Chinook 240, the only FADEC I am interested in is the one fitted to ZD576 at the time of the accident. What the RAF/MoD have done since then is, with respect, a matter for them (although you might wish to search for the Chinook Mk3 threads).
At the time of the accident, EDS Scicon, were requested to analyse the FADEC code fitted to the Mk2. Their findings are below.
After reading 17.4% of the primary lane of FADEC software and 19% of the FADEC's reversionary, or back up, lane, they identified the following faults:
- 56 anomalies graded Category 1
- 193 anomalies graded Category 2
- 132 anomalies graded Category 3
- 104 anomalies graded Category 4
EDS went on to say, "
In a rigorously developed safety critical system which has been written according to a strict coding standard, the code can be expected to contain none, or very few category one anomalies and only a small number (in the order of tens) category two anomalies. The other types of anomalies are likely to be more common, although in a carefully developed system there ought not to be too many category three anomalies.
A category one anomaly indicates an actual coding error or non-compliance with the documentation. However this does not mean that it necessarily has any safety implications, it may not even affect the overall operation of the system. Each category one anomaly has to be investigated in this case ultimately by Hawker Siddeley to determine its impact on the system behaviour.
When a response from Hawker Siddeley indicates that an error does not have
any safety impact or does not significantly affect the operation of the system,it should be emphasised that latent errors in the code may still have serious implications for future maintenance of the system.”
So, chinook 240, what, if anything, has happened to the FADEC software?
Kind regards,
Brian
"Justice has no expiry date" - John Cook