I'm writing an essay about the Bombing of Auschwitz for a third year Holocaust course (I'm graduating this year), and I have had some experience about this debate but I'm a bit stuck on the actual planes that were used and some terminology.
First and foremost, what is the 'range' of a plane. I've been researching allied heavy bombers and most of them seem to be in range of Auschwitz from the Foggia airbase which would have been used in the event of this bombing campaign. However, they aren't mentioned in most of the debate on the subject. The airbase was 1000km away from Auschwitz which would make it a 2000km round trip. The B-24, B-17, B-32 and the Lancaster to name a few all had longer ranges than this. So were there other factors that would drain fuel, like flying over the Alps? Or taking a High-Low-High approach which might maximize accuracy?
How much did the weight of bombs affect the range of aircraft? Are the statistics regarding the range usually including the weight of bombs, or are they just the maximum flight range with no other factors? Would they ever have been flown to their maximum range or are these just theoretical and they stayed within a comfortable point of no return?
I'm trying to not reach any conclusions about my paper until I've done research, but I'm trying to stay away from the morality argument that many historians tend to fall into (David Wyman, Martin Gilbert etc.) and instead focus on the actual logistics of a potential bombing campaign (so the bombers, strategic bombing accuracy reports, the actual intelligence about Auschwitz available to the allies).
If anyone has any good book recommendations, I'd appreciate it as well. I'm using the British and American Strategic Bombing Surveys, Aircraft of the Royal Air Force since 1918 and other books centered on this debate
If you are going to discuss attacking rail lines, you will want to reference Engines of War by Christian Wolmar. In it, he details the resilience of the German rail network in WWII. Most attacks on rail lines resulted in at most a temporary interruption in rail traffic, generally lasting less than 24 hours. As you know from the Strategic Bombing Surveys, the ability to hit anything smaller than a city was quite rare. The only substantial damage to the German rail network's ability to function came late in the war with the "tallboy" bombs that could destroy railroad viaducts. Other than those attacks, hitting a rail line could be repaired with dirt, rocks, railroad ties, rails, and untrained labor. Wolmar cites British analysis of the German rail network, which points to the only weakness in the German system being a paucity of triangular junctions.
As for the operational details of the planes involved, you would likely want to reference Jane's. I believe it would have the numbers for range with a bomb load that you are looking for. Alternatively, you could find some of the longer missions undertaken and find the bomb loads for those missions, then do some map work to see if those same missions could have hit the targets you're examining. Planes always operated with a certain amount of reserve fuel, though. There was too much risk to operate at the extreme theoretical maximum range--with the notable exception of the Doolittle Raid.
You may also want to hit up Martin Van Creveld's Age of Airpower. He has a brief look at using bombers to stop the Holocaust. He goes into more depth on strategic bombing overall, and his bibliography may be of some use to you.
Things to consider:
Late in the war, when bombing the camps was a relevant idea, the bombing offensive was in full swing. Any attempts to divert bombers from their priority mission were met my fierce resistance. Bombing camps wasn't the only sort of diversion that various interests had in mind- there were also requests to use bombers to help the Warsaw Uprising, several assassination plots, etc. There was even lots of grumbling when the American 8th air force was given tactical targets in Northern France before the Normandy landings. The bomber offensive, in the mind of its controllers in both Britain and the US, had a clear objective meant to end the war as early as possible, and anything that weakend this served to prolong the war.
Minor point, B32 wasn't developed in time to be used in Europe, and is irrelevant.
The actual range of the bombers is but one of many considerations. Using bombers at the absolute maximum range results in no margin of error, not a good thing in combat when aircraft are being shot at or might experience mechanical problems. That's not even factoring in other limitations such as the range of fighter escorts.
Payload has, and had, a tremendous effect on aircraft range. A fully loaded aircraft can't fly nearly as far as an empty one. Just look at airliners today- there is a reason there are no direct flights between Sydney and Europe, even though many aircraft can easily make the trip empty or with light payloads. As for the range of the World War II bombers, most sources will specify if they're giving the empty range, effective combat range, or otherwise. Effective combat range is shorter than empty range, plus you need to factor in the round-trip. For example, the Hamlyn Concise Guide to American Aircraft of World War II gives the range of the B-17 as 2000 miles with a 6000 lb bombload. Let me know if you have trouble finding others you're interested, and I'll put up what I can find.
With piston-engined aircraft, unlike jets and turboprops, altitude doesn't make a trip much more fuel efficient. It is much more time efficient to go as high as you can (faster true airspeeds at high altitude), and it is usually safer to go high in a combat environment, but it doesn't save much fuel or give you much more range.
Precision bombing in World War 2 was anything but. I think many people take this the wrong way and assume that targets were usually undamaged- it was certainly possible to hit a specific plant hard by late in the war, but lots of other things nearby would be hit as well. It's just a limit of the technology- without radar-assisted ground-speed and wind-drift detection, the bombsights were only as good as the values fed into them, which could be very difficult to get accurately. In fact, the Royal Air Force kept using a derivative of the Blackett sight well into the 1960's- it was the development of radar, laser, and inertial guidance that made today's "smart" or precision bombing possible, not better bombsights.
The above fact, combined with the fact that very little of the area of a concentration camp would be an effective target, makes hitting a gas chamber or crematorium from a standard 18000 foot bombing raid a very difficult task. Some sort of low-level tactical raid would have been better, such as British raids on Gestapo targets in Operations Jericho and Carthage, would have been better, and I would guess that getting such aircraft into Poland would be difficult. Plus, even if you did hit the target, I think it would be possible to repair. Look at the analaysis of the bombing of the Luna (?) refinery in the Strategic Bombing Survey- that plant needed dozens raids over the timespan of a few months to put it out of action. One raid would not have had much appreciable impact, you would have needed a sustained attack on the camp, making the operation even more dangerous and less cost-effective.
As a minor digression for the railway argument, Mierzejewski's "The Collapse of the German War Economy" is great for this. I don't know how well that relates to your topic, but it gives a good overview of what was needed for strategic bombing to be actually succesful (correct target selection, sustained + unrelenting attack on those targets)
Or taking a High-Low-High approach which might maximize accuracy?
This was very rarely done with the long range bombers you mentioned. This was for several reasons. First descending and then climbing back up costs time and fuel. Second, AA guns have much great accuracy shooting at low flying aircraft. Third, it leaves the formations open and vulnerable to fighters. For example a B17 has a service ceiling over 30k, but are relatively slow. To decent for a bomb run would usually be foolish as fighters could scramble and engage the bombers quickly. As opposed to scrambling fighters then climbing to 30k feet which would take a while.
With all those disadvantages it did happen several times. See below for the details of Operation Tidal Wave. In this raid the Allied 15th Airforce lost around 1/3 of its bomber force.