The U.S. Air Force and Navy have developed a cheap alternative to the torpedo called Quicksink. This weapon uses a modified version of the JDAM kits that turn an inexpensive unguided (“dumb”) bomb into a GPS guided bomb. Quicksink, like regular guided bombs can be released up to 24 kilometers from the target. The GPS coordinates can be programmed into the JDAM kit before releasing the bomb or altered after launch from the aircraft. When the Quicksink bomb gets close to the target, it goes underwater and glides to the nearby ship, detonating against the hull like a torpedo. The U.S. conducted a test against a large cargo ship scheduled for scrapping that was towed into position on a maritime test range. The Quicksink bomb performed as intended and hit the ship underwater, blowing it in half like a heavy torpedo, costing millions of dollars, would. The ship sank within minutes.
Quicksink is not intended for use against warships equipped with air defense systems, or commercial ships escorted by such warships. Even in wartime a lot of large cargo ships travel alone and Quicksink would be a more efficient and cheaper alternative than using torpedoes. Quicksink is resistant to GPS jammers because its alternative INS (Inertial Navigation System) is unjammable although less accurate. When the target is a large commercial ship moving at its normal slow cruising speed (to reduce fuel costs) Quicksink would still work.
The warplanes carrying Quicksink also carry targeting pods that enable pilots to see, in great detail, what's happening on the surface, even when the aircraft is flying at 6.8 kilometers (20,000 feet) altitude. For example, the pod users can tell if someone down there is dressed as a man or a woman, or is carrying a weapon. With much larger naval targets, identification is a lot easier. Any aircraft, including heavy bombers, can use the pods for attacking ships at sea. In 2011 a B-1B successfully used laser guided JDAM bombs against moving naval targets. These tests involved the B-1B using its Sniper targeting pod to put the laser beam on the target. The JDAMs homed on the laser light reflecting off the moving target ships. The laser guided bombs are more expensive than Quicksink and do not attack underwater like a torpedo.
Targets would be enemy shipping, especially in the early stages of a war. Quicksink could also be useful in some wartime situations, like a Chinese amphibious attack on Taiwan. The Chinese plan to use dozens of large R0/Ro (Roll on/Roll off) ships that could put hundreds of armored and unarmored vehicles on certain beaches or any dock. These ships are unarmed and American or Taiwanese aircraft could launch several Quicksinks at each target, using accompanying EW (Electronic warfare) or SEAD (Suppression of Enemy Air Defenses) aircraft to suppress anti-aircraft air defenses long enough for the Quicksinks to be launched and reach their targets. At the very least, Quicksink forces China to reconsider their current invasion plans. A Quicksink kit with small wings would provide an even longer (over 60 kilometers) glide range for Quicksink.
With Quicksink available China has to worry about their commercial shipping in general, especially in the early stages of a war when many of those ships operate independently and vulnerable to Quicksink.
Quicksink builds on the American experience with air dropped naval mines. These were used since World War II, with each generation of air-deliver mines becoming more capable. In 2018 the U.S. successfully used a JDAM glide and satellite navigation kit to deliver a 2,000-pound (909 kg) Quickstrike naval mine to a location over sixty kilometers from a B-52 bomber, that can carry dozens of these mines. For this test Quickstrike had no explosives, just inert material to maintain the proper weight. The Quickstrike had its naval mine sensors and other electronics plus a locator device. That enabled a ship to locate and recover the Quickstrike, which was found to be functioning properly.
These tests began in 2015, using a 500-pound (228 kg) Quickstrike and later a 1,000-pound (456 kg) Quickstrike. Now the Air Force or Navy can deliver all three sizes of these Quickstrike ER (extended range) mines using JDAM.
The original Mk-62 Quickstrike was basically a 500-pound bomb, with a sensor package attached to the rear. There were three different sensor packages, each providing a different set of sensors to detonate the mine. The Mk-62 is a "bottom mine," which is dropped in shallow water, and then detects a ship passing above using pressure (of the ship on the water), magnetism (of the metal in the ship’s hull), or vibration. The sensor also comes with a computer, to enable the mine to follow certain instructions, like only detonating for ships that meet certain criteria. Think of Quickstrike as the ultimate underwater weapon, being relatively inexpensive, autonomous and relentless in carrying out its mission.
One drawback with the Quickstrike is that the aircraft delivering it had to drop the mines at an altitude of 300 meters or less while moving at 500-600 kilometers an hour. The mines are usually dropped in known shipping lanes, especially those that serve as approaches to a major port. World War II air dropped mines proved devastating to Japanese shipping. Same thing with their use against North Vietnam during the Vietnam War. Any bomber aircraft that can go in low and slow can deliver Quickstrike. The F-35, F-18, B-2, B-1B, P-8 and P-3C can also deliver naval mines. The U.S. air force and navy revived regular Quickstrike bombing exercises nearly two decades ago and publicized them to send a message to North Korea, Iran and China about how quickly their seaborne lifelines could be cut. China responded by stationing air defense systems to cover the shallow water sea lanes that Quickstrike could be used in.
The United States has since developed Quickstrike ER. The current JDAM smart bomb kit comes with wings that enable the bomb to glide up to 70 kilometers thus avoiding many enemy air defenses. It also means you don’t have to risk your nuclear subs for the delivery of these mines. Subs have long been an effective way to plant mines in enemy waters. The JDAM approach does not eliminate all risk from anti-aircraft systems. China and Russia have modern S-300 systems with ranges of over 200 kilometers. But the farther away the attacking aircraft are the less they are at risk. That’s because American aircraft go into combat with EW (electronic warfare aircraft) and EW devices on all aircraft. That provides a lot of protection but it is not 100 percent and the less time you spend in the danger zone the less risk you are exposed to.
More improvements are planned for Quickstrike. The next step is to test longer range glide bombs like JASSM, with a range of up to 900 kilometers. The original JDAM bomb kit (added to 500, 1,000, and 2,000-pound bombs), cost $26,000 each. The longer range (120 kilometers) JSOW (JDAM with larger wings and more powerful guidance system), cost $460,000 each. The even longer range JASSM cost $500,000 (the 400 kilometers version) to $930,000 (the 900-kilometer JASSM ER) each. Air defense systems can detect JDAM, JSOW and JASSM but with some difficulty because these glide bombs are small, low and slow moving.
China has not developed systems similar to Quickstrike or Quicksink in part because Western nations have more commercial ships operating over a wider area than China, which only has one coastline that is much smaller than the combined coastline of Western nations.