The AAIB report identifies the issue of the cartridges life as an airworthiness matter and it is however the timex status of the seat had no bearing on the accident. The state of supply of cartridges is a problem for this case, not that they don't exist, they are not available for purchase in general, and that constraint conflicts with the CAP requirement as stated. CAR 632 in the AAIB report is stated to indicate that swept wing aircraft must have their ejection seat serviceable:
"CAP 632 requires the pilot escape systems of swept-wing jet aircraft, such as the Hawker Hunter, to be ‘fully serviceable’. The use of time- expired ejection seat cartridges meant that the ejection seats fitted to G-BXFI did not meet this requirement." [section 3, p201 or the AAIB report] That is not what is stated in the CAP 632, at least at rev 8.
yet:
"If an aircraft is fitted with ejection seats that are an integral part of the aircrew escape system, these should be fully serviceable for all flights. New operators must seek approval from the CAA GAU at the earliest opportunity if it is intended to operate with inert ejection seats or other escape systems, prior to inclusion in their OCM". CAP 632 rev 8, §5.7, p25,
Whether this is post the event is unknown. There are PTF aircraft that it would be unwise to operate without a live seat, there are others that are tolerable risks to the occupants depending on the environment. Having operated both inert and live, there are merits to both cases, however, what they don't do is make the aircraft unsafe to operate, and the opportunity to inert the seats existed within the rules. I would be more concerned with the conduct of aerobatic operations without an operable G-meter, that is not a good look at all, particularly in the light of a botched vertical manoeuvre. The other noted non compliances are of a lesser form than the dropping of a plug from a Boeing, cowls opening up on engines in flight, and the rest of the saga of aircraft production we have grown accustomed to. In the report, there is enough to dwell on related to the processes of maintenance but nothing that was germaine to the failure to achieve entry speed, gate height, or energy over the top. A surprise admission was that the pilot was not trained in the escape manoeuver for missing the gate conditions.
The event was a horrific tragedy, however, IMHO, airworthiness and the PTF did not directly result in the accident.
In respect to Appendix L, what is stated is an issuance of a NPTF, duly signed on 6 July 2006, for the CAA. If there is some confusion on the background, that is a matter for internal review within the CAA or delegate system to correct, however there is a required signature on the document, and that would suggest that the aircraft was legally issued a PTF. The defect in the PTF does not itself invalidate the PTF. Consider the Max8 debacle, the plane was compliant with the TC as approved by the state of manufacture. The latent defect that existed was not known, and at the time of departure the aircraft was operated IAW the TC and associated requirements. After discovery, the issue of the AOM did not alter the airworthiness of the aircraft, that arose belatedly with the issue of an EAD.
The PTF, pyros didn't cause the accident. Running out of altitude did.
Last edited by fdr; 19th Jan 2024 at 10:22.