Aerospatiale TB-10 Tobago

French engineering has always been a little bit different, and this single is no exception.

We don’t get to see much French hardware in this country any more, but those of us who remember such wonders as the Citroen automobiles with their hydraulic suspensions, or the old Renault 16, the interior of which could be stripped out in minutes without tools, will also recall that the French have their own distinctive way of doing things. The engineering is elegant or odd, depending on your point of view.

The SOCATA Caribbean series, when it was introduced in this country in the mid-1980s, was the embodiment of that unique way of doing things. Markedly different from anything wed ever seen, the French imports had a lot to offer, and they even managed to successfully buck the downward spiral that all but killed off American light aircraft production.

What the Caribbean series really brought us, though, was a fresh look at the design of light aircraft. They use the same engines as others, and perform about the same, as well. But there’s considerable innovation here: a high degree of parts interchangeability, superior ergonomics in some respects, and simple, efficient construction. Whereas the typical Cessna or Piper – even a mid-1980s model – clearly shows its late-1950s roots, the Caribbean series looks far more modern.

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 exotic high-performance automobiles. Most pilots agree that the gentleman earned his fee. Good human engineering combines with maintainability in an excellent, integrated design.

The company
Technically, the Tobago is not made by Aerospatiale, but by SOCATA, or The Societ de Construction dAvions de Tourisme et dAffaires, 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 1995, SOCATA began work on a new generation of aircraft to replace the Caribbean series. The new MS series (Morane Saulnier again) has essentially the same airframes, but makes use of an unusual new engine developed in conjunction with Renault. It boasts a single-lever power control, computerized management and, most notably, the ability to use jet fuel.

History
The Caribbean series consists of three basic airplanes, the TB-9 Tampico, for the low-and-slow trainer (read Piper Warrior) 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 TB21TC turbocharged retractable and the 200-HP TB200 Tobago XL. All look similar, because the airframes are, in fact, virtually identical.

Though they didn’t arrive here until the mid-1980s, Aerospatiale announced the TB Caribbean series at the 1977 Paris Air Show. The TB-10 Tobago was the first model certified, in 1979. The new series was developed to replace the modestly successful STOL Rallye series. Rallyes didn’t make it over here, but they’re quite commonly seen in Europe. The bad experience the company had with the Rallye in North America seems to have affected the introduction of the Caribbean series here: it was very tentative at first.

After a TB-10 was taken on a market survey tour of cities 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 Aerospatiale’s well-established and ongoing helicopter operations.

In a way, the timing couldn’t have been worse. The mid-1980s were a time when most American lightplane manufacturers were finally admitting defeat and shutting down their production lines. Still, the company managed to sign on enough dealers and sell enough airplanes to keep the venture going, even though it has been touch and go.

The production scheme was a bit cockeyed for the first several years. 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 (a few were ferried, however). Starting with the TB-9 Tampico in 1992, a production facility opened here.

SOCATA doesn’t actually assign model years, with the model years determined by their delivery dates. Average equipped prices for the TB-10 currently range from $78,000 to $162,000; TB200XLs, which were introduced in 1993, go for $138,000 to $225,000.

Airframe
The TB airframe is a clever design that blends low-slung, elegant lines with simplicity that stems primarily from designing for efficient manufacturing and trying to minimize the parts count. A parallel design objective was to simplify maintenance and reduce operating and life cycle costs.

There is 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; flush riveting is used in the wing skins.

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. Pitch trim is cable-actuated.

Aerospatiale sales literature points out that 80 percent of systems and components other than the airframe are manufactured in the United States. This includes major items such as the engine and electrical systems, avionics, wheels and brakes.

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. For about $6,000 more (base price in 1993; equipped prices for the TB200XL were quite a bit higher), buyers got a slight improvement in climb rate, especially in high density altitude conditions, and a marginal increase in cruise speed (about three 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 2,407 pounds (this was increased to 2,535 on later models), as we’ll as maximum baggage bay load of 100 pounds, later raised to 143 pounds. It is worth carefully reviewing the data for each aircraft, since there also are five-pound variations in maximum operating weight (2,530 vs. 2,535 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.

