Originally Posted by
stratoduck
I just went through the United Airlines 4th-Quarter and Full-Year 2017 Performance.
United Airlines Reports Fourth-Quarter and Full-Year 2017 Performance - Jan 23, 2018
The CASM was not listed for Regional operations, only Mainline and Consolidated. I calculated it from the data provided:
Mainline CASM 12.59
Regional CASM 16.93 (34% higher)
Most of that cost was due to fuel; the regional fleet burns 69% more fuel per available seat mile than mainline. However even excluding fuel, the regional fleet was still 26% more expensive to operate per available seat mile.
Those numbers do not correctly capture the cost differential. If you are able to dig through the SEC (securities Exchange Commission) archives and can locate an Independence Air filing, you'll see that Independence Air's CASM on their RJs was ~25 cents as opposed to their A319 CASM of less than 10 cents.
Those are 50 seat numbers but I doubt that 70/76 seaters could drive the CASM down as much as what's in the United report. Those numbers likely include the EAS subsidy.