ILS Approach and Landing Speeds

Ron Levy said:
Beyond the original question, the discussion has moved into one of the most important issues in Single Pilot IFR (SPIFR) operations -- the problem of shifting attention between the flight instruments and the view forward at the bottom of an instrument approach. This is solved in some high-end aircraft with Head-Up Displays (HUD's) which allow the pilot to have the flight instrument readouts projected into the forward view so the pilot can keep "flying the gauges" until reaching the MAP while simultaneously seeing if the runway environment appears. But what is the light plane pilot to do?.
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Ron -- why don't you simply add the windscreen as part of the instrument scan?

After all, if you're tracking an ILS you can maintain heading with wings level. Descent rate should be stabilized and so a glance at the VSI should confirm the rate that will maintain glideslope. Check the needles to confirm -- glance up, return to scan.

:dunno:
 
dmccormack said:
Ron -- why don't you simply add the windscreen as part of the instrument scan?

After all, if you're tracking an ILS you can maintain heading with wings level. Descent rate should be stabilized and so a glance at the VSI should confirm the rate that will maintain glideslope. Check the needles to confirm -- glance up, return to scan.

:dunno:
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Addition to the above comment:

If you're on an ILS and you aren't getting bounced like a kid in a bounce-house, you should be fairly stable in the approach and really just slightly correct here or there for the localizer which leaves plenty of time to glance outside and try to see anything at all.

I don't know, I guess to each their own, but I definitely don't wait till mda/dh to look outside
 
dmccormack said:
Ron -- why don't you simply add the windscreen as part of the instrument scan?
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Two reasons -- head movement and eye focus. If you look up at the windscreen, you have to shift your eyes a long way from your primary instrument scan, and generally have to move your head, too, and that creates a number of issues. Also, as you look up, your eye focus zooms out, and then when you look back at the instruments your eyes have to refocus. Better to let peripheral vision let you know when you're breaking out and limit the number of times you direct your eyes away from your primary instrument scan until you reach the point where you expect to see something outside (which may be well above MDA/DH, depending on conditions).
 
Ron Levy said:
Two reasons -- head movement and eye focus. If you look up at the windscreen, you have to shift your eyes a long way from your primary instrument scan, and generally have to move your head, too, and that creates a number of issues. Also, as you look up, your eye focus zooms out, and then when you look back at the instruments your eyes have to refocus. Better to let peripheral vision let you know when you're breaking out and limit the number of times you direct your eyes away from your primary instrument scan until you reach the point where you expect to see something outside (which may be well above MDA/DH, depending on conditions).
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Sorry, I just don't think that's true -- I'm not "looking" to read a road sign -- I'm acquiring a strip of darkness in daytmioe haze, blue taxiway lights, approach lights -- things that are visible at a glance.

In the same way I usually don't look at the altimeter once straight and level -- It's on the periphery, but doesn't get looked at the same way the Atitude Indicator does.

It sounds like you're advocating some sort of sudden, discrete, change of focus/attention at DA/MDA, and I think that's more difficult than adding another cue during the normal instrument scan.
 
elmetal said:
Addition to the above comment:

If you're on an ILS and you aren't getting bounced like a kid in a bounce-house, you should be fairly stable in the approach and really just slightly correct here or there for the localizer which leaves plenty of time to glance outside and try to see anything at all.

I don't know, I guess to each their own, but I definitely don't wait till mda/dh to look outside
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Exactly right.
 
elmetal said:
Not to mention if you happen to find yourself in VMC, traffic is on you anyway. (Bravo and possibly charlie not so much but otherwise)
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Well, I'll admit to easing up the VFR scan when inbound at my friendly neighborhood Class D airport, but uncontrolled fields? As soon as I'm visual I'm visual, period.

