What type of instrument scan do you use?

What type of instrument scan do you use?

  • Control/Performance Method

    Votes: 5 12.2%
  • Primary/Supporting Method

    Votes: 6 14.6%
  • Inverted V

    Votes: 3 7.3%
  • I use whatever works

    Votes: 19 46.3%
  • I use the Force

    Votes: 3 7.3%
  • Selected Radial

    Votes: 5 12.2%

  • Total voters
    41
I advocate the "selected radial" scan, which you do not list in your choices. It uses the attitude indicator as the hub, with the eyes moving between it and the other instruments as dictated by what you are doing. For instance, for straight-and-level it is AI-altimeter-AI-heading-AI-altimeter...with a fixed power setting, why look at the airspeed? With a constant altitude, why look at the VSI? With a constant heading, why look at the turn coordinator? Some scan methods spent valuable time looking at instruments that do not provide useful information.

For more details, read THE COMPLETE ADVANCED PILOT.


Bob Gardner
 
Ditto to Bob's method. It was taught to me as the "hub and spoke" method centered on the AI.

But, I have found the Force does come in handy. :)
 
I advocate the "selected radial" scan, which you do not list in your choices. It uses the attitude indicator as the hub, with the eyes moving between it and the other instruments as dictated by what you are doing. For instance, for straight-and-level it is AI-altimeter-AI-heading-AI-altimeter...with a fixed power setting, why look at the airspeed? With a constant altitude, why look at the VSI? With a constant heading, why look at the turn coordinator? Some scan methods spent valuable time looking at instruments that do not provide useful information.

For more details, read THE COMPLETE ADVANCED PILOT.


Bob Gardner

Hmm. I can think of one reason to look at the airspeed while straight and level at a fixed power setting - ICE. Granted, I wouldn't hit it with every single flick of the eyes but I would hit it.

Bob's method probably comes closest to my own - I hit the AI every single cycle, and then hit the other relevant instruments depending on what the task is. But by every fifth cycle I've covered all the instruments and the engine gauges too. I'd probably need an eye tracker to specifically define the patten I use.

With the G1000, it's almost not a scan, it's just a PFD gestalt thing. I know what a standard rate turn looks like, I know what straight and level looks like, and I know standard climb and descent attitudes. I just take it all in and glance at the engines now and then.
 
Control/Performance and Primary/Secondary aren't scans, they're methods of instrument flying, and I teach CP because it is easier to learn and more procedurally based.

As for scanning, you can find a lot of pictures with arrows going around the panel, but I don't use them. Folks develop their own scan patterns very quickly, and those patterns change depending on phase of flight and equipment in use. Thus, I simply teach my trainees to keep their eyes moving, with the AI being the center of attention from which they eyes go and to which they return -- which seems to be a lot like Bob's "selected radial" or the other name "hub and spoke."
 
I'm not sure what method I use but whatever it is....it seems to work. It's probably a cross between staring at the PFD and glancing at the MFD. Except in the Mooney.....then I really have to work. :)
 
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I advocate the "selected radial" scan, which you do not list in your choices. It uses the attitude indicator as the hub, with the eyes moving between it and the other instruments as dictated by what you are doing. For instance, for straight-and-level it is AI-altimeter-AI-heading-AI-altimeter...with a fixed power setting, why look at the airspeed? With a constant altitude, why look at the VSI? With a constant heading, why look at the turn coordinator? Some scan methods spent valuable time looking at instruments that do not provide useful information.

For more details, read THE COMPLETE ADVANCED PILOT.


Bob Gardner

Hmmmm....interesting. I don't use the AI much at all, I use it to confirm what the ALT ASI & T&B are telling me. I think out of my 40 hrs of IR training, 38.5 I did with no AI or DG. "Learn to fly it needle ball and airspeed, and you'll always survive, and when you have an HSI & AI, it's all gravy, best of all, you'll know right away when something goes out on you." It stood me in good stead one night when my gyros froze and then I got a compounding problem of heavy icing. I truly believe that had I not been trained that way, I probably wouldn't have made it because I wouldn't have been able to handle the increased work load of partial panel and a funky handling airplane, as well as having to make critical decissions about how to handle the ice. As it was, I had no problems with the aircraft, and I noticed right away when my vacuum gyros started spooling down.
 
My scan tends to be more bow tie shaped. I use the turn coordinator and altimeter and then the AI to DG to VSI, with an occasion glass at nav and engine instruments.
 
Ah, no one has seen the in-depth study performed by nasa personnel on this very topic? Here is an accurate example of what the average pilot is really seeing!

