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Partial Panel Question: IFR checkride with multiple EFIS screens and tablet

DeltaRomeo

doug reeves: unfluencer
Staff member
Hypothetical question and looking for discussion regarding IFR checkride.

Background Info:
My panel right now (picture). The EFIS screens all get power from a single bus, and share a single ARHS. iPad mini running Garmin Pilot talking via Bluetooth to a Garmin GLO GPS antennae up on the dash (gives me the blue dot on the approach plate). Both the iPad and the antennae use their own battery power (completely independent of the aircraft).


The question:
If I replace the GLO antennae with a GDL 39 3D (which gives my iPad attitude info), and the checkairman covers up parts of my PFD for the partial panel work, can I use the iPad Mini's 'panel'? It’s completely independent of the aircraft, uses its own battery power, and adds a 2nd AHRS unit to the equation. If the whole panel goes dead in the clouds I have a way to know where ‘up’ is.


Example off the web of this setup in use:

dsc01519.jpg


Will I be allowed to use this, or will they say, “Please turn off the iPad”.

Question #2:
Can I just look across the cockpit to the passenger’s PFD and use that, or will they cover it up too? If not, I don’t need the GDL 39 3D.


Discussion appreciated (especially from CFII folks).
v/r,
dr
PS: I might need a IFR checkride here in a couple months. Anyone around N.TX qualified and willing to do the ride in my RV-6?
 
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The basic point of partial panel, using your example, is to fly with certain instruments missing from the equation. If your primary instrument for X goes south, how do you use the other instruments available to you as secondary indicators for X? So, I'd expect the iPad will likely go off as well if an attitude indicator is displayed and that's the instrument being removed from the system.

Of course, in the real world having redundant info is great, assuming its accurate. The GDL39 could be useful in a pinch when things really go south but it's not a primary device to be sure.
 
That is a discussion to have with the DPE you intend to use. The concept of 'partial panel' is very different in the world of EFIS's.

With your panel, he could fail the EFIS (both screens) and have you do a GCA (since you have no Approach Nav) using the steam gauges and the TT ADI.

I'm currently flying with a student in his RV7A with a dual screen Dynon system with dual AHRS. The worst failure is one screen goes blank - but either screen gives you a 'full' panel (and now you can even show it as a 6 pack if you want :eek:). He doesn't have any 'backup' instruments (other than dual screens and dual AHRS). I have to have my discussion with the DPE soon!
 
Well anything less than flying a back course ADF approach with only a turn and bank (no turn coordinator) has got to be cheating...

As for your specific question - I am curious, too how the FAA views this question and will be interested in the answer(s).
 
That is a discussion to have with the DPE you intend to use. The concept of 'partial panel' is very different in the world of EFIS's.

With your panel, he could fail the EFIS (both screens) and have you do a GCA (since you have no Approach Nav) using the steam gauges and the TT ADI.

I'm currently flying with a student in his RV7A with a dual screen Dynon system with dual AHRS. The worst failure is one screen goes blank - but either screen gives you a 'full' panel (and now you can even show it as a 6 pack if you want :eek:). He doesn't have any 'backup' instruments (other than dual screens and dual AHRS). I have to have my discussion with the DPE soon!

That's how my 9A is setup, I'm interested in your answer...
 
Best to just ask the examiner...

Most of them will discuss your particular airplane's capabilities and give you a "likely" scenario.

This has to be more and more common with the number of glass panels out there these days.
 
Doug,

Dont forget to have a backup for your approach plates.

I know you have an ipad for them, but you may want to have the G3X also for a backup if he/she turns off the ipad on you.

Or just have hard copies for the ride.
 
As suggested I would check with the DPE. I believe that this one is very DPE dependent. I know on my check ride I flew a 172SP with dual vacuum pumps. (six pack system) My instructor talked to the DPE and they decided that a complete vacuum system failure was unlikely so he let me use the DG with a attitude failure only. I was prepared and capable of a Turn coordinator and compass only flight but my check ride ended up being much easier than most of my training.
I have always wondered how they fail a EFIS for the check ride.
 
Doug,

Like someone else said it would be good to ask a DPE, how they would simulate it. I also suspect you will get a different answer from every DPE you ask.

Generally partial panel simulations are based on the loss of a system or component, in the old days a vacuum pump failure for instance or an electrical anomaly.

For more modern instrument display systems it is more likely they would simulate the failure of a AHARS sensor or a display failure. So it would depend on how a particular panel is designed what the 'partial panel' would look like. Variables are things like are displays driven by the same AHARS? are they powered from the same buss? Is there a backup power supply for one of them?

