Sonic67 From United States of America, joined Jan 2005, 292 posts, RR: 0 Posted (9 years 4 months 3 weeks 1 day 5 hours ago) and read 3157 times:
I was wondering if any commercial or privately owned 707 carriers other than the military have re engine their AC with modern high bypass turbofan such as the Pratt & Whitney CFM56 or the TF33 (JT3D) conversion kits. The newer engines can increase thrust by 35 percent and fuel consumption by 15-22 percent. I was wondering can the newer engines make it economical to operate the 707?
707fan From Norway, joined Jun 2001, 36 posts, RR: 2
Reply 1, posted (9 years 4 months 3 weeks 1 day 4 hours ago) and read 3118 times:
In 1978 Boeing contemplated offering a 707 version to be powered by CFM56-1B turbofan giving 22000ib trust. This move followed studies carried out for the USAF concerning the re-engining of the KC-135s and although generally similar to the 320B, the 700 as intended for long range work. One civil airframe was equipped with the new engines and was first flown 27 November 1979. Trials were completed during the following July but lack of airline interest or modernised 320B/Cs sealed the fate of the project.
Although there was an increase in weight, this penalty was more than offset by lower fuel consumption, reduced noise levels and less smoke emission. The only civil airframe was reverted to normal and sold to the Government of Morocco as CN-ANR in 1982.
SATL382G From , joined Dec 1969, posts, RR:
Reply 7, posted (9 years 4 months 3 weeks 23 hours ago) and read 2957 times:
Quoting Sonic67 (Thread starter): I was wondering if any commercial or privately owned 707 carriers other than the military have re engine their AC with modern high bypass turbofan such as the Pratt & Whitney CFM56 or the TF33 (JT3D) conversion kits
The CFM56 is a SNECMA engine not Pratt & Whitney. Many 707s & 720s got the JT3D conversions in the 60s, AA did a bunch of these as I recall.