IR Training: Partial Panel

saracelica

saracelica

Pattern Altitude
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saracelica
Evidentally I'm gettign the feel for this IR training.:) Got the ATC stuff nailed down and so we're moving on to partial panel. To help myself out I figured I'd ask you guys/gals this question so I don't feel too stupid.

When my CFII covers up one (or several) of the instruments is that considered an "emergency" that typically I would let ATC know about? What typical instruments get covered/failed?
 
saracelica said:
When my CFII covers up one (or several) of the instruments is that considered an "emergency" that typically I would let ATC know about? What typical instruments get covered/failed?
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If it happened for real, yes. There is guidance on this in the AIM (I don't have mine handy but you can look it up) and ISTR there is a regulatory requirement to report instrument failures. In training, the only time I've said anything is if I was wandering off course and the controller mentioned it; I'd just say "roger, 8JT is partial panel".

Usually partial panel means the CFII covers up something that you could lose as a result of a single point failure, either a single instrument or two that both rely on e.g. the vacuum system (AI and DG). For the checkride, my DPE covered both my AI and my HSI even though there is no single point failure that could cause me to lose both. Since I knew that in advance, I trained that way too during checkride prep.
 
Partial panel generally involves covering up the vacuum-driven instruments (AI and DG). The goal is to realize the turn coordinator helps to back up the AI and the magnetic compass is the primary heading indicator, albeit not ideal due to its errors. In the real world, if you were to lose any of the required instruments for IFR flight (and the AI and DG qualify), you would let ATC know; if anything, they may give you a no-gyro approach or help line you up better on the final approach course. Also, if they were to fail in the real world, you'll want to cover them up to avoid conflicting information.
 
What the others have said. I've also notified ATC when the GPS wasn't working, since I was filed /G at the time, making it a required piece of equipment.

One of the things with a standard six-pack is that covering up the instruments is totally unrealistic. In actuality, they slowly start drifting off, and the real trick is recognizing as soon as possible that the parts aren't adding up to a proper picture. That's where a simulator can be helpful, because they fail in a more realistic manner.

This is where knowing your systems can be helpful. You may have backup vacuum, or a backup electrically driven AI, and would want to know how to use those and revert your scan to them. I think an examiner choosing unrelated instruments to fail is kind of poor, but then I'm not an examiner.

Kent tells how his instructor kept failing things until about the only thing he had left working was the compass.

Failures in a glass panel are altogether different. In that situation, it automatically puts a big red X over the failed instruments (or the entire screen goes dark) so recognition isn't a problem, but you will now be looking in unfamiliar places for the backup instrumentation.
 
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The interesting approach I did was when I came out of having my head down for an unusual attitude and found the VSI and Altimeter covered. I thought this was an attempt to simulate a static failure but it turns out the instructor was just one set of gauges off on his placement of the no-peekies.
 
You want to let ATC know because it could very well affect how they handle you down the road. If your AI has failed then obviously they're going to do whatever they can to get you out of IMC or to keep you from going into IMC. If your DG is failed you'll most likely get no gyro vectors, although if you have a working IFR GPS they could just send you direct. If you want to try something different, find an airport that has a PAR and request a no gyro approach for training. Challenging stuff for both you and the controller.
 
You could always pull the chute handle and hope it works.
 
ALL IFR is partial panel.

You can only cross check perhaps 2 instruments at a time - and those will always end up being the HSI/DG/T&B and the VSI. If you are not changing bank angle, course or altitude - you have nothing to worry about.

Think about it for a moment - to change course you need lateral axis shift and to change altitude you need rate.

Literally everything else is gravy. . . . meaning additional information that proves nothing to the other 2 or 3 instruments. . .
 
flyingron said:
The interesting approach I did was when I came out of having my head down for an unusual attitude and found the VSI and Altimeter covered. I thought this was an attempt to simulate a static failure but it turns out the instructor was just one set of gauges off on his placement of the no-peekies.
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So which of you pointed out the peculiar partial panel first?
 
azure said:
Usually partial panel means the CFII covers up something that you could lose as a result of a single point failure, either a single instrument or two that both rely on e.g. the vacuum system (AI and DG). For the checkride, my DPE covered both my AI and my HSI even though there is no single point failure that could cause me to lose both. Since I knew that in advance, I trained that way too during checkride prep.
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Your DPE probably figured it would be good to know if you could handle PP in a slightly less equipped airplane. Like you, in my airplane the only gyro running on the air pump is the attitude indicator but the air driven one is my backup to the electric one. I configured it that way because the (original) air powered horizon feeds the autopilot and if it starts to roll over it should be obvious on the electric one sitting on top of the HSI. To get a true feeling of PP I have to cover both AIs plus the HSI and turn off both GPS navigators (one of which has battery backup) and the MFD since I can get heading and course info from all of them (well actually the portable GPS only gives track but that's plenty good enough).

I've always been a little concerned about dealing with a dying attitude indicator shortly after takeoff into low IMC. From some experiments in a sim I concluded that if you're not scanning really well and there's very little room for error at that point.
 
