00:Home
30:Bases
40:Maps
50:R.O.E.
60:Crews
70:More
80:Story
11:Weapons
13:Targets

2014.08.19

 
 
  
  
  
AAC AIRCRAFT GUNS COMPARATIVE
 
MM Anthony G. Williams and Emmanuel Gustin have published two interresting articles regarding the future of aircraft guns ("Will the Fighter Gun Survive ?") and gun effectiveness ("Modern Fighter Gun Effectiveness").  Both these articles are reproduced on this website, together with another article about "Historical Machine Gun Cartridges" also reproduced on this website.

While Atlantic Air Combat is only intended as an improved "arcade" type game rather than a real "simulation" one, we neverthless try to stick to historical reality.  For instance, should AAD incorporate the Aero S-92 (post-war Czech version of the Me 262), it would then be equipped with the proper guns.   However, there are instances where an existing aircraft will be "modernized" by a fictional operator (re: the F6U Pirate for the Spanish Navy), with (among other things) new guns.   As the game involve "events" happening the early 1960s, on-board guns do play an important role and one must recognize that in such a game, spreading bullets in the landscape, preferably on target (!), is part of the fun.

At this preliminary stage, the choice of guns for a fictionally modernized aircraft or for a totally fantasy one (eg: the Argentinian VJ101E) has been made using the rule of the thumb.   However, the above mentioned studies do provide an interresting approach to "gun efficiency" and a similar approach will be used here, either to lead to changes to these fictional aircrafts or to show how it stands in comparison with the original design or with other aircrafts in general.

The tables accompanying the above mentioned articles are complex and include factors like the installation weight to measure gun efficiency.  This particular aspect will be excluded here.   In the context of AAC, installation weight is only taken into account to ensure the feasibility of a "cheat", and that aspect is taken care of in the notes accompanying a given aircraft.

This somewhat different approach is not intended to trigger any polemic about those studies as the below table actually rest on the same methods.  Actually the comments about the various values are directly copied from these articles.  The present Notes do not bring anything new in that respect as they only show identical or similar values organized in a slightly different manner.  Therefore, the credit of any data contained here must go exclusively to the authors of these articles, namely MM Anthony G. Williams and Emmanuel Gustin.  The reader is invited to read those articles before going any further.

Cartridge destructiveness (a summary of the details and calculation methods outlined in the articles referred to)
   
Projectiles relying exclusively on kinetic energy are assigned a 10O% effectivness factor
Projectiles with a chemical (explosive and/or incendiary) content see their effectiveness increased by the weight fraction of that chemical content, times ten
The 'DAMAGE' column shows the results of the following calculations (shell, projectile, bullet are here synonyms)
Example 30x113B (Aden gun) _________ _________
1) Momentum Shell weight in kg x muzzle speed in m/s 0.236kg x 740 m/s = 174.6    
2) Effectivness explosive (kg) projectile (kg) 10 + 1 0.050kg 0.236kg = 0.212 x10 + 1 = 3.12  
3) Damage Momentum x Effectiveness 174.6 x 3.12 = 544.752 >>>>>>>>

545

4) Ammo Power Damage 10 545 10 >>>>>>> >>>>>>> >>>>>>>>

54.5

5) Gun Power Ammo power x rate of fire (RPS) 54.5 x 21.7 >>>>>>> >>>>>>> >>>>>>>

1183

  
The cartridge destructiveness only shows the relative effect of one hit.  When comparing guns firing the same cartridge, another factor comes into play, namely the rate of fire (RoF).  To calculate the destructive power of a gun, the 'AMMO POWER' factor is multiplied by the RoF.  While usually expressed in rounds fired per minute (RPM), it is here expressed in the number of rounds fired per second (RPS). This gives the relative 'GUN POWER' figures in the table below.  For a given aircraft, the GUN POWER has to be multiplied by the number of guns installed.

