Peter wrote:
They probably won’t come here and post it
Not just for the sake of it, certainly, but if they participate here anyway why not?
I suspect it may mean that the item must be approved for the particular installation, either specifically (e.g. STC, AML) or generally (TSO).
That’s a reasonable interpretation. Not a problem in our case.
I can even answer you in Swedish… local copy
If you prefer English, the answers are in the EASA Certification Memorandum local copy
21.A.307(c) is indeed a very useful provision. It is not as restricted as hypothesised above.
In 2014 we had to have the landing gear motor on our Twin Comanche overhauled. We sent it to an EASA POA in the UK where the work was done and it was duly returned with a Form 1. Later in the year the motor failed while the gear was in transit. My co-owner used the manual extension procedure, and we had the gear motor removed and sent off to The Guy who everyone acknowledges as the expert on Comanche gear motors. He found the problem on a cursory examination: at the overhaul, one of the wires had been routed in a way that would cause it to burn out within a couple of minutes of cumulative time in operation (a good guess, given that it operates for a few seconds every flight). He repaired it and returned it, but being a bloke in a shed in the US, he couldn’t provide an 8130-3 let alone an EASA Form 1.
So we decided to install it under 21.A.307(c). The only hitch was that the our maintenance organisation refused to believe that this was permitted. After the personal intervention of the head of GA certification at EASA and the head of the UK CAA GAU, the head of airworthiness policy of the UK CAA wrote a letter to the maintenance organisation confirming that the part could be reinstalled under 21.A.307(c). Needless to say, that was our last transaction with the maintenance organisation in question. I’m delighted to see that your club’s avionics shop has a more enlightened view of the regulation.
bookworm wrote:
I can even answer you in Swedish… local copyIf you prefer English, the answers are in the EASA Certification Memorandum local copy
The Swedish presentation emphasised that it (the presentation) concerned new parts, but is there such a limitation? In my case with used avionics the avionics shop said 21.A.307(c) could be used.
Yes I think the question of whether this is for new parts only is a key aspect.
Is this concession usable for a flying school or is it restricted to privately operated planes?
bookworm wrote:
The only hitch was that the our maintenance organisation refused to believe that this was permitted
More probable that they refused to admit it was permitted.
Peter wrote:
I think the question of whether this is for new parts only is a key aspect
The example provided by Bookworm was for a used part (the motor) and this was backed by the authorities, so it seems it does not only apply to new parts.
Peter wrote:
Yes I think the question of whether this is for new parts only is a key aspect.I can’t see any reference to that in 21.A.307(c). Indeed it says that the component has to be in “condition for safe operation” which more or less implies that it can be a used part. The Swedish presentation was about new parts but that doesn’t mean that 21.A.307(c) doesn’t apply to used parts. It is clear that my avionics shop believes it does.
Peter wrote:
Is this concession usable for a flying school or is it restricted to privately operated planes?
You should rather ask if it usable both for commercial and non-commercial operations. A school can be a non-commercial operation. (Well, not in the UK maybe.)
ML.A.501 makes no distinction between commercial and non-commercial ops and part-ML as a whole is applicable to both kinds of operations — although not to CAT, but a commercial flight school is not CAT.
Come to think of it, the Swedish presentation predated part-ML by several years and it also stated that it was applicable to CAT, so maybe that’s the reason for the restriction to new parts.
There are all kinds of angles on this thing. This old one definitely exists but very few Subpart F companies have the privilege to do it.
Clearly there is a lot of resistance in the industry and the national CAAs, and if your maintenance company refuses to go along, you have no option.
Peter wrote:
Clearly there is a lot of resistance in the […] national CAAs
This:
bookworm wrote:
After the personal intervention of the head of GA certification at EASA and the head of the UK CAA GAU, the head of airworthiness policy of the UK CAA wrote a letter to the maintenance organisation confirming that the part could be reinstalled under 21.A.307(c)
seems to indicate there is support from the authorities.
