Ramon Lopez/WASHINGTON DC

Ten more Boeing B-52H Stratofortress bombers are to be deployed to Europe to help meet NATO's request for 300 additional US aircraft in the Balkans conflict.

Eight hundred US aircraft are involved in the five-week-old Operation Allied Force air campaign. Other nations are also expected to bolster their forces.

Moving the bombers closer to Yugoslavia is part of an airpower build-up requested by US Gen Wesley Clark, Operation Allied Force commander.

On 27 April, US President Bill Clinton authorised Defense Secretary William Cohen to call up as many as 33,000 reservists to active duty - the largest activation of US reserve forces since the 1991 Gulf War.

About 1,000 personnel and 26 aerial tankers in the Air National Guard (ANG)and Air Force Reserve (AFR) will mobilise at first, supplementing 1,500 reservists who volunteered for the NATO air campaign. Over half of the USAF's air refuelling capability, including McDonnell Douglas KC-10 and Boeing KC-135 tankers, is in the ANG and AFR, and the activation of pilots, mechanics and other support personnel is expected to affect the US aerospace industry.

US airlines are preparing for reservist call-ups, but do not expect serious disruptions to services. United Airlines, which has only 850 part-time military flyers among its 10,000 pilots, expects minimal impact because the major US air carrier can turn to pilots serving as instructors and in management positions to fill in for those called upon to support the NATO air campaign. An estimated 10,000 of the 83,000 pilots flying commercial transports in the USA also fly military fixed-wing aircraft and helicopters part-time.

Eight B-52Hs are based at Fairford in the UK and took part in the opening round of attacks on Yugoslavia, firing AGM-86C conventional air-launched cruise missiles.

Twenty-four US Army Boeing AH-64 Apache attack helicopters have arrived in Albania and are being used for training exercises. They will be used to attack Yugoslav armoured vehicles in Kosovo once the order is given by the White House. One Apache has crashed during training.

Senior Department of Defense officials say allied aircraft flew 11,410 missions in the first five weeks, including 4,000 strike and 3,500 combat air patrol missions, despite poor weather. They say the air campaign will intensify as the weather improves.

Gen Charles Guthrie, the UK's Chief of Defence Staff, says more than 200 separate sites have been bombed, including nine of Serbia's 17 airfields, 31 fixed communications sites, both national oil refineries, plus railway lines and bridges. More than 70 of the country's 450 combat aircraft have been destroyed, including 23 of 83 MiG-21s and four MiG-29s.

Kosovo highlights

• Apaches arrive in Albania. One crashes during training, reducing deployed fleet to 23.

• Collateral damage increases as laser-guided bomb loses lock and hits 50 homes, killing 20 civilians, and a Harm anti-radiation missile hits a house in Sofia, Bulgaria, after being launched by the US Air Force against active Serbian air defence radar.

• Attack on Podgorica airfield in Montenegro, home to an air defence radar site and significant numbers of Yugoslav aircraft, mostly light strike Super Galebs, which were also targeted at Sutomor during an attack against the Denotinovici radar site. Port of Bar also targeted.

• Canada, UK and USA sending extra aircraft and many NATO nations deploying more ground troops to neighbouring countries.

• Other targets include more bridges over the Danube, radio and television relay stations.

• Throughout the week NATO has reported no Yugoslav air force activity, little surface-to-air missile activity and few missile launches. No NATO losses reported.

Source: Flight International