AI
grnd speed indicator ('come-ON')
Alt
CHTs
wing (mmm beautiful)
cheetos bag (stale, again)
grnd speed ind (phhh)
radio settings
coke bottle (mmm)
gnd speed
cell phone (I thought I had set time zone auto?)
Alt
itchy spot on left knee
CDI
cheetos bag (crunchcrunch, wonder if cp can hear this)
coke
cheetos bag
gnd speed (need to upgrade from this slowpoke)
clock
co-pilots gaping mouth and associated dental work
MP
fly on glareshield (is that dead or just suspended animation?)
coke (think I'm starting to get a buzz here)
VSI
chewed pen cap on floor (ew. not me.)
Ammeter
cheetos (I wonder what they make these from?)
Pilot Getaways mag cover (I wonder if there are more complaint about the gorgeous gals in this issue?)
fuel gauge (why am I bothering to look at this anyway?)
clock
gnd speed (sheesh, I give up)
scratch on windshield (@&$# line boy!)
missing screw on window trim (@&$# mechanic!)
gnd speed (whatevvver!)
chart (hmm. wonder where we are)
cht, volts
scar on left knuckle, third digit. (remember teenage carelessness with garden tool)
dme flag
frayed edge of seat (hmm, wonder what a new interior costs)
gnd speed (ahhgg!)
cloud (pretty!)
TC
ground-in raisin dropped on floor last summer (ewww!)
and so on
 
Hmmmm....interesting. I don't use the AI much at all, I use it to confirm what the ALT ASI & T&B are telling me. I think out of my 40 hrs of IR training, 38.5 I did with no AI or DG. "Learn to fly it needle ball and airspeed, and you'll always survive, and when you have an HSI & AI, it's all gravy, best of all, you'll know right away when something goes out on you." It stood me in good stead one night when my gyros froze and then I got a compounding problem of heavy icing. I truly believe that had I not been trained that way, I probably wouldn't have made it because I wouldn't have been able to handle the increased work load of partial panel and a funky handling airplane, as well as having to make critical decissions about how to handle the ice. As it was, I had no problems with the aircraft, and I noticed right away when my vacuum gyros started spooling down.


Yup. Mines much like this. I use mostly the primaries in my normal scan and the AI when transitioning. However, with the G1000 there isn't much of a scan and I use the speed formula for standard rate turns.
 
Ah, no one has seen the in-depth study performed by nasa personnel on this very topic? Here is an accurate example of what the average pilot is really seeing!

AI
grnd speed indicator ('come-ON')
Alt
CHTs
wing (mmm beautiful)
cheetos bag (stale, again)
grnd speed ind (phhh)
radio settings
coke bottle (mmm)
......

Dave that is hilarious
 
I definately fly the control/performance method, however the scan is more like the inverted V. I never realized it until reading the book from the other thread. I don't spend much time on the AI at all. Probably why partial panel has never been the least bit difficult for me(in practice anyway). Interesting responses so far. Especially Dave's NASA findings:rofl:
 
In the IAR with its inverted electric AI I tend to use the elec DG/ALT/GPS scan in level flight. Climbs and descents throw in the ASI/Tach.

I intend to swap out the electric AI before too much longer. Will lose some of the "charm" but gain standardization on the left side of the panel.
 
Mine is kind of like Dave's.

AI. Ground speed (didn't we have a headwind going the other way, too?). Alt. Torques/massive split in power levers (this plane sucks, I want 191 back). Hot chick in row 1. CDI (oh ya, I was supposed to turn). DME/ground speed (well, at least we're making money). AI. Cabin altitude (this plane sucks, I want 171 back. We're in 171? I want 60MJ back). ASI/AI. Fuel flows/ITTs (lordy I'm glad I'm not paying the bill on this thing). TCAS (failed again...this plane sucks, I want 124 back). Alt (wow, I suck "100 high and correcting"). Ground Speed (at least we're faster than the Saab). AI/Alt/VSI. Ooo, nice sunset. Hot chick in row 1. Etc, etc, etc.
 
I intend to swap out the electric AI before too much longer. Will lose some of the "charm" but gain standardization on the left side of the panel.
Awwww, that's what makes the IAR the IAR!

As far as my scan goes I am embarrassed to admit that I have no idea what I use. I suppose it depends on the situation and the airplane I am flying at the moment.
 
I voted selected radial but whatever works is just as appropriate.

Yesterday flying over Lake Erie from OH to Ontario at 7000 I learned just how quickly the plane can get away from you. Cruising in VFR conditions with probably 3 miles lateral visibility through the Haze. Just after the shoreling passed by everything forward turns to a beautiful light blue, no visible anything forward, right or left.

As I start scanning, after commenting to my wife that this is just like real IFR conditions. I realize that we have entered an unnoticed turn, already 30 degrees off of heading with a 10 degree bank.

