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Shortround6. In regards to B-17F service ceiling. You would have to admit that 9000m/30,000ft is a plausible attack altitude for a B-17F whose target is 500km/306 miles from the English coast.
10,000m/33,000ft is stretching it a bit but note that at a fuel consumption of about 1440bs/hour that less than 3600lbs is needed for the round trip after having achieved altitude over Britain and such a "B-17F" would be stripped of a moderate amount of weight, such as the waist gunners and the nose guns bar one 30 Caliber.
The Luftwaffe would be hard pressed to intercept in 1942 or even 1944. Ju 88R with their BMW 801 converted to run of Nitrous Oxide kits developed for the Ju 88S1 in the latter half of 1942 or Me 109 without radar but directed by Wurzbug radar. Both have severe operation limits.
The USAAF did have a escort fighter. It was called the P-38 and although it exhibited problems these were resolved. It at least shows a commitment to the escort fighter and the appreciation of its need even if the implementation was somewhat protracted.
The USAAF did have a escort fighter. It was called the P-38 and although it exhibited problems these were resolved. It at least shows a commitment to the escort fighter and the appreciation of its need even if the implementation was somewhat protracted.
There were three main problems with trying to operate B-17s at altitudes of 30,000ft and above and I am using the 30,000ft as a general benchmark, not something from official paper work.
There is a pilots manual for the B-17F available in the manuals section with lots of pages of charts.
A B-17F at 'basic' weight went 41,300lbs this included 9 man crew, 9 .50 cal guns (only one in the nose, none in radio compartment) 3500rounds of ammo, 900lbs of Misc. equipement, 144 gallons of oil and 1500lbs for the outer wing tanks.
6000lbs of bombs (pretty much internal max, the higher internal loads listed require 1600lb AP bombs of which only a few hundred were dropped in Europe, 7in steel Armour roofs being rather scarce. ) and 1728 gallons of fuel push the weight to 57,700lbs.
Manual shows weights and ranges for a variety of loads including a pair of 4000lbs external.
Charts vary on how much fuel was required for warm-up and take off from 132 gallons to 182 gallons???
there is another chart showing horizontal distance traveled and fuel used to climb to altitude at 5 different weights. at 55,000lbs it takes 150 miles and about 320 gallons to reach 30,000ft. There is a bit of cross over between the charts as the warm up and take off charts allow for climb out to 5000ft while the climb chart is from sea level.
There are 'tactical' range charts but they are calculated and assume the aircraft has been magically elevated to the desired altitude with warm engines/oil and there are no headwinds.
All of these charts or for a single airplane and not a formation. The larger the formation the more allowances that have to be made.
the 2nd point was that the airplane and crew simply could not operate at the higher altitudes as originally intended due to the temperatures. Temperatures from a chart in a different book (in Fahrenheit) are 20,000ft -12, 25,000ft -30, 30,000ft -48, 35,000ft -66.
This is for a 59 degree day at sea level, decimals rounded off. Guns, radios, instruments,etc. froze and did not operate, windows frosted over, cabin heaters and even electric crew suits didn't keep up with temperature drop and so on.
3rd was they found out pretty quick that bombing from 30,000ft wasn't anywhere near as accurate as they hoped. This was one of the main reasons which they canceled all the high altitude medium bomber projects.
the 2nd point was that the airplane and crew simply could not operate at the higher altitudes as originally intended due to the temperatures. Temperatures from a chart in a different book (in Fahrenheit) are 20,000ft -12, 25,000ft -30, 30,000ft -48, 35,000ft -66.
This is for a 59 degree day at sea level, decimals rounded off. Guns, radios, instruments,etc. froze and did not operate, windows frosted over, cabin heaters and even electric crew suits didn't keep up with temperature drop and so on.
3rd was they found out pretty quick that bombing from 30,000ft wasn't anywhere near as accurate as they hoped. This was one of the main reasons which they canceled all the high altitude medium bomber projects.
Also why hadnt this been found during tests in the US surely the temperature over a US bombing range at 30,000ft is roughly the same as over France.
A lot of interesting information.
My point was that it takes only 3600lbs of fuel to to a round trip of 1000km/612 miles at around 30,000ft. IE 300 miles to target plus 300 miles back. You can take of with a full load of fuel 20,000lbs, it doesn't matter, burn however much it off to get to 25,000ft and in the lightened state climb the additional 5000ft or more to get to 30,000ft plus. Then you start your mission to target. You'll even have 60 miles of gliding ability to count into the reserve for the return.
Surely getting rid of the waist gunners helps keep the cabin warm.
