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Everything posted by Nerd1000
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The DCS MiG-21 manual says that typical sea level fuel consumption in full afterburner is 4.2L/s, giving you approximately 11 minutes of low speed flight on internal fuel. Fuel consumption increases to 6.4L/s at Mach 1.06, so that 11 minutes is decreased to something closer to 7 minutes if you go supersonic.
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Running higher octane fuel allows more boost without risking detonation/pre-ignition (also known as 'knocking' or 'pinging'). What'''s detonation/pre-igniton? Prepare for an explanation. When the piston compresses the air/fuel mixture in the cylinder it gets heated: if the gas is heated to a temperature above the autoignition point of the fuel, it will explode. Diesel engines exploit this effect by compressing the air until it is above the autoignition point of diesel fuel and then injecting the fuel into the cylinder. The fuel spontaneously ignites, and drives the piston down on the power stroke. In an Otto cycle engine (such as the engine on the Mustang) the fuel is mixed with the air before it enters the cylinders and ignited by a spark plug. This turns compression heating into a big problem, because if the fuel's octane rating isn't high enough it may reach its autoignition temperature and explode before the spark plug would usually set it off- this is called detonation or pre-ignition (depending on the exact circumstances), and it causes the engine to make a 'ping' or 'bang' noise, which is why it gets called knocking or pinging. The engine then has to fight the pressure of the hot exhaust gas in order to finish the compression stroke and start the power stroke, which wastes power and puts excessive strain on the piston, connecting rod, crankshaft and all the bearings that allow them to move. Now on to the supercharger. The supercharger on your engine is a big air compressor. It compresses incoming air and pumps it into the inlet manifold, which then feeds it into the cylinders (the 'boost' gauge indicates the pressure inside the manifold in inches of mercury). Because the air has already been compressed it is already hot when it goes into the cylinders, which moves everything closer to the autoignition point. Thus, the more boost you have, the higher the octane rating you need. The engine on the Mustang has an intercooler, which cools down the compressed air before it enters the cylinders (the Bf109's MW50 injection does a similar job) but even that isn't enough unless the octane rating of the fuel is high enough for the increased boost.
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The Bf 109 put on a lot of weight going from the F-4 version to the K-4, along with vastly increased power output: up to 1450PS for the F-4, compared to the K-4's 1800-2000PS. Obviously more power means more prop torque. The roll rate pretty much stayed the same, but the plane's turning performance and pleasant handling were reduced. Many RAF pilots also said they preferred the Spitfire Mk V to the much more powerful Mk XIV version. Its a similar situation to the 109: the Spitfire went from around 1300hp in the Mk V (depending on engine version) to around 2000hp in the Mk XIV and put on a heap of weight. The plane didn't fall behind on roll rate, but its other handling characteristics were made worse by the extra weight and power.
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I believe his point is that there is very little functional difference between the guidance systems of SAMs and AAMs. Therefore, if Radar guided SAM systems have been successful in hitting western aircraft, there is no reason that air launched weapons incorporating similar features should be any less effective. In fact (discounting the potential for better ECM resistance in a larger ground based radar) A2A weapons should have a better probability of hitting their target: a SAM has to accelerate from a standstill, so it will always be larger, heavier and less maneuverable than an air to air missile of the same maximum range.
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RL pitot-static systems are not 100% accurate, especially at transonic mach numbers due to weird airflow around the plane. You should re-test at lower speeds (400-600 km/h) and higher speeds (More than Mach 1.2).
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109, issues to address before leaving beta
Nerd1000 replied to ShadowFrost's topic in DCS: Bf 109 K-4 Kurfürst
Haven't got any data on methanol, but 40% ethanol in water will burn nicely. Ever had one of those puddings where they douse it in brandy then light it on fire? -
Su24 low pass over USS Donald Cook (missile destroyer)
Nerd1000 replied to Elwood's topic in Military and Aviation
I think you could set the ship to 'weapons hold'. Then assign a trigger zone on the ship and add a little bit of simple scripting so that to complete the mission the pilot has to fly within a certain distance of the ship below a certain altitude 3-4 times, then RTB. -
I prefer to fly planes that don't resemble swiss cheese, so no.
