René Bonnet Aérodjet LM: The Radical Long-Tail Prototype of Le Mans 1963

Technical Outlier - Endurance racing in the early 1960s functioned as a laboratory for ideas too radical for road cars. At Le Mans, efficiency, balance, and aerodynamics often mattered more than raw power, especially for small constructors. René Bonnet embraced this challenge in 1962 with an early mid-engined prototype, setting the conceptual foundation for a more extreme evolution that would emerge the following year as the Aérodjet LM. 

The René Bonnet Aérodjet LM competed at the 1963 24 Hours of Le Mans under Bonnet’s own banner with Matra-built fiberglass bodywork, appearing in at least four entries—numbers 41, 51, 52, and 53—while its total production remains unknown. (Picture from: RMStyle-24lm)

The Aérodjet LM of 1963 was not a direct carryover from the 1962 car, but it was shaped decisively by the lessons learned there. Experience on the long straights of Le Mans highlighted the limitations of drag and high-speed stability, prompting Bonnet to pursue a far more aerodynamic solution. The result was a long-tail body designed to slice through the air efficiently, with some units featuring enclosed rear wheels to further reduce drag. 

The René Bonnet Aérodjet LM appeared in two configurations, LM5 and LM6, with LM6 distinguished by its more extreme long-tail body and occasional rear-wheel covers for greater high-speed stability. (Picture from: WorldCarFromThe1930sTo1980s in Facebook)

René Bonnet entered the 1963 24 Hours of Le Mans under his own banner, with support from Matra for the fiberglass bodywork. Racing documentation shows at least four Aérodjet LM entries, numbered 41, 51, 52, and 53, though the exact total number of cars ever built remains unknown. None were intended for production; they served as rolling testbeds for aerodynamic and mid-engined concepts that would later influence the Djet and shape Matra’s future sports cars. 

The René Bonnet Aérodjet LM stood out visually with its elongated, low-slung body, and in LM6 form pushed aerodynamics to extremes while retaining the mid-engined layout first explored in 1962. (Picture from: Fastestlaps)

Within the Aérodjet LM family, two main configurations are recognized: LM5 and LM6. LM5 retained a more conventional aerodynamic profile, while LM6 featured the more extreme long-tail design and, in some cases, rear-wheel covers to enhance high-speed stability. Both variants shared a lightweight tubular chassis and Renault-based four-cylinder engines tuned by Gordini for endurance performance. 

The René Bonnet Aérodjet LM was mechanically defined by modest-displacement Renault engines tuned for endurance, with Gordini cylinder heads improving breathing and durability for sustained racing over 24 hours. (Picture from: Invaluable)

Visually, the cars were striking: elongated bodies with a low, aggressive stance, designed to maximize airflow efficiency. The LM6 in particular demonstrated Bonnet’s willingness to experiment beyond conventional racing norms, pushing aerodynamics to extremes while maintaining the mid-engined layout pioneered in 1962. 

The René Bonnet Aérodjet LM stood out visually with its elongated, low-slung body, and in LM6 form pushed aerodynamics to extremes while retaining the mid-engined layout first explored in 1962. (Picture from: WorldCarFromThe1930sTo1980s in Facebook)

Mechanically, all Aérodjet LM cars used modest-displacement Renault engines optimized for endurance rather than outright speed. Gordini cylinder heads improved breathing and durability, allowing the cars to sustain competitive average speeds across 24 hours of racing. The engineering philosophy mirrored the aerodynamic one: precision, efficiency, and purpose-built experimentation. | eKcbKMgk8EI |

Today, the Aérodjet LM remains a rare and often overlooked milestone. Its multiple configurations, small numbers, and experimental design reflect a brief moment when innovation was driven by necessity, experimentation, and belief rather than scale or fame, and it continues to be recognized as a direct precursor to the production Djet and the future sports car programs that Matra would later develop. *** [EKA | FROM VARIOUS SOURCES | INVALUABLE | CLUBDJET | LAAUTOMOBILEANCIENNE | RMSTYLE-24LM | WORLD CAR FROM THE 1930S TO 1980S IN FACEBOOK ]

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