Of course with a safety pilot on a training flight I can practice down to 200' etc. But we're talking about an approach in IMC and acquiring the runway environment at some point. As Jesse mentioned earlier, once I acquire, I change from gauges to windscreen and that's that.
 
dmccormack said:
Well, I'll admit to easing up the VFR scan when inbound at my friendly neighborhood Class D airport, but uncontrolled fields? As soon as I'm visual I'm visual, period.

Of course with a safety pilot on a training flight I can practice down to 200' etc. But we're talking about an approach in IMC and acquiring the runway environment at some point. As Jesse mentioned earlier, once I acquire, I change from gauges to windscreen and that's that.
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Amen. What I see (if I see) is more important than what the instruments tell me.

In VMC that is.
 
Ron Levy said:
Two reasons -- head movement and eye focus. If you look up at the windscreen, you have to shift your eyes a long way from your primary instrument scan, and generally have to move your head, too, and that creates a number of issues. Also, as you look up, your eye focus zooms out, and then when you look back at the instruments your eyes have to refocus. Better to let peripheral vision let you know when you're breaking out and limit the number of times you direct your eyes away from your primary instrument scan until you reach the point where you expect to see something outside (which may be well above MDA/DH, depending on conditions).
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Again, this is how my CFII learned me to fly them approach things.
 
elmetal said:
Not to mention if you happen to find yourself in VMC, traffic is on you anyway. (Bravo and possibly charlie not so much but otherwise)
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But I think that's where the part about getting the weather before the approach comes in. For example, if you expect to pop out 2,000 feet above, you pretty much know you're going to be scanning for VFR traffic, whereas if the airport is near minimums it is unlikely that you'll have people doing circuits.
 
And a question to everyone about SPIFR, but with a passenger. If, for example, you are on an ILS with your spouse, girlfriend, bff, etc. next to you, do you ask them (as you might ask a pilot not flying) to keep eyes out to look for when you break out?
 
spiderweb said:
But I think that's where the part about getting the weather before the approach comes in. For example, if you expect to pop out 2,000 feet above, you pretty much know you're going to be scanning for VFR traffic, whereas if the airport is near minimums it is unlikely that you'll have people doing circuits.
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That's pretty spot on except if it's an ATIS it can be pretty dated as far as ceiling goes but yes that's about what I do, I expect what I hear on atis/awos/asos and if I don't see if by then I'm extra attentive.
 
Ron Levy said:
Two reasons -- head movement and eye focus. If you look up at the windscreen, you have to shift your eyes a long way from your primary instrument scan, and generally have to move your head, too, and that creates a number of issues. Also, as you look up, your eye focus zooms out, and then when you look back at the instruments your eyes have to refocus. Better to let peripheral vision let you know when you're breaking out and limit the number of times you direct your eyes away from your primary instrument scan until you reach the point where you expect to see something outside (which may be well above MDA/DH, depending on conditions).
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..and this positions assumes that the instrument scan on the ILS can support no interruption (which you purport adding the windscreen introduces).

Sorry, unless you're riding a bucking bronco, ILS flying is a fairly static endeavor -- wings level, airplane descending.

You seem to argue that we cannot divide attention.

But what about the oil pressure gauge? The comm panel? Do you look at the gear indicator?

None of those are in the 6 pack scan area, and require a change in head position and eye focus.

I'm looking at the AI (or the TC if partial panel) and the VSI. The rest get cursory attention unless a change is required due to sloppiness or wind shift. As I come to the altitude I'm expecting to break out, I add the windscreen to the scan. There is a difference -- I'm not looking for the runway, instead, I'm glancing at the windshield.

The focal point isn't much different since the plexi is how far away?

There will be cues to let me know if I'm breaking out into the clear, into mist, or maybe just a hazy view. If the windshield doesn't change, I'm still IMC. If it does (and as you know, it often changes suddenly) I give it more attention, but still keep a scan going.

