Answer: Short run decision
Explanation: In economics, the time period of a business organization in which one factor of production is fixed while the others are variable is called short run decisions.
In short run period, if the firm wants to increase its output potentially it can do so by increasing the variable factors amount.
As in the given case, Boeing is increasing its jetliners by increasing the time period, that is a variable factor.
Hence we can conclude that it is a short run decision.