The final column gives the time in seconds, needed to fire the equivalent of an ammunition power of "2320".  The choice of this value is somewhat arbitrary; it was selected simply because the heaviest armed WW2 fighter the Me 262 was capable of delivering this firepower in one second.  A reference being chose, it allows easy comparisons to be made. '

The original tables show to 'Time to Fire 2320' figures for American rotary guns as this particular type need a little time to reach their nominal rate of fire.   For example, the M61A1 only fires 18 rounds in the half of a second, and 68 rounds in the first full second of firing.  In the context of AAC, this particularity is not taken into account.  The M61A1 gun equiping the F-104 Starfighter being rated at 6000rmp (100 rps), it will fire at that rate from the first second.  There are two reasons for this :

it's an element in simplification in the game design
it seems that, in real life, it is possible to pre-spin a rotary gun prior actual firing; when exercised, it allows a pilot to immediately take full advantage of the gun firing rate without being hindered by a spin-up time, however shot it may be
   
AAC FIGHTER AIRCRAFT GUN POWER TABLE
   
Most of the columns headers are explained in the above notes  -  the "Q" column refers to the number of guns installed on an aircraft
Some aircraft are fictional or fictional variants of an historical type, and some guns are fictional too (re: Oerlikon Rk304/30 firing 30x173mm ammo).  Finally some data have been arbitrarily set as thery are, either because they were missing or for reason of convenience  -  these "cheats" are shown in red
Various types of ammuntion being available to guns, data is presumably for APHEI rounds.  With data varying according to information source, the Table results are based on AAC ammunition data.  So, while the methodology is the same as in the reference tables, results may be slightly different, it nevertheless allows similar comparisons to be made  -  any constructive comment welcome, especially when spotting an error !
The Me262 - here identified as the Aero S92 - original reference data (re: Williams/Gustin) is shown on the first line
Aircraft and gun designations are those used within AAC
Two guns are not related to internal aircraft equipment (unless future cheat) : the Soviet 14.5mm KPV, and the American 20mm Mk11
Another approach to gun comparison is sometimes used within AAC pages, especially when exploring various potential gun equipment for a "cheat" aircraft (eg : VJ101E).   At this moment, this different approach is not incorporated in the Table;
-
-
 .  .  
This table being "under construction", ammunitions/guns performances are shown without direct link to an aircraft - the table content with evolve with time, as AAC aircrafts types are further defined.  A first "cheat" example is shown for which the gun armament is being studied (VJ101E)
   
   
 Aircraft Name Ammo HEI
(g)
HEI
(%r)
Shell
(g)
Eff Muzzle
(m/s)
Mom Dam
age
Ammo
Power
Q Gun RPM
@
RPS
@
Gun
Power
Aicraft
Power
Time  to 
2320 
 S92 Turbina 300x  90 83g 25% 330g - 540 - 580 58.0 4 MG108/30 600 10.0 580 2320 1.00 
 VJ101E Busardo_V1=M61 200x102 11g 10.8% 102g 2.08 1030 105.1 219 21.9 1 M61A1 1200 100.0 2190 2190 1.06 
 VJ101E Busardo_V2=M39 200x102 11g 10.8% 102g 2.08 1030 105.1 219 21.9 2 M39/20 1500 25.0 548 1096 2.17 
 VJ101E Busardo_V3=M47a 200x110 11g 10.8% 102g 2.08 840 85.7 178 17.8 2 M47/20 750 12.5 222 444 5.23 
 VJ101E Busardo_V4=M47b 200x110 11g 10.8% 102g 2.08 840 85.7 178 17.8 4 M47/20 750 12.5 222 888 2.61 
 VJ101E Busardo_V5=M44 132x  99 8g 15.7% 51g 2.57 900 45.9 118 11.8 4 M44/132 900 15.0 177 708 3.28 


















