Editing Turbofan (section)

===Basic two-spool===
[[File: Dual-spool axial-flow compressor.png|thumb|A dual-spool [[Axial compressor|axial-flow compressor]].]]

Many turbofans have at least basic two-spool configuration where the fan is on a separate low pressure (LP) spool, running concentrically with the compressor or high pressure (HP) spool; the LP spool runs at a lower [[angular velocity]], while the HP spool turns faster and its compressor further compresses part of the air for combustion.{{Citation needed|date=September 2018}} The [[Rolls-Royce BR700|BR710]] is typical of this configuration. At the smaller thrust sizes, instead of all-axial blading, the HP compressor configuration may be axial-centrifugal (e.g., [[CFE CFE738]]), double-centrifugal or even [[Mixed flow compressor|diagonal/centrifugal]] (e.g. [[Pratt & Whitney Canada PW600]]).