The first German mass produced 109 fighter was the Bf-109E that has been mistakenly referred to as the Me-109. The Bf is the designator for the Bayerische Flugzeugwerke (BFW) (Bavarian Aircraft Works) that produced the original aircraft. In 1938 Messerschmitt took over BFW but throughout WWII German handbooks and documents referred to the aircraft as the Bf-109. By the end of 1939 the Bf-109E (Emil) had replaced all other 109 variants and equipped 13 Gruppens with 40 aircraft each. The Bf-109 was the main single-engine aircraft until the Fw-190 came along.

Late in 1938 when Hptm. Siebelt Reents became commander of 1./J 88 he had the Holzauge (wooden eye) applied in black and white to some unit Bf-109s. The meaning of the “wooden eye” was a Spanish gesture meaning “look out”. Reents only recorded one victory while in Spain, a Polikarpov I-16 on February 6, 1939. His aircraft was left to the Spanish Air Force where it flew until 1951. Reents was wounded in WWII and became a Luftwaffe flight instructor. Reents lived to an old age of 101.

Info:     BF 109E-3 "Spanish Civil War" flown by Hptm. Siebelt Reents, Staffelkapitn of 1.J/88, Spring of 1939