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Gavrick

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  1. Gavrick

    3.001 aircrafts parameters available

    Here we mentioned the report, which says about the speed of 530 km / h at the ground and 610 at an altitude of 5800 m. Yes, we have this report. However, the notes in this report refer to the unsatisfactory quality of this particular aircraft (problems with cracking of the skin and paint, defects in the sealing of engine cowling are noted). At the same time, the characteristics of seven other serial aircraft significantly differ for the better (although they are not identical to each other). Therefore, in this case, averaging the characteristics, considering a deliberately defective aircraft - will not be a "gold middle". And the average characteristics of serial aircraft are directly given in the report, which I showed above.
  2. Gavrick

    3.001 aircrafts parameters available

    Seven aircraft, from May 1943 to December 1943.
  3. Gavrick

    3.001 aircrafts parameters available

    I'm afraid of upsetting someone, but the serial La-5FN in 1943 really had very good characteristics. Despite the numerous quality problems, it was a good aircraft with a good engine. For confirmation, I quote from the report on the testing of serial aircraft in 1943 year. I draw your attention, these were tests of serial aircraft, without any special modifications. The tests passed seven La-5 FN of different series, from May to December 1943. In general, the aircraft showed similar results: The maximum speed at the ground level is an average of 578 km / h. (from 570 to 587 km / h). In the simulator - 583 km / h, in the range. The maximum speed of 6 km is an average of 634 km / h (from 629 to 640 km / h). In the simulator - 646 km / h, only 1% faster. So in the simulator La-5FN speed it is quite consistent with the test data of serial aircraft.
  4. Gavrick

    Not a Spitfire OP thread

    That is, even at high speed the plane could develop such a high g-overload that there was a risk of breaking the structure.
  5. This is wrong point of view. It is necessary to take into account all available sources, not one "convenient". Once again. http://www.spitfireperformance.com/x4922.html http://www.spitfireperformance.com/w3134.html http://www.spitfireperformance.com/aa873.html Different airplanes, but similar top speeds. So, this data and these speeds can be trusted. http://www.spitfireperformance.com/aa878.html Report with information about +16 mode. But, at the same altitude as the previous three aircraft ("reliable data"), this slower by about 12 mph. So, at the ground level should be the same thing - this airplane should be slower. If we extrapolate speed graph at +16 to ground level, we have near 315 mph. 315+12 = 327. In simulator - 331 (40% radiator). near 1.5% mistake. Lets take a look at this graph. http://www.wwiiaircraftperformance.org/Spitfire_V_Level_Speed_RAE.jpg This plane a bit slower, that first three, but not so much as previous aircraft. And this airplane has a smaller speed increase, that previous aircraft (36 m.p.h. and 28...32 m.p.h.). Because of these circumstances, we can lose 4...8 m.p.h., depending on how to evaluate. But okay, let's say that 317 miles per hour from the chart is an exact figure and comparable to the simulator. 4% mistake, under ideal conditions in simulator (In the simulator, the aircraft can ideally withstand course and altitude). And it is still less that permissible error of 5%. And do not forget that the +16 mode is not eternal. Three minutes later the brougham turns into a pumpkin. 2 min "cooldown" is an error, and should be fixed, of course.
  6. About Spitfire maximal speed in level flight. First. About speed difference between +9 and +16 mode. We have two sources for +16 engine mode. That: http://www.spitfirep....com/aa878.html (Difference in speed between +9 and +16 below full throttle altitude is near 36 m.p.h.) And that: http://www.wwiiaircr...l_Speed_RAE.jpg (Difference in speed between +9 and +16 below full throttle altitude is 28...32 m.p.h.) In simulator, under ideal conditions, speed increases by approximatly 34.5 m.p.h. (below full throttle altitude). And it is close to both (36 m.p.h. and 28...32 m.p.h.) sources. Ok, now second. About maximal speed at +9 mode. If we compare that http://www.spitfirep....com/x4922.html , that http://www.spitfirep....com/w3134.html , and that http://www.spitfirep....com/aa873.html sources, we find that in all of them we have similar maximum speed in lewel flight (375 m.p.h., 371.0 m.p.h., 374 m.p.h.,). In simulator top speed - 367 m.p.h., but we hawe a snowguard, which decrease top speed. But in this report (which we already considered above, when talking about +16 mode) http://www.spitfirep....com/aa878.html top speed at +9 mode is only 359.5 m.p.h., and this is considerable slowly that top speed from other three reports. And, finally, we have that http://alternathisto...9_0-640x330.JPG data for lend-lease Spitfire with Merlin 46 from NII VVS tests (left kolumn, in k.p.h.) And this data close to Spitfire in simulator with Merlin 46 (near 10 k.p.h difference, less that 2%). So, after all, i think that Spitfire top speed in level flight in simulator close to real test flight data.
  7. Gavrick

