100k flight hours is like 30-35 years for a NB and you are looking for 160k?
I assume your buddies at Pratt come up with something that doesn’t fit before that time. If any oil is left over anyhow..
JetBlue averages 11.77 hours per day, I believe there is room to increase. That is 4300 hours/year. So a little less at 28 years for 120k.
LH is scrapping a 26 year old A320 soon as there aren't enough hours left to justify a heavy C check. I'm not aware of an aircraft taken to the limit as they must be maintained earlier at every step, so the last bit of life. Did you see the part on maintenance? Extending allowed hours cuts shop visits and thus costs.
I'm not sure what you mean by find something that fits... Airbus likes support revenue. If they didn't, the A320 would be stuck at 48k FC and 60k FH. They'll like it for their A220 too.
Oil? We'll find fuel. E.g., biofuels. It is amazing what Happens when the price goes up. Suppliers find more. When fuel is cheap, why bother?
CFRP allows cheap life extensions. The 787 certified for 200,000 FH is insane. I'm not aware of a widebody going past 150,000 FH. But customers like servicing on longer intervals...At 15.5 hours/day that is 35 years. There is no business case to pay extra for that durability. But greater aircraft availability due to longer C check intervals? That sells.
A c-check take n days if every 10,000 FH (IIRC current A220) or every 17,777 (160k). Corrosion limits are every 4 years. So for JetBlue, 160,000 FH means they would go to the shop due to corrosion days before hours. Higher cycle airlines would always maintain on cycles, even if certified on 120k. Meh...
I love the A220, NEO, and MAX corrosion margins. So much better than the old coatings (it is why all aircraft are mostly green today prior to painting).
I think Jetblue has the highest utilization of any NB fleet, 11.7 hours a day is not typical. Probably because of their transcon and East coast operations. 4-6 cycles a day, 10 hours seems typical of a NB lifetime, globally. After 20-25 years better engine technology boils up, system MRO goes up, environmental restrictions come in, shortening the economical life time of an aircraft.
I think apart from thermodynamic improvements, propulsive efficiency requirements will keep driving higher bypass ratios. It seems at some point the aircraft configuration needs to adjust to that, maybe 100.000 hrs / 30 years after initial operations.. of course all estimations, averages. I like the CSeries too, specially with the big, quiet GTF's. But 160.000 hrs seems very long, specially for NB. Has any NB ever flown that much?
No narrowbody has flown that much. None will.
No MD-80 ever flew 110,000 cycles. Heck, the top was scrapped just below 100k. None has flown the allowed 150,000 FH. But every operator appreciated the long maintenance schedules.
C checks can be at 1/9th or 1/16th of the total life. Most are going to the later (shorter checks). Every 3 (for 1/9th) or 4 c checks (for 1/16th) must complete the heavy maintenance cycle.
LH has worn out A320s on hours. The plane hasn't flown 120,000 FH. One doesn't perform a final heavy c-check unless at least 10,000+ FC and 20,000+ FH are usable after the check.
A cycle is good for one interval. For the A220, I believe it is on a similar patter (E-jets on 1/16th).
Do currently, a c-check must be at the earliest of:
I proposed a maintenance schedule that would be at the earliest:
Since maintenance is roughly
25% line maintenance on airframe
25% line maintenance on engines
25% c-check (heavily biased toward heavy C checks)
25% engine overhauls.
What I propose saves about 14% in maintenance costs.
So this isn't for aircraft life, it is to perform the testing to extend maintenance intervals.
The #1 advantage of the huge PIP on the A320 going from 60,000 FH to 120,000 FH was going from a c-check every 6,666 FH to an extended 13,333 FH. Now reinforcements were required in the wing send tail section, but work to that took about 2 days in parallel with other c-check work and payed off by the next c-check.
I believe the A220 has the structure. Most of the FH cracking is the wing and tail. Cycles are found by cracks in the body, wing root, wing box, nacelles, pylons, flap Joints, and gear bays. CFRP is practically immune after 60,000 FH. So as long as the tail is built right, why not go for cycles? It cuts maintenance bills. If 1,000+ aircraft are sold, the enhanced maintenance plans are sold for enough to pay for testing.
Airbus is working to extend the A320 limit of validity. It isn't that an airline worries about wearing out an A320 24 years from now, it is the reduced maintenance.
The 737 has a limit of validity of 110,000 FC and 125,000 FH. For airlines that fly sub 2 hour missions, that means reduced maintenance costs in high cycle duty due to longer intervals for maintenance.
Wouldn't we want the A220 to have even longer intervals?
The extremes seen so far are widebodies. Airbus typically certifies for 36,000 FC and 160,000 FH. So long in hours and cycles that A340 and A380 are being scrapped at the first interval when maintenance inspections can no longer be differed or 12 years.
I see A220 being scrapped at the end of the 2nd interval (about 24 years) with significant differed work on the plan I proposed. So in effect, I am proposing 160,000 FH to certify to allow for a lower cost 2/3rds life of less than 106,666 FH.
A great example is the 787.
7,333 cycles (Only Japan domestic, that I know of)
22,222 FH. Umm... Not happening.
The 787 sells well as maintenance is usually on the clock (corrosion limits). That makes it easy to plan.
Hopefully I have made it clear for economics for two heavy maintenance cycles, not for a 30+ year life I want to see the A220 FH certification brought up to 160,000 FH. Predictable maintenance intervals is easy to plan.
The current intervals are too short (every 10,000 FH).
You know nothing John Snow.