The Competition
The TB-10 was launched into the middle of what is the most populous (and formerly most competitive) category of light aircraft: four-place, fixed-gear singles. Narrowing the competition to fairly late-model airplanes with 180-hp engines, the Tobago faces some stiff and numerous challengers in the used-aircraft market: Piper PA-28-181 Archer II, Grumman/American General AG-5B Tiger, Cessna 177B Cardinal and the Beech C23 Sundowner.

Unfortunately, its tough to compare relative values for this group, since some had already gone out of production when the Tobago was being built. For those airplanes that were being produced at the time, the Tobago has held its value somewhat better. An average-equipped 1992 Tobago has retained 74 percent of its new value; the Archer has kept 60 percent, and the AGAC Tiger has retained only 58 percent.

The speed king of the group, not surprisingly, is the Tiger. But the TB-10 is second (75 percent cruise is 127 knots versus 139 for the Tiger, with the Archer third at 125. In an unrealistic measure of payload with full fuel, the Tobago is tied for second with the Tiger; the Archer wins. Its unrealistic because its based on basic empty weight rather than equipped weight.

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 the theoretical range derby at 635 nm with the Arrow and Sundowner tied for second at 565 nm.

It also wins the pizzazz race with most people. An owner writes: There is hardly anywhere I land that the plane does not fail 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, we’ll 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.

It is 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. Three children or small and narrow adults can be carried back there, although no one would want to make it an all-day trip there. Maximum load rating is 386 pounds for the rear seat.

The baggage area is generous: far larger than its 100- or 143-pound limit would seem to need. It can be reached from the rear seats in flight. The biggest shortcoming of the baggage bay 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
At gross weight, the TB-10 needs a total of 1,657 feet to clear 50 feet and 1,394 to land over a 50 foot barrier. Maximum rate of climb is 790 FPM, although the deck angle – and visibility – suggest using cruise climb procedures. A Tobago owner says the procedure settles down to about 500 FPM above 3,000 feet using 2,500 RPM and 25 inches MP.

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 4,000 feet and a TAS of roughly 122 knots.

Factory numbers say 75 percent power yields 127 KTAS and 4.9 hours endurance (9.5 gph) with 45 minutes reserve; 65 percent 117 knots for 5.6 hours (8.2 gph). Those figures are good for still-air ranges of 622 and 655 nm.

Handling
Procedures are straightforward, from preflight to shutdown. 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 might 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 (those ailerons are small). That, combined with the torque tube control run, makes control input heavy compared to many 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. Stalls are very soft. Power-on stall requires a very high pitch, one owner reports. Another says: Stalls are definite and we’ll behaved with the stall warning bell and gentle buffet indications. The problem is getting the Tobago to stall at all. For power on stalls I almost have to stand it on its tail before it stalls and drops its nose like an obedient puppy.

Pilots new to the airplane should beware that the benign behavior should not 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).

Demonstrated crosswind component is relatively high at 25 knots. Thanks to its comparatively high wing loading, it handles turbulence well. It is a well-mannered, predictable instrument platform. Both in capability and response, the Tobago is a good touring airplane.

Comfort
Comfort is a strong suit of the TB series. Visibility is tops. Cockpit display and layout are very 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, or at least different. The generally excellent arrangement eliminates a lot of the hunting and head-ducking for switches and gauges that occur in many cockpits.

An 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 (and note, there are two) 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 tend to 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 considerations
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. (They come in different sizes, depending upon the avionics and other cockpit accessories installation.) In later-model TB-10s there are access ports just forward of the base of the windshield, too.

Our scan of service difficulty reports didn’t turn up much, though we have seen several reports that mention corrosion, or conditions conducive to it; this in a design that the marketers brag undergoes three separate corrosion-protective procedures before assembly. Several, including a problem with insufficient or missing aft fuselage weep holes that relates to the potential for corrosion and another related to exhaust clamp failures, are covered by service letters or bulletins.

Recurring problems are mentioned in a few of the reports, such as one about cracking propeller spinners and spinner bulkheads and leaking fuel quantity floats. An SDR on cracking spinners mentions seven replacements on one aircraft, suggesting a potential dynamic balance and/or propeller tracking problem.

Three instances of seat belt attach point corrosion were attributed to leaks in doors and windows, suggesting that investment in a cover is a good idea for more than temperature control. One owner mentioned chronic spinner and bulkhead problems; two reported fuel gauge problems. 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 mentions that most large FBOs have TB manuals on microfiche, but many are listed under SOCATA rather than Aerospatiale. He has a good 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.