    Spitfire stall and glide behavior

    In this report http://www.spitfirep....com/aa873.html stall speed - 81...90 m.p.h. with flaps and undercarriage up and 71 m.p.h. with flaps down. And, dont forget, that airspeed indicator has position error. -4 m.p.h. at low speed, that statued in flight manual. So, real stall speeds near- 85...94 and 75 m.p.h. (flaps up/down). And, if the stall speed were 73 miles per hour from pilot manual, then lift coefficient Cl should have been about 2.0 (for 3000kg Spitfire). This is fantastic value. I think, that is theoretical number, recalculates from early Spitfire. In the report above there is an example of such a recalculation with similar numbers.
  8. Gavrick

    Spitfire Pitch up / Pitch down

    The Spitfire really had an interesting feature in longitudinal channel controlablity. As already mentioned, Spitfire was a statically neutral airplane. As one of the manifestations of this - during acceleration or braking, the balancing position of stick does not practically change with it (see the excerpt from the NACA report). Unlike a conventional stable airplane, in which the lower the speed, the more you have to pull on yourself to maintain the balancing. That is, if you, for example, dive on the Spitfire - hold the stick the way it is set, the plane will accelerate and fly straight. But, at the same time, due to the peculiarities of the weight compensation of the elevator, force on the stick is changing, and strongly. And indeed, if you accelerate in a dive, then as the speed increases, stick will tend to go "on yourself", so the pilot has to push it away more and more from itself (that is, apply the same effort as on a stable aircraft), or twist the trimmer On the dive. Note - the forces applied to the stick vary, but the stick itself is practically stationary. Therefore, yes, indeed, as the speed increases, the aircraft must be trimmed to dive, and at the maximum permissible speed the trimmer must be twisted to a dive for the greater part of the stroke. By the way, on the indicator of the position of the trimmer, which is on the dashboard, the neutral trimmer on the handlebar is an arrow half a turn up from the neutral on the instrument. The range of the deviation for the dive is greater than for the trimming three times.
  9. The recovery time of the engine after a limited mode will be checked.
  10. Gavrick

    Spitfire stall and glide behavior

    About Spitfire stall. Spitfire is keep controllability in the stall. NACA report from Spitfireperformance: http://www.wwiiaircr...-V-Stalling.pdf Conclusion from this report: In general, from flight records from this report: Spitfire has unusual stall characteristics, motion beyound the stall is not violent and airplane still have lateral controllability. If you hold stick in position, required to start stall, airplane does not have a strong tendence to roll. If you continue pull stick, you may control aircraft by rudder and elevator beyound the stall. And from british flight tests (http://www.spitfireperformance.com/aa873.html): "At about 90 m.p.h. A.S.I. a considerable amount of buffeting around the hood commences. The A.S.I. can be reduced to 81 m.p.h. but at this speed sharp fore and aft pitching occurs together with increase of buffeting. This sharp fore and aft pitch prevents the control column from being held fully aft. In general the stall of the aeroplane is not clearly defined. There were no signs of either wing tending to drop. The elevator is moderately heavy though effectiveness has fallen off considerably."
  11. Gavrick

    Spitfire engine control management

    Thanks to everyone for the technical details found. Some materials I have not met before. As time will be, I will study and take into account.
  12. Gavrick

    News of our Beloved Spitfire?

    Yes. And you can check brakes by pressure in brakes gauge, at left side of control panel.
  13. Gavrick

    News of our Beloved Spitfire?

    Lets take a look to fig.9 and fig.11 from you link (NACA test report). Data at this figures taken from a sustained horizontal flight with different airspeed. We can evaluate the grade of static stability of the aircraft, based on these data. fig.9, Gliding condition (flaps and gears up), elevator angle at 100...120 mph is near 4...5 degree down. fig.11, Landing approach condition (flaps and gears down), elevator angle at 100...120 mph is near 3...4 degree down. That is, in this way, when flaps and gears down, elevator (and stick) remains almost in the same position as when flaps and gears up. Stick movement induced by pitching down moment is very small.
  14. Gavrick

    Spitfire Mk. VB mashup

    As I understand, this video uses inserts from the movie "The First of Few", 1942.
  15. Gavrick

