Saudi Arabia plans to buy 20 C-130J military transport planes, five KC-130J refueling aircraft and related equipment from Lockheed Martin Corp. (LMT) valued at about $6.7 billion, the Pentagon said today in a statement.The Pentagon’s Defense Security Cooperation Agency notified Congress of the potential sale to Saudi Arabia, the agency said in a statement posted on its website. It said Saudi Arabia needs the airplanes to “sustain its aging fleet, which faces increasing obsolescence,”The C-130J-30 variant of the four-engine turbo-prop plane that Saudi Arabia is seeking has 15 extra feet of fuselage compared with the plane’s standard model, according to Lockheed, the plane’s maker. The extra space lets the plane carry two additional cargo pallets, according to Lockheed’s website. The KC-130 J refueling plane is also made by Bethesda, Maryland- based Lockheed.