Once I'm certain I can continue visually, the instrument scan is minimized.
 
spiderweb said:
And a question to everyone about SPIFR, but with a passenger. If, for example, you are on an ILS with your spouse, girlfriend, bff, etc. next to you, do you ask them (as you might ask a pilot not flying) to keep eyes out to look for when you break out?
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Abso-flippin-lutely.

The amount of trust I put into the report varies, however. A fellow IR pilot I know? I'll look.

My daughter? "Thanks, honey..." while staying on the gauges.
 
dmccormack said:
Abso-flippin-lutely.

The amount of trust I put into the report varies, however. A fellow IR pilot I know? I'll look.

My daughter? "Thanks, honey..." while staying on the gauges.
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Haha, in another thread, someone said that their daughter said they saw a care bear in the clouds. Not -that- helpful, at least in this situation!
 
elmetal said:
Not to mention if you happen to find yourself in VMC, traffic is on you anyway. (Bravo and possibly charlie not so much but otherwise)
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IME there's a world of difference between dropping out of the cloud bases into vis > 3mi, vs 1/2 to 1 mile vis with the former being pretty obvious without really looking out the windshield. That said, I do peek outside well before reaching MDA or DA but I don't spend a lot of time looking out then unless my glimpse clearly shows something worth looking at more closely. And actually this is true after reaching MDA or DA.
 
gismo said:
IME there's a world of difference between dropping out of the cloud bases into vis > 3mi, vs 1/2 to 1 mile vis with the former being pretty obvious without really looking out the windshield. That said, I do peek outside well before reaching MDA or DA but I don't spend a lot of time looking out then unless my glimpse clearly shows something worth looking at more closely. And actually this is true after reaching MDA or DA.
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I agree with this. There's nothing wrong with peeking. The problem comes when someone starts searching outside because they think they see something that they try to make into a runway and in the process they get distracted.
 
Everskyward said:
I agree with this. There's nothing wrong with peeking. The problem comes when someone starts searching outside because they think they see something that they try to make into a runway and in the process they get distracted.
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Exactly -- so instead of pretending we shouldn't, we should demonstrate and practice how we should.
 
spiderweb said:
Haha, in another thread, someone said that their daughter said they saw a care bear in the clouds. Not -that- helpful, at least in this situation!
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Hey, don't laugh. Pete and I saw Cookie Monster on the way to the FlyBQ last year:

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dmccormack said:
Can you please provide ONE reference that supports your view?
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"The Human Senses in Flight," Herschel W. Leibowitz, in "Human Factors in Aviation," eds. Earl L. Weiner and David C. Nagel. In the same text, see also "Aviation Displays" by Alan F. Stokes and Christopher D. Wickens, especially on "Display Organization and Configuration: The Visual Overload Problem." Another text to check would be Ernest J. McCormack's "Human Factors Engineering," particularly the chapters on Human Sensory Processes and Visual Displays.
 
spiderweb said:
And a question to everyone about SPIFR, but with a passenger. If, for example, you are on an ILS with your spouse, girlfriend, bff, etc. next to you, do you ask them (as you might ask a pilot not flying) to keep eyes out to look for when you break out?
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You betcha -- that's basic CRM. I get them to look for and call "ground below" and "lights/ground ahead."
 
Ron Levy said:
You betcha -- that's basic CRM. I get them to look for and call "ground below" and "lights/ground ahead."
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I usually don't, simply because when I have had pax along on flights in actual and pointed the runway lights out to them ahead, they usually can't see it - They don't know what they're looking for. I'm amazed, since I don't think it's hard at all to pick out - "Look for the lines of lights that are brighter than the rest" but apparently it's pretty difficult for a non-pilot.

And, my peripheral vision is good enough that I don't need anyone to call ground contact, I'll know it before they inhale to say it.
 
