One of the recent buzzword bingo entries that has caught on is “kill chain”. In simple terms it’s the sequence of events that lead to ordnance on target. The simplest kill chain is,
see the target
pull the trigger
Simple. Easy to understand. Reliable.
A more common kill chain as envisioned by today’s Navy is,
sense the target via multiple sensors
transfer the data to a common data processing location
fuse the sensor data into a common tactical picture
assess the tactical picture against overall objectives
obtain Command and Control (C2) guidance and approval
assign a specific weapon
transfer targeting data to the shooting platform
hand off mid-course guidance to another platform
Think I’m making up a complex chain like that just to make a point?
Consider the recently discussed kill chain involving the LRASM guided by a chain of F-35s transmitting and retransmitting data back to a central fused tactical data center, then to the shooting platform and back out to the F-35 for guidance and possible re-programming. The chain might also include data relay stations in the form of satellites or other aircraft.
Still not sure this is realistic?
Consider the Navy’s Co-operative Engagement Capability (CEC). Multiple platforms share data to assemble a common tactical picture which is evaluated by the air defense command function which then assigns weapons and launch platforms. Mid-course guidance may come from any platform. That’s an actual, existing chain. How well it works is unknown.
Want one more example for the future?
USNI website has an article discussing the
class SSN replacement and a 200 nm range replacement torpedo. See if you can discern the kill chain in the following description of torpedo usage from the article. Virginia
“… to employ a 200-mile torpedo … Connor [ed. VAdm. Mike Connor, COMSUBLANT] said that while an attack boat like the Virginia or SSN(X) might launch a torpedo, the targeting data might come from another platform.
Those other platforms could include an aircraft like an unmanned aerial vehicle launched from the submarine or something like a Boeing P-8 Poseidon. In fact, the submarine might not even guide the weapon to its target in the terminal phase of the engagement, Connor said.”
OK, so kill chains are getting longer and more complex. What’s the point?
We stated in a previous post that
Complexity = Unreliability
Consider a kill chain as a series of events, each with its own probability of failure. It stands to reason that the more links in the chain, the greater the chance of one of them failing. If a single link in the chain fails, the entire chain fails. It turns out that there is a mathematical description of such a chain. Briefly, the probability of success for the entire chain is the multiplicative product of the probabilities of the individual events (links). If you didn’t follow that, don’t worry. What it means is you multiply the individual probabilities. For example, if there are two steps in a chain and each has a 95% probability of success, the total probability of success is,
.95 x .95 = .90 or 90%
In the example I offered at the start of the post, there are nine steps (links). If each step has a 98% chance of success, the total chance of success is only 83%.
Of course, each step is not uniform in its probability of success. Some will be very high and some will be less so. Regardless, the point is that the greater the number of steps (links) in the chain, the less likely the entire chain is to function correctly. Hence, again,
Complexity = Unreliability
The other aspect to a kill chain composed of high value units, as in this example, is that the units are tied up performing routine, mundane tasks. In the F-35 example, only the first one or two F-35s need stealth. After that, each F-35 is a colossal waste of resources. Of course, if the target is of sufficiently high value then the use of multiple F-35s performing nothing more than communications relay functions may well be worth it. However, for general surveillance the F-35s would mostly be wasted.
This doesn’t even begin to address the issue of maintenance as a function of complexity.
Back to the main point of unreliability as a function of complexity. We’ve looked at a simplistic example of a chain. Now, throw in the added complexity of the networks, nodes, displays, and software, all of which have to work correctly to receive the data, reduce it to an understandable tactical picture, and retransmit both the data/images and resulting actionable commands and we’ve added many more steps to the chain, each with their own failure rates.
Everything we’ve discussed so far has been idealized and the individual step (link) failure probabilities are those inherent to the step. Now layer on the effects of deliberate enemy disruption in the form of electronic countermeasures, jamming, false signals, etc. and many of the step failure probabilities increase significantly.
Lastly, top it off with natural disruptions such as weather effects, atmospheric ionization, solar flares, curvature of the earth, and whatnot and the failure probabilities further increase.
So, what is ComNavOps suggesting? Simply that we need to carefully balance complexity against reliability. Further, I’m suggesting that we’ve gone too far down the path of complexity.
Consider the F-35 targeting chain. Someone, on day one of conceptual design of the F-35, should have said, “Hey, we don’t want to set up a chain of multiple F-35s just to handle communications. Instead, let’s make a longer ranged communications capability an inherent part of the design so that a single F-35 can communicate with the controlling station. In fact, while we’re at it, why don’t we make sure that the F-35 can communicate directly with other platforms, like the Hornet or Hawkeye, without needing a conversion step.”
In combat, confusion will reign. The simpler our weapons and systems are, the more likely they are to work. It’s as simple as that.
See the target. Pull the trigger
USNI, “Navy Starting Work on New SSN(X) Nuclear Attack Submarine”, Dave Majumdar,
October 23, 2014,