Physical characteristics have only a partial influence on operating costs. You are correct on the jetBlue EMBs, but with most other airlines, the a 90 seat CRJ derivative will cost less than an equivalent 90 seat mainline plane such as an A318. Why? the CRJ900 will almost always be flown by the 'feeder' airline. In the US, the majors, outside of AMR, the feeder's are operated as separate companies. The feeder pilot wages are low and the majors usually pay on a fee per departure, influenced by aircraft type. There's an obvious incentive for the majors to even subsidize the acquisitions of more RJs by the feeder airlines. Sure enough, this is exactly what has happened. In Canada, with AC's Jazz a wholly owned subsidiary, AC wanted to drive as much business to be flown by their Jazz subsidiary as possible. Why? The cost to operate is less, mostly from the lower pilot wages. This exact issue was one of the key sticking points a few weeks back when it looked like the Judge was going to order the trustees to liquidate the airline. If it was straight operating costs, wages being equal, things would be more obvious, but alas they are not. Matthew On Sunday, June 22, 2003, at 08:58 PM, Alireza Alivandivafa wrote: > In a message dated 6/22/2003 12:22:59 PM Pacific Daylight Time, > mmontano@xxxxxxxxx writes: > > << Just like United, US Airways, Delta and even Jet Blue and Air Tran. > >> > > Remember that jetBlue is flying 100 seat EMBs, that are not even > called ERJs > anymore. They are so close in capacity to the 717 and A318, it is a > legit non > RJ. Also, it has bigger range than the 717. >