the same airframe, but with a larger passenger compartment thanks to a carbon-fiber cockpit overhead. The vast majority of airplanes in the U.S. market are generation one aircraft. In 2004, Tarbes production ceased but SOCATA is considering restarting it in Romania.

Market Scan

SOCATA'S GT Line

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The Tobago barged into a rather well-served segment of the market, the four-place cruiser field. That would include Pipers PA-28-181 Archer II, the Grumman/American General AG-5B Tiger and the Cessna 172 Skyhawk and possibly the Cardinal.

Comparing the Tobagos resale values against these relative stalwarts is somewhat difficult to do because there are relatively few sales of Tobagos in the U.S. to generate accurate sale-price data. Compared to the Archer, the Tobago hasnt done well in depreciation, however. It sold for about $100,000 new in 1986 and has now depreciated to $58,000, holding 58 percent of its value. By comparison, a 1986 Archer II also sold for about $100,000, but its

SOCATA'S GT Line

Joachim Lippl

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resale value is $78,000 or 78 percent of the new cost.

The speed king of the group, not surprisingly, is the Tiger. In most other measures, such as service ceiling, rate of climb and required field length, the airplanes are all close enough in performance to call them even, especially in the hands of the average pilot.

The Tobago easily wins the elbow and shoulder room contest with its 50-inch-wide cabin. And, surprisingly (because it pulls that wide fuselage through the air), it wins or at least finishes respectably in the theoretical range derby. It also wins the pizzazz race with most people. An owner writes: “There is hardly anywhere I land that the plane fails to draw admirers.” One pilot who has owned two TB-10s says: “They are, by far, the most comfortable, stable, well-handling and attractive planes in their class. Modern, well thought-out, plenty of attention to detail, human factors engineering and just plain good sense.”

Loading

Tobagos are equipped with as much as 200 pounds in avionics and accessories, although the average is closer to 150 pounds. Even the most plush can legally accommodate three 170-pounders with full fuel, although one owner dubs his a “very good two-person cross-country plane.”

Unique to the Tobago is that its approved to carry up to five people and quite a few TB-10s have a third seat belt installed in the middle of the rear seat. Otherwise, the option is two bucket seats in the rear. Three children or small and narrow adults can be carried back there, although no one would want to make it an all-day trip in the backset. Maximum load rating is 386 pounds for the rear seat. The baggage area is generous and can be reached from the rear seats in flight. The biggest shortcoming is the external door, a triangular opening that makes it necessary to load large bags through the cabin. The size and shape are dictated by the semi-monococque tub structure. The rear seat can be removed to provide a really big baggage bay.

Well-equipped Tobagos have a forward CG bias. One owner says that with just two aboard with full fuel, the forward CG limits the load to 400 pounds in front. By the same token, that makes keeping a full-seats-plus-baggage airplane easier to load within limits.

PERFORMANCE, HANDLING

Normal cruise power setting of 65 percent yields about 117 KTAS with a book fuel burn of 8.2 GPH at best economy or about 9.7 GPH at best power mixture. One owner says he averages better than 123 knots true while burning 9.1 GPH. Another uses a normal power setting of 23/23, which works out to about 68 percent power at 4000 feet and a TAS of roughly 122 knots.

Ground handling is easy, and the only step some pilots may find different is the use of 10 degrees of flaps for normal takeoff. Initial rotation and climb airspeed and pitch control require close attention initially. Some pilots attribute this to the semi-reclining seat position.

Pilots also have commented on the fairly large yoke. It gives a good, solid feel. More important, it adds leverage for more effective roll control and like Mooneys, with the torque tube control run, control input can be heavy compared to other airplanes in the category. Control input and response is quite linear, with the level of effort required increasing with airspeed, as it should. Control harmony is about average. Next to roll, pitch is heaviest, but pitch trim is quick and effective.

The TB series does not share the leading edge slats of the Rallyes, but it nevertheless exhibits good controllability at low speeds. Pilots new to the airplane should be careful not to let that benign behavior lull them into ignoring vertical speed. High sink rates can develop even with the airplane fully responsive to control input. “You better have some altitude because you will get a sink rate in excess of 750 FPM. This is not a glider,” one owner wrote.

The flaps are effective, too, and the Tobago has very good short-field handling characteristics, with plenty of stabilator power to hold the nose off for soft fields (the manual has some helpful information to use for operations from other than hard-surface runways).

COMFORT

Comfort is a strong suit of the TB series. Visibility is tops. Cockpit display and layout are good and quite logical in most respects, although some pilots find the push on/push off electrical switches and vertical engine, fuel and electrical gauges idiosyncratic. The generally excellent arrangement eliminates a lot of the hunting and head-ducking for switches and gauges that occur in many cockpits. One owner says of the cockpit “The arrangement of instruments, avionics, controls, caution lights and gauges is elegant, complete and efficient.”

Varying to some degree according to the interior and type of seats installed, all Tobagos reflect better than average attention to comfortable seating for pilot and passengers. Taller pilots should check out the seats before falling in love with a particular airplane, however. Earlier seats were thicker and higher, leaving less headroom. Some do not adjust (tall pilots have to recline their seat back to clear the overhead). Later models include both vertical adjustment and thinner, but more dense padding.