Ron Levy said:
"The Human Senses in Flight," Herschel W. Leibowitz, in "Human Factors in Aviation," eds. Earl L. Weiner and David C. Nagel. In the same text, see also "Aviation Displays" by Alan F. Stokes and Christopher D. Wickens, especially on "Display Organization and Configuration: The Visual Overload Problem." Another text to check would be Ernest J. McCormack's "Human Factors Engineering," particularly the chapters on Human Sensory Processes and Visual Displays.
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I 'm familiar with Human Factors texts -- you haven't provided a reference that proves that adding the windshield to the instrument scan results in overload.
 
dmccormack said:
I 'm familiar with Human Factors texts -- you haven't provided a reference that proves that adding the windshield to the instrument scan results in overload.
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If you're lookiing for a peer-reviewed study on that specific issue, I don't know of one. But the fundamentals as described in those texts and others support what I said, and my observation of pilots during my 1400 hours of instrument training given confirms it.

And I'm done arguing with Dan.
 
Ron Levy said:
If you're lookiing for a peer-reviewed study on that specific issue, I don't know of one. But the fundamentals as described in those texts and others support what I said, and my observation of pilots during my 1400 hours of instrument training given confirms it.

And I'm done arguing with Dan.
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Otherwise known as the "appeal to authority" fallacy.

:rolleyes2:

I've been very clear on what I advocate on this in several posts here: Add the windscreen to the scan when you expect to break out.

You intend to land. The windscreen provides the best view of the stuff you're going to land on.

From the FAA's Instrument Flying Handbook:

Although no specific method of cross-checking is recommended, those instruments that give the best information for controlling the aircraft in any given maneuver should be used. The important instruments are the ones that give the most pertinent information for any particular phase of the maneuver. Although no specific method of cross-checking is recommended, those instruments that give the best information for controlling the aircraft in any given maneuver should be used. The important instruments are the ones that give the most pertinent information for any particular phase of the maneuver.
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You've provided some hand-waving about "yeah, this is hard..." without providing a proscription -- I would hope that after 1400 hours of instrument flight training you'd be able to provide a defined series of steps the Instrument Pilot can use to transition from IMC to visual flight.

Quite frankly far too many Instrument Pilots are given the "scan the instruments" command with no clear logic about which to look at and why. So we try to look at 6 instruments in level flight when we only need one -- or maybe two.
 
dmccormack said:
Quite frankly far too many Instrument Pilots are given the "scan the instruments" command with no clear logic about which to look at and why. So we try to look at 6 instruments in level flight when we only need one -- or maybe two.
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Don't people use common sense if an instructor doesn't teach them?

When I was taught about primary and secondary instruments the first thing I said to the instructor was: So what you're saying is Altimeter is one of the primaries in straight and level. Does anybody NOT use the altimeter heavily in straight and level?

His response: You'd be surprised

Oh the world we live in
 
elmetal said:
Don't people use common sense if an instructor doesn't teach them?

When I was taught about primary and secondary instruments the first thing I said to the instructor was: So what you're saying is Altimeter is one of the primaries in straight and level. Does anybody NOT use the altimeter heavily in straight and level?

His response: You'd be surprised

Oh the world we live in
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Actually, the altimeter is not part of my primary scan straight and level.

Scan would be something like this:

Attitude Indicator --> VSI
Attitude Indicator --> Turn Coordinator
Attitude Indicator --> VSI
Attitude Indicator --> Turn Coordinator
Attitude Indicator --> Engine indicator (e.g.Oil Pressure)
Attitude Indicator --> VSI
Attitude Indicator --> Turn Coordinator

Why? Several reasons:
  • If I look at the AI I can see the airspeed indicator and the altimeter in periperhal vision. Any change is noted.
  • If TC is wings level I'm not turning. If TC dips at all I cross-check DG, then correct with Attitude Indicator.
  • If VSI is 0 I'm not climbing or descending. If VSI dips at all I cross-check Altimeter, then correct with Attitude Indicator.
Read Gene Hudson's book and your instrument flying will become so much easier. Someone on here mentioned his book a while ago (thank you whoever!) -- I ordered it, read it, and agree completely -- reduce the workload by looking at the things that give you the best measure of what is happening (see FAA's incomplete discussion of "primary & supporting")
 
dmccormack said:
Actually, the altimeter is not part of my primary scan straight and level.

