Wi naca modified p-38 page 95 alternate history discussion z gas cd juarez

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Click to expand…It was a mind-boggling amount of research and work and still far from perfect but as with everything else in this Timeline, I’m settling for good enough. There are still many more refinements I could make to the math to improve its accuracy such as improving the power curves, refining the mixture settings, and including the transformations needed to better account for changes in enthalpy, exhaust temperature, and gas constants. However, I am neither an engineer nor physicist, so I think my approximations derived from available data are adequate g gas lol.

What I found most interesting is the amount of potential power for the blowdown turbine, especially with water-methanol injection. I played around with the v gas station numbers some and was able to peak it at nearly 900 HP before losses at critical altitude for 100Hg. After losses it works out to almost 740 HP delivered back to the crank for a Net Brake Horsepower of 3719 HP and final 25% improvement in NTHP (3162 NTHP) and 20% reduction in NTSFC! When adjusting for dynamic propeller efficiency using the Aeroprop from the P-38K this works out to a NTHP of 3103 HP with flying at 400mph at 15,200 feet, or 2906 HP at 500mph (whether or not the airplane will be capable of that is another matter).

I have more work to build the power charts for the ATL G-Series engine and adjust the turbines (supercharger, blowdown, and turbocharger) to best fit the new engine but all of that will come sometime in 1945/46, I think. Whether we go the route of driving the S/C off the Blowdown or not remains to be seen. There are definite gains available by doing so but I fear the added complexity of gearing system may undermine it. Of course, going from two gearboxes (S/C and Turbo-Compound) to one (S/C + T-C) has its own benefits.

There is also the possibility 4 gas planets of going the same route as Wright and having each bank of 6 cylinders turn its own PRT as I had originally intended. Benefits could be found in temperature control (fewer impulses per engine cycle on each turbine) and in using lighter turbine wheels to permit higher RPMs. Again, a downside would be in the system complexity–just look at the experience with the R-3350 IOTL.

Service-worthy engines (V-1710 aboard the P-38, R-2800 on P-47, R-1830 on P-43 and B-24, etc.) used turbo-supercharger (indeed, we can call it turbochager, or turbo as well) as an add-on to the integral supercharger each engine was already equipped with. Job of the turbo was to compress electricity physics test the air once, and then deliver it to the integral supercharger, that will obviously compress it once more. We talk about two stages of supercharging here, and each pressure ratio (pressure after the supercharger / pressure before supercharger ) is multiplied with another. Say, turbo is providing pressure ratio of 3:1, and integral S/C is is providing pressure ratio of 2:1 = total pressure ratio 3 main gas laws of 6:1 (minus the losses, of course). Such a high pressure ratio was instrumental in making possible for, say, V-1710, to make 1600 HP even above 25000 ft. Or the latest R-2800 to do 2800 HP at 30000 ft.

Both supercharger stages need some energy input in order to do their job. Turbo uses/used exhaust gasses, that is basically ‘free’. Engine-stage supercharger, or integral supercharger, used engine power to spin the impeller. The power required was, at P-38, some 200 HP (depending on version) when the engine-stage S/C was delivering 12000 lbs/hr worth of air (= engine is in high power setting). We can note that turbo-compound V-1710 were using a 2-stage supercharger where both stages were engine-driven – the big 12in impeller used up to 450 HP in order to provide the same 12000 gas x reviews ratings lbs/hr of air! So, ‘deleting’ the supercharger(s) from engine all-together, and having the turbine driving both stages ‘frees up’ up to 650 HP (in ideal case) from the said V-1710 turbocompound.

Click to expand…Plus, think of a B-36 Bomber Group and a their P-81 escort Group sharing a base with most of the powertrain shared between them. The V-3420s could even use the same leading edge radiators and intercoolers (etc.) as the V-1710s, just two per engine instead gas prices going up 2016 of one (one per V basically). This may not be as far-fetched as it seems since Vultee and Consolidated have merged into Convair allowing an easy path of common development. Logistics would be easy and in a combat area where resources may be limited you could cross-cannibalize parts between the types to keep as many airworthy as possible.

Another consideration for the V-1710G-TC that has been rolling around in my mind but for which I haven’t yet decided on a solution is the requirement for the engines to turn opposite directions. There are two options to consider, as I see it: they can make two different Compound sections, one right-turning, one left, to match the engine rotation; or, they can use the same compound section but have the Left-Turning one use a reversing gear on the gearbox. The latter is by far the types of electricity pdf simpler of the two but will cost some additional frictional loss and efficiency (and thus return slightly less power) while adding a bit of weight. The former requires alternate production with mirrored turbine assemblies but will (should, anyway) suffer no additional losses in use.

As for the next chapter in the TL, I was originally going to write an alternate version of a 91st Bomb Group raid from Aug. 16th, 1944 gas leak but decided to skip it. The situation in the air has changed enough now ITTL where the specific raid in question likely never happened, or at least not on the same day and under the same circumstances as the OTL raid. In fact, I had even set up expectation for the raid in the chapter Bounced! (when the 82nd FG was surprised in Italy on 9/2/1943) by using the same writing style as I intended to use for this. The OTL story of the raid can be found on the 91st Bomb Group website, in the web-book Mary Ruth Memories of Mobile…We Still Remember by Lowell Getz, Chapter 7: 40 Seconds Over Eisenach, if you care to read it (I highly recommend it). It details the destruction, in heartbreaking detail, of most of the planes flying in the High position with the 324th Squadron to a sudden fighter attack after the escorts (P-51s) were 10 minutes late. ITTL I had planned to replace the escorts with P-38s, which would arrive on-time electricity usage in the us thanks to their quicker initial climb over the channel and higher cruise.

Instead, I’m skipping ahead to the PTO in October. It will only take small butterflies from OTL to get the planes where and when I want them but it may take something far more clever to develop the change as I would like since it requires certain people changing their behaviors and decisions. As part of this, we will see some long range patrol and ground support missions from units of the 5th AF as well as our first glimpse of the purpose built P-38M two-seat NF variant with the 10cm SCR-720A radar (P-38L are earlier P-38H NF conversions, P-38N are P-38J electricity trading strategies NF conversions, both with the AN/APS-6 3cm radar pod, there will also soon be a P-38Q which will be the two-seat variants with the upgraded J powertrain).