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2 b-17 questions

Sat Jul 02, 2011 9:02 am

Happy 4th weekend everybody! I have 2 B-17 questions that i'm not too sure of and would like to get people's thoughts. My first question is did Boeing ever try and develope a blinding light system? Such as massive watt lights mounted in a few places to " Blind" fighters making runs on them. I'm not sure how well it would have worked during day light bombings, but i know driving home after work, that sun in my eyes really messes me up. Even with sunglasses. If the tail-gunner had something like this maybe with the correct system and high watts it may have blinded a german pilot for a few seconds and he would have broke off. Thoughts on that?

Second question is about the engine HP for the B-17. Was there no plans to upgrade the 1,000 hp to a larger engine for better performance? My take is that it would have used more fuel, cut the range and maybe they didn't have the time to redesign the engine and wings to make room for a bigger engine? Did they ever try a p and w r2800 in a b-17 and see what the differences was?

Re: 2 b-17 questions

Sat Jul 02, 2011 11:25 am

Developing a 'blinding light' system would have been an Army development project but probably never went beyond "I wonder if..' stage as something like that would cause extreme danger for the rest of the formation and potentially blinding several pilots causing mid airs, particularly if the guy operating the light was hit and thrashing around wagging the light all over etc. etc. The British did install a million CP light in some DB-7 HAVOCS called 'turbine light' but they were strictly anti night fighter applications and had their own issues one of which was, the light would be turned on and an attack made on the German night fighter, then the light would be shut off but take quite a while dimming completely now making the HAVOC a well defined target for other German night fighters., it would compare to turning off a light in a baseball stadium, the globe glowed for several minutes as it dimmed.

One VEGA built B-17 was converted to 4 ALLISONS as the XB-38 (a B-29 was built as the XB-44 using the double ALLISON W-3420 as a 'what if' in case the R-3350 couldn't be tamed, the 3420 was a monster and never panned out, it was tried in the XP-75 too) and performed about on a par with a stock B-17 and the redesign and rework needed to implement the change was too expensive and way too long on lead time, and potentially to prone to damage to the fragile and suceptable coolant systems from flak than a relatively small, and very tough radial engine. (and the airplane suffered a destructive fire if I recall correctly). As long as the combined machines of WRIGHT, BOEING, DOUGLAS, and VEGA kept turning the crank and a B-17 squirted out the end of the line every hour or so, why go to the interruption and cost of redesigning the entire airplane to install a newer engine like the R-2800 that was already in serious demand for about a dozen other in service aircraft? Coupled with the fact that specific fuel burn data on the 1820's was a long known fact, and up engining would lead to extensive flight testing for fuel burn calculations and perhaps more tanks. That coupled with better bombers coming down the pipeline (B-29, B-32) would have made the modification projects counterproductive and overly expensive for modest gains in performance.

Re: 2 b-17 questions

Sat Jul 02, 2011 12:51 pm

The Inspector wrote:Developing a 'blinding light' system would have been an Army development project but probably never went beyond "I wonder if..' stage as something like that would cause extreme danger for the rest of the formation and potentially blinding several pilots causing mid airs, particularly if the guy operating the light was hit and thrashing around wagging the light all over etc. etc. The British did install a million CP light in some DB-7 HAVOCS called 'turbine light' but they were strictly anti night fighter applications and had their own issues one of which was, the light would be turned on and an attack made on the German night fighter, then the light would be shut off but take quite a while dimming completely now making the HAVOC a well defined target for other German night fighters., it would compare to turning off a light in a baseball stadium, the globe glowed for several minutes as it dimmed.