If you had an Alternator failure what would you consider turning off to extend your battery life until you could get on the ground?

Since your plane does not have a old school steam backup instruments, the DPE is going to have to leave you something to work with. It may well be it iPad so the GDL39 might be a good idea. Just simulate declaring an emergency ask for radar vectors to the nearest suitable airport and a ASR approach:)
 
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As others have said the DPE who does your check ride should give you the flight scenario including the partial panel portion. It's your check ride, the more questions you ask the DPE the better prepared you'll be, even practice the check ride scenario the DPE gives you with your CFII.

I would say a G3X total failure and use the iPad for its attitude/heading is the worst possible scenario to use. A screen failure on the G3X would be next best using the right side for attitude/heading.

It's crazy the functionality and redundancy in our experimentals these days!
 
It is an interesting problem today, with the wide variation in equipage across platforms. The instrument rating doesn't limit the pilot to glass cockpits with redundant displays, etc, so shouldn't the test address skills for the minimally equipped airplanes?

The practical test standards requires the applicant to provide a suitable airplane for the test and describes the requirements for both the airplane and performance of the test.

The practical test standards address this, page 7.
 
page 8 of the instrument PTS provides some guidance to this question, 'What constitutes partial panel with an EFIS?'

If the right side PFD is totally independent of the left (air data computer, alternate power buss) then using that would seem to be fine. I also see no issue with the iPad.

But as everyone says, talk with the DPE. As you know, examiners ride in EAB aircraft at their option. Make sure to ask about that, too.
 
The purpose of demonstrating partial panel competency on an IFR check ride is to determine if the applicant is able to safely complete a flight after loss of his primary instruments. If you have 2 or 3 ways of showing the same thing, then as an instructor, I would expect the pilot to demonstrate competency in using the least capable of these different systems. If all you are left with (like in the'old' days) is needle/ball and airspeed, then so be it. If you have a complete secondary backup built in to the airplane that has its own AHRS, NAV system, etc...... then so be it. If your backup is an iPad, I'm sorry, but I would fail that on you too and expect a safe outcome with what you have left. The iPad is not part of the required onboard equipment for IFR flight - except for charting, and you'd better have a backup for that too.
 
Isn't your IFR ticket good for you to climb into airplanes other than your own? Seems to me that the test standards need to be what they need to be, to insure you're competent in any IFR certificated airplane.
 
It will be interesting to hear one or more examiners' answer.

My instruction had me respond to "system failures" rather than individual instrument failures. An example is: "if you lost your vacuum pump, you will eventually lose all vacuum driven instruments. what is your backup and how do you maintain safe flight?" On a traditional "six pack" that scenario will fail both the attitude and directional gyro. The backup then becomes turn-n-back and compass.

With the fully glass system I now fly, the failures I've been assigned are "any shared component failure". We also discussed the hypothetical full electrical failure.
 
One thing to think about and consider in reference to your question, please remember that although the Apple ipad is a good tablet product with versatility, it was not a purpose built product for aviation, and as such may not the reliable piece of equipment for the type of IFR issue that you have been contemplating...

Just a thought.

Victor
 
I feel the issue is not so much can you fly this plane safely in IFR, but are you trained enough to save your butt if multiple things go wrong. That said, I'd say no redundant EFIS, no iPad. I'd want to see what I could do with bare minimum equipment.

Flying VFR, once had an instructor cover everything on the panel, and I mean every instrument and every radio (just draped a sectional chart over the eyebrow). Was on a cross country and he said - make it back to home staying at relatively same altitude and airspeed. I felt it was great training. Same applies to IFR - see what you can do and train with minimal instruments.
 
given the picture of your panel, if I were the examiner, you would be flying with all the screens dark, the IPAD off. since you have more than you need with the backup alt,airspeed, and attitude. just me, but if you cannot fly an approach using those three, you have no business flying the clouds.

bob burns
RV-4 N82RB
 
given the picture of your panel, if I were the examiner, you would be flying with all the screens dark, the IPAD off. since you have more than you need with the backup alt,airspeed, and attitude. just me, but if you cannot fly an approach using those three, you have no business flying the clouds.

bob burns
RV-4 N82RB

Here is Doug's panel:
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Doug's plane is a 3 screen G3X system with one AHRS. He has no independent backups. If he loses the single AHRS, he is in trouble.

Doug, I would not rely on the GDL39 3D AHRS to keep me alive as a primary backup. As a backup to the backup maybe but definitely not as the primary backup.

