The B-1B Lancer is widely used by the U.S. military to bomb targets over Iraq and Afghanistan.

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Captain Jeff Taliaferro, a 10-year Air Force veteran, flew a B-1B bomber over Iraq as we attacked Saddam's war machine.

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The B-1B has a "variable-geometry" or swing-wing design: The wings are swept forwards, almost at right angles to the body, for take-off and landing and cruising.

BBC: Profile: B-1 bomber

The B-1B - the original B-1A project was cancelled - went into operational use in the mid-1980s but was not used in anger until December 1998, against Iraq.

BBC: Profile: B-1 bomber

For example, when the B-1A program was restarted to produce the B-1B, the per unit cost of the B-1B was three-times higher than the B-1A. Importantly, the B-1B was a modification (albeit a significant one) of the A-model and a gap of just 18 months occurred in the production line.

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The B-1B has some stealth features: A smooth design and the use of radar-absorbing materials gave it an appearance on radar that is said to be only 1% of that of the older B-52 bomber, even though it is only a little shorter - at 146 feet (44.5 metres) - and weighs almost the same.

BBC: Profile: B-1 bomber