    Developer Diary

    162 Hello everyone! So, let's talk about Supermarine Spitfire Mk.VB. It took off for the first time in December 1940. Spitfires V were relatively old planes by the time the battle of Kuban begun in Spring 1943. "VB" variant was armed with two 20 mm Hispano Mk. II guns and four Browning .303 machine guns. The guns were magazine-fed, 60 rounds per gun, while machine guns had 350 rounds per gun. The lend-lease aircraft sent to the USSR did not have bomb-carrying capabilities, some other equipment was also removed - gun camera, landing lights, IFF transponder, etc. Thanks to this, the aircraft became lighter roughly by 40 kilograms. The special snowguard was installed in front of the engine supercharger to protect it from dust or snow while taking off. Most of the planes sent to the USSR had Merlin 46 engine, but roughly one-fifth of them was equipped with Merlin 45. They differed by critical altitudes - Merlin 46 was designed for higher altitudes like 4-5 kilometers, where it was more powerful, but it was 80-100 HP weaker than Merlin 45 near the ground. Our sim will represent both engines (Merlin 45 will be a modification). Spitfire instruments are similar to other planes, but there were some peculiarities. It was equipped with the rudder and elevator trimmers and the elevator trimmer position was shown on the instruments panel. The pitch up range of the trimmer is three times larger than pitch down. The engine-propeller combination is controlled by the throttle, the automatic pressure limiter switch, the propeller control unit and the mixture control assembly. The throttle is linked to the automatic supercharger: when the throttle is set to any position from 1/3 to full, it sets a pressure supported by the supercharger from -7 to +12 pounds per square inch (PSI) relative to one atmosphere pressure. So 760 mmHg boost equals to 1 ATA and to +0 position on the British boost indicator. The automatic pressure limiter can be turned off to maintain constant +16 boost regardless of the throttle position. The automatic mixture controller maintains the optimal mixture setting if its control level is in the forward position or leaned mixture to save fuel if its control level is in the back position. The mixture control system has been removed on later Spitfires. Water radiator is controlled by the lever to the left of the pilot seat which has six fixed positions and is set to 40% by default. The fuel gauge indicates the amount of fuel left in the feeder (bottom) tank when the fuel gauge button is pressed. In the sim, the pilot automatically presses the button twice in a minute if he doesn't do active maneuvering. The amount of fuel left in the upper fuel tank can't be indicated. Spitfire is equipped with a siren that warns a pilot if the throttle is set to a low position with the landing gear retracted. It turns off when the pilot either lowers the landing gear or increases the throttle or turns it off manually (in our sim the pilot turns the siren off after 3-5 seconds on its own). The sideslip indicator isn't a small ball like on other planes, but an arrow. It functions essentially the same - there is a pendulum behind the instruments panel attached to this arrow. The aircraft is equipped with two compasses - magnetic and gyro ones. Gyro compass should be caged up on the ground and while doing aerobatics (in the sim the pilot does on its own). There is a flight timer on the clock that is turned on by the pilot on its own after takeoff and turned off after landing. Upper and bottom formation lights can be turned on simultaneously or independently (RAlt+L). The horizontal marks on the collimator gunsight are adjustable, so you can use it like a rangefinder. To do this, enter the target distance in yards and the target base (its wingspan) in feet by pressing RAlt + , RAlt + ; and RAlt + /. There is a sun filter on the gunsight. While taxiing, keep in mind that Spitfire has narrow landing gear and large wings stuffed with weapons and ammunition, so they may touch the ground if you attempt a sharp turn, it also tends to 'circle'. On the other hand, it is stable on the runway during takeoff or landing. Its tail wheel rotates freely and does not have a lock. Take off should be made at 3000 RPM and +12 boost with the landing flaps retracted. When airborne, reduce the boost to +9 and RPM to 2850 and climb in this mode. The elevator is very sensitive and has very small stability reserve (the aircraft has a neutral static stability), so control the plane by gentle flight stick movements and don't overdo it. The pre-stall warning shake comes early, but if you continue to pull the flight stick and don't move it forward, the plane may stall and spin even at high speed. Flight manual says that you may enter spin only by a written permission of your squadron commander. Having the papers ready, enter the spin bravely - to recover from the spin, setting the control surfaces to the neutral position is enough usually. As we mentioned above, the aircraft has a neutral static stability. Therefore, the balanced flight stick position doesn't change during level flight while accelerating or decelerating. However, due to the elevator peculiarities, the flight stick load will change and the pilot should push the stick forward harder as the speed increases. That's why the elevator trimmer has the large pitch down range. The elevator effectiveness is high, so any trimmer position could lead to high-g accelerations (and force pilot to blackout rapidly) at higher speeds in spite of the limited control surfaces effectiveness at high speeds. The aircraft, especially untrimmed, should be controlled carefully at high speeds, not giving too much flight stick input since the high-g accelerations can potentially lead to a catastrophic structural failure. The aircraft becomes somewhat unstable with extended landing flaps, but in spite of this, it is easy to land. It's recommended to keep 95-100 MPH speed on the glide path. To summarize, Spitfire is a maneuverable, relatively easy to control and decently armed aircraft. However, its maneuverability (that comes from its large wing surface of 22.5 square meters, while Soviet fighters had ~17.5 sq.m. and Bf 109 had 16.2 sq.m) comes with the price of modest maximal speed near the ground. https://youtu.be/MgL_nLVGmng You can discuss the news in this thread
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