- - 762x  39 1g 12.5% 8g 2.25 800 6.4 14 1.4 30CalShk 1800 30.0 43 - -
- - 762x  51 1g 9.1% 11g 1.90 850 9.3 18 1.8 30CalM2 1200 20.0 36 - -
- - 127x  99 2g 4.6% 43g 1.46 880 37.8 55 5.5 50CalM2 750 12.5 69 - -
- - 127x  99 2g 4.6% 43g 1.46 880 37.8 55 5.5 50CalM3 1200 20.0 110 - -
- - 127x108 4g 8.3% 48g 1.83 840 40.3 74 7.4 UBS/127 750 12.5 93 - -
- - 130x  64 2g 5.9% 34g 1.59 750 25.5 41 4.1 MG131/13 900 15.0 61 - -
- - 132x  99 8g 15.7% 51g 2.57 900 45.9 118 11.8 4 M44/132 900 15.0 177 - -
 ///// LAA-Gun 145x115 5g 8.6% 58g 1.86 1000 58.0 108 10.8 KPV145 600 10.0 108 - -
- - 150x  96 5g 8.8% 57g 1.88 805 45.9 86 8.6 MG151/15 750 12.5 107 - -
- - 200x  96 4g 3.5% 115g 1.35 805 92.6 125 12.5 MG151/20 750 12.5 156 - -
- - 200x  99 6g 6.3% 96g 1.63 750 72.0 117 11.7 ShAK/20 750 12.5 146 - -
- - 200x  99 6g 6.3% 96g 1.63 750 72.0 117 11.7 BZN/20 780 13.0 152 - -
- - 200x102 11g 10.8% 102g 2.08 1030 105.1 219 21.9 M39/20 1500 25.0 548 - -
- - 200x102 11g 10.8% 102g 2.08 1030 105.1 219 21.9 M61A1 1200 100.0 2190 - -
- - 200x110 11g 10.8% 102g 2.08 840 85.7 178 17.8 M47/20 750 12.5 222 - -
- - 200x110 11g 10.8% 102g 2.08 880 89.8 187 18.7 HSMk2 600 10.0 187 - -
- - 200x110 11g 10.8% 102g 2.08 840 85.7 178 17.8 HSMk5 750 12.5 222 - -
- - 200x110 11g 10.8% 102g 2.08 880 89.8 187 18.7 M2/20 600 10.0 187 - -
- - 200x110 11g 10.8% 102g 2.08 800 81.6 170 17.0 M3/20 750 12.5 212 - -
- - 200x110 11g 10.8% 102g 2.08 800 81.6 170 17.0 M24/20 750 12.5 212 - -
- - 200x110 11g 10.8% 102g 2.08 1010 103.0 214 21.4 M12/20 1000 16.7 357 - -
 ///// Gunpod 200x110 11g 10.8% 102g 2.08 1050 107.1 223 22.3 M11/20 4200 70.0 1561 - -
- - 230x115 19g 10.8% 175g 2.08 710 124.3 258 25.8 AM/23 1200 20.0 516 - -
- - 230x115 19g 10.8% 175g 2.08 700 122.5 255 25.5 NS/23 600 10.0 255 - -
- - 230x115 19g 10.8% 175g 2.08 800 140.0 291 29.1 NR/23 800 13.3 387 - -
- - 230x115 19g 10.8% 175g 2.08 715 125.1 260 26.0 GsH23L 3420 57.0 1482 - -
- - 230x260 19g 10.8% 175g 2.08 900 157.5 328 32.8 RR/23 2000 33.3 984 - -
- - 230x152 7g 3.3% 210g 1.33 880 154.0 320 32.0 VY/23 540 9.0 288 - -
- - 300x113 50g 21.2% 236g 3.12 815 192.3 600 60.0 Defa/30 1200 20.0 1200 - -
- - 300x113 50g 21.2% 236g 3.12 740 174.6 545 54.5 Aden/30 1300 21.7 1183 - -
- - 300x  97 63g 21.3% 296g 3.13 670 198.3 621 62.1 Rk251/30 1400 23.3 1447 - -
- - 300x173 76g 21.1% 360g 3.11 1080 388.8 1209 120.9 Rk304/30 1350 22.5 2720 - -
- - 300x165 50g 12.5% 400g 2.25 900 360.0 810 81.0 NR/30 900 15.0 1215 - -
- - 370x145 48g 7.9% 608g 1.79 610 370.9 664 66.4 M04/37 150 2.5 166 - -
- - 370x145 48g 7.9% 608g 1.79 610 370.9 664 66.4 M10/37 180 3.0 199 - -
- - 370x195 50g 6.8% 735g 1.68 880 646.8 1087 108.7 NS/37 250 4.2 457 - -
- - 370x155 50g 6.7% 750g 1.67 690 517.5 864 86.4 NRD/37 400 6.7 579 - -
- - 370x155 50g 6.7% 750g 1.67 690 517.5 864 86.4 NRN/37 650 10.8 933 - -
- - 570x230 120g 5.4% 2230g 1.53 744 1659.1 2538 253.8 M47/57 100 1.67 424 - -
- - - - - - - - - - - - - - - - -