'The first BAT (5) was built in 1953, when most other carmakers had never even imagined tailfins and long before there was a Batmobile on television,' said Mounger. 'The BAT 7, built in 1954, was even more radical in design with huge curved tailfins. And the final BAT—BAT 9—was built in 1955 with reduced wings and a design that was closer to a production sports car.
The famous and renowned coachbuilder Bertone was tasked by Alfa Romeo to build an aerodynamic experimentation to measure the effects of streamlining on a car's performance. Scaglione was tasked with aiding in the creating of the design. The vehicle was dubbed the B.A.T. 5 representing 'Berlinetta Aerodinamica Tecnica'. 'Berlinetta' means 'small sedan' or more precisely, 'coupe.' The design featured rear fenders and curved fins, truly a unique design. It was built upon an Alfa Romeo 1900 chassis.
The B.A.T. 7 was created a few years later and was again an experiment in aerodynamics. The B.A.T. 7 was even more radical in design and was adorned with very large curved tailfins.
The final B.A.T. Concept, the B.A.T. 9 was completed in 1955. It continued the experimentation with aerodynamics but not as exaggerated as the prior models. The body styling took into account future production requirements and is arguably the most attractive of the B.A.T. automobiles.
Today, all three B.A.T. Concept Cars belong to the Cars International Ltd., a specialty dealer located in Canary Wharf, London UK.
Another prototype vehicle, the Giulietta Sprint Speciale was introduced to the public at the 1957 Turin Motor Show and later went into limited production until mid-1959. The vehicle was based on the B.A.T. cars and built by Franco Scaglitone, Bertone's chief designer.
Alfa Romeo provided a five-speed gearbox and a powerful four-cylinder engine that produced more than 90 horsepower, good enough to propel the car to a top speed of 125 mph. The performance and handling aspects were phenomenal. The bodywork was steel with an alloy hood and trunk lid. The interior was elegant, comfortable, and functional. There was adequate space for luggage. By Daniel Vaughan | Oct 2005
In 1955 Bertone turned in the final design for the B.A.T. project, a series of prototypes which represented the peak of styling creativity at the time. The B.A.T. 9 did away wîth the marked wing lines of the previous models in favour of a cleaner, more sober line. The tail fins, which in the other two models, 5 and 7, had a real wing-like look, were sized down into two small metal plates. Bertone transformed the highly creative styling of the two previous B.A.T. models into design credibility, abandoning the extremes of the other designs. The more rational, less artistic design of this prototype, however, does nothing to diminish Bertone's creative contribution to the Italian school of bodywork design.Source - Bertone
The Giulietta Sprint success story in 1953 and 1954 was not the only thing bringing Bertone fame and fortune at that time. In the mid-fifties the reputation of the Turin bodywork builder owed much to the revolutionary B.A.T. 5 line, and following on from that the B.A.T. 7 and the B.A.T. 9. The Berlinetta Aerodinamica Tecnica 5, or B.A.T. 5 takes its general inspiration from the 1952 Abarth 1400 coupe, and its mechanics from the Alfa 1900 Sprint. The acronym was a great hit in the English-speaking world because the car was actually reminiscent of a bat, wîth its tail shape hinting at two tucked-in wings.
The design of the model was based on a study of aerodynamics. The shape of the front in fact aims to eliminate the problem of airflow disruption at high speeds. The design also aims to do away wîth any extra resistance generated by the wheels turning, as well as achieving a structure which would create the fewest possible air vortexes. In practice these rigorous criteria would allow the car to reach 200 km/h wîth the 100 Hp engine mounted as standard. The design that Bertone came up wîth was for an extremely light car (1100 kg), the ultimate in streamlining, wîth side windows at a 45 degree angle respect to the body of the car and a large windscreen which blends in perfectly wîth the almost flat roof. The most surprising part of the car has to be the tail, wîth the length-ways rear windscreen divided by a slim pillar, and the two fins tapering upwards and slightly inwards, for a highly aesthetic finish. There was no shortage of positive feedback: the car was an immediate hit for its aerodynamics and noteworthy stability at high speeds. Bertone had solved the problem of aerodynamic stability, creating a car wîth an excellent index of penetration.Source - Bertone
B.A.T. 5 first appeared at the 1953 Turin Motor Show and was an immediate hit. The aerodynamic Alfa was an extremely light car of 1,100 kg, with a 0.23 cd (drag coefficient). This allowed it to achieve a speed of 200 kph with good high speed stability, using only a 100 hp engine. The metallic charcoal B.A.T. features enclosed wheels, a teardrop-shaped cabin, and striking tailfins.
Alfa Romeo commissioned the famed coachbuilder, Carrozzeria Bertone, in Turin Italy, to design the three aerodynamic studies known as the B.A.T. cars to explore the effect of streamlining on a standard Alfa 1900 Sprint chassis. The goal was to investigate and apply advances in vehicle aerodynamics.
These road-worthy concepts were called Berlina Aerodinamica Technica, or B.A.T. for short. They were designed by Franco Scaglione for Bertone and Alfa Romeo, to be presented at the Turin Auto Show in 1953, 1954, and 1955. Each B.A.T. concept was successfully introduced to great acclaim at the time. Although the cars were too extreme to make production intact, their influence and aerodynamic lessons were incorporated in the stunning, Scaglione-penned, Alfa Romeo Giuletta Sprint Speciale.