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At the risk of starting a big argument, the effectiveness of mineshells vs normal HEI rounds is debatable. They have much more explosive (and thus a lot more destructive energy) but the thin drawn body lacks mass to be thrown out as fragments. Shockwaves are generally poor energy carriers compared to fragments, as the shock will lose power much more quickly over distance and cannot penetrate objects like a fragment can, so it's up in the air as to which approach worked better in practice. IMO You'd need statistical data to make a proper judgment. Also, doesn't the MG151 have a higher fire rate than the Hispano? from what I've read the MG151/20 fires 750rpm while the Hispano Mk II fires 600rpm. Obviously the synchronization would slow it down a bit, but Kurfurst has claimed on other forums that the Germans used an electrical synchronization system that allowed very small losses in rate of fire (and he certainly knows more than me about the specifics of WWII German gun installations).
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The radar energy isn't perfectly directed- while most of it goes where the radar is pointed, some escapes out to the sides and rear. As for irradiating the hapless ground crew, take note that the energy emitted by a radar is not ionizing radiation. Generally an aircraft radar emits in the centimetric band, AFAIK usually between 1cm and 10cm wavelength. This is rather similar to the radiation emitted by a microwave oven, which doesn't give you cancer or radiation poisoning. On the other hand, if you were to power up the radar and stand right in the middle of the beam for long enough you might get cooked like last night's leftovers. It could probably also interfere with or damage cardiac pacemakers, putting anyone with one at risk of going into cardiac fibrillation if they walked through the beam.
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109, issues to address before leaving beta
Nerd1000 replied to ShadowFrost's topic in DCS: Bf 109 K-4 Kurfürst
I remember the AB series cluster bombs from Microsoft CFS3. Could never get them to work well (though I was just 12 at the time, and the 109G's FM in that game left a lot to be desired). What kind of bomblets did it carry? -
There is Betty shouting 'Over G! Over G!' at you to give some warning, at least with English avionics.
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at first glance the camera angle makes it look that way, but it is in fact a Dora. You can tell by the circular air intake on the right side of the engine.
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Takeoff with drop tank, climb to altitude, jettison drop tank. You are now high in the air with 100% internal fuel (I am aware that the flanker cannot carry drop tanks, but it is possible for other aircraft).
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Don't let Force Feedback Die!!!
Nerd1000 replied to drsgfire's topic in PC Hardware and Related Software
Helicopters have an option for 'central position trim' or suchlike. When it is on trimming the stick is designed for non FFB sticks (i.e. centering the stick will keep put the in-game controls in the new trimmed position). Try switching it off and see if that helps. -
For me April fools was yesterday (international date line strikes again!). From my perspective you are the fool, fool!:smartass:
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fair point.
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Interesting. I read that the P-51D's wings were thickened to allow the guns to be mounted upright, solving the B/C model's chronic jamming issues. Perhaps the gun jamming problems are also a bit of a myth?
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That looks like the bastard love-child of a F-5, F-16 and F/A-18.
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The MiG's ailerons have poor authority at high angle of attack. Under those conditions you roll by applying a large amount of rudder in the direction you want to go. Naturally this will tend to bleed your speed pretty badly due to the large slip angle, so don't use it unless you need to.
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The P-51B was actually slightly faster than the D due to its thinner wing and less draggy razorback fuselage, so performance wise it wouldn't make much difference compared to the current mustang assuming that the B/C ran at the same boost pressure. The weakpoint of that design is far inferior vision from the cockpit and only 4 guns in really crappy mountings that made them prone to jamming at inopportune moments (rather like the 109's MK108 :D).
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For comparison, some info on the Mk V's vokes filter can be found here. That site also has some other interesting stuff about operating the Spitfire Mk V in Northern Australia's rather demanding environment.
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How to fire the big anti ship missile?
Nerd1000 replied to fighter1976's topic in DCS: Flaming Cliffs
The Su-27 can't carry an anti-ship missile. -
DCS: F-14A/A+/B by Heatblur Simulations coming to DCS World!
Nerd1000 replied to Cobra847's topic in DCS: F-14A & B
F-14 is quite a long ways off. Get something that's out now, like the MiG-21. And SLI is certainly not necessary. I run the game on a AMD R9 270 and it looks great with 50-60 fps framerates most of the time (it drops down to 20-30 fps over cities or dense forests). -
The pipper will jump all over the sight glass if you've got it set to a very long range in A-A guns mode. In my install the pipper no longer resizes itself when I change the range setting, so if you have the same issue you might not have noticed that the sight is set to 2000m or something.