The letters TB within the designation stands for Tarbes, the French city where the aircraft is manufactured. The TB series planes have come to be known as the "Caribbean Planes", due to the island naming convention adopted for the various models, though they are not often seen flown in that region. All aircraft (with the exception of the TB9) have a constant speed propeller. The TB series have become widely used training and touring aircraft and are often used for instrument training. They are defined by their superior (and contemporary) fit and finish and interior size; compared to other four-seat single-engine aircraft, they are relatively roomy at 49 inches (124 cm) at the shoulder, plus or minus. In part, this is due to the fuselage having a pronounced "round out" above the wing. Adding to the actual spaciousness, the side windows extend up well into the roof line, giving the Socata an airy feeling.[2] Due to the larger fuselage, and relatively heavy weights, TB series aircraft have lower performance figures than a similarly sized and powered but narrower aircraft, and the trade-off of speed for comfort is often cited by TB owners. For details of the development, design, operational history and 23 variants, click here. The specifications below are for the TB-10 Tobago. TB-9 Tampico TB-10 Tobago TB-20 Trinidad TB-21 Trinidad TB30 Epsilon (Military trainer) SOCATA TB Cockpit