Are new engines worth the wait? Not really.

As readers may have noticed from our posts last week, we’ve been analyzing a large set of ADS-B flight data—over 1 million flights—to understand airline operational dynamics better. One key focus has been Total Ground Time (TGT) across narrowbody aircraft types.

The chart below categorizes 737-family aircraft by generation, providing a more precise comparison than the previously posted summary chart. We’ve also included A320 and A321 variants to highlight cross-fleet trends.