Those famous words "changes in the basic design of " have been much discussed 
On the basis of those words, most mods which most people working in the business say are Major are in fact Minor.
The IA tells me that he wants an STC or Dual Release Certificate to wire it into the aircraft permanently.
If he says “an STC or Dual Release Certificate” then he is clue-less.
It’s a bit like saying “I need petrol in the car, or ice cream for my kid to stop him hassling me”.
But, to be fair, I have heard the opinion before, where the existence of an EASA-1 or 8130-3, is seen as permitting a particular installation. This has appeared on the Socata owners’ group multiple times (where nobody dares to question anything from a particular individual; you get kicked out if you do that) and is simply wrong.
What interconnection (what data flow and from what to what) are you looking for, Colin?
AnthonyQ wrote:
It could be (frequently is) that connecting something to the aircraft wiring and especially to an avionics connector, has a potential “on, changes in the basic design of radio communication and navigation equipment approved under type certification or a Technical Standard Order that have an effect on frequency stability, noise level, sensitivity, selectivity, distortion, spurious radiation, AVC characteristics…etc.” which qualifies such an installation as a Major Alteration.
If the installation only desires to connect the ADL to the RS232 out of the navigator, then claiming that this could have an effect on the characteristics of the TSO’d equipment would be extremely anal.
tomjnx wrote:
If the installation only desires to connect the ADL to the RS232 out of the navigator, then claiming that this could have an effect on the characteristics of the TSO’d equipment would be extremely anal.
I would agree…however I have even heard the opinion that only a cigarette lighter may be used in a cigarette lighter socket! Anyway, how is this issue handled in an EASA registered aircraft?
In the Cirrus, at least, it is called the “12 V Convenience Outlet”, and not “Cigarette Lighter Socket”. The POH mentions no restrictions.
We need a thread on examples of anal certification behaviour 
Flyer59 wrote:
In the Cirrus, at least, it is called the “12 V Convenience Outlet”, and not “Cigarette Lighter Socket”. The POH mentions no restrictions.
But actually that is a good example. Since you can plug anything in to the “convenience outlet”, thereby connecting all manner of uncertified and dirty equipment directly to the aircraft electrical system, presumably with no in-line filtering, there should be no objection to properly providing a dedicated power supply to a device by wiring it into a circuit breaker…that would clearly not be a major alteration (for an N-reg)…. Is there a similar argument for connecting a device to a data bus?
Peter wrote:
We need a thread on examples of anal certification behaviour
Or anal thread behavior… (guilty, as charged…)
The data flow (as I understand it) is from the GPS/NAV/COM to the ADL110B.
The ADL110B unit is not providing data to the GPS/NAV/COM (I am no expert on this).
I think that is correct. It is only the active flightplan that is transferred to the ADL Also the ADL has its own GPS receiver and does not need any other data.
