[Jens]

1. Combat loss in VVS(PVO) means:
a) shot down in aircombat
b) shot down by AAA
c) damaged destroyed at airfield
c) did not return from sortie!

2. Other loss means:
a) Accidents/Training
b) Weared

Note: Especially fighters had many train-versions (i. e. LA-5UTI) which mostly were of course non-combat losses, if so.

In 12/1944 "Fremde Heere Ost" calculated the soviet airlosses. Heer and Luftwaffe (=flying units and AAA) claimed 70.256 Airkills! "Fremde Heere Ost" even "guessed" 113.744... . These caluclations are without the claims of the german allies.

ZAMO gives for 1944 and only VVS (not PVO and so on) following figures:
Shot down in Aircombat: 645
Shot down by AAA: 1049
Did not return from Sortie: 6612!

Non Combat: ~11.000

There is of course a high propability, that most "Did not return from Sortie" airplanes, were indeed shot down by Germans anyway, let's guess two third, would made ~ 7000 kills for the Germans in 1944. IIRC alone german fighters claimed ~9000 kills.
For the observation of German fighter kills are following examples interesting:
IL-2:
Shot down in Aircombat: 107
Shot down by AAA: 583
Fighters:
Shot down in Aircombat: 508
Shot down by AAA: 376