Willi is on the left, with classmates at the Bomber school in Thorn on the Vistula River in the Generalgovernment, 1940. Man in center is Koenig who became a pilot in Willi's squadron and was killed during the dangerous January '43 Welikije Luki mission. From Life of WLK:
On December 10, I fly with Lt. Koenig on my starboard side in bright sunshine over white glaring ground, not higher than 60 ft., and experience heavy anti-aircraft gun fire. Koenig steers off and nearly collides with me.