|You are in: Americas|
Sunday, 3 March, 2002, 12:38 GMT
Guide to military strength
A huge array of military options is available to the US in its campaign against Osama Bin Laden and his allies in Afghanistan.
The United States has aircraft which can fly thousands of miles to drop a large weight of bombs or launch other weapons.
It has a crew of five and can carry up to 20 cruise missiles.
Seven of the aircraft flew from Barksdale Air Force Base in Louisiana at the start of the Gulf War to fire their missiles at Baghdad - the longest known combat sorties in history, taking 35 hours to cover more than 14,000 miles.
Washington has sent B-52s to the Gulf area. They are routinely deployed on Diego Garcia, a British Territory in the Indian Ocean which has major military facilities.
It has a crew of four and can fly at speeds in excess of 900mph.
Originally intended to carry nuclear weapons to penetrate Soviet defences, the swing-wing B-1 was first used in combat against Iraq during Operation Desert Storm.
Some of its sophisticated systems have shown problems though it operated reliably during the Kosovo conflict.
The third type of long-range American bomber is the two-crew B-2 Spirit - at some $2.2bn each it is the world's most costly aircraft.
Stealth is a combination of design, coverings to reduce reflection or radar "signature", and other techniques such as masking the heat from engines. Stealth aircraft are harder to spot but not invisible.
B-2s from Whiteman Air Force Base in Missouri, Diego Garcia and Guam can cover the whole world with only one mid-air refuelling.
The first combat missions were in 1999 when B-2s from Missouri struck at Serbia and Kosovo.
But there have been problems with the aircraft's radar-absorbing skin, which can be damaged by moisture and bad weather.
It is a relatively small, single-seat aircraft typically used for precision attacks against difficult targets, especially early on in an air campaign.
F-117As flew more than a third of the bombing missions on the first day of the Gulf War although there were only 36 of them among 1,900 allied combat aircraft.
They were used again in Kosovo, where one was brought down by Serbian air defences.
Although not capable of operating from aircraft carriers, they can refuel in flight from tanker aircraft to give them an unlimited range.
Both stealth aircraft are relatively slow - achieving "high subsonic" speeds.
The US aircraft carrier Theodore Roosevelt and its battle group was heading for a scheduled six-month deployment to the Mediterranean.
There are also two attack submarines, the USS Hartford and the USS Springfield, which can fire Tomahawk cruise missiles.
A marine expeditionary unit of this sort of strength is the basic building block for US amphibious operations.
It includes ground troops with supporting artillery, amphibious assault vehicles and light armour, plus transport and attack helicopters and perhaps AV-8B Harrier jet fighter-bombers, capable of taking off and landing vertically.
The US Navy has a carrier battle group in the Gulf - centred on the USS Carl Vinson - and a second, with the USS Enterprise, in the Arabian Sea.
The USS Kitty Hawk, normally the only US aircraft carrier stationed in the western Pacific, has joined it.
Reports say its usual complement of aircraft have been removed to make way for special forces.
On board the aircraft carriers there are typically 70-80 planes for defence, attack, refuelling in flight, jamming enemy communications and radars, and for airborne surveillance and control.
Airborne warning and control for an area of military operations is provided by special AWACS planes carrying big, rotating radar discs.
Used in the Gulf War and in Bosnia, this combined command centre and radar station has a flight crew of four and between 13 and 19 specialist operators. It can go for more than eight hours without refuelling.
A smaller version, operated from US Navy aircraft carriers, is the E-2C Hawkeye, a two-engined turboprop.
A different Boeing 707 variant, the E-8C JStars, has a canoe-shaped radar dome under its nose to locate, classify and track ground targets in all weathers.
Yet another version, the RC-135V/W Rivet Joint, is a surveillance aircraft, widely used during Desert Storm and over Bosnia to gather images and electronic signals.
The RAF Nimrod R1, which fulfils a similar role, has a crew of 12 - two flight crew and 10 to operate the specialist eavesdropping equipment.
The U-2 spy plane is a relic of the Cold War but still in use to give day or night, all-weather, high-altitude surveillance.
All military forces are increasingly using small, pilot-less aircraft known as UAVs - unmanned aerial vehicles - to feed back video or still images of target areas.
Typically these fly very slowly, less than 140mph (225kph), but can loiter over an area for many hours.
Their slow speed makes them vulnerable: One American UAV - thought to be an RQ-1 Predatoror earlier special forces version, the Gnat-XP, made by the same firm - was lost over Afghanistan on 22 September. Two others were shot down by the Iraqis in the summer of 2001.
