Well seeing as this thread was already discussing aircraft as rare in the field as the Ki-67, the Ju 388, and the Arado 234 then I think it's Ok to include an aircraft as important as the Mosquito. Even with two squadrons, it made a mark, and was noticed, fortunately. It's importance only grew as we know very well.
Perhaps I wasn't clear in my post. The Mosquito, important as it was from 1943 on as a bomber had very little impact in 1942 so claiming it was the best medium bomber in th e1939-42 time period is debatable. The opening post makes no time distinction, that came later. The Ki-67, the Ju 388, and the Arado 234 have got nothing to do with 1939-1942 either although they do come into play for the 2nd half of the war.
My criteria for a light bomber is (somewhat arbitrarily) something that carries about the same amount of bombs as a fighter bomber to a range not much greater than a fighter bomber can fly. These are kind of useless unless they are super accurate or deadly (i.e. dive bombers or torpedo bombers) or have a good survival rate, though with a navigator they could also be useful as pathfinders. A medium bomber is a plane that can carry more than a typical fighter bomber (often about 2,000 lbs) and carry it a bit further than most fighter bombers can fly (say close to 1,000 miles nominal range). A heavy bomber is something that carries a lot of bombs a very long distance (say closer to 2,000 miles) - to me there's only a few of those: B-29, Lancaster, B-17, B-24, Hallifax etc.
Your criteria is somewhat arbitrary and also needs the use of the retrospectroscope. Plenty of air forces had light bombers in the 1930s and into the first years of WW II. They carried, at the time, a lot more bombs than a fighter bomber because fighter bombers either didn't exist or carried truly small payloads. Comparing 1942-44 fighter bombers to 1938-1941 light bombers skews things somewhat.
Same with medium bombers. in 1938-41/42 they carried a lot more bombs than the fighter bombers of the time (again non extant or only in small numbers with small bombs) and carried it an awful lot further, not bit further. There were very few fighters that could fly even 600 miles without any bombs in 1938-41. 1942 saw a few show up.
Heavy bombers, a bit more of the same, applying 1942-45 standards to 1939-42 skews things.
My criteria for what makes a good bomber is different from most. Most people seem to believe whichever bomber could carry the heaviest load of TNT to the target area and drop it somewhere in the vicinity was the best. To me what makes a good bomber is destroying their target at a fairly high rate, i.e. not 1 or 2% of the time but 30 or 40% of the time (per raid, lets say). And mostly returning to base intact, as in, the majority of the squadron makes it back.
Carrying the heaviest load of TNT to the target (and returning) is a
good starting point for evaluating bombers. It is not the total evaluation.
However if you need 100 bombers of one type to get the target effect of 50 of another type then things do need to be looked at. the 50 larger, more expensive bombers may be a better deal than 100 cheap, small bombers.
A lot is made of bomber A having destroyed a certain target on a one day mission to prove how good the airplane was. Rather overlooks the crew. Some crews accomplished quite a bit with some mediocre (if not down right poor) aircraft.
The Russians actually got this contraption to work a few times.
from Wiki,
. On 1 August 1941, a pair of TB-3s in
Zveno-SPB configuration, each with two
Polikarpov I-16 fighters carrying a pair of 250 kilograms (550 lb) bombs, destroyed an oil depot with no losses in the port of
Constanța,
Romania.
[11] On 11 and 13 August 1941,
Zveno-SPB successfully damaged the
King Carol I Bridge over the
Danube in Romania."
However the training and rarity of the crews that could successfully use this combination kept it from becoming more common.
Aircrew training, equipement and doctrine have a lot to do with the success or failure of number of different types of bombers.
British had poor training, not very good bomb sights, poor navigation, poor bombs and not very good doctrine at the beginning of the war. Expecting much more than the air crew to die bravely was not realistic. does that mean the aircraft themselves (and their engines) were at fault?
BTW the standard British 500lb bomb at the beginning of the war held about 65kg of TNT so try to compare that to the Soviet 250KG bombs for bridge busting.
A large bomb load gives options. A small load restricts options. Options include trading bomb load for range and options in types and sizes of bombs for different targets.
Some bombers had rather tight bomb bays and despite carrying a decent weight options were restricted, but in general bomb load is a good indicator of flexibility.
British did some bombing raids that promised little hope of success, like the first operational use of the Manchester. Night of Feb 24/25 1941 they attacked the Hipper in Brest with light loads of 500lb SAP bombs (as used on the Skua). Trouble is the 500lb SAP bomb had little hope of penetrating the armoured deck/s of the Hipper.
The Manchester was pretty much a disaster as a bomber for a number of reasons but the failure of this raid had little to do with the Manchester itself.
BTW the Japanese build hundreds of these things.
because the fighter bomber of the time was this.
max bomb load 100kg. (four 25kg bombs) range 390 miles without drop tanks or bombs.
