Air Force C-135

Derived from Boeing's prototype 707 jet airliner in the early 1950s, the C-135 has been a visible successful partner of the Air Force since the first one was acquired in August 1956. Although they have performed numerous transport and special-duty functions, most of the 820 units have been KC-135A Stratotankers for the air refueling mission. In this photo, the movable "flying boom" is visible under the tail.
See: http://www.military.cz/usa/air/in_service/aircraft/kc135/kc135_en.htm
...
...
Flying in a KC-135 does give us an opportunity to see some interesting sights.
...
...
This is a medivac (trainer) on a KC-135.
This aircraft is an air tanker.  We also use it as needed.
...
...
PROFILE
Click on thumb photos
for larger view
 BOOM CONTROL
...
B2 CLOSE UP		 ...
B2 REFUELING		 ...
TAIL VIEW

None of the air strikes on Afghanistan would be happening without in-flight refuelling. 
US Navy jets have a limited range. The "combat radius" of even the latest version of the F/A-18, for instance, is only about 450 miles (720 km) with four 1,000 lb (453 kg) bombs, the standard two Sidewinder missiles for self-defence, navigation and targeting equipment and two 480 gallon (400 imperial, 1,818 litre) external tanks. 

The nearest targets in Afghanistan might be at least 1,000 miles (1,600 km) away from the US Navy aircraft carriers. The F-14 and F/A-18 planes are in the air for seven or eight hours and need refuelling at least four times during every sortie. 

Land-based fighter-bombers have similar limitations. 

Even for the long-range bombers, refuelling is essential. A big B-52 has a nominal range of well over 8,000 miles (12,870 km) - but once it is carrying a bomb load this reduces dramatically. 

So bombers flying from the United States to attack Afghanistan also have to refuel several times on the way out and back. 

There are two main types of in-flight refuelling system in current use: 

Drogue - a hose is winched out from the tanker with a cone-shaped basket on the end. The receiving aircraft has a boom or probe which its pilot flies into the basket. Used by most air forces and by the US Navy. 
Boom - a fixed boom is lowered from the tanker then the end of it is extended into a socket on the top of the receiving aircraft. Used by the United States Air Force. 
The advantage of the boom method is that the fuel line is bigger so more fuel gets transferred quickly. 
During Operation Allied Force in Kosovo, Nato had problems providing sufficient in-flight refuelling capacity because of a lack of suitable bases near to the combat area. Afghanistan presents similar problems. 

The big tanker aircraft are typically converted airliners. Those on aircraft carriers are much smaller and have a limited capacity. 

The US Air Force operates KC-10 Extenders and KC-135 Stratotankers. The RAF has Tristar and VC10 tankers - two industry groups are bidding for a contract to provide a replacement by the end of the decade.

SOURCE
Go to: Planes Index