EADI/EHSI design mods/certification? Request help.

[Lou DeCrosse]

A request for help:

Is there anyone out there who has any experience/knowledge re fitting a basic EADI and EHSI to a PA23 (Aztec)?

I’m specifically interested in the design mods/certification required to replace the steam gauges with electronic displays.

If you don’t know, but know someone who does/might, then I would be most grateful for a pointer in their direction.

Many thanks in advance,

Lou

[stankou]

Hi Lou,

At first, contact Piper to have the list of STC available in your aircraft.

then, 2 ways possible: It does exist, then you can contact the shop where the stc has been created. they will give you the price for the complete mod.

2nd way: It does not exist, so you must developpe your own project according the rules in force in your country.

[Bus429]

http://www.sandel.com/

You will require an EASA STC

[Lou DeCrosse]

Thank you for the replies - that's exactly the info I need. If I may ask a little more: If anyone had any idea of the costs of doing this without an STC, then I'd be very grateful for such information. I'm mainly concerned with the costs of design and the modification rather then the equipment - although if anyone had any recommendations regarding a very basic EADI/EHSI then I'd be delighted to hear their viewpoint....?

Lou

[Bus429]

Lou,

Find out if the mod you want, or a mod, has been accomplished/approved before on an EASA aircraft in an EU state after and before 28/09/03. If a mod was approved in a Member State prior to that date it will probably be "grandfathered". Have a look at the EASA web site, example below:

"EASA.A.S.01625 n/a Beech A36 Replacement of existing KI-
525A HSI system with new
KI-825 EHSI system
20/02/2006"

Follow: http://www.easa.europa.eu/ws_prod/c/doc/Design_Appro/STCs/STClist.pdf

From the STC website:
Supplemental type certificates - Lists
The following lists compile EASA Supplemental Type Certificates issued since 03/06/2004 by EASA.
'Grandfathered' STCs for which the agency assumed responsibility on 29/09/2003 and issued prior to that date are not included at this time.
Please note that the list is not yet comprehensive and will be frequently updated.

[Vortechs Jenerator]

I'd also consider are the replacement instruments self contained?

Do they require other computers/symbol generators to drive them or do they take information from what is already delivered to the back of the instrument panel?

[Bus429]

Sandel do direct replacement.

[mono]

This lot do very cheap EFIS.

You won't be able to use it as a primary display but you MAY be able to put it in the RH seat.

http://www.dynonavionics.com/docs/company_aboutus.html

They apparently have CASA (aussie) approval as secondary instrumentation.

[Lou DeCrosse]

Sandel/Vortechs - ok, that sounds the route of least resistance. I am guessing it's a 'one out, one in' replacement with no certification required for the Sandel option then? (hoping and praying for a 'yes'......).

Problem with the EHSI/EADI option is the wiring, extra boxes and gubbins they need - with the consequent requirement for ADO design and certification

mono - Thanks for the info on the Stby instrumentation - that could be a nice option too and one I hadn't considered.

Extremely grateful for the advice all :-)

Lou

[Bus429]

Even direct replacement has to be covered by an STC; it is a change(modification).