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hitman

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Everything posted by hitman

  1. Lets try this one more time. This - is what is currently modelled. The DCS P-51 is NOT aircraft 44-15342. The light green line represents the DCS P-51 very closely to performance with regards to this chart.
  2. Been reading charts like this since A&P school, and it says 435kts @ 26k. Now at around 24,500 to 25k, it does intersect 440kts before it loses power sharply. I think you are looking at the chart for the -15NA. Specifically, this aircraft. http://www.wwiiaircraftperformance.org/mustang/p51d-15342.html
  3. Just to throw this out there, this chart states even at 67" @ 26k, should be around 435. Its still fairly close to your tests...maybe the MAP gauge is reading incorrectly at altitude?
  4. http://www.spitfireperformance.com/mustang/mustangtest.html According to these charts here, at those altitudes, these blowers only produce 60.5" @ 1260bhp. I just tested this myself, wasnt able to exceed 60.5, which is per spec on this data.
  5. Out of curiosity, what blowers were on? Were they high or low?
  6. What does the throttle control? Because it doesnt control propeller rpm. It carries a Hamilton Standard variable pitch propeller, which adjusts the pitch via a hydromatic piston that pushes the nose of the propeller forward or aft, which rotates the propellers on a geared transmission connected to the crankshaft. The rpm control controls propeller rpm. The throttle controls engine rpm. In lieu of engine rpm, you have MAP, which is just another instrument, but a more important instrument than engine rpm. All of this translates to which transfers how much power to what. At full throttle, the engine will produce 1400bhp. Adjusting the propeller rpm tells you how much of that power it transfers into the blades to bite the air. At 3000rpm, you are losing hp and efficiency because the propeller tips are spinning faster than the speed of sound...which is amplified at higher altitudes. The speed of sound at 26k isnt the same speed of sound at sea level. Which is why I said 3000rpm at 26k isnt 3000rpm at sea level. What I am getting at is that you probably arent putting a big enough load on the engine, maximizing the amount of horse power to transfer to the propellers. You can do that by adjusting the pitch of the propellers (or you can call it adjusting propeller rpm, same thing) to a lower engine rpm. Anytime you put a load on the engine, you will see a drop of MAP.
  7. Constant speed prop means that it stays set at the prop speed you set it at when you adjust idle. For example - increasing the throttle and engine rpm will not change the propeller speed, the speed stays constant. Adjusting the pitch on the propeller blade causes the angle of the propeller to flatten against wind resistance, which increases the load on the propeller, which increases the load on the engine, which will decrease both engine rpm AND blade rpm. All changing pitch of the propeller does is increase the load on the engine. At full forward, the load on the propeller is minimized. At full back, its maximized. The throttle controls engine rpm. The prop pitch controls prop rpm AND engine rpm.
  8. ....its not going to constantly stay at 3000rpm. Its going to stay at the rpm you adjust it to. Its only constant as it will stay at 3000rpm if you back off the throttle. It will also stay at 2700rpm if you back off the throttle. Adjust the pitch for optimum performance, dont know how much clearer I can make it.
  9. Yeah, but dont expect to stay on a moving ship.
  10. P for prop, and thats how the rpm is controlled. 3000rpm at sea level is not 3000rpm at 26k feet. Try trimming the rpm between 2800 - 2900 and test the results. Not going to guarantee you are going to see what you want, but it is a variable you want to explore.
  11. I just assumed it would be like that, unfortunately. I said that simply because its impossible to land on a moving ship and stay on it without being slid off.
  12. Its a hydromatic pitch control, and its located right next to the throttle. Its the black knob labeled propeller outboard the throttle. It should be full forward during takeoff, and at 2700 rpm at landing. The rest is just trim adjustments. I would assign that lever to an axis on your joystick. The pitch controls the rpm by increasing the angle of attack of the blades, which causes drag, which in turn will increase the load on the engine. You will see a manifold pressure drop proportionate to your propeller speed. So dont go overboard with it, because you can come close to feathering the props. Im not sure if they are full feathering, but the blade angle gets pretty steep on them blades.
  13. And in lieu of rocket pods, a bow with arrows equipped with...stuff...
  14. Its a variable pitch propeller, a Hamilton Standard. If anything, it has reduction gears as well to slow the prop down.
  15. Just for sh1ts and giggles, what does the performance scales state that the manifold pressure should be at those altitudes? Max speed at 26k was 437kts, and anything higher in altitude than that you start to lose bhp to the prop. Not just loss in manifold pressure, but airflow over the props. The faster a prop spins, the less efficient it is. Air friction is inversely proportionate to altitude, and the prop would spin a little faster than it should. Perhaps you should increase the blade angle as well?
  16. A ship, yes. A moving ship? Most likely no.
  17. Try a cold day, but try to keep it above -30c at altitude. Anything lower than that is taking a big chance the fuel to freeze, and Im not even sure if thats modelled. Play a little with the carb heat as well. Dont keep it on, just keep it on for a few seconds to melt any ice in the intake and close it to see if any MAP is gained.
  18. Just cuz shameless plug - pY9DQDjsH7w
  19. Well, dont expect to match the AI pilot in performance, if that is what you are ultimately trying to do. Almost all pilots have flaws in the way they handle their aircraft, but the AI handles their aircraft beyond perfectly. Personally, I think you should feel lucky to even get your aircraft that fast at those altitudes. Chances are also good that its the cold altitude that is restricting the flow into your manifold, with ice buildup choking the carb. What is the humidity? Altitude density? Dew point? Is the area you are flying in currently a low or a high pressure area? What about ambient air temperatures? All of these have a dramatic effect on carb performance, especially at altitude. You will see the best performance out of cold, dry air than you will any other type of atmospheric condition.
  20. Did you try retarding the throttle before you hit it? I never use it, perhaps you have to advance the throttle to get emergency power...
  21. Try emergency power? Press e to break the wires on the throttle.
  22. Critical altitude for ram air is different from critical altitude for the supercharger. Its the supercharger that causes the upper manifold pressure to skyrocket like that. I am a bit confused though, the critical altitude for a supercharged engine like the merlin is about 26k, so it should read 14psi or 1 bar.
  23. Good idea. When that happens, get the 780ti during a discount at microcenter. I may or may not do this, providing how good / expensive they are.
  24. Im stuck at the part where you arm the rockets by pressing the PUS. With the virtual copilot in control of the aircraft, the aircraft is at idle, and the generators are off-line, and cannot complete the task. Edit - further testing, I cant even turn the weapons on in any mission... Further edit - testing in a cold start, not even the autopilot system engages, and the weapons panel remains dead cold. Have any procedures been changed for startup? track file included now...how did this end up a double thread? startup mi8.trk
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