Well, i haven't heard a 747-100, however, all of UPS's 741's are fitted with chapter 3 hush kits, while the VC
-10 ( i believe) isn't, therefore , the VC
-10 would be louder, especialy if the VC
-10 had NO hush-kits , although i doubt that would be alowed any more
Happy Flying !!
P.S-Hello from the other side of the Atlantic
Always stand up for what is right, even if it means standing alone..