There are a few notable type-specific ADs, three of which cropped up in 1998. One earlier directive (87-22-2) calls for periodic inspection of an aft fuselage frame. The three more recent ones cover the aforementioned seat belt attachments, periodic inspection of the main landing gear support ribs and inspection of the wings rear attach points for cracks that may lead to failure. This sudden rush of airframe ADs is a bit troubling, and serves to point out that even aircraft that feature so-called advanced design are not immune to problems.

Also, the TB-10 (but not the TB200XL) is subject to 98-2-8, which calls for inspections of the crank for corrosion pits. If any are found, 100-hour repetitive inspections are mandated until the next overhaul, when it must be replaced.

In closing
The Tobago is a good-looking design that combines good ergonomics for everyone on board with one of the best small-airplane cockpit layouts you will find.

It is a good cross-country machine that handles we’ll in turbulence, is a good IFR platform and also has good low-speed flying characteristics.

Owner Comments
I have owned two Aerospatiale Tobago TB-10s and must say that I believe they are, by far, the most comfortable, stable, well-handling and attractive airplanes in their class. Almost everywhere I land the plane does not fail to draw admirers and onlookers. The Tobago is truly a modern, well-thought-out aircraft that shows plenty of attention to detail, human factors engineering and just plain good sense.

Cabin roominess and elbow room rival that of most twins I’ve flown, making other four-place single-engine aircraft seem like sardine cans by comparison.

All these factors plus high-back bucket seats, two gull-wing doors, under the hand power quadrant controls and excellent all-round visibility make the Tobago the closest thing to flying a car I have yet found.

While some of the performance characteristics could be better, you have to understand that this is really a runabout class machine and not a Trinidad, its high-performance big brother. Leaping off the runway at 65 knots offers an impressive 650-900 fpm climb that soon comes down to a steady 500 fpm after 3,000 feet. I climb out at 25/2500, after the first 1,000 feet, and pull back to a reasonable 21-22/2300 for cruise.

The Tobago trues out at the book values of 123-125 knots and averages an impressive 9.1 GPH fuel burn that includes everything from engine start to shutdown. I calculated the above figure by using total fuel purchased divided by the Hobbs time over a six-month period. I always plan and file using a true airspeed of 120 knots and burn rate of 10 GPH and never have had a problem with endurance. Oil consumption averages about 10 hours per quart.

Coming down is as simple as dropping the nose for a 140-knot cruise descent or cutting the MP to 13-15 inches, and the Tobago comes down as if it were riding on rails. Engine-out glide speed is 86 knots, but you better have some altitude because you will get a sink rate in excess of 750 FPM. This is not a glider, folks.

The massive rudder, dual strakes and offset stabilator (fancy elevator) really help in low-speed control situations. Stalls are definite and well-behaved with the stall warning bell and gentle buffet indications. The problem is getting the Tobago to stall at all; the plane just wants to keep on flying. For power-on stalls I almost have to stand it on its tail (appreciate the high back seats) before it stalls.

As most anyone will agree, airplanes are black holes that we throw money into but maintenance costs on the Tobago are pretty reasonable. Although the aircraft itself is French made, Aerospatiale uses a great amount of standard, unmodified, equipment including Lycoming IO-360 engines and King avionics. Part availability has not been a problem and parts are generally stocked by most major distributors such as Aviall.

I have had a couple of chronic problems with spinners and back plates developing cracks and with inaccurate fuel gauges. In both cases the Aerospatiale team in Grand Prairie, Tex. stepped up to the plate and stood behind their product, supplying redesigned replacement parts at cost and under warranty.

Other problems I’ve had include crazing on the Plexiglas windshield, static on the radios caused by the florescent tube light for the panel, an intermittent miss in the engine that we still are trying to find, cracks developing on the wheel and strut fairings and the ever-popular wingtip cracks and some frozen locks.

If you can put up with controllers calling you a Toboggan every once in a while, its definitely a winner.