The actual Task is "Approach With Loss of Primary Flight Instrument Indicators." What that means depends on what you've got in the aircraft. If you have an old-fashioned 6-pack panel with vacuum-driven AI/HI, that's what you lose. If you have a G1000 system, it usually means losing the PFD and going into cross-cockpit reversionary mode on the MFD, but it could mean losing the AHRS (a much more serious problem). When I train folks, I try to give them every possible single-point failure their aircraft is reasonably likely to have. That's usually a lot more extensive than what they'll get on their practical test, but it prepares them for reality, not just the test.
 
And YES, you should tell ATC that you are on secondary instruments. They'll generally give you gentler manuevers, give them earlier if they can, and be willing to tolerate your sloppiness.

NEVER be afraid to TELL ATC what you need to be safe. If you're in turbulent air and it's taking all your effort to keep the plane upright, tell them so. Tell them unable if they give you instructions you can't execute. Ask for a block altitude and tell them why. If it's weather (Ice or CB), don't let them paint you into a corner. Use your emergency authority if you have to.
 
gismo said:
Your DPE probably figured it would be good to know if you could handle PP in a slightly less equipped airplane. Like you, in my airplane the only gyro running on the air pump is the attitude indicator but the air driven one is my backup to the electric one. I configured it that way because the (original) air powered horizon feeds the autopilot and if it starts to roll over it should be obvious on the electric one sitting on top of the HSI. To get a true feeling of PP I have to cover both AIs plus the HSI and turn off both GPS navigators (one of which has battery backup) and the MFD since I can get heading and course info from all of them (well actually the portable GPS only gives track but that's plenty good enough).
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Yes, that's what I would have to do too. I've never trained like that though, because the DPE was perfectly happy let me use the GPS and MFD, as long as I also used a legal primary nav source for course guidance (it was a VOR approach).

I've always been a little concerned about dealing with a dying attitude indicator shortly after takeoff into low IMC. From some experiments in a sim I concluded that if you're not scanning really well and there's very little room for error at that point.
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In IMC the AI is probably the instrument I use the least (well, about equal with the VSI). Mine has always shown a noticeable (though legal, <5*) bank even with wings level. The TC and HSI tell me if I'm turning, and the altimeter and VSI tell me all I need to know about my climb rate. Of course I'd have to treat an AI failure under IFR as an emergency, legally speaking, but practically speaking it would be nearly a non-event. During training I asked my first CFII to cover my HSI for partial panel because covering just the AI wasn't challenging at all. (Unfortunately, even that was like pulling teeth.)
 
You have to tell ATC when you lose an instrument. They may ask you "Do you require any assistance" and if you're VFR and you'll stay VFR you won't likely need any. But if you're hard IMC you're gonna have issues. That being said losing an instrument doesn't necessarily mean you're declaring an emergency, not until YOU say you're declaring an emergency.


I heard on the radio the other day an airplane that took off with a dead battery (he had to have it jumped) and he got into hard IMC (on an IFR flight plan, knowing it was hard IMC) and about 10-15 minutes later he reported he had to come back because of an instrument failure. He was vectored back (and he was asked if he wanted to declare, he declined even though at the time he had a rough running engine too. Luckily that cleared up) but no priority or anything just took him back for the ILS. Outside the FAF the battery finally died, along with all his navigation aids. He decided instead of slowing descending on the ILS heading to climb up and use a handheld. He finally declared an emergency and ended up needing a makeshift PAR approach because he was starting to get disoriented to the point he didn't trust the mag compass.

The lesson I learned: Be proficient in partial panel. Break the accident chain before it becomes scary. Always know where VFR is. Don't be afraid to declare an emergency. He would have gotten vectored to the FAF and slid down teh ILS before his battery died if he would have just used that word initially. But he didn't want the paperwork associated with it or to deal with the feds.
 
Z06_Mir said:
he got into hard IMC (on an IFR flight plan, knowing it was hard IMC) and about 10-15 minutes later he reported he had to come back because of an instrument failure. He was vectored back (and he was asked if he wanted to declare, he declined even though at the time he had a rough running engine too. Luckily that cleared up) but no priority or anything just took him back for the ILS.
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Given the earlier battery problem and an instrument failure (rough-runing engine too!), it makes no sense (although it's unfortunately common) that he would refuse the priority handling a simple declaration of an emergency would give him.

OTOH, his judgment in taking off into IMC with a battery that had to be jumped (unless maybe when he came to the airplane he saw the master switch had been left on) is consistent with his refusal to declare.
 
Z06_Mir said:
The lesson I learned: Be proficient in partial panel. Break the accident chain before it becomes scary. Always know where VFR is. Don't be afraid to declare an emergency. He would have gotten vectored to the FAF and slid down teh ILS before his battery died if he would have just used that word initially. But he didn't want the paperwork associated with it or to deal with the feds.
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Sorry, pardner, but that's most assuredly not the big lesson to be learned. The lesson here is if it ain't fixed, you don't fly it. Launching in "hard IFR" without a working alternator is just plain stupid, and beyond that, I leave it to Forrest Gump.
 
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