The Buzz

No-Fly Zones: The Ultimate Guide

When conflict rears its ugly head around the world, there is usually a call for the United States to “do something.” One option that is frequently mentioned is the no-fly zone. The United States and its allies enjoy a significant advantage over most potential adversaries in the air. No-fly zones, therefore, are attractive due to the perceived lower cost and risk when compared to other options. Despite this, setting up a no-fly zone is anything but a “no brainer.” Depending on the circumstances, there may be steep costs and unseen risks. This short primer is intended to introduce readers to the way no-fly zones really work.

What is a No-Fly Zone?

A no-fly zone is airspace designated as “off limits” to flight-related activities. There needs to be an explicit policy concerning which actions that are prohibited in the zone, and this should be communicated clearly. In addition, there must be some form of punishment in response to violations. Typically, this involves friendly military aircraft intercepting violators and escorting them away, forcing them to land, or shooting them down.

Why Would We Establish a No-Fly Zone?

There are many reasons, but the most likely is to stop adversary aircraft from attacking or harming people on the ground—including friendly forces and civilians. In addition, establishing a no-fly zone can negate an adversary’s military advantage, put pressure on an adversary to make concessions, give hope and relief to people who have been attacked, weaken and demoralize an enemy air force, or serve as a prelude to invasion. Furthermore, a no-fly zone could be combined with other actions—such as a naval blockade or closing of a border—to stop the flow of goods and people into an area, further weakening an adversary.

When is a No-Fly Zone Likely to be Effective?

In most circumstances, a no-fly zone is effective only if the adversary has significant air forces. If the adversary’s air force is too strong, however, it will be very difficult to set up an effective no-fly zone. Therefore, a no-fly zone is most likely to be effective against an adversary whose air forces are substantial, but not too substantial.

Moreover, a no-fly zone can alter the balance of power on the ground. If one side relies heavily on airpower and the other does not, a no-fly zone can level the playing field and bolster forces that have been subjected to invasive observation or painful attacks. Conversely, if airpower is not an important factor, it’s unlikely that establishing a no-fly zone will do much (unless the mandate is extended to destroying ground targets).

What are the Requirements for a No-Fly Zone?

In the past, the United States has sought international approval when establishing a no-fly zone, usually from the United Nations Security Council. This provides a form of legitimacy. Without it, the legal basis for the no-fly zone will be questioned, as will our commitment to international norms.

The next requirement is to decide upon rules of engagementthe set of guidelines governing how the no-fly zone is enforced. These guidelines define who is and isn’t allowed to fly in the airspace and they prescribe a process for determining if someone is in violation. They must also address the sticky situations: Are civilian airplanes allowed to fly? What if a civilian airplane wanders into the airspace with no flight plan? What if the adversary uses civilian airliners as screens? What if the adversary loads civilians into a plane, then violates the no-fly zone? What if the adversary shoots at friendly airplanes enforcing the no-fly zone? The answers must be clear to those enforcing the policy. If the guidelines are too broad, our aircrew will have to interpret them while dealing with murky situations in real time. If the guidelines are too complex, they may have difficulty keeping them straight when reacting to a tense situation.

Enforcing a no-fly zone usually requires a large amount of military forces, including aircraft, the operators who fly them, and support personnel to protect and maintain them. Unless the no-fly zone is relatively small, it will take multiple flying units operating different kinds of aircraft. This includes air-to-air fighters that can intercept adversary aircraft. Specialized aircraft are also required for suppressing or destroying the enemy air defenses that could shoot our aircraft down. We need to be able to know when someone violates the no-fly zone, which usually involves a combination of airborne and ground-based radar. Air refueling aircraft are required if our bases are far away from the no-fly zone, and they also extend patrolling time for our aircraft. We will need to monitor the adversary and look for dangerous actions (such as setting up surface-to-air missiles), which requires Intelligence, Surveillance & Reconnaissance (ISR) aircraft. Since we will want to retrieve our aircrew should they be stranded due to mechanical failure or being shot down, we need combat rescue assets in the area.

In addition to these forces, we need bases to house and protect them, infrastructure to support them, and secure logistics lines for the flow of supplies and people. In the past, the United States has typically used a combination of land bases and aircraft carriers to support no-fly zone operations. It’s good to have several bases from which to fly, as a runway problem or bad weather could close a base and halt the operation.