I highly suggest you look at installing at a minimum a second GSU 25 AHRS. I would also definately connect up the optional backup RS232 serial link from it to your PFD2.

This will give you screen redundancy (which you have now), AHRS redundancy but still won't save you from a common mode failure that might bring the entire G3X system down.

Of course you do have a partial backup in the GX pilot that does give limited AP functions even if the G3X system goes south. I would practice this failure mode to understand what you would be left with.
 
Have a plan and understand your systems

You are smart to ask the questions, not only for the checkride, but for the real world.

It starts with "What would I do if...", and go from there.

In the steam gauge world of days past, if you lost all electrical you went to vacuum instruments. Lose vacuum and you go to electrical turn & Bank, or turn coordinator. Lose vacuum and electrical and... oh well.

In your case, lose one PFD, go to the other. Lose electrical, go to backup battery. Lose AHRS... use the ipad, or can you keep the airplane reasonably wings level with the GNS430 display of heading? Have you practiced that? In any case, how quickly can I reach VMC?

What if all your charts are on your ipad and it quits? How can you get the info for an approach? Use ATC? Use the GNS430? Maybe both?

If I were an examiner, I would give you just such a failure scenario, on the ground before you flew to understand how much you know about the systems and how you would deal with cascading failure.

One relatively quick solution to your backup dilemma might be to install a pictorial turn and bank where your clock resides.


Don
CFII
 
I sent a note to my DPE, explaining the panel, and offering to fly with him in t he plane so he could get familiar with the panel.

Here are his replies:
Hi Dennis, yes... I would like to fly with you in the airplane before the checkride... that's a good idea. The PTS says I have fail the primary flight instruments or the PFD if it's a digital cockpit. I'm not sure if the aircraft qualifies for the partial panel requirement since it sounds partial panel proof. I'll check in the morning and get back to you.

Hi Dennis, yes that airplane will work. I'll dim the primary and your applicant will fly off of the secondary. Ok? Ok!

So my student will have to suffer through looking at the right screen, instead of the one in front of him :rolleyes: He will have to reconfigure it to show the PFD in addition to the Map (and maybe EIS - his choice).

Note: his brother has a Dakota with 'steam gauges' and a 430. We have flown it a couple of times, and I told him we would be doing partial panel work in that airplane before he has my blessing to go IFR in that plane.

I wonder if the FAA will ever acknowledge the inherent differences between these types of panels, and require an endorsement to fly a 6 pack IFR if the rating was achieved in an EFIS only aircraft. Not suggesting anything, just wondering...
 
Just a thought, but the iPad might be considered for situational awareness and not legal for partial panel. Just a guess.
 
Isn't your IFR ticket good for you to climb into airplanes other than your own? Seems to me that the test standards need to be what they need to be, to insure you're competent in any IFR certificated airplane.

The truth is the FAA is counting on pilots to use some common sense. It is legal to get the rating in a glass panel airplane with just a GPS and a VOR/ILS, then hop in an old 172 with a conventional six pack and shoot an NDB approach. Legal, but maybe not too wise.
 
The truth is the FAA is counting on pilots to use some common sense. It is legal to get the rating in a glass panel airplane with just a GPS and a VOR/ILS, then hop in an old 172 with a conventional six pack and shoot an NDB approach. Legal, but maybe not too wise.
Depends on whether one learned with an ADF or not!! :) Hard to get less complex.
 
Depends on whether one learned with an ADF or not!! :) Hard to get less complex.

My cfii experience is that pilots transition 'up' (to glass, gps) much easier than the other way. In particular, pilots who get the rating with a gps seem totally lost without it.
 
rules vs good judgement

As far as I can tell, the standard ifr 'waiver' for EAB (91.205) is very lax. There is no requirement for redundant power sources, etc. For non-EAB aircraft those details are usually found in the type certificate process.

That being said, I personally would not fly in IMC in an airplane where a single failure (AHRS box) would leave me with no flight instruments other than something based on an iPad. If necessary I would remove and sell one of the two 430's, and replace it with a GRT mini (plus battery), Dynon D-6 (plus battery), etc. And have cash left over.
 
As far as I can tell, the standard ifr 'waiver' for EAB (91.205) is very lax. There is no requirement for redundant power sources, etc. For non-EAB aircraft those details are usually found in the type certificate process.

That being said, I personally would not fly in IMC in an airplane where a single failure (AHRS box) would leave me with no flight instruments other than something based on an iPad. If necessary I would remove and sell one of the two 430's, and replace it with a GRT mini (plus battery), Dynon D-6 (plus battery), etc. And have cash left over.