I kick into high speed scan mode, level the wings then gently turn back to heading. The actual scan became AI-level, Heading, Altitude repeat.

When I was satisified the plane was stable again I added in the GPSMAP 196 display for track versus heading, VSI for a tighter altitude control and occasionaly the Airspeed indicator, TC and engine instruments.

Magically the two little Islands I knew we would be passing and finally the Ontario shore came into view.
 
As far as my scan goes I am embarrassed to admit that I have no idea what I use. I suppose it depends on the situation and the airplane I am flying at the moment.

Mari, you're not alone. I've been participating in research lately with MITRE's Center for Advanced Aviation Systems Development, on things related to ADS-B and runway safety. During a recent roundtable the subject of instrument scans came up. One of the things that was observed in the sim sessions (where folks wear a device that tracks eye movement) is that experienced instrument pilots (defined as having over 1000 hours total and over 200 hours of instrument time) don't appear to have a specific scan pattern that can be detected. The only thing the pilots tested had in common what that they spent the majority of the time looking at the AI, which makes sense since the airplane has a flight director. When the flight director was disabled, they still spent most of their scan time on the AI but altimeter and the HSI came more into play.

The psychologist who oversees a lot of the studies offered the opinion that after a certain while your brain learns what instruments matter for each situation and airplane, and you don't think at all about your scan until you find you're not getting the information you need (perhaps with a failure or an unfamiliar aircraft), at which point you would think about where you are looking and adjust.

So the various scanning patterns are useful to instrument students to get them to keep their eyes moving and avoid fixation, but there's no evidence that the pattern sticks with them forever.
 
Mari, you're not alone. I've been participating in research lately with MITRE's Center for Advanced Aviation Systems Development, on things related to ADS-B and runway safety. During a recent roundtable the subject of instrument scans came up. One of the things that was observed in the sim sessions (where folks wear a device that tracks eye movement) is that experienced instrument pilots (defined as having over 1000 hours total and over 200 hours of instrument time) don't appear to have a specific scan pattern that can be detected. The only thing the pilots tested had in common what that they spent the majority of the time looking at the AI, which makes sense since the airplane has a flight director. When the flight director was disabled, they still spent most of their scan time on the AI but altimeter and the HSI came more into play.

The psychologist who oversees a lot of the studies offered the opinion that after a certain while your brain learns what instruments matter for each situation and airplane, and you don't think at all about your scan until you find you're not getting the information you need (perhaps with a failure or an unfamiliar aircraft), at which point you would think about where you are looking and adjust.

So the various scanning patterns are useful to instrument students to get them to keep their eyes moving and avoid fixation, but there's no evidence that the pattern sticks with them forever.

This is perhaps the most insightful thing I've read about instrument scans.
 
I agree... Nearly all my IR training was partial panel. I thought my instructor was demonic, but it served me well. I think half my freight flying was without an AI. Shoot, one week I put a cover on the AI and didn't notice it again until the next week when someone made a comment on it! Oh yea, forgot to take that off. It still doesn't work, btw... :cheerswine:


I'm curious - how did you legally dispatch for freight without an AI? Isn't it required for instrument flight? If the answer is "We didn't legally dispatch", that's ok, I was just wondering if I'd missed something in the regs that would let you dispatch IFR with a failed AI.
 
I'm curious - how did you legally dispatch for freight without an AI? Isn't it required for instrument flight? If the answer is "We didn't legally dispatch", that's ok, I was just wondering if I'd missed something in the regs that would let you dispatch IFR with a failed AI.

Hehehehe, never flown freight or any other utility job huh? You should have seen the PA-12 I used to fly pipeline in. That plane had so much defered stuff I finally quit when the oilpressure gauge got "defered".
 
Nope, haven't yet HAD to fly for a living - I've been fortunate that I can say "no" when someone asks me to do something I think is unsafe.

Don't get me wrong - I'll be happy to fly VFR with only the required equipment working and everything else tagged "inop". I'll be happy to fly IFR with only the required equipment. I'll be happy to ferry an airplane on a ferry permit. I won't bust a reg (and put any future flying at risk) on something as obvious as a broken AI for an IFR flight. The fact that the system is broken doesn't justify me breaking it more, but that's just me.

And while I respect the skills and experience all the freight dogs have accumulated, I don't think they should be launching in broken airplanes.
 
Nope, haven't yet HAD to fly for a living - I've been fortunate that I can say "no" when someone asks me to do something I think is unsafe.

Don't get me wrong - I'll be happy to fly VFR with only the required equipment working and everything else tagged "inop". I'll be happy to fly IFR with only the required equipment. I'll be happy to ferry an airplane on a ferry permit. I won't bust a reg (and put any future flying at risk) on something as obvious as a broken AI for an IFR flight. The fact that the system is broken doesn't justify me breaking it more, but that's just me.

