Test methods to record the forces required to jettison a Sikorsky S92 in-cabin push-out window

- First known report of push-out window jettison forces.
- High inter/intra helicopter variability in jettison forces.
- Good level of agreement between FEA model and actual helicopter window.
- Training should use similar forces to those collected from the actual helicopter.

This paper describes the development of a purpose built force plate designed to record the forces necessary to jettison a Sikorsky S92 helicopter in-cabin push-out window. Although the in-cabin push-out window is not considered an emergency exit under any international regulation, it is in most cases the closest exit located to passengers and would likely be used as the primary egress point in the event of a capsizing following a ditching. The force plate was held in place with two vacuum actuated suction cups and recorded manual forces applied to the helicopter window by the authors. A total of 17 trials were carried out on eight different windows in three different S92 airframes. The results suggest that there is significant inter/intra-aircraft variability in the amount of force required to jettison the push-out window. This variability was attributed to the seal system used to hold the window in place and was validated with an FEA model. Significant differences in required jettison forces were also associated with the type impact (static push versus a dynamic strike) placed on the window. Based on these findings, further testing of the in-cabin windows should be carried out at other offshore heliports to identify a standard range of acceptable jettison forces within the existing fleet of S92s. Finally, these forces should be incorporated into all future helicopter underwater egress training that is used to prepare passengers for egress from an S92.