No problem there-- I'd be happy to trade you a Mini for one of those 430s. :D

Sure it's "legal" to use an iPad as your backup in an emergency situation-- if you have it, and the only other option is screwing yourself into the turf, then use it! But, is it smart to rely on it as your sole backup? That's left up to your own judgement and plays a big part in establishing your own personal weather minimums. If I were an examiner, I'd discuss your systems in depth during the oral, and then ask you what your backup plan is when the single AHRS fails. Then we'd go try it on the checkride and see if it works. Can you get home using just an iPad? Let's try! A lot of examiners will just cover up your primary screen and have you fly on screen 2 or 3 for the test, which technically satisfies the PTS. But how close is that to reality? Reality says you're just as likely to have a failure of your single AHRS or power bus, and your airplane is not ready for that to happen in IMC.
 
I think that even Part 91 requires a backup for charts if you're using an EFB (iPad). This doesn't mean buy another subscription - just make hard copies of the charts you'll need from Foreflight, Garmin Pilot, etc., in case the iPad doesn't work.
 
What if my primary charts are those provided by the Garmin G3X (i.e., FliteCharts) and the EFB (iPad) IS the backup? Do I need a back up for the back up? And if so, how far down this silly road must we go?
 
Isn't your IFR ticket good for you to climb into airplanes other than your own? Seems to me that the test standards need to be what they need to be, to insure you're competent in any IFR certificated airplane.

You can say the same thing about the IFR pilots that have never flown glass.... The ticket does not specify which aircraft you fly, just like a Private Pilot or a Twin ticket does not specify a particular type of aircraft you can fly, as long as it's in the same class. That part is the responsibility of the pilot to ensure they have time in type for personal safety but not something that is required.
 
I am a DPE, RV builder, and do checkrides in EABs The comments here have been excellent. The DPE will have a written plan of action for the checkride, so there are really no surprises and your input and knowledge of the aircraft is an important part of the DPE constructing this plan. You should discuss the failure mode (such as simply covering the panel,dimming to zero, or pulling a breaker on the AHARS if your system will tolerate it, etc.) We certainly don't want to do anything to damage the system. I encourage all the glass/EAB folks to really consider backups and practice such before a real world emergency. This includes having the autopilot fly the plane directly from the rs232 data off a GNS430 or similar if the EFIS ouput to the AP dies. The IPAD type display while not suitable as a primary flight display can certainly save your bacon, but probably only if you already have that display mounted and configured. A real panel loss in IFR would end badly before you could fire up the EFIS style display.
 
My $0.02

Not a DPE, but I am a military equivalent. I have given instrument checks/ratings in all the above situations. Steam with "old standby" and that Partial panel takes some work.

Last aircraft was all glass, but had mechanical gyro backup (but I am sure you would get vertigo using it in IMC...5 feet from your face...you needed to lean to the center to fly off it!

Current aircraft has Full glass/EFIS to include an L3 Trilogy (full EFIS) backup...so we can't really do partial panel...Primary failure leads to backup.

I, for one, would like to see a language change going forward to say just that...no more partial panel, just primary and backup. If you are flying an older 172, backup = partial panel. TAA then backup = other EFIS. Part of the reason we have these great, multiple redundant systems is so we DONT have to fly partial panel.

I know your plane is EAB, but I would say, think like its certified...if the primary failed, COULD you certify the iPad installation? Not yet.

From many hours of actual instrument flying, and many failures, I would never want to fly IMC without some sort of fully redundant Attitude system (2 AHRS if one single AHRS CAN fail).

One last point. I fly IMC because I get paid to do it, therefore I am forced and paid to maintain my currency...STILL I occasionally fly in bad weather that reminds me I could still use more practice. Ask yourself a question and answer HONESTLY, how much will you fly IFR, how much of that will be IMC, how much will you practice, and will you remain proficient (not just current). The point is, there is a good chance you could be marginally proficient and end up in the clouds...get a good backup.
 
Good advice.

<SNIP> One last point. I fly IMC because I get paid to do it, therefore I am forced and paid to maintain my currency...STILL I occasionally fly in bad weather that reminds me I could still use more practice. Ask yourself a question and answer HONESTLY, how much will you fly IFR, how much of that will be IMC, how much will you practice, and will you remain proficient (not just current). The point is, there is a good chance you could be marginally proficient and end up in the clouds...get a good backup.

This reminds me of the advice I got from a friend named Bob Crippen. I think he was a Naval Aviator before he became a Shuttle Pilot. I've never forgotten that conversation.
 
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