almost 2 years ago - Stona - Direct link

Initially, the ‘distant hand’ for the MiG-29 in War Thunder were the R-27 missiles with heat and radar seekers. The missile features slightly better maneuverability than other medium range missiles in the game, though in the stock version its launch range is crucially lower than AIM-7F’s, which is the ‘distant hand’ of the American F-14 and F-16, and even slightly lower than R-24 fire range due to the lower thrust. Considering that the second component of the MiG-29’s air-to-air guided weapon, the R-60M, is inferior to the AIM-9L in terms of its combat characteristics, we decided to equip the Fulcrum with and advanced missile of the R-27 family, the R-27ER with a radar seeker, which has a slightly higher power-to-weight ratio than the AIM-7F, but, given the shorter operating time of the on-board equipment, has identical fire range with the AIM-7F.







Missile






AIM-7F






R-24R






R-27R






R-27ER





ΣΔV, m/sec






950






735






720






1190





Weight, kg






231






244






253






350





Power-to-weight ratio, kg*p/kg






84






63






62






94





Guidance time, sec






75






45






60






60





Front aspect launch range (Vl=Vt=1M), km






43






33






35






44





Front aspect launch range (Vl=Vt=2M, N+10 km), km






94






48






74






85





Maximal transversal acceleration, G






25






25






30






30




Сomparison chart of the parameters of R-24R, R-27R, R-27ER and AIM7F missiles




As you can see, the specific power-to-weight ratio of the R-27 is lower than the R-24’s. Unfortunately, we have no data about the reason for this, but we can assume that it is due to a heavier modular design.



As for the R-27ER missile, it is important to note that, due to the better power-to-weight ratio among medium-range missiles, it outperforms the AIM-7F in acceleration dynamics, which improves its efficiency at medium distances. But at high altitude and at high launch speeds, the AIM-7F can outperform the R-27ER due to its longer guidance time.


The MiG-29’s available thrust


After the MiG-29 was added to War Thunder, we received many questions, why the static thrust of the aircraft in the game is lower than that declared by the manufacturer. There are many reasons for this, let us list the main ones.




Static thrust in full afterburner mode and no afterburner max speed are 8,300 kgf and 5,040 kgf. This thrust is given by the manufacturer for conditions of 0 m and 0 km/h, without taking into account the loss of thrust in the air intake ducts, power supply of onboard equipment and other factors that rise when the engine is mounted in the aircraft.




According to the main source about the aircraft (“Аэродинамика самолёта МиГ-29”) ", the static thrust of the installed engine in the full afterburner mode (see “ПОЛНЫЙ ФОРСАЖ”) is about 8,000 kgf, and in the maximum speed mode (see “МАКСИМАЛ”) about 4,900 kgf, which are 300 kgf and 100 kgf, respectively, lower than declared. The graphs below do not reflect the influence of the MiG-29 inlet devices, which are represented by the blow-in door of the critical section of the air intake duct at the inlet, as well as the upper air intakes. In the take-off mode, the blow-in doors completely block the axial inlet of the air intake to prevent solid objects from entering it and damaging the engine, and all air supply to the engine goes through small slots in the lower part of the door, as well as through the upper inlet. The engine in this mode operates with a lack of air and is not able to gain the thrust indicated in graphs 3.16 and 3.17.




At lower speeds the listed performance can not be achieved either. Due to the uneven mixing of flows from the upper and axial inlets, the air flow at the air intake is unstable, which results in the engine not having sufficient air supply. This phenomenon is described in the same source.




Furthermore, the engine is controlled and adjusted by a number of automatic systems, which may also cut thrust and engine speed.




As a result, the listed factors reduce the available thrust, affecting it most at lower speeds. The graph of the available thrust displays the full afterburner and full speed modes. Since our flight model operates the available thrust, this static available thrust is presented in the engine performance in the game.




The estimated available thrust also coincides with the estimates indirectly calculated from the graphs of the available longitudinal acceleration Nx (Fig. 5.3, 5.4), which, in fact, display the aircraft's thrust-to-weight ratio minus the required thrust. The amount of available thrust is also confirmed by the graphs of maximum speeds, graphs of rate of climb, graphs of turn rates, as well as the take-off rate from the moment the brakes are released and the available acceleration at the start (paragraph 8.3.2 of the source). At the moment, the aircraft in the game shows all these characteristics quite close to the declared ones or even slightly exceeds them.

almost 2 years ago - Stona - Direct link

Initially, the ‘distant hand’ for the MiG-29 in War Thunder were the R-27 missiles with heat and radar seekers. The missile features slightly better maneuverability than other medium range missiles in the game, though in the stock version its launch range is crucially lower than AIM-7F’s, which is the ‘distant hand’ of the American F-14 and F-16, and even slightly lower than R-24 fire range due to the lower thrust. Considering that the second component of the MiG-29’s air-to-air guided weapon, the R-60M, is inferior to the AIM-9L in terms of its combat characteristics, we decided to equip the Fulcrum with and advanced missile of the R-27 family, the R-27ER with a radar seeker, which has a slightly higher power-to-weight ratio than the AIM-7F, but, given the shorter operating time of the on-board equipment, has identical fire range with the AIM-7F.







