Hi,
http://www.luftwaffe.cz/ehlers.html
about Ehlers, extract says…However, he was forced to belly-land his damaged Bf 109 E-4 “Black 6” at Colembert following aerial combat over England on 15 August 1940. Ehlers participated in the invasion of Russia.
I see photos of this aircraft on Asisbiz website captioned Ehlers, including an NCO pilot walking past wingtip whilst an officer wearing highboots rests one on the wing leading edge.
However, in ‘On Target Special’ The Battle of Britain Camouflage and Markings, Peter Scott and Gary Madgwick, The Aviation Workshop Publications Ltd 2010 page98 there is a profile of black 6 with red tatzelwurm on cowling, yellow wingtips. White segmented spinner with red tip, yellow rudder, mottled sides more dense just fwd of cross saying Obfw Keller. Landing accident Colombert 15 Aug 1940.
Another book has this profile (same artist) also Obfw Keller.
So why two names appearing for the same aircraft ?
The profile appears to be for that aircraft in the photos, correct me if I am mistaken.

Thanks
BOBC