AboutDottie Norkus Expertise I can address questions concerning: airline pilot employment & entry level airline careers in the Unites States, women pilots, flight training, pilot certification, flight scholarships (mostly for women), aviation & airline safety topics, aviation accident investigation, air carrier accidents and airline operations.
***Please note, I cannot address flight training or career queries from outside the United States. If you are not in the USA, please direct your question to the message boards at www.PPRUNE.org as you can surely find an answer there. For those in India try http://www.indianpilots.com
Also, I cannot address questions about aero engineering degree programs/careers or aviation management careers.
Experience U.S. Regional Airline Pilot. I have also had 15 years previous experience in airline ground operations, as well as a part 91 commercial skydive pilot and ferry pilot.
Organizations I belong to I am a charter member of Women In Aviation International as well as the International Organization of Women Pilots: the Ninety Nines. I keep a database of flight scholarships for women (mostly SW USA) and mentor student pilots.
Education/Credentials Embry Riddle Aeronautical University certificate in Aviation Safety/Accident investigation.
Question Can you tell me the avereage life span of a commercial aircraft for instance a 747 and what would determine it being taken out of service, and if it taken out of service what would happen to it.
Answer The "lifespan" of an airliner is not measured in time, but pressurization cycles. Each time the aircraft is pressurized during flight it's fuselage is subjected to stress. The "lifespan" of the aircraft is reached the metal fatigue’s and cracks.
A "service life of 20 years" is as generalization that figures 51,000 flight hours and 75,000 pressurization cycles for most aircraft. If an aircraft is used on long haul routes it experiences relatively few pressurization cycles in it's "life" it will last far beyond 20 years.
As an example only a few years ago, the average age of a jet in the operating fleet of Northwest Airlines was 20 years according to a 1999 article. A 2005 news clip noted NWA continues to operate DC-9-31 aircraft that have an average age of 34 years old! Boeing 747s are also flying well beyond 20 years. The oldest active 747, N771PA, was originally delivered to Pan Am in 1970 and at 36 years is now in service with United Parcel Service/UPS.
However, while the airframe still has 'life' in it, some aircraft may not be economical (fuel hogs) to operate so their careers will be shorter. If the aircraft is damaged in any way where the costs of repair outweight its value it will also be taken out of service.
Once taken "out of service", as in it will no longer be flown but is worth more as scrap metal than an airframe, it will be broken up and recycled after all it's serviceable parts have been removed. Some aircraft sit for many years in "aircaft boneyards" (storage) before they are scrapped but eventually that is what happens.
Here are some websites dedicated to the more popular boneyards-
If you want to see the process of how old airliners are broken up, get a DVD called "Scrapping Aircraft Giants" available here- http://www.scrappingaircraftgiants.com/
You can read about the life of a Boeing 737 from birth through death at age 28 (with scrapping photos) in this great article from Airliners magazine, volume No. 78, entitled the "End Of The Line - Scrapping an Airliner" by Jay Selman here-
