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Extra 400 upgrade project - call for advice

Hello everyone

After a few weeks browsing this forum I am very impressed with the amount of knowledge and real world experience here.
I would like to ask you to help me with an ambitious project already briefly disclosed on the thread regarding engine shipment.
Comments, ideas, etc… most welcome, and thank you!

My “new” plane is an Extra 400. It is N-Reg. and has 1200 hours on it.
The engine a TSIOL 550C is on its way to Canada where it is going to be rebuilt (repaired in FAA-speak) but not overhauled.
Should I dump the (12!) Champion fine wire plugs and go Tempest?

The prop has been sent to MT for O/H and will soon be back with new blades (Scimitar style) and the new reinforced leading edges. This will be installed under a 337 form.
The airframe will be thoroughly inspected for any wear and “real-world” life limits of parts.

Hydraulics will be refurbished and lifetime (teflon coated) hoses will be installed.
We have asked Beringer to consider using this project for certification of their nice wheel/brake system. Answer pending.

The instrument panel is being redone around a Garmin G500 / GTN750. The goal is maximum reliability, so we are looking at removing everything pneumatic and CRT based. My vision is to not buy more than the necessary number of certified devices, hoping that the FAA will (in 2017) allow experimental avionics as secondary devices.
So the second Nav/Com is not a GTN but rather the GNC225A (no GPS).
We are keeping only one transponder (mode S) and preparing for a future ADS-B upgrade.
The audio panel (GMA340) is replaced by a GMA35 remote mounted one.
The G500 has the GAD41e interface for the autopilot, which allows us to remove the STEC55X’s two remote devices and lets the g500 set the climb and descent parameters for it.
No synthetic vision and no terrain on the G500
A JPI EMD930 primary engine monitor will be installed.
Would you spend $500 on an integrated CO detector?

Provision is made for a semi permanent installation of a full size iPad with a $$ertified (ouch) USB power outlet for it in the panel.
This will run Garmin Pilot, be interfaced via Garmin FlightStream 210 and offer synthetic vision.
I was very upset to find out that Garmin wants me to pay twice for NavData – once for the G500 and once for the GTN750… That’s $ 1000 per year using the PilotPak.

So! What else would you do? What would you do differently? Thanks!

LSGG, LFEY, Switzerland

I would spend the money for the CO detector. Having had one probably saved my bacon once, in a few years old, well maintained, modern aircraft (maintenance screw-up)

Assuming you will be flying IFR:

Clearly you are on a budget, so saying go G600 with SVS and TAWS, and get a traffic avoidance system, are not what you are after…

So:
Keep any DME you have in the existing panel.
i would add the ADL-120 data link for weather. 2k well spent.
I would consider a used GNS430 instead of a nav/com so you have a second GPS, not just a nav/com
Only replace the audio panel if you need the space, spend the money on the ADL-120 instead.

Biggin Hill

Should I dump the (12!) Champion fine wire plugs and go Tempest?

I would suggest measuring the internal resistance. If it is ok stay with the Champion plugs and replace them once the resistance gets out of limit at annual.

Would you spend $500 on an integrated CO detector?

How is the cabin heat operated on this water cooled engine? If the cabin is heated with the liquid coolant like a modern car probably no need for the CO detector as in air cooled engines where a simple exhaust leak can discharge CO into the cabin.

www.ing-golze.de
EDAZ

My CO incident was the result of the cabin air intake hose coming loose and dropping down to next to the exhaust stack. It would have been identical if the engine had been watercooled.

But this is a good point – if the air intake is not going through the engine compartment, a CO detector is not really needed.

Biggin Hill

Cobalt wrote:

I would spend the money for the CO detector. Having had one probably saved my bacon once, in a few years old, well maintained, modern aircraft (maintenance screw-up)

Assuming you will be flying IFR:

Clearly you are on a budget, so saying go G600 with SVS and TAWS, and get a traffic avoidance system, are not what you are after…

So:
Keep any DME you have in the existing panel.
i would add the ADL-120 data link for weather. 2k well spent.
I would consider a used GNS430 instead of a nav/com so you have a second GPS, not just a nav/com
Only replace the audio panel if you need the space, spend the money on the ADL-120 instead.

Thanks Cobalt. I am on a budget of course (who isn’t) but absolutely wanting to do it right, once and for all.
SVS is planned – on the iPad with Garmin Pilot.
DME will stay
TAS (Ryan 9900 aka Avidyne TAS 600) is existing
I have sold my GNS430 and 530 to improve reliability. I did not go for the WAAS upgrade of the GNS because I wanted brand new electronics (switches, knobs, display, etc…) GMA340 also sold.
(My backup GPS is the FlightStream, displaying on the iPad. It is not certified but who cares…)
The central so-called “avionics stack” will have the GTN 750, the JPI EDM 930 and the GNC225
ADL-120 is on my shopping list, but my question with… Sebastian is still unanswered: how do you connect an ADL to an iPad if there’s already a FlightStream using the WiFi link. Do I have to reconfigure the iPad every time I use the ADL?

Sebastian: thanks for your advice too.
To answer your question:
There is an electrical heater in the air circuit, but the risk is definitely from another corner: cabin pressurization uses the turbo, so there definitely is a risk of CO contamination.

