Tips from my CFII checkride last Friday

MarkL

MarkL

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MarkL
I thought I would share these tidbits that came up during my oral discussion from my CFII checkride last Friday.

1) Marker beacons transmit on a freq of 75 megahertz.

2) FAR Part 95 covers MEA, MOCA, etc. FAR Part 97 covers an instrument approach.

3) If you lose all instruments and need to descend through a cloud layer, use the magnetic compass on a southerly heading. On the southerly heading, it will be real sensitive to direction change and you should be able to maintain that southerly heading as you descend.

4) if you lose radio comm, be sure to turn up the volume on all nav equipment in case ATC tries to contact you there instead.

5) The descent rate to maintain the standard 3 degree glideslope can be approximated with the following: ( Ground Speed / 2 ) X 10

6) The VSI is the best instrument to monitor when holding a GS descent as it will tell you the trend immediately, that is... if your descent rate changes, it will show this deviation before your GS needle does.
 
3a. Maintain heading with mag compass and ball centered(indicator, not an instrument). Keeps you from a spiral dive, and keeps the plane coordinated. Note; not a CFII, just a pilot of really primitive planes. If the compass is tilting, you're doing something wrong.
 
MarkL said:
I thought I would share these tidbits that came up during my oral discussion from my CFII checkride last Friday.


3) If you lose all instruments and need to descend through a cloud layer, use the magnetic compass on a southerly heading. On the southerly heading, it will be real sensitive to direction change and you should be able to maintain that southerly heading as you descend.
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Wouldn't a north heading work the same as a south heading? If not, why not?
 
I'll go review this again, but I believe that maintaining a constant south OR north heading minimizes errors.
 
TMetzinger said:
I'll go review this again, but I believe that maintaining a constant south OR north heading minimizes errors.
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I think so, too, but -- and I'm not certain of this -- aren't the errors all in the same direction on southerly headings?
 
I think he means the compass is livelier on the southern indications, and more likely to indicate a deviation before you get too far off. N lags S leads.
 
Ah, but it's just as sensitive heading north as it is south, it just leads in the wrong direction.

I can see where this might be easier on a south heading - "Hey, the compass just showed a massive turn to the right, I must be in a slight right bank". It doesn't really help you know how far you've turned, though, until it settles down, and it won't settle down until you stop the turn using the turn coordinator. There is NO way you can keep wings level with the compass. Let me rephrase. There's NO way _I_ can keep wings level with a whisky compass. Other pilots may be better at this.

So, to my mind - head south OR north. If the compass swings in ANY direction, level your wings with the TC, and then when you're wings level, look at the compass, and do a TIMED standard or half rate turn to get you back on heading.
 
MarkL said:
TC is inop. We are talking complete instrument failure.
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No gyros at all? I missed that, but I see it implied now. Interesting concept, and a good discussion.

An alternative I've often heard is to spin the airplane IF you know the cloud bases are high enough to permit recovery.

Hope I never have to choose between the two options - part of me thinks the energy in a spin might be less than in the spiral dive that might develop from trying to keep wings level using just the compass. I'd make my peace with God before I tried either one, and I'd really REALLY wish I was in a BRS-equipped airplane in that case.
 
MarkL said:
Just facilitating open discussion and sharing tools for your IFR toolbox, your choice if you want to use them.:rolleyes:
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Mark,

Please forgive me. I'm just being a smart-xxx today. :redface:
 
TMetzinger said:
Hope I never have to choose between the two options - part of me thinks the energy in a spin might be less than in the spiral dive that might develop from trying to keep wings level using just the compass. I'd make my peace with God before I tried either one, and I'd really REALLY wish I was in a BRS-equipped airplane in that case.
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Is the BRS an option in a spin?
 
No, this situation (total gyro failure, above the clouds, no VFR in range) would be one place where I'd pull the BRS chute if I had one.

Failing that, it's a choice between spinning down through the clouds (yuck), or trying a no-gyro descent through the clouds with just a whisky compass (double yuck).

So I'd pull the chute over either of those options if I had a chute.
 
