Mach2number
I agree. It adds a degree of confidence - a high degree if done properly. The real issue is, as you say, practical implementation. The Safety Case for the seat (in this case) must then be subsumed into the whole aircraft Safety Case for the platform, and what is safe in one application may not be in another. That is why the SI report is so alarming - that the MoD system, post-MAA and Haddon-Cave, permitted the basic Safety Case to be ignored. Put another way, what MoD tends to ignore is the difference between physical and functional safety. It (or rather the manufacturer) will usually check the first, but MoD uses that evidence to sign off both. Martin Baker can say the seat is physically safe, but it cannot say it is functionally safe as it has no control over how it is fitted, maintained or used.