Op-ed | The move from survivability to resilience


This op-ed originally appeared in the April 23, 2018 issue of SpaceNews magazine.

The U.S. has become truly dependent on space based capabilities. The missions performed by space systems support everyday civilian life and our critical warfighting capabilities. These missions need to survive both intentional attacks (reversible and non-reversible) and unintentional threats such as debris and unintentional jamming. There is not much we can do against an accident due to orbital debris, or against a determined adversary, who given today’s technology can eliminate nodes of oursystems. For the determined adversary, the more expensive the nodes (fat, juicy targets) the better, both in terms of cost tradeoffs and ability to inflict significant combat effects to deny, disrupt, degrade, manipulate and potentially destroy.

Therefore, the U.S. is clearly pursuing “resilience” of these critical space-based missions. We are also at an inflection point on the next generation of space systems. If we do not make this change now, it will be 10 to 20 years before we have another opportunity. Delaying this change in the name of continuity could be a disaster. Additionally, “resilience” is not merely a new term de jour. It is a real change in focus and strategy. It is not a recast of “survivability”. The definitions of these two key terms are:

  • Survivability is the ability of a node, satellite or payload to survive an attack and continue performing as an independent stand-alone element of a constellation.
  • Resiliency is the ability of the mission to endure the loss of one or more nodes, satellites or ground system elements — perhaps degraded but still operational. The mission may continue to function by use of augmented capabilities available from sources other than the original system or mission configuration.

Survivability drives a.) hardening (both lifetime and prompt dose), b.) maneuverability, c.) active defense, d.) passive defense, e.) anti-jam, f.) cyber hardening/resistance, and f.) laser tolerance to dazzling and destructive attacks.

Resilience drives a) disaggregated systems, b) affordability to allow sparing and system redundancy (proliferation), c) interoperability with other missions/systems, (diversity) d) responsive launch/rapid turn-around times, e) density of the constellation, (proliferation) f) rapid technology insertion, and g) reconstitution.

It appears that in response to the desire for resiliency, some have interpreted this to mean even more survivability, and more stringent survivability criteria. The problem is that this thinking results in real resilience strategies being ignored. If the pure survivability requirements for each node or satellite are stringent, these requirements will negate a key objective of resilience by increasing development schedule and costs. Further, pure survivability solutions may prove less effective against an attack than an approach-based resilience.

While it is true that survivability is an element of resilience (in Pentagon resilience taxonomy it’s part of the “protection” category of the six resilience elements) the goal is not to maximize survivability, it is to maximize resilience. In fact, I believe survivability is included as part of resilience so that survivability (its benefits, cost and schedule impacts) can be assessed in the larger picture of affordability and mission resilience. If making a node survivable costs a lot of money, increases the schedule to get systems on orbit, and can be taken out by a determined adversary, increased survivability acts counter to resiliency.

Making systems overly expensive by overemphasizing survivability counters the ability to produce systems in an affordable way so as to make them resilient. Nuclear hardening against prompt dose is not insurmountable, but it eliminates the use of commercial buses since the manufacturers will not add the cost of prompt dose hardening to their entire bus family. Once you make prompt dose an issue, you eliminate the cost savings of using commercial off-the-shelf products and significantly reduce competition. You also effectively end any effort to provide mission resiliency and to find more affordable and effective solutions to the problem. There needs to be a discussion at the senior leader level as to the right direction. If we want to exploit the ability to lower cost, risk, and schedule, and proliferate commercial buses, we need to offset any issue of prompt dose survivability.

Obviously, a balance is needed here; ignoring survivability is not wise, but it should not be confused with resilience and must be traded in the total resilience equation, with mission resilience being the priority. The goal is to assure mission continuity (at least at some level) regardless of the loss of nodes or satellites, and to do that primarily with resilience. Intelligent use of resilience, employing selective use of survivability (especially against non-kinetic effects) will prevent unduly driving schedules or significantly increasing costs.

In addition to being conscious of making our missions resilient, we also need to be aware that long life (greater than seven years) is the enemy of resilience, affordability and the short schedules necessary for rapid technology insertion.

While mission performance and accomplishment will always be No. 1, “resiliency” has become a strong 1A goal for any space system. Additionally, we cannot lose site of the other goals. The next goal is affordability, which includes shorter development schedules. Proliferation is No. 3 and rapid technology insertion is No. 4. Disaggregation, sparing, rapid reconstitution, and responsive launch also remain key attributes for our future space systems.

Tom “Tav” Taverney is a retired Air Force major general and former vice commander of Air Force Space Command. He has served on SMC and Space Command advisory boards, and has supported acquisition and launch system reviews.