TMetzinger said:
No, this situation (total gyro failure, above the clouds, no VFR in range) would be one place where I'd pull the BRS chute if I had one.

Failing that, it's a choice between spinning down through the clouds (yuck), or trying a no-gyro descent through the clouds with just a whisky compass (double yuck).

So I'd pull the chute over either of those options if I had a chute.
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I've only been in one airplane with TC and AI on same vacuum driven gyro. That airplane has a standby vacuum pump, but I think the time bewteen recognition of vacuum failure and turning on the standby is the danger zone.

If both TC and AI are dying, it would take some serious cross check and analysis to catch it before the airplane assumes an unusual attitude.

Every other airplane I've been in has had an electric TC and a Vacuum AI (which I prefer).

One of the small dislikes I have with G1000 backup systems is no TC.

The Turn Coordinator is not exploited as much as it should be on approaches, IMHO.

If the wings are level (TC), the Power (MAP or RPM), Attitude (ASI), and Configuration (Gears, Flaps) are set to known values, the airplane is going to descend (VSI) and maintain localizer centerline. If there's a drift, bank slightly into it using rudder only, level the wings, and then maintain centerline. If the airplane doesn't bank, the airplane won't turn.

I'm probably repeating what everyone already knows but oh well... It's late...
 
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I'm always interested to hear the experiences of those who have gotten their CFI or II.

Congrats, by the way.

That being said, is it just me, or does (1) fall into the category of WGAF? That seems like trivia, not knowledge, to me. Was it an interesting tidbit that came out of a discussion, or was it a "stump the chump" kind of question?
 
TMetzinger said:
An alternative I've often heard is to spin the airplane IF you know the cloud bases are high enough to permit recovery.

Hope I never have to choose between the two options - part of me thinks the energy in a spin might be less than in the spiral dive that might develop from trying to keep wings level using just the compass. I'd make my peace with God before I tried either one, and I'd really REALLY wish I was in a BRS-equipped airplane in that case.
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Trust me, a spin (in an airplane approved for spins and one that doesn't tend to fall out of a spin into a spiral) if far more likely to lead to a survivable pullout than any spiral. The term "graveyard spiral" isn't an oxymoron, even if you manage to keep the wings on while in the clouds, recovery once you reach the VMC below the clouds is unlikely.

That said, a better choice would be to use a compass on an easterly or westerly heading (backed up with GPS if you have that) with the airplane trimmed and powered for a descent at a speed about halfway between Va and 1.3 Vs, steering only with rudder.
 
lancefisher said:
Trust me, a spin (in an airplane approved for spins and one that doesn't tend to fall out of a spin into a spiral) if far more likely to lead to a survivable pullout than any spiral. The term "graveyard spiral" isn't an oxymoron, even if you manage to keep the wings on while in the clouds, recovery once you reach the VMC below the clouds is unlikely.
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My dad has told me a story of getting stuck on top in a Stearman with pretty much no instrument that worked (i don't think there was even a compass). The spin was the selected method..and apperantly it is a pretty terrifying experience spinning in the clouds waiting for the ground to appear hoping there will be enough room to recover.
 
jesse said:
My dad has told me a story of getting stuck on top in a Stearman with pretty much no instrument that worked (i don't think there was even a compass). The spin was the selected method..and apperantly it is a pretty terrifying experience spinning in the clouds waiting for the ground to appear hoping there will be enough room to recover.
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Wow...that would not be very much fun. :no::no:
 
Thanks for the info, Mark, I certainly learned something.

The other day in my instrument training we were dealing with dead reckoning. So, my electrical system went dead. Fortunately, right before that, my instructor pointed out to me that the GPS said we were 15 minutes away (this emphasized the importance of knowing where you are and where you're going on an instrument flight). Set the timer for 15 minutes, take the hood off, and I'm literally directly overtop the airport. Wow, that dead reckoning thing worked pretty well.

