do fighters/bombers add thier technology value to arrive at the drm?
ex: level 2 fighter = -3 drm? or is it just count the number of aircraft each getting a -1 up to a max of -2?
Per 10.3.3, fighters/bombers only add to range, air combat strength and their strat bombing die roll...not to their ground support drm.
10.3.3: "Aircraft: Add +1 to the range and total air combat strength to that nation’s air units for each Tech level. If more than one unit is in combat, add the Tech bonus once to all units, not each one. They also receive a Decoy Fighter Air Unit at Tech level 1 and a Decoy Bomber at Tech level 3. A +1 for each Tech level is also added to the damage via Strategic Bombing."
13.2.3: "Apply any weather DRM (-1 for Snow, -2 for Mud) and any DRM for fighters and bombers remaining in the hex, for both the attacker and defender (maximum of two each, +1 or -1 per air unit.)"