But yes, we "perhaps" don't know exactly what Airbus had in mind in acquiring / investing in the CSeries. And I'm seriously not so sure anymore, particularly since reading some of VV's comments. More to follow soon I hope.
Thanks for your interesting comments on this thread. A lot of them raise some questions that are difficult or impossible to answer. I'll provide my opinion on this one.
I think Airbus's acquisition of A220 is in a lot of ways similar
to Boeing's acquisition of 717.
Neither intended to acquire either product.
Both acquired the product under favorable circumstances.
Both incorporated the product into their product lineups.
IMHO both will run in to the problems mentioned above: the need to protect the cash cows and the relatively small scale of their production lines.
As you mention BBD has already committed to the equipment to upsize the A220 production line.
Yet even if things track well to the plan the end result is they will be producing 1/4th the number of A220s as A320s and would need to double their investment again to get to half the scale of the A320 family production lines.
Maybe a good metric for additional funding is if you want more than 1/4th the A320 production line capacity you should have 1/4th the backlog as the A320 family.
Maybe a reasonable trigger for additional A220 investment would be a backlog of 1500 orders, since A320's backlog is ~6000 frames?
It raises the question of where the next 500 orders come from, never mind the next 1000.
Clearly A220 has a great advantage: it is emergent technology, whereas 717 was mature technology when Boeing acquired the program.
717 came with the advantage of compatibility with all the DC9/MD80 fleets, A220 has no installed base to market into,
Boeing could have chose to stretch 717 just like AirTran begged for, but the numbers did not support growing 717 at the expense of 737.
I think when push comes to shove we'll see A220 have a nice run in its position beneath the A320 and Airbus will not fund a model that overlaps A320.
And yes, this is just my opinion.