Minimal Compliance with 91.205 for IFR

[Bcone1381]

FAR 91.205 says that for IFR an aircraft must have all the VFR day instruments (airspeed, altimeter, compass, engine instruments) plus a comm radio, a navigation equipment, attitude indicator, and Turn Coordinator, clock and electrical system.

In order to minimally comply with intent of 91.205, it appears that one could install a single EFIS display like a GRT HXr, plus remote radios and xpnder (which allows the tuning of remote radios) plus a separate turn and bank indicator and the EIS package.

It provides all necessary engine instruments, control of nav and comm radios, and all the flight instrumentation.

If one has to push a button to see the Engine instruments, is he still in compliance?

Am I missing something?

[BobTurner]

Nope. You can display engine instruments across the bottom of the screen, no button pushing. And you don't need a turn coordinator since the HXr will display rate of turn. But, you should ask yourself if it is wise to fly in IMC where the failure of a single box (HXr) could leave you in a very bad situation. Alternator, regulator, battery failure - same question. Is there more than enough one nav source?

[terrykohler]

In the "old days", the electric turn coordinator provided a level of backup to the vacuum driven instruments, i.e. failure of one would not result in failure of the other. Keep the wings level (or limit turns to standard rate) and use the altimeter and a bit of the VSI to hold altitude or establish a steady climb/descent.
Today, there are plenty of battery supported mini EFISs (Garmin G5, GRT Mini, etc.) to provide backup beyond your electrical system.
What I'm not seeing in your proposal is an adequate/TSO'd navigation system. While you might be able to get by legally with a single VOR, this becomes less rational as VORs continue to get decommissioned and are supplanted by GPS fixes. Think certified WAAS GPS.
As someone who is just now seeking an instrument rating or already has one with minimum time/experience, perhaps the best question for you to ask is "how do I maximize capabilities at the least cost" rather than "what's the least equipment I can get by with".
Terry, CFI
RV9A N323TP

[jrs14855]

In the "old days" it was a turn and bank, not a turn coordinator. The late Bob Buck, author of Weather Flying and North Star Over My Shoulder, taught himself instrument flying in a Pitcairn Mailwing with just a turn and bank. He climbed up into the clouds and flew a cross country to a destination where the weather was better. No radios involved.

[Bcone1381]

Thanks Bob, thats the kind of information I am looking for.

Terry, I asked a hypothetical question to help me understand todays regulatory environment. My question is an effort to accurately understand and apply the FAR's in todays experimental amateur built aircraft certification environment.

I start my planning by ensuring that the basics are installed, then add the backups that I feel are prudent for me. After that the electrical system gets designed.

I have been out of the GA industry since about 1989, but have been using IFR certified GPS that uses RNP criteria (Not WAAS) in a different segment of the aviation industry since the early part of this century. Trust me, that regulatory arena has little resemblance to what we are doing with amateur built sport aircraft.

I don't fully understand the application of the 1989 regulations to the 2017 experimental aircraft industry segments and am thankful for your mentorship.

By asking the question it helps me to begin to understand what equipment my FAA friends expect me install to file IFR in VFR & MVFR conditions. Sure would be nice to complete a X/C mission in comfort when the water is not all that bad, but not all that good...do you know what I mean?

Regarding the TSO'd navigation system...I included in my hypothetical senario a nav radio. I did not include a GPS on purpose, because my past attempts trying to sift thru opinions about what is approved for Enroute phase and the Approach phase made my head spin.

To everyone...Since Terry asked, School me please. Will a WAAS GPS (like the GRT Fly-Safe 2020 product) fulfill the FAR navigational requirements for IFR in the enroute and approach phases of flight as long as it is giving data to a suitable software/display?

Additionally, will an iPad connected to an iLevel AW via bluetooth using one of the flight instrument panel applications that provides all of the required instrumentation meet the FAR 91.205 criteria?

Thanks

[BobTurner]

Originally Posted by Bcone1381

Regarding the TSO'd navigation system...I included in my hypothetical senario a nav radio. I did not include a GPS on purpose, because my past attempts trying to sift thru opinions about what is approved for Enroute phase and the Approach phase made my head spin.

To everyone...Since Terry asked, School me please. Will a WAAS GPS (like the GRT Fly-Safe 2020 product) fulfill the FAR navigational requirements for IFR in the enroute and approach phases of flight as long as it is giving data to a suitable software/display?