Scan would be something like this:

Attitude Indicator --> VSI
Attitude Indicator --> Turn Coordinator
Attitude Indicator --> VSI
Attitude Indicator --> Turn Coordinator
Attitude Indicator --> Engine indicator (e.g.Oil Pressure)
Attitude Indicator --> VSI
Attitude Indicator --> Turn Coordinator

Why? Several reasons:
  • If I look at the AI I can see the airspeed indicator and the altimeter in periperhal vision. Any change is noted.
  • If TC is wings level I'm not turning. If TC dips at all I cross-check DG, then correct with Attitude Indicator.
  • If VSI is 0 I'm not climbing or descending. If VSI dips at all I cross-check Altimeter, then correct with Attitude Indicator.
Read Gene Hudson's book and your instrument flying will become so much easier. Someone on here mentioned his book a while ago (thank you whoever!) -- I ordered it, read it, and agree completely -- reduce the workload by looking at the things that give you the best measure of what is happening (see FAA's incomplete discussion of "primary & supporting")
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I read his book and when I got to that section I was kinda like well... you know what I mean? I understand his method but I kinda prefer the other method for some configurations (such as straight and level). I'm not a big fan of using VSI to measure altitude changes because a small change in the VSI (of say 20fpm, is almost unnoticeable) but if you neglect the altimeter that 20fpm will become a big change in a few minutes. I use the VSI to make sure Im level, but after that I kinda use the alt more than the VSI

I don't use the AI as primary for straight and level I use mostly altimeter and DG with turnbank/vsi as secondary and AI every 2 scans or so. In turbulent conditions it's different but in nice smooth straight and level I find myself trying to perfect the AI and when I do alt+DG I do a heck of a lot less thinking and less correcting and more straight.

I guess it all depends on how comfortable you are with each setup. If you can accomplish all the tasks you need (like not losing or gaining altitude and not losing direction) then whatever method you use works.

By the way I agree about the book, except I think I may have heard about it on another website, but it's awesome!
 
dmccormack said:
  • If I look at the AI I can see the airspeed indicator and the altimeter in periperhal vision. Any change is noted.
  • If TC is wings level I'm not turning. If TC dips at all I cross-check DG, then correct with Attitude Indicator.
  • If VSI is 0 I'm not climbing or descending. If VSI dips at all I
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I do use the AI+periph a lot as well. I don't like using TC because it's not an extremely precise instrument, I find I can much more easily look at the DG and determine if it's moving or not.
 
I like to think of control and performance - or manufacturing and QC. Like Dan - when I'm straight and level it's the AI/TC/VSI - the TC and VSI will tell me if I'm not maintaining, and let me know what my initial correction should be. I still see the other instruments in the peripheral (well not in the G1000 - I just LOOK at that) part of the scan.
 
elmetal said:
[/LIST] I do use the AI+periph a lot as well. I don't like using TC because it's not an extremely precise instrument, I find I can much more easily look at the DG and determine if it's moving or not.
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Really? I find it is very sensitive to the slightest change in wings-level and indicates a turn before the DG does.

:dunno:
 
elmetal said:
I read his book and when I got to that section I was kinda like well... you know what I mean? I understand his method but I kinda prefer the other method for some configurations (such as straight and level). I'm not a big fan of using VSI to measure altitude changes because a small change in the VSI (of say 20fpm, is almost unnoticeable) but if you neglect the altimeter that 20fpm will become a big change in a few minutes. I use the VSI to make sure Im level, but after that I kinda use the alt more than the VSI
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I think the point is if the VSI doesn't change, the altimeter can't change.
:wink2:
 
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