Visibility from the rear seat is almost as good as from the front, so the Tobago is a good sightseeing airplane. One owner on his second Tobago says: “Cabin roominess and elbow room rival that of most twins, making other four-place singles seem like sardine cans.”

Entry and exit are better than average, as well. The gull-wing doors are exotic (and must be treated like huge sails in any kind of breeze), but they open wide to make access to the rear seats fairly simple. The wing walk is narrow, so the pilot should take pains to brief people who are unfamiliar with the airplane on entry and exit procedures its too late once they are up on the wing, wrestling with the door. The doors are not supposed to be cracked for cooling on the ground with the engine running, but a lot of pilots ignore the prohibition. It does point up the drawback of the generous window area: it can get hot in the cabin. Sun shields or screens are a must. In flight, air flow and distribution is quite good for both cooling and heating.

MAINTENANCE

The good news is that the Tobago makes use of a lot of standard parts that are easy to obtain, from its avionics to the powerplant. Also, the simple construction of the airframe helps. All told, parts have not been much of a problem to come by. The TB-10 cowl is cumbersome to remove. The top half exposes the engine and accessory bay between it and the firewall, providing good maintenance access. But normal preflight inspection is limited to peeking through the air intake and exhaust openings and peering down the dipstick inspection door. Bird nests can be a problem. The instrument panel is built in three modules that can quickly be released and folded down for maintenance. In later-model TB-10s, there are access ports just forward of the base of the windshield, too.

Recurring problems are mentioned in a few service difficulty reports, such as one about cracking propeller spinners and spinner bulkheads and leaking fuel quantity floats. Other problems mentioned are windshield crazing, avionics static from instrument panel lighting, lots of cracking fiberglass (wing tips, gear fairings) and minor hydraulic leaks. Again, however, owners rate manufacturer support highly. One owner offered this tip: Put together a metric screw kit for all fuselage inspection plates and fairings: “It seems that most mechanics would rather strip your threads by forcing in an SAE screw than try to find a proper replacement.”

Owner Feedback

Heres some perspective on flying a Tobago in Germany. I wont bother you with the costs, just assume they are higher than in the U.S. We fly this airplane with a group of five pilots.

SOCATA'S 200XL

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The biggest plus first: The thing is big. Huge. Cabin width is similar to a Bonanza, if you have the bench in the back. Theres a two-bucket-seat variant, too. It will fit three small people which will then feel as if youre a 172, spacewise. The baggage compartment will take a lot of stuff, although the door is on the small side. But you can always load over the back seat.

Now for the biggest negative: The thing is big. Huge. Those 180 horses wont get you anywhere fast. The cabin is very wide, which makes for a lot of drag. We plan on 110 knots cruise, at 9.2 GPH. Youll get to where you want to go slowly, but youll get there in style.

Which brings us to the main point about the Tobago: The airplane has style in spades. From the overall sleek design to the gullwing doors to the spacious interior with excellent visibility from all seats, youd never even think of calling this a spam can. A lot of this has to do with the fact that the design is much younger than your average spam can, being from the late 1970s and early 1980s.

Mechanics very much like the size of the engine compartment, since it is the same as in a TB-20, where it holds a six-cylinder. With the O-360 in there, that leaves a lot of room to work with.

Our airplane, callsign D-EDXW, is serial number 462, built in 1984. It has the small panel on the right side and is rather fully equipped, with a Garmin GNS430, GMA340 audio panel and GTX330 Mode-S transponder, soon to be mandatory here for IFR. In addition, theres an S-TEC System 50 autopilot with GPSS add-on, a GEM-602 engine analyzer, a WX-500 playing on the GNS430 with heading stabilization from the DG.

Panel space is somewhat limited, especially if you wanted to install a big screen of some kind. Some of the instruments (e.g. the engine cluster) and switches as well as the symbology used in labeling them is, well, very French and takes some getting used to.

Our equipment, in addition to the airplanes inherent stability, makes it a great IFR platform. The controls are firm in their movement, owing to the pushrods used instead of cables. But, all this stuff reduces useful load, including fuel, to 822 pounds. Thus, we never top the tanks after flight so that the next pilot has the possibility to trade range for load. The CG envelope is generous. The tanks are integral and there are markings on the main spar so that you can fill the tanks to the desired level very easily, a great feature.

Ive read somewhere that windshield crazing is a problem with Tobagos and ours sure shows it. We are thinking of getting a new one next year. There are alternative sources to the prohibitively expensive original from SOCATA. LP and at least one other vendor has a TB-10 windshield.

Some people consider the gullwing doors a safety issues for two reasons: One, you dont really want one to open in flight. There has been a case where the door ripped off and hit the stabilizer. And two, if you ended up with the airplane turned over, you might not be able to open them. For point two, the official solution is to kick out the rear windows, which for me makes it a non-issue. For point one, well, take extra care.

A great resource for owners and renters is www.SOCATA.org, with its user forum.

Thomas Borchert

Hamburg, Germany