Them Fellers at Boeing gots themselves some good engineers and some bad management.

(t-square, stop reading here.)

The fan diameter of the Pratt and Whitney PW1000 engine will be 81".
The fan diameter for the current 737NG with the squished nacelles is 61" inches.

There's no room for a bigger fan.

So Boeing is going to jack up the nose 8"
To do that they have to add a bulge under the fuselage.
They don't want to redo the main gear, so the biggest fan that fits is 70"

That's a 14% difference in fan size with the equivalent fuel burn implications.
Even if the 737 is lighter and more efficient than the A320 it's not more than 5-7% in fuel burn.

The 737RE is a bandaid on a reworked late 60s design.
The A320neo is a re-engined mid 80s design.

If Delta orders the GTF Pratt motors on the Baby Bus order coming up, its a sign of long-term financial planning.

If Delta orders the LEAP-X motor or goes out and orders the 73RE, it's a sign of short-term gain with long-term pain...

Now if Boeing kept the 727 concept they could put 90" fans on the tail

Cheers
George



Cheers
George