Boomer From United States of America, joined May 1999, 102 posts, RR: 0 Reply 1, posted (12 years 2 months 4 weeks 7 hours ago) and read 1460 times:
I know of no mandatory retirement age, flight hours, or cycles for any common aircraft. The decision to retire a particular aircraft is purely economic...how much is it costing to keep airworthy? There are several DC10 and B747 aircraft that have accumulated well over 100,000 flight hours. Several DC8 and some B737 aircraft are pushing their way to this threshold also. It is conceivable that some of the Ex-American and Ex-United DC10's being converted to freighters by FedEx will end up seeing over 200,000 flight hours before they hit the scrapyard.
Tom2katie From , joined Dec 1969, posts, RR: Reply 2, posted (12 years 2 months 4 weeks 3 hours ago) and read 1460 times:
Many aircraft do have time and cycle limits, some of which do mandate retirement of components which may make it economically impossible to continue the aircraft in service. The Twin Otter has life limited wings. At 35,000 hours (or less for the 100/200 series), the wing boxes and mainframes must be replaced. Many operators choose to do this as there is no life limit on any other airframe component and the aircraft is not replaceable. At 40,000 cycles, 100 series Dash 8s must be sent back to the factory for extensive structural and fuselage bonding work, which is extremely expensive. Many operators choose to sell these aircraft prior to reaching this time limit. I would agree, however, that I have never heard of an airframe itself that is life limited. Most can be continued in service with a certain amount of inspection and repair.
JETPILOT From United States of America, joined May 1999, 3130 posts, RR: 32 Reply 3, posted (12 years 2 months 4 weeks 2 hours ago) and read 1450 times:
Every single plane ever made has a design life limit.
Some of the design life limits are as follows:
747 20,000 cycles, 60,000 hours, or 20 years
767 no cylce limit, 100,000 hours, or 40 years
A300/310 36,000 cycles, 60,000 hours, or 20 years
L1011 115,000 cycles, 210,000 hours, or 20 years
DC10/10/30/40 42,000/30,000 cycles, 60,000 hours, or 20 years
The life limit of an airframe means that the airframe has been tested to these limits in simulation. Known issues found during testing have been dealt with and airworthiness directives issued. From what I understand the manufacturer must implement a maintenance program approved by the FAA to extend the life of the plane past the proven life limit.
The fleet leading planes in hours as of 07/99 are as follows: