Monoplane, single-engine, with a wooden truss fuselage partially fabric-covered and a mid-wing with controllable sweep.

In 1908, the prototype of the Blériot XI was exhibited at the first air show in Paris. The numbering indicated the previous failed attempts by its French designer, Louis Blériot, in whose hands the new aircraft made its first short flight on 23 January 1909, gradually progressing to carrying out turns and flights of a few minutes.

Two original Blériots are preserved in Italy: a single-seater at the Museum of Engineering in Rome and a two-seater at the MUSAM in Vigna di Valle (RM).