Missile






AIM-7F






R-24R






R-27R






R-27ER





ΣΔV, m/sec






950






735






720






1190





Weight, kg






231






244






253






350





Power-to-weight ratio, kg*p/kg






84






63






62






94





Guidance time, sec






75






45






60






60





Front aspect launch range (Vl=Vt=1M), km






43






33






35






44





Front aspect launch range (Vl=Vt=2M, N+10 km), km






94






48






74






85





Maximal transversal acceleration, G






25






25






30






30




Сomparison chart of the parameters of R-24R, R-27R, R-27ER and AIM7F missiles




As you can see, the specific power-to-weight ratio of the R-27 is lower than the R-24’s. Unfortunately, we have no data about the reason for this, but we can assume that it is due to a heavier modular design.



As for the R-27ER missile, it is important to note that, due to the better power-to-weight ratio among medium-range missiles, it outperforms the AIM-7F in acceleration dynamics, which improves its efficiency at medium distances. But at high altitude and at high launch speeds, the AIM-7F can outperform the R-27ER due to its longer guidance time.


The MiG-29’s available thrust


After the MiG-29 was added to War Thunder, we received many questions, why the static thrust of the aircraft in the game is lower than that declared by the manufacturer. There are many reasons for this, let us list the main ones.




Static thrust in full afterburner mode and no afterburner max speed are 8,300 kgf and 5,040 kgf. This thrust is given by the manufacturer for conditions of 0 m and 0 km/h, without taking into account the loss of thrust in the air intake ducts, power supply of onboard equipment and other factors that rise when the engine is mounted in the aircraft.




According to the main source about the aircraft (“Аэродинамика самолёта МиГ-29”) ", the static thrust of the installed engine in the full afterburner mode (see “ПОЛНЫЙ ФОРСАЖ”) is about 8,000 kgf, and in the maximum speed mode (see “МАКСИМАЛ”) about 4,900 kgf, which are 300 kgf and 100 kgf, respectively, lower than declared. The graphs below do not reflect the influence of the MiG-29 inlet devices, which are represented by the blow-in door of the critical section of the air intake duct at the inlet, as well as the upper air intakes. In the take-off mode, the blow-in doors completely block the axial inlet of the air intake to prevent solid objects from entering it and damaging the engine, and all air supply to the engine goes through small slots in the lower part of the door, as well as through the upper inlet. The engine in this mode operates with a lack of air and is not able to gain the thrust indicated in graphs 3.16 and 3.17.




At lower speeds the listed performance can not be achieved either. Due to the uneven mixing of flows from the upper and axial inlets, the air flow at the air intake is unstable, which results in the engine not having sufficient air supply. This phenomenon is described in the same source.




Furthermore, the engine is controlled and adjusted by a number of automatic systems, which may also cut thrust and engine speed.




As a result, the listed factors reduce the available thrust, affecting it most at lower speeds. The graph of the available thrust displays the full afterburner and full speed modes. Since our flight model operates the available thrust, this static available thrust is presented in the engine performance in the game.




The estimated available thrust also coincides with the estimates indirectly calculated from the graphs of the available longitudinal acceleration Nx (Fig. 5.3, 5.4), which, in fact, display the aircraft's thrust-to-weight ratio minus the required thrust. The amount of available thrust is also confirmed by the graphs of maximum speeds, graphs of rate of climb, graphs of turn rates, as well as the take-off rate from the moment the brakes are released and the available acceleration at the start (paragraph 8.3.2 of the source). At the moment, the aircraft in the game shows all these characteristics quite close to the declared ones or even slightly exceeds them.


Discussion thread

almost 2 years ago - Smin1080p - Direct link

If something is believed to be over / under performing in some way and evidence that meets the criteria has been gathered, then a report should be made for the Devs to review.


Discussion topics are not the way to go about reporting an issue if you believe it is one.

almost 2 years ago - Smin1080p - Direct link

This would be correct for this report. Missiles often have to be configured a certain way to achieve certain performance factors in game.


AIM-7F is configured to reach 3.3/9.5nm when launched into the rear hemisphere under conditions corresponding to these diagrams:

almost 2 years ago - Smin1080p - Direct link

Client data (datamines) cant be used for reports. All the visible information in game (stat cards, in game testing) can be used.

almost 2 years ago - Smin1080p - Direct link

Its down to the developers to make that decision. Its not simply a case of your method of calculating shows it may be wrong, therefor it is.


Your welcome to submit reports with material to support your claims for consideration.

almost 2 years ago - Smin1080p - Direct link

Datamined information cant be used in reports for the very reason that it can often appear wrong because its being interpreted wrong. Certain values have to sometimes be coded in particular ways to achieve certain in game outcomes. This is why values can often appear incorrect and why we don't allow reports from datamining, because the values there often are not a reflect of the real in game ones or people have misinterpreted them entirely.


Even if it is the case that the values are wrong leading to an issue, datamines cannot be used for reporting. This criteria has been set by the developers for a reason and has been made clear many times now. Reports must use in game tests or the visible values the game provides.



If this is the case, then there is no reason to be discussing it further at this time until there is a final outcome