Originally Posted by
forgot to bid
You know I think we covered this already but just in case we didn't:
May 22 (Reuters) - Delta Air Lines:
U.S. carrier Delta Air Lines will continue to sit out a wave of orders for the latest fuel-saving narrowbody models produced by Airbus and Boeing as it waits for newly developed engines to prove themselves in service, Chief Executive Richard Anderson said on Wednesday.
The two manufacturers have stacked up orders for more than 3,000 of the revamped models, the Boeing 737 MAX and the Airbus A320neo, which boast fuel savings of around 15 percent from the second half of the decade.
"We'd rather get toward the end of a production line because one, the airplane has probably been stretched, and stretched economics are always better than the original economics," Anderson told Reuters reporters and editors at Reuters New York headquarters.

Anderson has stated this for years, and it is a proven smart strategy. Look at the troubles the 787 has caused UA by biting the bullet and taking the 787 early. Years delayed, and then a 2+ month grounding after it finally entered service. Not to mention the major capex costs of a plane like that.
I don't blame him one bit. We have gotten 3 MD-90s for the price of 1 new 738. (reason 48 why the narrowbodies should pay the same, but I digest)
FWIW, the new 321s have much higher thrust motors than the 739 and a much higher takeoff weight.