One VEGA built B-17 was converted to 4 ALLISONS as the XB-38 (a B-29 was built as the XB-44 using the double ALLISON W-3420 as a 'what if' in case the R-3350 couldn't be tamed, the 3420 was a monster and never panned out, it was tried in the XP-75 too) and performed about on a par with a stock B-17 and the redesign and rework needed to implement the change was too expensive and way too long on lead time, and potentially to prone to damage to the fragile and suceptable coolant systems from flak than a relatively small, and very tough radial engine. (and the airplane suffered a destructive fire if I recall correctly). As long as the combined machines of WRIGHT, BOEING, DOUGLAS, and VEGA kept turning the crank and a B-17 squirted out the end of the line every hour or so, why go to the interruption and cost of redesigning the entire airplane to install a newer engine like the R-2800 that was already in serious demand for about a dozen other in service aircraft? Coupled with the fact that specific fuel burn data on the 1820's was a long known fact, and up engining would lead to extensive flight testing for fuel burn calculations and perhaps more tanks. That coupled with better bombers coming down the pipeline (B-29, B-32) would have made the modification projects counterproductive and overly expensive for modest gains in performance.


Interesting take on this question. Although I somewhat agree with you on the lighting situation but not fully. Mid air collisions happened anyways from clouds so it's tough to say that this would blind other b-17 pilots as well. Flying in formation was very tough on them but they did fly basically straight and followed their bomb leader. I'd be much more worried about getting hit from .50 cals from other B-17's than a light.

As for upgrading the engines i wouldn't see why it wouldn't be a logical fit for the B-17. Several companies did vast improvements to their planes while on the essembly line so i wouldn't see how it would have hurt the B-17. Pratt and Whitney would have had no problem giving 2800's to Boeing during peak wartime production. Chance-vought, pratt and whitney and hamilton standard. Same combo but they constantly were making changes and having X aircraft to see what would work. The p-51 changed engines and razorback to bubble and so with the P-47. So i'm not seeing how the developmental team would not try all different angles to try out something better for the fort. thanks for your input

Re: 2 b-17 questions

Sat Jul 02, 2011 1:52 pm

Maybe instead of using lights to blind attacking fighters a light system ala Project Yahudi could have been used to make a B-17 disappear. That was sucessfully tested on a TBM and a PB4Y. It would have had limited viability, but it would have been interesting.

Re: 2 b-17 questions

Sat Jul 02, 2011 2:10 pm

Clifford Bossie wrote:Maybe instead of using lights to blind attacking fighters a light system ala Project Yahudi could have been used to make a B-17 disappear. That was sucessfully tested on a TBM and a PB4Y. It would have had limited viability, but it would have been interesting.



IIRC, that project was intended to make a plane vanish from a surface ship or submarine.
I don't know if it would have worked to hide a plane from a rapidly moving (and in 3 axis) aircraft.

Any thoughts on the matter?

Re: 2 b-17 questions

Sat Jul 02, 2011 3:10 pm

didn't they have a program on about that? When the sailors were all cut in half and stuck in structures on the ship when they tried to make the ship reappear

Re: 2 b-17 questions

Sat Jul 02, 2011 3:23 pm

whistlingdeathcorsairs wrote:didn't they have a program on about that? When the sailors were all cut in half and stuck in structures on the ship when they tried to make the ship reappear


Nope, that was just a hollywood movie.

What they are referring to was mounting a bright light to an aircraft that made it difficult to see when it was flying towards a surface ship.

Re: 2 b-17 questions

Sat Jul 02, 2011 4:57 pm

TAdan wrote:
whistlingdeathcorsairs wrote:didn't they have a program on about that? When the sailors were all cut in half and stuck in structures on the ship when they tried to make the ship reappear


Nope, that was just a hollywood movie.

What they are referring to was mounting a bright light to an aircraft that made it difficult to see when it was flying towards a surface ship.


Having seen video of these tests, on a cable network, I was shocked at how well it worked.

Tim

Re: 2 b-17 questions

Sat Jul 02, 2011 9:49 pm

thats why i never understood why it wasn't tried out on a fortress when the losses were so high during day light bombing raids

Re: 2 b-17 questions

Sun Jul 03, 2011 12:01 am

The problem with "lee lights" in the air-to-air application is that the lights are only going to be useful at certain angles. While the Germans preferred head-on attacks, fighter attacks could literally come from anywhere "around the clock" and from any altitude. It would be almost impossible to make a light that could make the plane disappear from any angle and not add so much weight and power draw to make it impractical.

In the anti-ship and anti-sub role, the plane's angle relative to the target was always the same: The plane would have to attack a sub in a frontal attack, thus putting the lee lights on the forward part of the airplane made sense. A plane like an AC-130 would be less practical for that application as that plane relies on orbiting the target versus heading straight towards it.