Additionally, will an iPad connected to an iLevel AW via bluetooth using one of the flight instrument panel applications that provides all of the required instrumentation meet the FAR 91.205 criteria?

Thanks

1. A nav radio (VOR/ILS) does not need to carry a TSO.
2. A GPS radio used under IFR must meet the standards of TSO 129 (non-Waas) or TSO 145/146 (WAAS). This is much more than GPS accuracy, it includes a comprehensive data base, even rules regarding management controls on software writers. New TSO 129 boxes are no longer sold (used boxes are available). TSO 129 boxes can only be used if VOR is also available, TSO 145/146 boxes can be used legally with no backup. Short answer, the Fly Safe has no database, is not TSO'd under 145/146, it cannot be used for ifr navigation.
3. I suspect a panel mounted iPad fed by an iLevel meets the letter of the EAB law. But is it wise? IMHO, maybe for the #4 backup.

[rzbill]

Originally Posted by Bcone1381

By asking the question it helps me to begin to understand what equipment my FAA friends expect me install to file IFR in VFR & MVFR conditions. Sure would be nice to complete a X/C mission in comfort when the water is not all that bad, but not all that good...do you know what I mean?

Yep, I do know what you mean. IFR in MVFR is usually quite benign. BUT, it has bitten me and I imagine others. I have finished a flight that began and nearly completed in MVFR but wound up shooting ILS to minimums because the weather deteriorated (unforcasted) while I was on approach.

As Bob mentioned, the approval nature of IFR GPS navigators is not just the GPS accuracy. It also (very importantly) includes the navigation database and its revision control.

My advice would be to not go minimalistic on the instrumentation. Be ready to fly to minimums since it can happen unexpectedly. Be ready for stuff to fail because it will.

[Bcone1381]

I would like to stay focused regulatory requirements, and stay away from opinions about what is prudent and safe.

You have helped me understand the flight instrument engine instrumentation requirements for IFR. Lets further direct what Bob Turner said about IFR GPS.

The navigational expectations and requirements that the FAA mandates for us is a TSO 145/146 GPS. Does the experimental marketplace have a host of GPS offerings that dont legally allow GPS IFR operations? Here is a post from Dynon I just came across.

http://dynonavionics.com/cgi-bin/yab...num=1362597418

Some of the key words in the Dynon Post is
-Use GPS for Primary Navigation requires a TSO 146 unit.
-An approach must be flown from an FAA approved database
-Manual waypoint entry is no authorized instrument approaches.

So, lets conclude that a certified WAAS gps with a nice software/display package adds no legal IFR capability...it just adds a colorful, safe, effective, accurate navigation source. But if one used it, one would be (willfully?) non-compliant with the FAR's.

What are the IFR GPS products that are being used by everyone? Seems like Garmin 635 turns up as an option a "low end" option.

[Auburntsts]

Originally Posted by Bcone1381

The navigational expectations and requirements that the FAA mandates for us is a TSO 145/146 GPS. Does the experimental marketplace have a host of GPS offerings that dont legally allow GPS IFR operations?

Yes -- I think all of the major EFIS manufacturers provide a VFR WAAS GPS solution as part of their basic EFIS packages. Plus there's lots of portable options.

So, lets conclude that a certified WAAS gps with a nice software/display package adds no legal IFR capability...it just adds a colorful, safe, effective, accurate navigation source. But if one used it, one would be (willfully?) non-compliant with the FAR's.

No, as long as you it used only as a backup to your primary NAV (ie VOR/LOC/GS, etc) for the purposes of increased situational awareness. But you couldn't use it as sole source enroute Nav or to shoot any GPS approaches.

What are the IFR GPS products that are being used by everyone? Seems like Garmin 635 turns up as an option a "low end" option.

I would say that there's still quite a few WAAS and Non-WAAS GNS 430/530s still in service. WAAS gives you lots more capability so I'd steer clear of a non-WAAS box. On the new side, the GTN 650/750s are probably the biggest sellers as most want the radios the 625/635s lack.

[snopercod]

Originally Posted by Bcone1381

Seems like Garmin 635 turns up as an option a "low end" option.

$10,600 is "low end"? I must be way out of touch... I'm in the same position as you and would like to upgrade my VFR panel to "minimalist" IFR. I guess I could be "legal" with a cheap VOR but don't see the point. The cheapest GPS that I know of would be a used GNS-430W for around $8,000. I just can't afford that.