Interceptor Shield Strength Study
Executive Summary
A study was carried out to estimate Thargoid Interceptor shield strength. By employing a model of Interceptor shield decay and human weapon damage, the shield strength of all four Interceptor variants was measured. The table below shows the starting shield strength of each Interceptor.
Initially, when the shield strength was estimated using various types of weapons, namely Laser Beams and Multi-Cannons, it was found that different types of damage have a greater or lesser effectiveness against the shield and thus yielded contradictory results. A breakthrough in the study came when it was realized that
Interceptor shields have the same resistances and vulnerabilities as unengineered human shield generators. The magnitude of each damage component in a given weapon was scaled according to the standard resistance of 50%, 40%, and -20% for explosive, kinetic, and thermal damage, respectively. The shield strength measurements were then consistent across weapon types within experimental errors.
Additionally, the following set observations were made:
- As expected based on standard resistances, thermal damage is the most effective against Interceptor shields. Laser beams and weapons with the incendiary experimental effect are most effective.
- Explosive damage is the weakest of all four types. Additionally, the Interceptor shield has a 30% chance of deflecting incoming missiles without incurring any damage.
The damage output of railguns seems to be 60% thermal and 40% kinetic. That was the damage partitioning that was the most consistent with other results.
- The damage partitioning of absolute, thermal, and kinetic damage for Plasma Accelerators seems to be closer to 60/10/30 instead of the oft-quoted 60/20/20.
- Update: These results are somewhat of an anomaly because more detailed calculations of PAs show that the partition of damage is indeed 60/20/20
- Multi-cannons with the incendiary experimental effect seem to have damage that consists of 90% thermal and 10% kinetic as shield measurements that assumed 100% thermal damage were not consistent with those of Beam weapons.
- The absolute shield decay rate of all Interceptor types seems to be around 24.5 MJ/s. Higher level variants have shields that last longer because they simply have a higher starting magnitude.
Theory
The cornerstone of this analysis is that Interceptor shields exhibit a linear shield decay rate. The shield strength of an Interceptor will decay from 100% to 90% at the same rate that it does from 10% to 0%. When left unperturbed, the shield strength of a given Interceptor variant will decay from 100% to 0% in a fixed period of time T_0. Now, when damage is inflicted on the shield by a weapon, the shield will reach a 0% sooner, at a time T_1. This can be easily visualized by considering the unperturbed case and the scenario where the shield is continuously damaged by a beam weapon, as shown in the figure below.
The essence of the argument is that we know how much damage was dealt to the shield, and we know what fraction of the shield was supposed to be left at time T_1. Based on those two pieces of information---the damage dealt by the weapon and the baseline fractional shield at a given moment---we can infer the initial shield strength of the Interceptor shield. The formal equations for estimating the shield strength are given below.
During the course of this study, it was hypothesized that the Interceptor shield has the same resistances as standard, unengineered human shield generators: 50%, 40%, and -20% for explosive, kinetic, and thermal damage, respectively. This assumption made a significant difference in making the estimates from various weapons coincide with one another.
For a given weapon, such as Railgun or Plasma Accelerator, the partition of damage between the individual components of the weapon were taken from assumptions made by members of the Pilot’s Federation. During the course of this analysis, those parameters had to be adjusted in order for the shield estimates to match. For instance, the damage partition for Railguns was initially assumed to be 50/50, but was later revised to the 60/40 (thermal/kinetic) because it seemed to fit the data more closely.
The full analysis study can be found here:
https://docs.google.com/document/d/1E4dRI-1nXyjzr68la07gudNV2wVf5e6mBigFAjQBD8s/edit?usp=sharing
