SilverDragon 72
Two things left:
1) Nobody ever supposed the
emergency airstrips to base 12 division Air Army. The
emergency thing means that your planes which were damaged or run out of fuel could use it as place to land for refuel/repair. Second purpose - support of small scale operations in case of emergency (main airfields destroyed or your side urgently needs the forward base). So emergency airstrips cant "base" more than one or two airdivisions.
2) You get confused by single airfield icon (in game). There is an
airfield system in real life. Typical airfield was supposed to accomodate our in game 100 plane airdivision and nothing more. So, one in game icon = lots of airfields in real life.
So, in matter of days (1-3) you can organise some short (500-600 meters) emergency airstrips or use province road system to operate 1-2 air divisions of interceptors. In matter of weeks (30+ days) you can organise the whole airfield system (1500-1800 meters strips) for one or two Air Armies fully capable of supporting its operations (from interceptors to heavy bombers). Its just a real life experience.
OK. Now lets have some fun

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1st the definition of an HOI air unit is about 100 planes - so you will need more then one (!) truck for the ground crews !
Even light interceptor (FW190, La-5) able to carry one technician aboard. And you can use one truck more than once

. But, one division is just a nine or so squadrons. 1 truck for squadron, 9 for an airdivision.
when you just make a short rebasing trip with a 12er stack of strategic bombers
Yeah, sure, just short rebasing of the 8th Air Force bomber groups

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we talk about ~ 12 x 100 x 7 (pilot, co, tail-gunner, and ~ 4 more men on the guns) 8400 men for the aircrews...
Less than motorised division... And all aircrews will fly in its group planes

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...ok and what do you think how many ground-crews you will need for refueling, repairing, reloading 1200 planes ?
Lets say 90.000 men for all the things you've mentioned and not

. Most of the ground crew will fly in the bombers. All other will use transport planes.
...AFAIK an averager STR bomber has 4t payload: means you have to bring in 4800 tons of bombs for one attack ~ at least 120 trucks ...
On typical missions the load was 4000-5000 pounds over operating ranges of 1400 miles. Its B-17. But OK. Lets say 120 trucks. Typical german armored division has more than 2000 of trucks

. Looks like the whole 8th Air Force will be supplied by trucks, requisited from a medium transport company

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...and don't forget the truck for the fuel !
Sure

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and in HOI you can even make a quick rebase stop in the middle of nowhere !
This is not good

. But possible for small units.