LSGG, LFEY, Switzerland

More questions! Can anyone help me answer the following airworthiness quiz? FAA rules!

While upgrading a panel, am I correct to consider that the following are minor modifications requiring only a logbook entry?

1) relocating backup instruments (from original 6 pack) to make room for G500
2) removing annunciators rendered obsolete by the presence of the G500 which is installed under STC
3) moving an annunciator group higher to make room, with visibility from pilot seat not materially different
4) moving a switch from its original location to another one
5) removing instrument panel parts that have become useless as a result of the panel upgrade, when said parts played no structural role apart from carrying the instruments and switches that were (re) moved

Thanks!

LSGG, LFEY, Switzerland

All permitted panel changes are clearly stated in the G500 STC installation manual. This includes where the standby instruments can go. There are strict limits in the STC on how far you can go in changing the panel structure and at what point you need separate engineering approval (DER 8110-3) if you want to replace a panel section rather than using the adaptor plate. The supplying/installing Garmin dealer should discuss all of this with you as part of the planning stage.
Warning lights (red or Amber) which have a position shown in the flight manual (perhaps in the emergency procedures section) will normally require re-approval if being moved. This isn’t a minor change log-book entry but a Major Alteration on a Form 337 using approved data, so again, an 8110-3 (unless you can access an FAA FSDO who will sign the 337 approving your referenced data). The requirements for Nav annunciators is covered in the GNS or GTN STC and the G500 meets the requirements for LPV annunciation, so no additional ones required.

Avionics geek.
Somewhere remote in Devon, UK.

I concur with Cobalt – CO2, ADL120, keep 430W as backup.

Additionally, I chose to install back-lit instruments lights – no more ugly little posts sticking out – and as many yoke switches as I could think of. I have: AP disconnect, CWS, GA, PTT, (all original), GTN750 frequency flip-flop, Traffic cancel and Transponder Ident. All saves reaching up to the panel sometimes. I also installed undercarriage repeater lights so a bulb failure wouldn’t result in a minor emergency.

Bear in mind with the remote transponder ( and audio panel if you choose), if the 750 goes down you lose control of the transponder and audio panel as well. I chose to keep the GTX 330 but have the 750 configured to control it, so I can chose which method to use.

Hope this helps.

Spending too long online
EGTF Fairoaks, EGLL Heathrow, United Kingdom

Thanks wiggylamp. I’ve found an outdated version of the install manual and went through it. Very useful.
It looks like I will need a 337 anyway because we need to replace the sheet metal panel in order to move the backup instruments.
Just wondering: do you think that moving the annunciators a few inches up or down and moving the landing gear cluster similarly will make the approval harder (assuming I provide proper engineering drawings of the before/after situation)?

LSGG, LFEY, Switzerland

Wigglyamp and I have disagreed on the need for a DER 8110 route in the past

He knows the regs well and obviously I won’t say you should contravene what an STC says.

But the need for a DER 8110 route (or indeed a Major Mod at all) is grossly overstated on the European avionics installation scene. When you speak to US shops you get very different views to European shops. This is partly due to the great difficulty of doing Field Approvals in Europe (the NY IFU is nonresponsive) which leads to using the DER 8110 route because it sidesteps any need for an FAA (FSDO) approval, but it loads a lot of cost onto the customer. The installer can however use the design data for future work…

Most mechanical work on unpressurised aircraft is adequately covered by AC43-13-2B but some European installers won’t accept that. For example I have been asked to pay about 2k for a 8110 covering the mounting (with some screws!) of an Avidyne TAS box which nobody in the USA (and I have been in contact with loads of people out there doing avionics) would ever suggest should be done as anything other than a Minor Alteration IAW AC43.

Other than as mandated by STCs etc, when it comes to RHS instruments, you can install nearly anything provided it is TSOd, there is no autopilot connection from it, etc. Most RHS stuff (in a single pilot plane) is in the “monitoring” category. The reason there must be no AP connection is that such a connection would require a change to the AP AFMS and that makes it a Major Alteration. I went through this on this project which was processed by a senior FSDO inspector and that job was absolutely “gold plated” in paperwork terms.

You cannot remove anything which is listed in the TCDS, unless the replacement is STCd as “primary”. Etc. This catches out people fitting stuff like EDM700, in some cases.

Regarding EASA-reg aircraft, I am sure the situation is more complicated

It looks like I will need a 337 anyway because we need to replace the sheet metal panel in order to move the backup instruments

Very unlikely unless somebody is heavily gold-plating.

You need to be clear about what a 337 is. A lot of them get generated without any understanding – see e.g. here And some are outright bogus – written out for the file and never sent anywhere. A bit like me giving you a share certificate for a 10% share in my business but never sending the paperwork to the company registrar (I have seen that done in the aviation business, too)

A 337 is a cover sheet for a Major Alteration. If what you are doing is covered by e.g. AC 43 (above) then it may be justifiable as a Minor Alteration and then you don’t need a 337. A 337 has to be supported by various data. The above link (my EHSI installation) covers the options.

Administrator
Shoreham EGKA, United Kingdom
78 Posts
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