As the Breguet Br.1001 "Taon" (detailed elsewhere on this site) had been drawn up to fulfill a NATO requirement for a "common" European strike fighter, the offshoot Br.1100 was reworked to fulfill a more local French Air Force lightweight tactical strike platform. Proposals for such an aircraft were sent out in the latter part of 1953 and called for a single-seat, Mach 1-capable strike fighter supporting a broad ordnance load (while, rather interestingly, maintaining its lightweight status) and a single- or twin-engine configuration (the latter endorsed because of its inherent enhanced survivability at low-altitudes). A plethora of French aero-concerns threw their hats into the ring and the group included prominent players like Dassault, Fouga, Morane-Saulnier, Nord and - of course - Breguet with its Br.1100.
Building upon the existing framework established for the NATO Br.1001 "Taon" program, the Br.1100 differed in its arrangement of two side-by-side turbojet installations (as opposed to one, single powerful unit) necessitating the use of a wider, rounded fuselage. The wing mainplanes were appropriately swept-back and set low along the fuselage sides and sweepback was also apparent at all three of the tailplane members (twin horizontal planes and a single vertical fin). An airbrake was fitted ventrally under the tail to slow the aircraft down as needed and, again, Breguet engineers elected for leading edge slats and trailing edge flaps along the wing mainplane members for enhanced controlling. The twin engine arrangement was aspirated by semi-circular intakes at each fuselage side and each engine was given its own exhaust port under the tail. A retractable tricycle undercarriage was fitted for ground-running. In the overall arrangement, the Pilot sat under a largely unobstructed canopy and aft of a short nosecone offering excellent vision around the aircraft.
The engines-of-choice became 2 x Turbomeca "Gabizo" afterburning turbojet units of 2,645lb thrust dry each and up to 3,750lb thrust each with reheat (afterburning) engaged. The dual nature of the powerplant ensured better survivability over contested airspaces should one unit be knocked out of action. With this arrangement the aircraft could hope to reach speeds of just over Mach 1.0 at nearly 33,000 feet - and 700 mph near sea level making it a fast attacker/intruder.
Structurally, the specimen's empty weight was 8,362lb against a gross weight rating of 14,430lb. Dimensions included a running length of 41 feet, a wingspan of 25.7 feet, and a height of 14.2 feet.
The proposed armament scheme was to involve 2 x 30mm DEFA 551 series autocannons and a retracting Matra-developed rocket battery launching unit in the belly as fixed, forward-firing armament. This was to be augmented with ordnance set across two underwing hardpoints (one per wing member) used to support aerial rockets, rocket pods, or conventional drop ordnance, giving the aircraft a relatively broad ordnance-carrying role.
In its finalized form, the one and only prototype to be completed for the program achieve a first-flight on March 31st, 1957. Testing revealed limitations of the design including heightened drag induced by the well-aft tail unit - restricting speeds and keeping the aircraft from sustained supersonic speeds even in level flight (which should have been the key quality of the strike fighter). With that, interest in this lightweight twin-engine tactical strike platform ultimately waned and the project went nowhere before falling to aviation history.
A second prototype lay in an unfinished state before it, too, was given up for good. The designation of Br.1100M was reserved for a proposed navalized form but this design was not furthered.