Citation Hemisphere Program Dead It seemed that there was a glimmer of hope for the Cessna Citation Hemisphere program. However, the increased issues pertaining to the Safran Silvercrest engines that were meant to power the new large cabin jet just would not allow the program to move forward. Problems primarily with the high-pressure compressor (HPC) could not be sorted out. Safran suggests that recent tests were more-than-satisfactory but more trials were needed to confirm the performance parameters were being met. Safran said, "[they need to] confirm engine improvements and complete overall engine performance and durability validation".