The Rumpler B.I (factory designation 4A) was a military reconnaissance aircraft produced in Germany during World War I.

[1] The B.I was a conventional two-bay biplane with unstaggered wings of unequal span.

[2] It featured two open cockpits in tandem and fixed, tailskid undercarriage.

[3] Rumpler built 198 of these aircraft for the Luftstreitkräfte, plus 26 seaplane versions for the Imperial German Navy.

[2] Data from Gray & Thetford 1962, p.518General characteristics Performance