Type Two seat touring aircraft
Engine 1 Walter Mikron
Dimensions Length 7,15 m , height  ,  span 11,50 m , wing area 14,0 m2  ,
Weights Empty 240 kg, loaded 560 kg , max. take off weight  
Performance Max.. speed 195 km/h , cruising speed  , range 700 km, endurance  , service ceiling 4000 m  , climb
Type Werk.Nr Registration History
OK-BEI
In parallel with the construction of the Be.50 Beta family, the company "Benes & Mraz Tovarna na Letadla" began the development of an aircraft distinguished by the placement of crew members (side by side) and with a lightweight wing design.

To test the design, two very similar single-seat aircraft were built in 1936, differing only in the power plant and small structural details.

The first aircraft completed was the Be.501 Bibi   (OK-BEI) with a 45 hp Walter Mikron II engine. (33 kW) . The second - Be.502 Bibi (OK-BEL) received a proven Walter Minor 4 engine with 85 hp. (62 hp).

Be.501 and Be.502 managed to take part in several competitions. No further development followed as the developers switched to the more advanced Be.550. After the annexation of Czechoslovakia, the aircraft were used in Luftwaffe flying schools.