| The 'hot' helium from the air precooler is recycled by cooling it in a heat exchanger with the liquid hydrogen fuel. |
| In addition, unlike the LACE concept, SABRE's precooler does not liquefy the air, letting it run more efficiently. |
| Previous versions of precoolers such as HOTOL put the hydrogen fuel directly through the precooler. |
| The RB545's precooler had issues with embrittlement, excess liquid hydrogen consumption, patents and the Official Secrets Act, so Bond developed SABRE instead. |
| Part of the air then passes through a precooler into the central core, with the remainder passing directly through a ring of bypass ramjets. |
| In April 2012, REL announced that the first phase of the precooler test programme had been successfully completed. |
