Why DB-3f is counted as one of the old types on 22 June 41?

[Graham Boak]

The DB-3f is simply seen as a revision to an older design. It is not part of the new design wave of Soviet types, regardless of the value of its service. You compare it with the He.111 - but that was also an old type due for replacement. Or indeed the Wellington, another old design with much service life left. The new generation of British bombers were the triad of four-engined types: the new generation of Luftwaffe largely failed to appear.

The replacement programme for Soviet types was compressed into appearing as single wave, and a similar effect can be seen in 1940 France, with a wide range of new types that just didn't make it in sufficient numbers. In the Soviet case this wave was more obvious in the fighter and assault aircraft, because of the comparative failure of new bomber designs (Pe 2 excepted).

As to why this isn't considered in the case of the Luftwaffe, this is possibly because most writers do not realise how the Me 210 was intended to replace both the 110 and the 87, with the He 177 replacing the He.111. Had these designs moved to their intended timetable then historians could indeed write about a new wave of German designs, and recognise the earlier types as "old". With no obvious new designs in the Luftwaffe for Barbarossa, there's no reason to pick out some major types as old, even though they were. (Not that the Ju 87 was that old.....)

But perhaps you need to ask the writers of the books, and I should shut up here.