As far as the B-17 engines, I do believe the later 1820s (I think it was a dash 97) did have a "war emergency power" setting that yielded 1,350 hp. I think the Allison engined XB-38 proved that larger engines weren't going to yield much results, and given the need for B-17s "as is", the engineering redesign was probably not worth it. It seems that the four engine types really weren't messed with much in terms of engines. It wasn't until after the war that operators began "up-engineing", such as putting 2600s on the Privateers or the Super Catalinas

Re: 2 b-17 questions

Sun Jul 03, 2011 5:20 am

funny becuase i would still take b-17 engines instead of b-29 engines anyday :wink:

Re: 2 b-17 questions

Sun Jul 03, 2011 8:14 pm

As for up engining the B-17 I think it was not pursued because the aircraft worked fine as it was. You were not going to get much more performance out of a 17 with bigger engines unless it was an uprated R1820 that could be dropped in with minimal mods. One of the most successful aspects of the US war effort was how designs of all types of weapons were evaluated and then promoted or discarded. It seems to me there was very little politics involved. All anyone cared about was the value of the weapon and the efficiency with which it could be built. With the B-17 doing the job in Europe and the B-24 doing as well or better and the B-29 andB-32 in development there was no need to radically alter the B-17.

Re: 2 b-17 questions

Sun Jul 03, 2011 8:17 pm

1820s would not have gotten the B-29s off the ground. The -97s produced about 1200 hp under normal conditions at sea level. Also remember that the unreliability of the early 3350s was not realized until the B-29 project was too far into the game to change. Besides, they were state of the art at the time. There was no time for growing pains as combat aircraft were needed immediately. It was thought that the streamlining of the Allison installations would gain 20 kts but was negated by the drag created by all the radiator openings in the leading edge. About the only thing that could be done to current flying B-17s is to install the same engines as the S2 tracker, which I believe is the -86. (Someone correct me if I'm wrong). But much like FIFI, with her new engines, they would not bolt right up and fly away. Several QEC design changes would be neccessary as described to me some time ago by Eddie Packard, along with the blessing of the FAA.

Re: 2 b-17 questions

Sun Jul 03, 2011 8:59 pm

John Dupre wrote:As for up engining the B-17 I think it was not pursued because the aircraft worked fine as it was. You were not going to get much more performance out of a 17 with bigger engines unless it was an uprated R1820 that could be dropped in with minimal mods. One of the most successful aspects of the US war effort was how designs of all types of weapons were evaluated and then promoted or discarded. It seems to me there was very little politics involved. All anyone cared about was the value of the weapon and the efficiency with which it could be built. With the B-17 doing the job in Europe and the B-24 doing as well or better and the B-29 andB-32 in development there was no need to radically alter the B-17.


And that was indeed sound judgment. Too often people overlook that World War II was as much a war of production as it was anything else. With over 12,000 B-17s built it was critical to not upset prodution with modifications that were not really needed. In that estimation the B-17 was "good enough" to do the job. Close to 18,000 B-24s, 50,000 Sherman tanks and thousands of ships produced during the conflict, plus the B-29 tested and close to 4,000 built. I forget how many Opel Blitz trucks the German produced in ten years of production, somewhere around 60,000 I believe. In four years the US produced over 500,000 CCKW deuce and halfs and Studebaker built about 200,000 US6 trucks. (We had enough capacity that we could actually afford to wast some on dead end programs like the P-75!) That does not even take into account the T-34 tanks and MiGs, LaGGs and what not produced in the USSR. The Axis was crushed under the weight of Allied industry. The never stood a freaken chance.

Re: 2 b-17 questions

Mon Jul 04, 2011 11:29 am

Clifford Bossie wrote:Too often people overlook that World War II was as much a war of production as it was anything else. <snip> The Axis was crushed under the weight of Allied industry. The never stood a freaken chance.


Quoted for absolute truth. Between the vast production disparity and the focus on key industries (particularly petroleum production and refining), it was never a question of "if" but a question of "when".

Lynn
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