George Photakis
Columbus, Ohio

 

We are six joint owners of a 1986 Tobago with a 180-HP Lycoming. Performance is very similar to a Cessna 172. In formation flying with Cessna 172s, the Skyhawks outclimbed the Tobago. But the Tobago cruised faster with similar loads. The book, and our experience, show 114 KIAS and 9.6 gph at 4,000 feet, 2300 rpm and 23 inches MP (68 percent) for an IFR-equipped plane with wheel fairings.

Its been taken up to 12,500 feet with two aboard without too much trouble. Service ceiling is 13,000 feet. Relative to the Grumman Tiger, which has the same engine, its 5 to 8 knots slower.

Our Tobago is fairly flexible when it comes to loading. The cg tends to be forward, which limits the front seats to about 400 pounds total with full tanks . You can take four adults on a reasonably long tour, but you have to watch the fuel-loading more carefully.

Handling: No complaints whatsoever. Stalls are very soft. Power-on stall requires a very high pitch. Full flaps are notably effective for short field landings. Main gear struts make for very forgiving landings. No rudder trim is provided.

Comfort: Visibility front and rear is excellent except straight down through the wings and straight back through the tail. There’s plenty of shoulder room since the cabin is 50 inches wide. For the pilot who is 62 the seat has to be reclined slightly to get enough headroom. The engine controls are still easy to reach since they are located on the center console between the front seats. The seats themselves don’t have vertical adjustment – just forward/aft and recline.

On sunny days the cabin becomes a greenhouse until you are airborne. You must not taxi with the gullwing doors open. Noise levels are acceptably low to cabin occupants. The interior is car-like, makes passengers new to general aviation flying feel comfortable. We have a cabin cover to keep out the sun while parked. Costs, maintenance and parts availability averaged out over two years, operating expenses were $14.10/hr excluding fuel and reserves for the 2,000-hour overhaul. Everything except the body is standard American hardware: the engine, prop, brakes, wheels, landing/taxi lights and avionics.

Body panel screws are metric. All parts we’ve ever needed have been stocked in the U.S. and available overnight. We had to put together our own screw kit. Its important to have extra screws on hand and let mechanics know that you have them. It seems that most mechanics would rather strip your threads by forcing in an English screw than try to find a proper replacement.

We’ve not had any repairs that would be considered peculiar to the Tobago – brake fluid leaks, strut leaks, small electrical problems, broken vent control. Having the landing/taxi lights on the wing are a big plus. We’ve only replaced one bulb in three years.

Our experience has been that large FBOs have manuals for the Tobago on microfiche. Note that they are listed under SOCATA, not Aerospatiale. The airplane manual is excellent, with lots of performance data and detailed emergency procedures.

Product Support in Grand Prairie, Texas: Responsive, knowledgeable and committed, quick to identify the specialist required and to get you transferred to the right extension. Good also on promised call-backs. Good follow-through on manuals when ordered. In the earlier days there were problems with parts shipped from France, but with a distribution point in Texas this no longer is the case.

As for special strengths, the plane is a very good two-person cross-country plane because of the IFR equipment and handling in actual conditions. Its well-built and contains no cheap plastic. Its beauty and elegance get flattering comments everywhere. Nicely engineered, it provides a solid feel. Its automobile-style shoulder/lap harnesses work very well.

We like the fuel test cup container and other bins provided in the baggage compartment, so the pocket behind the pilots seat holds the POH instead of soiled cup and rag. Large pockets on either side of the center console are useful for stowing charts, checklists and the yoke lock.

The gullwing doors are great for access from either side. The arrangement of instruments, avionics, controls, caution lights and gauges is elegant, complete and efficient. Weaknesses include erratic fuel quantity indicators despite replacement. Excessive left tire wear, causes not yet determined. Water accumulated in the tail cone prior to drilling an additional drain.

Idiosyncrasies: Yoke does not support a standard yoke clip, but a ceiling drop-down flap with clip can be used to hold approach plates without obstructing visibility. There’s a stall warning bell rather than horn, and the bell comes through loud and clear.

Modifications: The lower seat modification will be of great value to pilots 61″ tall and above, but we suggest that a vertical seat height adjustment be added to this mod for shorter pilots.

Ned Simonis, President
Tobago Six, Inc.
Boeing Field, Seattle, Washington

 

Also With This Article
Click here to view charts for Resale Values, Payload Compared and Prices Compared.
Click here to view the Aerospatiale TB-10 Tobago features guide.