Air-to-surface missile

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An A-10 pilot inspects an AGM-65G

Air-to-surface missile is the name for self-propelled ammunition of short to medium range , which is used by combat aircraft and attack helicopters against ground and sea targets. A distinction can be made between guided missiles , unguided rockets and air-launched ballistic missiles (ALBM).

history

The first air-to-surface missiles were developed before the Second World War , for example the Soviet RS-82 and RS-132. In Germany they were a further development of missiles that were initially developed for use against aircraft. Examples are the Panzerblitz II and III, derivatives of the R4M "Orkan" air-to-air missile .

Another line of development emerges from equipping glide bombs with controls. In the Second World War, for example, the German Air Force used the Henschel Hs 293 , a range-increased aerial bomb with manual controls, against ships.

commitment

An AGM-65D shot down from an F-16C

Unguided air-to-surface missiles require an approach to the target in order to minimize dispersion .

Guided missiles, on the other hand, can be fired from a relatively large distance due to the usually more powerful drive and controls. The carrier platform can thus remain outside the enemy defensive fire and still hit targets with high precision.

construction

Launch device with Hydra 70 on an AH-1 Cobra
Clearly visible: HARM launch device (between external load carrier and rocket) and control surfaces arranged in a cross

An unguided air-to-ground missile is composed of the warhead and the rocket motor. Guided missiles consist of a warhead, sensor, guidance system (usually with control flaps) and drive. A starter device is required for attachment to the aircraft's external load carriers .

sensor

There are two types of infrared seeker heads: the first, the seeker head detects and follows the heat emitted by the target (IR). In the second, the pilot looks at the thermal image of the target on a screen in the cockpit and activates the seeker head; Called IIR (Imaging Infrared).
A laser beam is used to mark a target, the seeker captures the reflections and controls the missile accordingly.
Also called active radar in English ; here the missile itself sends out a radar signal, the reflections of which it receives and thus pursues the target.
  • Semi-active radar:
A semi-active radar or semi-active radar means that the target is irradiated with radar from the carrier aircraft, while the rocket itself only has a radar receiver and thus absorbs the emissions.
A targeting method in which a missile equipped with it detects and targets enemy radar emissions without emitting radar emissions itself.
  • Optical:
A missile aiming system in which an electro-optical viewfinder (video) scans a predetermined area. As soon as a potential target is discovered, the shooter can recognize it via the television picture in the cockpit and steer the missile towards it.
An American navigation system that consists of more than 24 satellites. This allows a rocket equipped with it to hit a certain coordinate with great precision in any weather and time of day anywhere on earth.
is the Russian counterpart to the American GPS.
A targeting system that measures the missile's acceleration in all three axes to determine its position and acceleration. It is insensitive to electronic countermeasures .
  • TERCOM (Terrain-Contour-Matching) and DSMAC (Digital Scene Matching Area Correlation):
TERCOM is a missile navigation system that uses a contour map of the terrain over which the missile is flying. TERCOM "sees" the terrain with the help of a radar system, over which it flies and compares it to a stored map. This allows it to fly much lower and is more accurate than a missile that is only equipped with inertial navigation.
The DSMAC is the improved version of the TERCOM. It is a navigation system that, during flight, compares the images of the area with preloaded satellite images that the missile carries in its memory (see digital terrain model ).
  • TAINS (Tercom-Aided Inertial Navigation System):
The TAINS uses the TERCOM and INS inertial navigation systems. Both systems complement each other with their data in order to determine the position even more precisely.
  • Precision Terrain Aided Navigation (PTAN):
A missile navigation system currently under development that uses a global digital database of radar maps.

drive

AGM-142 Have Nap (graphic)
is the most commonly used propulsion system in air-to-surface missiles. This is mainly due to the fact that the solid-fuel motor is very simple. The main disadvantage is the lower efficiency and that neither the performance (thrust) nor the burning time can be influenced.
The advantage over rockets with solid-fuel motors is that they switch on and off and allow changes in the thrust. The disadvantage, however, is the higher expenditure for storage and processing as well as for the engine.
A jet engine (also jet engine or jet turbine , English turbojet or turbofan ) is an engine that works on the principle of the recoil drive . The thrust is carried by a gas jet . Jet engines suck in the ambient air and eject it again as a drive jet. Because the oxygen required for combustion is taken from the sucked in air, we also speak of air-breathing engines.
The turbofan is a further development of the turbojet with at least two shafts, partially separate air flows and a greatly enlarged first compressor stage . Because of the second air flow, one speaks of a twin- flow jet engine or a turbofan engine , while Russian manufacturers speak of a bypass engine. The efficiency of a turbofan is higher than that of a turbojet.
This air-breathing engine dispenses with moving parts such as turbines, but achieves lower levels of efficiency than a turbojet and requires a booster to start .
This is the high-speed version of the Ramjet for speeds from Mach 3. Missiles with this drive are in development. In 2012/2013, for example, the US Air Force tested the experimental Boeing X-51 , which was launched by a Boeing B-52 bomber.

See also

literature

  • Jeremy Flack: NATO Air Forces guided and dropped weapons. Motorbuch Verlag, ISBN 3-613-02525-6 .