Combat Rubber Raiding Craft
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The F470 Combat Rubber Raiding Craft (CRRC) is a specially fabricated inflatable rubber boat often used by the Navy SEALs and US Marines, among others. Though Zodiac International produces a large range of both inflatable and rigid-hulled boats, the name "Zodiac" has become synonymous with the CRRC.
The boat can be used for over-the-horizon transportation, inserting lightly-armed raiding parties or reconnaissance teams onto beaches, piers, offshore facilities and larger vessels. The CRRC can be inflated in minutes by foot pump, compressor or C02 tank and can be deployed from shore, a variety of vessels, and even aircraft-deployed as a so-called "rubber ducky" load. Its chief advantages are stealth, versatility, light weight, compact size when stowed, and the safety imparted by its hyper-buoyant nature, which gives it the ability to operate in relatively high seas for a craft of its size.
A total of 8 individual airtight chambers comprise the F470. The main hull or "gunnel" contains 5 intercommunicating chambers, which are separated by internal baffels and valves. This means that a single leak will not result in loss of pressure throughout the boat, and that air can be bleed between chambers to compensate for loss in one. Two additional chambers, located below the gunnel on either side and called "speed skags," provide cushioning for the boat's occupants and additional buoyancy in case of pressure loss in the hull. The final chamber is an inflatable keel tube which runs the length of the craft and gives the bottom of the hull a "V" shape, imparting directional stability and additional shock absorption. A wooden "transom" board at the stern provides a mounting point for the outboard engine(s) and a "thrustboard" at the bow keeps the hull from collapsing inward under power.
A ready-for-use Zodiac includes an outboard engine (two in some configurations); removable aluminum deckplates or roll-up slatted decking; paddles; a bow line for securing the docked boat and a "righting" line which is used to flip the boat in the event of capsizing. At the bow of the boat are storage bags for equipment (foot pumps, extra lines, etc.) and a special fuel bladder, which can be of either 6- or 18-gallon capacity and which feeds the engine via a flexible hose. Deflated and rolled up, the boat and all necessary equipment can easily fit into the bed of a small pickup. Most military CRRC's use a 55-horsepower two-stroke engine with a "pumpjet propulsor," which consists of a shrouded impeller. This design reduces the risk of serious injury to personnel in the water when compared to an open propeller. It also reduces the chance of the propulsion system sustaining catastrophic damage in shallow water.
A specially-trained "coxswain" sits at the stern of the boat and controls it via the tiller arm, attached to an outboard engine. The coxswain is considered the commander of the craft and is ultimately responsible for its operation, regardless of whether a senior-ranking individual is on board. Across from him sits the assistant coxswain, who relays hand signals from other boats and aids the coxswain in controlling the craft. The remaining passengers (six raiders plus the two coxswains make up a full team) normally lay on and straddle the gunnel, keeping a low sillhouette to help avoid detection and leaving room on the deck for weapons, equipment and (if necessary) additional fuel bladders.
Because the CRRC offers no ballistic protection to its occupants and is itself highly vulnerable to small-arms fire, operations involving it almost always take place at night and depend on the elements of stealth and surprise. During a textbook beach raid, for example, the raid craft stop at a point either 500 or 1,000 meters from the landing site and deploy "scout swimmers," who fin to the landing site, marking obstacles and eliminating sentries as they conduct reconnaissance. Only after the scout swimmers have secured the beach and given a pre-arranged signal do the boats creep in at idle, rendering them silent against surf noise. Upon landing (and depending on the type of operation) the boat teams will either face the boats toward the sea for a quick extraction or "cache" (hide) them. Again depending on the operation, the cache can vary from merely concealing the boats in dirt and vegetation to deflating and completely burying them. When stealth is either not required or has already been compromised, the F470 may conduct a "hard landing" wherein the coxswain beaches the craft at full throttle--allowing the team to instantly disembark and fight.
Zodiac boats are not limited to military use. Their versatility, safety and ease of use has made them popular choices for law enforcement, search and rescue, and private hobbyists.
[edit] Specifications
- Length 4.7 m (15'5")
- Width 1.9 m (6'3")
- Empty weight 146 kg (322 lb)
- Max engine weight 110 kg (243 lb)
- Max passengers: 10
- Max payload (including fuel): 1,250 kg (2,756 lb)
- Max range: varies depending on fuel load and payload
