I've done some more research on Luftwaffe bombers and bases in 1938, and I was able to dig up some information on the endurance of some of the early model He 111s, and the Ju 86.
I learned that even the early Ju 86s couldn't reach England from Germany. Although they had decent endurance (due to their diesel engines) their cruise speed was pathetically slow.
The first He 111 with sufficient endurance to bomb London from Lower Saxony was the He 111E-3, of which 67 were produced (
source). It had a loaded cruise speed of 235 mph, and a top speed of 265 mph (
source). (I discovered that the reason many later models had such low fully loaded speeds is that they had external bomb racks.) However, a Gladiator squadron vectored into position by radar could still have caused serious damage to a
Gruppe of He 111Es, and a Hurricane squadron would have massacred them.
The He 111E-4, of which only 10 were built, featured the aforementioned external bomb racks, and may have included a 220 gallon auxiliary fuel tank in the bomb bay. The E-5, of which "few" were built (sources differ), included both the bomb racks and the bomb bay tank.
The He 111F-2, of which 20 were built, was similar to the E-3. The F-4, of which 40 were built, was similar to the E-5 (
source). If our Czech source is accurate, only about 10 of these would have been delivered at the time of Munich. But I'll grant for the sake of argument that there were enough longer-range variants available to equip one
Gruppe.
The He 111J had originally been designed as a torpedo bomber for the Kriegsmarine. But after 10 pre-production J-0s were built, the last 80 J-1s were completed with bomb bays, and were thus similar to the E-3 (
source).
The upshot of all this is that the Luftwaffe had fewer than 200 bombers capable of reaching London from Lower Saxony, including up to 30 longer-range models.
According to a source to which I can't link
*, the He 111E-3 had an endurance of 225 minutes at cruise speed. Multiplying that by the loaded cruise speed of 235 mph and dividing by 60 gives 880 miles. Some range will be gained by the small speed increase after the bombs are dropped, and by carrying a reduced bomb load, but, as discussed, fuel must also be allowed for engine warm-up, take-off, forming up, climbing, and waiting to land, plus the inefficiency of flying in formation. And of course a reserve for combat and other contingencies such as navigation errors and bad weather is highly desirable. But we can go with the 400 miles that Henri's source suggested, even though that might be a bit optimistic for all but the smallest raids.
I found two suitable Luftwaffe bases that were available in 1938 and are within 400 miles of London, assuming that flying over France and/or neutrals is not allowed. One is Jever, near Willhelmshaven, which is still a Luftwaffe base today (ICAO: ETNJ), and the other is Varel, about 10 miles south of Willhelmshaven, which was mostly demolished after the war. Additionally, the
Gruppe equipped with the longer-range He 111s could have been based at Oldenburg, which is about 30 miles south of Jever. So this means that about 90 bombers could have been based within range of London. (FWIW, Jever and Varel are also within 400 miles of Sheffield, Leeds, and Newcastle-upon-Tyne.) And don't forget that the British would have had over 100 Whitleys available, which could carry three times the reduced bomb load of the He 111, and easily reach most German cities, including Berlin.
However, it does not mean that the Luftwaffe could have launched a 90-plane raid against London every day. Recall that I mentioned earlier that in August 1938 only about half of their bombers were in commission, and only about half the number of crews required were available, of which the majority weren't fully trained. Although, as discussed, the Luftwaffe was able to raise the in-commission rate substantially during September by severely curtailing flying hours, that undoubtedly didn't help the training situation.
The wear-and-tear on the aircraft, and the strain on the crews, from continually flying long-range combat missions would have caused the in-commission rate to plummet, and operational losses to mount. So I imagine that the three
Gruppen would have been lucky to put up half of their aircraft every day, or maybe a 75% maximum effort once a week or so. And this is before considering enemy action.
I've already discussed the He 111's weak defensive armament. On top of that, unlike their 1940 descendants, these models lacked cockpit armor and self-sealing fuel tanks. In addition to making them easier to shoot down, this means that even a minor fuel tank hit, whether from fighter or flak, would almost certainly have resulted in the loss of the aircraft, and probably the crew as well, due to fuel exhaustion before they could return to Lower Saxony.
Presumably after one or two of the aforementioned Hurricane massacres, the Luftwaffe would have switched to night bombing. But we have to keep in mind that, as has been mentioned, they didn't have Knickebein at the time, so bombing anything other than London would have been problematic, and even London wouldn't have been a sure thing.
Optimistically, the Luftwaffe could probably have dropped about 50 tons of bombs on London every night. However, as I've mentioned, 24,000 tons of bombs were dropped on the city during the Blitz, sometimes by raids involving hundreds of aircraft with much larger bomb loads. And this happened at a time when Britain stood alone against Germany, which would not have been the case in 1938. Yet Britain didn't sue for peace.
So Henri, in view of the above, please explain exactly how the Luftwaffe could have bombed Britain into submission in a week in October 1938.
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*I got it from a closed Io group run by J.D. Webster, designer of air war games and former US Navy A-7 pilot. If anyone really wants to see it PM me and I'll either send you the PDFs or show you how to join the group.