But in reality, it emphasized the importance to me of the battery-powered GPS. One pilot I know said a while back "That's the only thing that will save you if your nav instruments go out." I disagree with him, and my lesson showed that you still have other options, but I do agree it would be really helpful to have in the even of the electrical failure.

Mark, the engineer in me has a question here:

MarkL said:
5) The descent rate to maintain the standard 3 degree glideslope can be approximated with the following: ( Ground Speed / 2 ) X 10
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Units? I'm guessing kts or maybe mph, but it could also theoretically be furlongs/fortnight... :D
 
MarkL said:
1) Marker beacons transmit on a freq of 75 megahertz.
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And that's important because...?
3) If you lose all instruments and need to descend through a cloud layer, use the magnetic compass on a southerly heading. On the southerly heading, it will be real sensitive to direction change and you should be able to maintain that southerly heading as you descend.
Click to expand...
Better to pull out your handheld GPS.
6) The VSI is the best instrument to monitor when holding a GS descent as it will tell you the trend immediately, that is... if your descent rate changes, it will show this deviation before your GS needle does.
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Unless you've got an IVSI, that's contrary to my experience.
 
Ron Levy said:
And that's important because...?
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I'm glad you asked that question! I scrolled down to see if anyone had asked. WHY does it matter for a CFII to know that marker beacons broadcast on 75MHz? That doesn't belong on a CFII oral, it belongs on an avionics tech written exam.

I don't "tune" the thing, so why would I care what frequency it operates on??? Useless clutter in my brain.
 
dmccormack said:
One of the small dislikes I have with G1000 backup systems is no TC.
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In the Cessna G1000's with the KFC155 autopilot, there is a TC to drive the King autopilot, it's just mounted BEHIND the panel where you can't see it. Why they didn't just put it on the right side of the panel where it was visible (and usable!) makes no sense to me, unless they just didn't want to "un-pretty-fy" the glass cockpit.
 
FlyNE said:
Wow...that would not be very much fun. :no::no:
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This is why the guys flying the mail in all sorts of weather in old DH4s and Jennies back in the day wore parachutes and went over the side if they got caught in clouds or stuck on top... :D
 
dmccormack said:
One of the small dislikes I have with G1000 backup systems is no TC.
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Given the choice of having an AI but no TC, or a TC but no AI, I don't think there's any question of which way I'd jump, so I'd be OK with the backup the way it is.
 
TangoWhiskey said:
I'm glad you asked that question! I scrolled down to see if anyone had asked. WHY does it matter for a CFII to know that marker beacons broadcast on 75MHz? That doesn't belong on a CFII oral, it belongs on an avionics tech written exam.

I don't "tune" the thing, so why would I care what frequency it operates on??? Useless clutter in my brain.
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That's why I thought it belonged in the category of Who Gives A F**k?!!
 
Probably because the TC in the G1000s that have them is powered by the same buss as the G1000 itself. I bet there was some thinking that the most likely failure mode that would render your G1000 AHARS unusable would also spin down the TC.

Does anyone know of public data on the AHARS failure rate? I'm specifically talking about a failure of the G1000's ability to display attitude, not a display failure, or a complete electrical failure. I've got several hundred hours behind various G1000s now and the only failure I've ever encountered was a situation where the alerter chime wouldn't silence (even when there were no alerts displayed). I've never lost attitude or air data or nav, except in the sim.
 
TMetzinger said:
Probably because the TC in the G1000s that have them is powered by the same buss as the G1000 itself. I bet there was some thinking that the most likely failure mode that would render your G1000 AHARS unusable would also spin down the TC.

Does anyone know of public data on the AHARS failure rate? I'm specifically talking about a failure of the G1000's ability to display attitude, not a display failure, or a complete electrical failure. I've got several hundred hours behind various G1000s now and the only failure I've ever encountered was a situation where the alerter chime wouldn't silence (even when there were no alerts displayed). I've never lost attitude or air data or nav, except in the sim.
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Ahh.. that makes sense.

The C182 in the CAP Wing I'm a member of is an early G1000 model and I have heard (all second hand) stories of frequent failures, but I cannot confirm or deny. That A/c is an hour's drive and the 172 is 30 min drive and the C172N/180HP sips 7 gal/hour...

