Thanks for that input, SiClick. If the services were to retain AI then I would expect their Accident Inspectors to be professional ones to the same degree and expertise as those in the AAIB. Otherwise you have the same process as bedevils MOD Airworthiness where people are posted in for a tour and just about getting into their stride when they move on. In (old) RAF terms AI would be a branch, like GD/P, ATC etc where you would spend the bulk, if not all, of an entire career. If that's a no no, then the Tri-Service AI unit would be also and the solution would have to be like the MAA, ie a separate independent and professional MAAIB. Those inspectors would then presumably be civilian though ideally ex-service. That will rankle but anything less than fully professional and objective Air Accident Investigations are pointless and dangerous.