V1 Flying Bomb
The Fi 103 (better known as the V-1) is an unpiloted cruise missile, nicknamed the "Buzz Bomb" or "Doodlebug" by the Allies.
The Fi 103, later termed the Vergeltungswaffe 1 ("Retaliation Weapon 1") was designed as part of the German program of producing "wonder weapons" to try and win the war by raining destruction on England. Testing began in the fall of 1942, with the first strike against London launched on June 13th, 1944 following the Normandy invasion. The concept was simple - a cheap pulse-jet engine and plywood wings fitted to a sheet-steel fuselage containing an inertial guidance system, fuel, and an 850-kg warhead. It took 350 hours of labor to produce an Fi 103, 120 of which was taken up with a guidance system that used a compass and inertial gyros to keep the weapon on a preset course. A windvane counter monitored the distance covered; once reached the elevator controls were severed and the rudder set to neutral. On early models this also cut off the fuel flow to the engine, resulting in onlookers below hearing the characteristic buzzing noise cut off shortly before the terminal dive.
Fi 103s were launched either from fixed launch rails on the ground or air-launched from specially modified Heinkel He 111 bombers at night over the North Sea. Both methods had their drawbacks; fixed sites were the subject of continued air attacks and fell to advancing Allied troops after Normandy, while bombers were vulnerable to Allied nightfighters. After launch, the missile still averaged only a 1 in 4 hit rate; problems with fuel pressure regulators led the cruise altitude to be cut from the original 9000 feet to 2000-3000, which made them vulnerable to interception by Allied 40mm anti-aircraft guns. Aircraft interception, guidance failures, and mechanical problems also downed Fi 103s short of the target. Nevertheless, 2,419 struck targets in England while 2,448 hit Antwerp, Belgium following the port's capture by the Allies. The threat of the V-1 was taken seriously by British forces; large numbers of anti-aircraft batteries, special interceptor squadrons including the first operational RAF jet fighters (the Gloster Meteor), elaborate intelligence disinformation campaigns, and a concentrated bombing offensive against V-1 production and launching sites were all brought to bear.
Although primitive, the Fi 103 quickly inspired Allied copies (the nearly identical US JB-2 "Doodlebug" was planned for use in the canceled invasion of Japan, while the Soviets overran a test range in Poland and produced their own 10Kh prototype) and prior to the fielding of ICBMs larger, faster, and nuclear-armed descendants of the V-1 served as deterrent weapons in the US and USSR arsenals. With the end of the Cold War the American Tomahawk has demonstrated the realized capability of the cruise missile; equipped with a modern GPS system it can hit selected buildings after a 1000-mile flight.
The Fi 103 is a cheap and powerful alternative to fighter-bomber strikes, allowing a German player to rain high-explosive missiles down on an opposing base. However, the flying bomb is vulnerable to concentrated anti-aircraft fire and can be knocked down by fast interceptors such as the P-51D or Spitfire. Its accuracy leaves much to be desired; if one's goal is pinpoint destruction of yards, troop and vehicle concentrations, or gun emplacements as opposed to random mayhem a fighter-bomber strike is a better if more expensive option.
The low cost and lack of warning makes this a gret end game bombing mechanism, as no fighters can be deployed to stop them and ground AA need to be made in bulk to have any effect.
On the other hand, V1's need to be made in bulk as well, but destroying high-value targets, such as upgraded tank yards will always be cost-effective, as well as storage locations.