What’s the Right Way to Board a Hostile Ship?

The Israeli military has admitted that failures of both planning and execution led to the botched raid on a flotilla of pro-Palestinian activists last weekend, which left nine dead and has erupted into an international scandal. With two more activist ships on the way, a top Israeli Navy commander has promised to use more aggressive force next time and prepare "as if it was a war." So what’s the right way to seize a ship?

It all depends on the situation. Thanks to both the growing problem of international piracy and the enforcement of new arms embargoes, Visit, Board, Search, and Seizure (VBSS) tactics have become an increasingly important part of naval operations. In the United States, special units of the Coast Guard, Navy, and Naval Special Forces are all trained in VBSS.

The first step in any boarding operation is to figure out what you’re dealing with. The naval ship or helicopter that encounters a suspicious vessel will contact the suspicious vessel and attempt to ascertain whether a "compliant" or "noncompliant" boarding is required. Given what was known about the crew and political aims of those on board the Mavi Marmara, the Israeli commandoes should probably have assumed non-compliance.

In the event of a noncompliant boarding, there are two options for how you get on the ship — side boarding from a small boat or rappelling down from a helicopter. The U.S. Coast Guard, which mainly interdicts small ships suspected of carrying drugs or illegal immigrants, almost always uses side boardings. Large ships, however, like the 4,000-ton Mavi Marmara, are relatively easy to defend from invaders scaling up the sides, as Greenpeace protesters and Somali pirates have learned. In the U.S. Navy, only Special Forces units like the SEALs do noncompliant boardings of large ships.

Helicopter insertions have their own challenges. Most experts say they should be done when troops can rappel down quickly and when there’s a clear landing area for boarders to establish their position. The Israeli military‘s video of the Mavi Marmara raid shows that neither of these conditions were met. In typical helicopter VBSS operations, the boarders land near the ship’s pilot house, where they can quickly take control of the vessel. The Israeli team landed on the open deck instead.

The size of the boarding team depends of the size and crew of the ship being boarded, but at a minimum, there should be enough boarders to guard the crew in one section of the ship while sweeper teams search for contraband, weapons, or hidden crewmembers.

Unlike the Israeli commandos, some of whom carried only paintball guns onto the deck of the Mavi Marmara, U.S. Coast Guard officers carry at least a handgun onto every boarding, even compliant ones.

If a safe boarding is not possible, there are other options for preventing a ship from delivering contraband or breaching an embargo. The navy vessel can attempt to force a ship to turn around by firing a warning shot, an internationally recognized tactic. With the right size advantage, a naval vessel can "shoulder" a civilian ship — literally push it off course. (This probably isn’t an option for the Israeli Navy, which doesn’t have any ships larger than a corvette.) Or it can attempt to disable the ship’s propeller or rudder. The simplest way to do this is by firing on the ship, but the recent piracy boom has spawned a cottage industry of new, non-lethal propeller-fouling technologies. 

The bottom line is that Israel seems to have erred in assuming a compliant  boarding, choosing a landing site, and inadequately arming the boarding team. It’s unlikely they will make the same mistakes twice, but even with the best planning, carrying out a noncompliant boarding with the entire world watching on TV is a scenario that isn’t covered in any naval manual.

Thanks to Lt. Paul St. Pierre of the U.S. Coast Guard, , Cdr. Bryan McGrath of the U.S. Navy (Ret.), Cdr. James Kraska, chair of operational law at the U.S. Naval War College, and Edward Luttwak, senior associate at the Center for Strategic and International Studies.

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