Why? They and KE were two airlines asking for it.
Perhaps DL is going to connect Alaska and southern foreign destinations? Perhaps Caribean to further.
Why? It's very simple.
First I am not sure the MTOW increase if retrofit table to the current fleet.
Even if it is the case there will be induced cost for recertification of individual aircraft that also include the documentation. It it not just "paper certification" there's a lot to do and it costs a lot of man-hours.
Would an airline spend money on something they do not need?
Now, let's assume they want to do the very hypothetical routes you mentioned. Do they need to retrofit all aircraft in the fleet to achieve the high MTOW? That's costs.
Do they want to have a subfleet with hight MTOW? That's two sets of everything.
I still think it doesn't make sense for Delta to have the A220 with the high MTOW, especially when they have other narrowbody to address other exotic things you mentioned.
Please remember that yields usually drops with stage length. You would prefer have bigger aircraft for long routes.
The MTOW increase was analysis/license. To my knowledge, there is no physical change to the aircraft, just buying the right paper and updating the maintenance plan.
Delta requested the update. So obviously it makes sense to them.
As an AirFrance thread, it makes sense to me for them to buy it.
Other than fractionally higher ATC fees and the licence/maintenance costs, why wouldn't DL buy the flexibility? Why wouldn't AF?
Every MTOW increase I ever worked sold far better than expectations. This one seems to, as we Americans say, hit the ball out of the park. Clean out of the park...
CFRP is wonderful. It is always built first with too much margin, then MTOW is increased.
AirFrance would be able to use the highest MTOW for great flexibility to/from Africa.
Just as AirFrance would benefit from a higher MTOW 787-10, possibly their next order.
When someone has already paid for something, it is best to ask why they did instead of claiming it makes no sense. The MTOW increase for the A220 is in such demand a future increase, with structural changes, only makes sense.
Before my very first aerospace engineering meeting with a customer, my manager warned us "smile when they throw money our way and tell them the advantages of buying the PiP. Never tell them they don't need it as we always find other customers willing to buy that PiP." In that meeting we convinced the customer to give us $500,000 more profit per engine. Later the customer showed me how it increased their profit $500,000/year per aircraft with the PiP.
Delta knows how to make money. If they want a MTOW increase, they get it. I have no idea if they paid a fee or if it was agreed to as part of a top off order.
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