FlyABR From United States, joined Sep 2003, 474 posts, RR: 0 Posted (6 years 1 month 2 weeks 6 days 19 hours ago) and read 3286 times:
Was just thinking about how old the NW fleet of dc9s and dc10s are. Many NW diesel 9s are way over 30 years old. Just how long can commercial jets fly before they need to be retired? And are there govt regs against aircraft being to old for commercial service? Thanks for any info you can provide. I'm kinda new to this game...
Matt D From United States, joined Nov 1999, 9502 posts, RR: 55 Reply 3, posted (6 years 1 month 2 weeks 6 days 19 hours ago) and read 3215 times:
I know of no government imposed age limit imposed on aircraft per se. Modern maintennance can theoreticaly keep a plane in the air forever. As noted, it has more to do with hours and/or cycles; there are established airworthiness directives that need to be adhered to. Also, as noted, there are many variables: how many cycles per day, stage length of each cycle, and so on.
Beltwaybandit From United States, joined Mar 2003, 495 posts, RR: 0 Reply 4, posted (6 years 1 month 2 weeks 6 days 19 hours ago) and read 3208 times:
Manufacturers put an absolute limit (e.g. the 100,000 cycle limit), but I believe that can bump that limit upward.
Cycles are a much more valid measure of wear. Flight hours work the engines, but engines are continually renewed with new disks and life-limited parts. Airframes take a beating on landing and takeoff. Corrosion also takes a toll.
Matt D From United States, joined Nov 1999, 9502 posts, RR: 55 Reply 5, posted (6 years 1 month 2 weeks 6 days 19 hours ago) and read 3192 times:
Those Northwest DC-9's, like the USAF B-52's, have been in the air so long, and "rebuilt" so many times that you probably won't find an original rivet or bolt in either of them.
Na From Germany, joined Dec 1999, 6749 posts, RR: 8 Reply 6, posted (6 years 1 month 2 weeks 6 days 19 hours ago) and read 3159 times:
Looking back it appears the 747 is a very longlasting type of aircraft. There are many converted Freighters around that are well past their 30th birthday (a good part of UPS´, Evergreen´s and Kalitta´s fleet). And some pax-747s too were built when the Vietnam war was still reality.
Of cause this has to do with the Jumbo Jet being a longhaul aircraft (the domestic 747s in Japan don´t fly that long) doing less cycles (compression/decompression put huge stress on airframes) than shorthaul aircraft (the NWA DC-9s are a exception here).
In comparison to the 747 most A300s from the 70s have been retired. That most DC-10s and L-1011s have also been retired and many scrapped has also to with them being aircraft of manufacturers no longer existing (and parts in somewhat shorter supply I guess).
While you can expect most of the B747-400s built in the 90s still flying in 2020, and a number of them as converted freighters, for example many of the shorthaul 777-300s serving in Asia will be beercans by then.
BoingGoingGone From , joined Dec 1969, posts, RR: Reply 7, posted (6 years 1 month 2 weeks 6 days 19 hours ago) and read 3125 times:
The 747 lasting that long is a result of better utilization. It spends more time flying than it does on the ground. Short haul aircraft can do up to 10 cycles per day or more, a 747 might do 2 or 3. Thus prolonging it's life.
About the NWA DC-9's. They are on their last leg. My father-in-law has been working on the same birds since they were part of Republic. He says they can't get more than another 5-6 years out of them, if they are lucky.
FlyABR From United States, joined Sep 2003, 474 posts, RR: 0 Reply 8, posted (6 years 1 month 2 weeks 6 days 18 hours ago) and read 3069 times:
hummmm...if find that hard to believe. NW would have to replace some 150 aircraft then in 6 years time. guess they better get that 717 order in pronto!!
Ckfred From United States, joined Apr 2001, 3037 posts, RR: 2 Reply 9, posted (6 years 1 month 2 weeks 6 days 18 hours ago) and read 3030 times:
Part of the lifespan depends how the changes in technology. Planes that needed a flight engineer tended to disappear as labor costs increased. After September 11th, most airlines put their 727s on an expedited retirement schedule. American had planned to fly 727s until the end 2004, but they would up being retired by 4/30/02.
A lot of 727s, 737-200s and DC-9s were retired in the late 1990s, because Federal noise regulations required either new engines or hush kits.
Sometimes, an airline may find that a plane simply does not fit well into the fleet. American has not been completely happy with the Fokker 100s. They aren't suited for very short hops, and mechanics find they are more difficult to work on then Boeing, McDonnell Douglas, and Airbus aircraft. That's why American never exercised its options and has started retiring the Fokkers this year, even though the first Fokkers were delivered in 1991. Add to the fact that parts are difficult to get, because Fokker went out of business.
Elwood64151 From United States, joined Feb 2002, 2477 posts, RR: 9 Reply 10, posted (6 years 1 month 2 weeks 6 days 18 hours ago) and read 3027 times:
Na:
You're forgetting that quite a number of DC-10s are also still in cargo and passenger service.
The DC-3 has been around for nearly 70 years. Douglas designed it to last forever. With proper maintenance and an O2 tank, they'll be flying them on Mars.
The fact is, there is no real limit to how long an airframe will last if it is properly maintained.
Those who fail to learn history are doomed to repeat it in summer school.
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