Boeing 747SP - does the SP stand for slowly perishing?

Courtesy of user Sharpshot on Flightglobal's Airpspace image gallery, here's a great picture of a slightly neglected Boeing 747SP. It began its life as a test aircraft for Boeing as it looked at the possibility of offering a 747SP Combi, before entering service with China Airlines in 1977. It wound up with Kinshasa in 2003 - registration 9Q-CWY - and was then acquired by Capital Asset management in 2007. It now sits waiting for oblivion at Sharjah airport in the United Arab Emirates, where it appears to have been for the past four years...

Credit: user Sharpshot on Flightglobal Airspace