Nato lost more than 20 unmanned surveillance aircraft of various types during 78 days of operation in Kosovo.
These sophisticated flying bombs typically spearhead any American attack.
The Boeing AGM-86 conventional air-launched cruise missile has a turbofan jet engine that propels it at subsonic speeds of about 550mph (880 km/h).
The US Navy and the Royal Navy use the similar but slightly smaller and slower Raytheon BGM-109 Tomahawk cruise missile, fired from ships or submarines.
The "conventional" in the name refers to the fact that it carries high explosives rather than a nuclear warhead.
It can travel up to about 690 miles (1,100km) using its own inertial navigation and global positioning systems to find its way.
It is less than 21ft (6.4m) long and can fly a low, zig-zag route making it hard to detect by enemy radar.
The GPS system uses a global network of satellites to provide accurate navigational information for sailors, hill walkers, and even drivers. Hand-held GPS receivers are widely available.
The weapon is programmed with the target location and can steer itself towards the intended target by constant reference to the satellites.
GPS-equipped cruise missiles are highly accurate although their Gulf War performance was not as good as believed at the time.
GPS-equipped weapons do not attack targets as such, but target co-ordinates: They are only as accurate as the information about the intended target's precise location.
The Americans have a number of one and two-seat strike jets apart from the long-range and stealth bombers.
The F-15E Strike Eagle is the dual-seat ground attack version of the United States Air Force's main fighter.
In the Gulf War, F-15Es flew mainly at night to hit Scud missile launchers and artillery sites.
The F-16 Fighting Falcon fighter-bomber is the backbone of the US Air Force, built in a consortium with four other Nato countries.
The F/A-18 Hornet is the US Navy's main carrier-borne strike aircraft.
It was designed from the outset to be capable of multiple roles - as a fighter or in ground attack/reconnaissance.
There are single-seat and two-seat versions.
The two-seat F-14 Tomcat - the Tom Cruise Top Gun plane - is used primarily for air defence over the carrier fleet.
But it also has the LANTIRN targeting system to drop laser-guided bombs for precision strikes on ground targets.
F-14s using a different equipment pod also fly reconnaissance missions.
It is capable of carrying a variety of bombs and missiles, and has a devastating 30mm Gatling gun in its nose which can fire 3,900 rounds a minute.
It flies slowly - little more than 400mph (640kph) - but is highly manoeuvrable and is designed to give close support to ground forces.
A severe limitation of these one or two-man planes is their range.
The "combat radius" of the latest E/F Super Hornet versions of the F/A-18, for instance, is just 450 miles (720kms) with four 1,000lb bombs, the standard two Sidewinder missiles for self-defence, navigation and targeting equipment and two 1,818 litre (480 US gallon) external tanks.
For this reason it is normal for pilots to refuel their planes in the air by connecting to a boom lowered by a tanker aircraft.
So, crucial to any American military deployment are KC-10 Extender tankers, derived from the DC-10 airliner, or KC-135 Stratotankers, the mainstay of the air-to-air refuelling fleet.
There are two sorts: Steered onto a target by attacking aircraft, or guiding themselves by homing in on a target - for example, signals emitting from a radar station - or on a laser light shone onto it.
This lets the attacking crew see the target from the weapon, so they can lock on to it before firing or, in some types, steer the rocket-powered missile onto it.
Some allow one plane to fire the missile and another to guide it.
The new JSOW (Joint Standoff Weapon) looks like a small cruise missile without an engine. It can be fired a significant distance from its target - 15 to 50 miles - then glides down guided by GPS signals.
An attack by US jets against Iraqi targets in February 2001 showed there were problems, perhaps in the computer software. Many of the JSOWs missed their targets by significant distances.
While highly effective in the Gulf War, the poor weather during the early stages of the Kosovo air campaign greatly limited the use of laser-guided weapons because the faint, reflected laser light can easily be obscured.
A way around this is the JDAM project - in effect a kit which can be attached to conventional bombs, giving them a GPS system and guidance mechanism.
GBU-28 'bunker busting' bombs
GBU-28 'Bunker Buster' bombs, carried by B-2 Stealth bombers and F-15 fighters, were developed during the 1991 Gulf War to penetrate and destroy underground Iraqi command and control facilities.
Over the last decade the bombs have been refined and developed, and are now an integral part of the US arsenal.
The laser-guided bombs carry a 4,400lb penetrating warhead, and can tear through more than 20ft of concrete, or 100ft of earth, before detonating.