As far as accuracy goes. Radar bombing whether it was x-garaet or Oboe or Gee-H or Micro-H all gave an actual true speed over ground that allowed headwinds to be calculated and entered into the bomb fall calculation. The side ways crabbing I imagine was easy to calculate on x-garaet to give a cross wind and maybe Oboe as well. The main trick of the Norden was to calculate the wind drift of the bomber. If the electronics gives it to you all the better.
What wind value do you set on your sight
I would say in defence of the US planners (and it is a very poor defence) that many other nations did the same sort of thing/s although perhaps to a lesser extent.
The German night fighter crews tended to aim at an area between engine and fuselage which would tend to set the tanks alight. I read one night fighter pilots say they did this to give the bomber crew a chance to get out because the crew themselves weren't subject to direct attack. I would say not firing into the bomb bay was also a motivation? Surely the night fighter feared detonating the bombers load. Nevertheless this method of attack would have produced survivors and evidence on many occasion.
Can you clarify what you mean by "not trained or equipped for high altitude work"?Yes and no. The RAF tried high-altitude daylight precision bombing with Fortess I's (B-17C) in early 1941. These raids were carried out unescorted at 30,000ft, and were disastrous - not just because of combat losses, but because the aircraft really weren't up to the task and the crews were not trained or equipped for high-altitude work.
The B-17E and F were way better armed than the -C. That said, they still weren't adequate for self defending operation.Ironically, the USAAF had told the British that the B-17C was not sufficiently well-armed for unescorted bombing over Europe, and they were dead right. When the B-17E and -F came along, the USAAF promptly ignored it's own advice in 1942 and Schweinfurt ensued.
Holy cow, I thought we'd have lost more...On the Army Air Force site it says the USAAF lost 5,548 heavy bombers. . . their losses were actually quite lower than the RAF night bombers, which was 10,000 night bombers lost.
Do you have anymore on that?Switzerland had dozens of Allied heavy bombers parked on airfields by the end of the war. Some of them landed on purpose to opt out of the war.
Which means that GEE, or Oboe should have been used most of the time with H2S used in the proximity of the target to make sure they're where the radio navigation aid says they should be before they continue to release ordinance?H2S and Monica radars were not critical to finding the targets, and in the case of H2S it was manifestly mis-used.
Was this because they were concerned with a malfunction or spoofing?However, it was felt by the brass in England that the bombers needed the ability to guide themselves onto the target
The description, I'm not sure I mentally wrap my head around that... are you talking about each transmitter producing a ripple of energy and the intersection between the two ripples being the correct flight path? Or are you describing something else, and are there drawings one can find online?"Oboe used two stations at different and well-separated locations in England to transmit a signal to a Mosquito Pathfinder bomber carrying a radio transponder. The transponder reflected the signals, which were then received by the two stations. The round-trip time of each signal gave the distance to the bomber.
Each Oboe station used the radio ranging to define a circle of specific radius, with the intersection of the two circles pinpointing the target. The Mosquito flew along the circumference of the circle defined by one station, known as the "Cat", and dropped its load (either bombs, or marking flares, depending on the mission) when it reached the intersection with the circle defined by another station, known as "Mouse". There was a network of Oboe stations over southern England, and any of the stations could be operated as a Cat or a Mouse as the need demanded.
So -.- or .-. indicated you were on course, .....- means "drop bombs"?The initial "Mark I" Oboe was derived from Chain Home Low technology, operating at 1.5 meters / 200 MHz. The two stations emitted a series of pulses at a rate of about 133 times per second. The pulse width could be made short or long so that it was received by the aircraft as a Morse code dot or dash. The Cat station sent continuous dots if the aircraft was too close and continuous dashes if the aircraft was too far, and from these the pilot could make the needed course corrections.
Various Morse letters could also be sent, for example to notify the aircraft crew that the Mosquito was within a specific range of the target. The Mouse station sent five dots and a dash to indicate bomb release.
I didn't know GEE-H was a blind-bombing aid, though I knew you could guide 80 aircraft with it.Along with the range restriction, an earlier system called Oboe, had another limitation: it could only really be used by one aircraft at a time. As a result, the British rethought Oboe, and came up with a new scheme named G-H (also given as "GEE-H") based on exactly the same logic, differing only in that the aircraft carried the transmitter and the ground stations were fitted with the transponder. In this manner, it operated in a similar manner to the currently employed civilian DME system, with the aircraft following a DME arc procedure on one set, whilst using another set (tuned to a different transponder as close to 90 degrees apart as geography permits) to determine the point of bomb release.