Truesilver's Tests, No.2: Rail gun thermic-kinetic damage split

In response to a personal question received, arising out of a current thread, I’ve decided to usurp the planned Truesilver’s Tests No.2 (Felicia Winters’ Pulse Disruptor) and replace it with proof of the balance between thermic and kinetic rail gun damage.

To recap, all damage in Elite: Dangerous is either non-specific (the only example of which is collision damage), thermic (like lasers), kinetic (like multi-cannons) or explosive (like missiles). However, two types of weapon – the rail gun and the plasma accelerator – are ‘thermic-kinetic’, in that they incorporate a mixture of both damage types. These portions then each receive a separate damage calculation on striking a target before the game aggregates the whole.

The relevance of damage type is that it provides a modifier to base damage depending upon what the weapon is hitting: a shield, an unmodified hull (that is, one fitted with light, reinforced or military bulkheads) or a modified hull (one fitted with mirrored or reactive bulkheads).

The full list of modifiers has been obtained for us in an FDev email by Cmdr Frentox, whose superb thread here on piercing & hardness …

https://forums.frontier.co.uk/showthread.php?t=224474

… sets out the damage modifiers as being:

TARGETTHERMALKINETICEXPLOSIVE
Shields120%60%10%
Unmodified100%120%140%
Mirrored50%175%150%
Reactive140%75%80%

Assuming that to be correct, we can determine the damage component of any weapon by shooting it at different hulls, noting the results and then backwards-calculating by reference to the modifiers above.

The rail gun thermic-kinetic split has for a long time said to be 70-30 and this in turn was said to have originated from FDev, although I have been unable to find the original source for that. However, PvP-ers everywhere have been able to see, from in-battle observation, that the weapon certainly is more effective against shields than hulls, with the principal hull benefit being its module penetration. I myself for a long time used the ’70-30’ rule.

However, during the rigours of the recent PvP League Season 1, I decided to establish the balance once and for all. Assisted by Cmdr Erich Zann (using his alternate account, Cmdr Philip J Fry – thanks again to you both!) we carried out a controlled test by firing over 50 standard medium rail gun shots first at a FdL equipped with military bulkheads and then at the same FdL equipped with mirrored bulkheads.

The test method was as follows: Erich both times established the same firing position precisely 500m from my FdL, then cycled through all my subsystems to check visually that none would be struck by the rail gun slug. Erich then switched off his thrusters to ensure that his ship could not move during test firing. Meanwhile, between each shot, I checked my right-panel to ensure that no module damage had been sustained (because when a module is damaged, the hull takes only a minority of the total damage of the shot).

We did this over 100 times, on video, with no modules struck and with the damage done by each shot to my hull checked using the left-panel, one by one, and noted. We compared our notes and I checked the videos. Results were consistent throughout, as follows.

Every 10 shots to the military hull did 7/6 the damage of every corresponding 10 shots to the mirrored hull. 50 shots to the military hull did 7/6 the damage of 50 shots to the mirrored hull, etc.

Hence the mirrored hull FdL took 85% of the damage that the unmodified FdL took when exposed to rail gun fire.

Backwards calculation by reference to the modifiers obtained by Cmdr Frenotx reveals that rail gun damage is therefore 2-1 thermic-kinetic or a 66.6% to 33.3% split.

(For those really interested, the mirrored/military figure was actually 0.857 and the backwards calculation 0.859 but the 0.002 difference is well within the error margin.)

Bearing in mind that the final 66.6 to 33.3 is only about 3.3% different to the 70-30 that we previously thought, it is perhaps unsurprising that nobody has previously spotted the discrepancy.

Of course, the backwards calculation depends upon the validity/accuracy of the FDev email, which I can’t personally vouch for. But it does all seems to stack up ;)

Unless someone is able to provide us with more information (and of course I welcome all corrections or comments) I therefore believe the thermic-kinetic rail gun damage split to be established as a simple 2:1 ratio.

As a historical footnote, the principal purpose of Adle’s Armada carrying out the testing above was so that we could decide whether to fit our stealth ships with mirrored rather than military bulkheads during the latter stages of the PvP League – because we were concerned that opponents might use our own rail-based builds against us. Although the testing revealed that this would have reduced all-rail damage against us to 85% of military, the consensus was that the risk of facing mixed builds (eg rails + frags) was too great and that we would be better off sticking with military bulkheads – which is indeed what all our pilots used throughout.

Coming next in Truesilver’s Tests, No.3: Felicia Winters’ Pulse Disruptor – including subsystem disruption rate comparison with other weapons.

See you in the black!


TRUESILVER

Adle’s Armada
www.inara.cz/wing/336


For Truesilver's Tests, No.1: The Imperial Hammer, see:
https://forums.frontier.co.uk/showthread.php?t=236030

For my all weapons hull damage thread see:
https://forums.frontier.co.uk/showthread.php?t=226355
 
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Although the testing revealed that this would have reduced all-rail damage against us to 85% of military, the consensus was that the risk of facing mixed builds (eg rails + frags) was too great and that we would be better off sticking with military bulkheads – which is indeed what all our pilots used throughout.
An interesting analysis. Thanks

This is exactly why I've never bothered paying the extra for the mirrored or reactive armour. It's rare that you have an encounter when only thermic or only kinetic weapons are used so it's not worth having increased protection against one of them at the expense of the other.
 
Nice thread. I'll continue to stick with military armor on my ships unless I'm doing something shieldless w/silent running to account for potential non-rail kinetic damage.
 
Wasn't this tested long time ago already
Hi Hoodini,

No, I'm not aware of any previous confirmation and publication of the thermic-kinetic rail gun damage split but if you can point me to something specific I would be glad to consider, o7

Truesilver
 
I was referring to the information provided in the video and link showing the damage taken vs different armor types from different weapons and specifically for railguns which leads people to take the military armor and not spend extra money for the little extra the mirrored one gives.
 
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