Sometimes called iron bombs - the vast bulk of the weaponry dropped during both the Gulf War and the operations over Kosovo and Serbia were traditional free-fall bombs.
Iron bombs would tend to be used against military formations in the open, not targets in built-up areas.
These are highly controversial weapons consisting of a canister containing a large number of sub-munitions or bomblets.
These can be shot out at a pre-determined altitude as the weapon falls, covering a large area.
Human right and arms control groups want them banned due to their indiscriminate nature and lingering effects.
The military see them as a highly effective way of keeping troops and vehicles out of an area.
For example, one sort contains submunitions which in turn each contain armour-penetrating rockets with infrared sensors. These look for a heat source as they fall, then attack it.
If no target is detected after a set period of time, they go off anyway to try to damage vehicles and people.
These weapons are capable of penetrating deep underground to reach hidden command bunkers or caves.
The bomb, once detonated, spreads vaporised fuel through the air, then ignites it. This produces a fireball, and a rapidly-expanding blast wave many times greater than that from conventional explosives.
This in turn creates a vacuum - hence their other name, vacuum weapons. The effects are similar to those from a small nuclear weapon, without the radiation.
"It works as a combination of a shock wave and a fuel explosion," said Navy Lieutenant Commander Matthew Klee, a spokesman for the Central Command.
"The first explosion spreads flammable aerosols through the underground complex. The second ignites the fuel."
A similar type of bomb is reported to have been used by the Russian army against separatists in the breakaway republic of Chechnya.
A number of warheads, such as shells from an A-10's Gatling gun, have tips of depleted uranium - the substance left over after natural uranium has been enriched for nuclear weapons or reactor fuel.
It is very dense - 1.7 times denser than lead - and is highly valued militarily for its "self-sharpening" ability to punch through armour.
When it does, it produces dust which is chemically poisonous and also radioactive.
Gulf and Kosovo veterans believe this has made them ill.
Getting troops and machinery into the region involves a range of aircraft that can carry especially heavy loads.
The latest US transport aircraft, with global range, is the C-17 Globemaster. It has four turbofan engines and can carry a load of 170,000 lbs (77,000kgs).
In spite of its size it is able to operate from poorly-prepared airfields.
It is used for a variety of missions from carrying troops and equipment to evacuating casualties.
There is a special operations version with removable fuel tanks, two machine guns, an air-to-air refuelling probe and an external hoist.
The HH-60G Pave Hawk is a highly modified US Air Force version which can operate day or night and in poor weather.
The bigger MH-53J Pave Low is the most sophisticated helicopter operated by the United States Air Force - or probably any forces.
The AH-64 Apache is the US Army's main attack helicopter - it was an Apache which fired the first shots in the ground war to liberate Kuwait from Iraqi occupation. It has guns, rockets and missiles.
The latest Longbow version has a sophisticated targeting system that can scan an area, detect more than 100 targets, decide which are the most dangerous and share the information with other aircraft.
The entire fleet was grounded last year for inspections, after a crash was traced to a problem in the tail rotor assembly.
The Marines' lighter attack helicopter is the AH-1W Super Cobra, also used to great effect in the Gulf War.
It is most likely that special forces would be first on the ground in any military action in Afghanistan - some reports say they are there already.
Delta Force is the specialist US Army team used for counter-terrorism operations outside the United States.
This highly secretive unit is thought to have been involved in the abortive mission to rescue US hostages in Iran in November 1979.
Delta Force was modelled on the SAS (Special Air Service) - an elite British special forces unit with recent operational experience in both the Gulf and the Balkans.
Widely seen as among the most professional and experienced of such formations, the active service SAS regiment is divided into so-called Sabre Squadrons, each of which in turn is divided into a number of troops.
It is a version of the four-engine turbo-prop C-130 Hercules transport aircraft and as such is slow, flying at less than 300mph, but has a range of around 2,000 miles without needing to refuel and can loiter over a combat area for some time.
The latest U model, known as Spooky II, has three big guns projecting from the left side of the fuselage: a 25mm Gatling gun that can fire up to 1,800 rounds per minute, and 40mm and 105mm cannons.
It uses television, infra-red and radar sensors to locate ground targets, even at night. The AC-130U has 13 crew.
The BBC is not responsible for the content of external internet sites
Top Americas stories now:
Links to more Americas stories are at the foot of the page.
|E-mail this story to a friend|
Links to more Americas stories
To BBC Sport>> | To BBC Weather>> | To BBC World Service>>
© MMIII | News Sources | Privacy