Boeing is warning that further delays could occur in its 747-8F certification campaign as it adds a fourth aircraft to flight testing.

Jim Albaugh, president and CEO of Boeing Commercial Airplanes, maintains that first delivery to Cargolux will take place by year-end, but quickly adds: "There's risk to that."

"Every day we're trying to build contingency, every day we're trying to make sure that we have this airplane in a position where we can deliver it at the end of the year," he explains.

Albaugh says that the 747-8F is at a greater risk of missing its delivery target than the 787. To reduce this risk, Boeing will add a fourth flight test aircraft, likely the second production aircraft (RC503), for use in engineering flight tests.

Three 747-8F test aircraft are flying today, and have accumulated around 300h over 140 flights, says Albaugh. The first test aircraft, RC501, is based in Moses Lake, Washington for flutter testing, another two, RC521 and RC522, are based in Palmdale, California, and transitioned from Washington State on 9 May and 19 April, respectively.

Boeing's 747-8F flight test programme requires 1,600 flight hours and 2,100 ground hours.

Additionally, the company expects the US FAA to grant Type Inspection Authorisation in "the next few days", says Albaugh, kicking off certification operations.

The 747-8F has absorbed a year's worth of delays following extensive design changes and resource starvation that stifled its supply chain. Those delays pushed the 747-8F's entry into service from the fourth quarter 2009 to late 2010.

Source: Air Transport Intelligence news