The stories of failures may just be grumbling Luddites hoping to return to the L-19....
 
dmccormack said:
If the wings are level (TC), the Power (MAP or RPM), Attitude (ASI), and Configuration (Gears, Flaps) are set to known values, the airplane is going to descend (VSI) and maintain localizer centerline. If there's a drift, bank slightly into it using rudder only, level the wings, and then maintain centerline. If the airplane doesn't bank, the airplane won't turn.

I'm probably repeating what everyone already knows but oh well... It's late...
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MarkL, thanks for this discussion. I just had my second instrument lesson yesterday, so please bear with me if my questions are evident to most of you.

Dan, I asked my CFII yesterday while under the hood whether I should use rudder only to make slight corrections to bank (i.e. 5-10 degrees off heading) with rudder only, as I was taught during my PPL training. He said no - that I should use ailerons and rudder for coordination, with the reason being that you would be skidding back to the heading, and that I should remain coordinated at all times. Is that a different situation from your advice above re: using the rudder, wings level?
 
nddons said:
MarkL, thanks for this discussion. I just had my second instrument lesson yesterday, so please bear with me if my questions are evident to most of you.

Dan, I asked my CFII yesterday while under the hood whether I should use rudder only to make slight corrections to bank (i.e. 5-10 degrees off heading) with rudder only, as I was taught during my PPL training. He said no - that I should use ailerons and rudder for coordination, with the reason being that you would be skidding back to the heading, and that I should remain coordinated at all times. Is that a different situation from your advice above re: using the rudder, wings level?
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In my opinion it is VERY hard to bank 2 or 3 degrees. Inside the FAF you shouldn't be correcting more than 5 degrees on any one correction, anyway.

Rudder allows very small adjustments in heading, without requiring the roll in and roll out in a normal banked turn, which tends to introduce more instability than it is worth.

However -- rudder only heading correction is a technique -- I certainly am not criticizing or correcting your instructor, so please don't take it as such.
 
dmccormack said:
Rudder allows very small adjustments in heading, without requiring the roll in and roll out in a normal banked turn, which tends to introduce more instability than it is worth.

However -- rudder only heading correction is a technique -- I certainly am not criticizing or correcting your instructor, so please don't take it as such.
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Please don't ever use that technique in a jet
 
dmccormack said:
In my opinion it is VERY hard to bank 2 or 3 degrees. Inside the FAF you shouldn't be correcting more than 5 degrees on any one correction, anyway.

Rudder allows very small adjustments in heading, without requiring the roll in and roll out in a normal banked turn, which tends to introduce more instability than it is worth.

However -- rudder only heading correction is a technique -- I certainly am not criticizing or correcting your instructor, so please don't take it as such.
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I would agree and was taught the rudder technique for use in flying a GA airplane, but as Correction mentioned, that's a great way to fill some sick sacks in a larger plane :yes:. In something with a large arm from the CG to the rudder and aft pax seats, they're going to get quite a ride. And if you're in a plane with a yaw damp and rudder that's not hydraulically actuated it's not going to work without shutting off the yaw damp. Sometimes bank is the only way to make corrections, but as you mentioned, very small corrections is all it should take (and all you'd want to do) on the approach.
 
I would think that a jet is more stable on the localizer than a 3600 GW SEL airplane.

The Bonanza series has a rudder-aileron interconnect -- while it's a bit off putting at first (especially during crosswind landings) -- once you get the hang of it it's a feature.

1-2 even 3 degrees of heading correction is much easier with light pressure on the rudder, and then coordinated recovery if the wings don't remain level.

I've suggested this technique to a IR student who was flying S turns across the localizer and it reduced the activity appreciably.
 
I was asked the same question about the compass heading on my instrument checkride. Was your DE a guy named Dudley Tarlton?

BTW: I don't think its possible to use a GPS as a primary heading indicator especially if you are trying to use it to keep the wings level: it lags too much.
 
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