The Thunderbird ("T-Bird"), is an automobile manufactured by the Ford Motor Company in the United States over eleven model generations from 1955 through 2005. When introduced, it created the market niche eventually known as the personal luxury car. 

     The Second to Fourth Generation Thunderbird convertibles were similar in design to the Lincoln convertible of the time and borrowed from earlier Ford hardtop/convertible designs. While these Thunderbird models had a true convertible soft top, the top was lowered to stow in the forward trunk area. This design reduced available trunk space when the top was down.

   The trunk lid was rear-hinged; raised and lowered via hydraulic cylinders during the top raising or lowering cycle. The forward end of the trunk lid contained a metal plate that extended upward to cover the area that the top is stowed in. With the top down and the trunk lid lowered, there is no sight of the soft top.

  The overall appearance was a sleek look with no trace of a convertible top at all. No cover boot was needed.

  However, this design could present a challenge to one who is troubleshooting a convertible top malfunction. The system consists of a spiderweb of solenoids, relays, limit switches, electric motors, a hydraulic pump/reservoir, hydraulic directional valves and cylinders. While the hydraulics are not often a cause for trouble, the electrical relays are known to fail. Failure of any of the relays, motors or limit switches will prevent the convertible system from completing the cycle.

  Unlike hardtop models that utilized a conventional key-secured, forward hinged design, the convertibles combined the trunk opening and closing within the convertible top operating system. As a result of this design, the trunks of convertible models were notorious for leaking.

    A smaller two-seater sports roadster was created at the behest of Henry Ford II in 1953 called the Vega. The completed one-off generated interest at the time, but had meager power, European looks, and a correspondingly high cost, so it never proceeded to production. The Thunderbird was similar in concept, but would be more American in style, more luxurious, and less sport-oriented.

  The men and their teams generally credited with the creation of the original Thunderbird are: Lewis D. Crusoe, a retired GM executive lured out of retirement by Henry Ford II; George Walker, chief stylist and a Ford vice-president; Frank Hershey, chief stylist for Ford Division; Bill Boyer, designer Body Development Studio who became manager of Thunderbird Studio in spring of 1955, and Bill Burnett, chief engineer.



  Ford Designer William P. Boyer was lead stylist on the original 1955 two-seater Thunderbird and also had a hand in designing the future series of Thunderbirds including the 30th Anniversary Edition. Hershey's participation in the creation of the Thunderbird was more administrative than artistic. Crusoe and Walker met in France in October 1951.
 
  Walking in the Grand Palais in Paris, Crusoe pointed at a sports car and asked Walker, 'Why can’t we have something like that?' Some versions of the story claim that Walker replied by telling Crusoe, "oh, we're working on it"...although if anything existed at the time beyond casual dream car sketches by members of the design staff, records of it have never come to light.

   Although the Thunderbird had been considered a rousing success, Ford executives  particularly Robert McNamara , felt that the car's position as a two-seater restricted its sales potential. As a result, the car was redesigned as a four-seater for 1958.

  Though retaining a design as a two-door hardtop coupe/convertible, the new Thunderbird was considerably larger than the previous generation, with a longer 113.0 inches (2,870 mm) wheelbase to accommodate the new back seat. The increased size also increased the car's weight significantly by close to 1,000 pounds (454 kg).
 


  Along with a new, more rigid unibody construction was new styling, including dual headlights for a total of four, more prominent tailfins, a bolder chrome grille, and a larger, though non-functional, hood scoop. Powering the Thunderbird was a new, 300 horsepower (220 kW) 352 cu in (5.8 L) FE V8, available with a 3-speed manual or automatic transmissions.

  With 37,892 sold in 1958 outselling the previous model year by well over 16,000 units the new Thunderbird began a sales momentum previously unseen with the car.

  It was also history-making, becoming the first individual model line (as opposed to an entire company) to earn Motor Trend "Car of the Year" honors. With little more than a new grille and a newly optional, 350 horsepower (260 kW) 430 cu in (7.0 L) MEL V8 for 1959, sales climbed even higher to 67,456. For 1960, the Thunderbird was given another new grille and other minor stylistic changes along with a newly optional manually operated sunroof for hardtop models.




  Dual-unit round taillights from 1958 to 1959 were changed to triple-units after the fashion of the Chevrolet Impala. Customers continued to approve of the car as it broke sales records yet again with 92,843 sold for 1960. In spite of this success, Ford went ahead with a redesign for the Thunderbird to debut in 1961.