And while I respect the skills and experience all the freight dogs have accumulated, I don't think they should be launching in broken airplanes.

I don't think they should either, but that just isn't the way the industry works, although with the regionals taking people with lower times, they may have to step up to the plate to get people who will fly their equipment.
 
Tim - Im late to the party but I think you're group has hit the nail on the head with the analysis on the instrument scan.
 
Actually, if the vacuum pump is busted (and hence the de-ice system as well), you can't tell the AI is inop on the ground,
Well, you can certainly tell if the vacuum pump is inop on the ground, and if the vacuum pump is out, your vacuum-driven AI is pretty much useless anyway, and you'd have to be pretty much crazy to launch IFR that way, so what's the diff if a ramp checker can tell either way?
 
This is perhaps the most insightful thing I've read about instrument scans.

It is, and interestingly enough it is alot what Gene Hudson is talking about in his book. He claims that we all have a scan which works for us. We developed it by trial and error and developing a feel for where we should be looking at any one moment. He, however, was frustrated by the "keep trying you will figure it out" method of instructing instrument students and tried to develop a system to teach a scan which works and frees up valuable time and brain power to manage other instrument flying tasks. Good reading for sure.
 
Tim - Im late to the party but I think you're group has hit the nail on the head with the analysis on the instrument scan.

Thanks, but don't give me any credit - I was just one of the guinea pigs!

The CAASD group is pretty impressive. The last "innovation" I tested with them were wave-off style lights embedded into the runway to alert an arriving or departing aircraft that the runway was unsafe due to an incursion or predicted crossing traffic - these lights apparently are going to be installed at major airports this year. At the moment we're looking at an ADS-driven EFB application to show a moving map of the airport diagram with symbology to show when a runway is occupied or about to be occupied - the goal is to reduce incursions.
 
Well, you can certainly tell if the vacuum pump is inop on the ground, and if the vacuum pump is out, your vacuum-driven AI is pretty much useless anyway, and you'd have to be pretty much crazy to launch IFR that way, so what's the diff if a ramp checker can tell either way?

How do you tell? The aircraft I was in wouldn't give you an indication until you had engines running...

As to the ramp check, I was referring to Tim's comment of risking future flying...
 
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It is, and interestingly enough it is alot what Gene Hudson is talking about in his book. He claims that we all have a scan which works for us. We developed it by trial and error and developing a feel for where we should be looking at any one moment. He, however, was frustrated by the "keep trying you will figure it out" method of instructing instrument students
It is a bit frustrating. I've seen CFIIs who leave the student to his own devices and others who try to lock the student into a specific type of scan. Or, worse, CFIIs who thought that the FAA's "primary/supporting" instrument paradigm was a scan technique, not just a way of understanding and interpreting the instruments. (oops! I think I just called one or maybe two of the poll answers irrelevant)

I try (how successfully is for others to say) to try to guide a student into developing a scan that contains certain elements: (a) an understanding of what instruments give the most useful information about a particular flight conditions; (b) a way of moving among them that allows for interpretation without fixation; and (c) a way of cross-checking them to detect and resolve errors.

The biggest example I had of this was a pilot who was doing some recurrent training. The interesting part was that his partial panel flight was far better than his full panel flight. Watching him, it seemed to me that the "extra" instruments had him moving too quickly among all of them, never really seeing and reacting to the information. All I suggested to him was that, with a full panel, he was "allowed" to treat the AI as the replacement for "out the window" and use the other instruments as a cross-check against it, similar to what he would do in visual flight. His eyes immediately stopped darting around and settled into a scan that worked.
 
What I know for sure is the best way for me to improve my scan is to put me in a simulator with a sadistic SOB working the board.

I discovered that when one engine quits and the vac pump on the working engine quits (in the clouds flying the approach) my scan doesn't include the oil pressure gauge for the working engine - even when my training partner is sitting there saying, "something is not right on your airplane - can you find it?"

It took about three minutes for me to lose oil pressure on the good engine and, even though I looked at it, I never recognized it as a problem. Hahahaha. Gee, they had some fun.
 
It is a bit frustrating. I've seen CFIIs who leave the student to his own devices and others who try to lock the student into a specific type of scan. Or, worse, CFIIs who thought that the FAA's "primary/supporting" instrument paradigm was a scan technique, not just a way of understanding and interpreting the instruments. (oops! I think I just called one or maybe two of the poll answers irrelevant)

I try (how successfully is for others to say) to try to guide a student into developing a scan that contains certain elements: (a) an understanding of what instruments give the most useful information about a particular flight conditions; (b) a way of moving among them that allows for interpretation without fixation; and (c) a way of cross-checking them to detect and resolve errors.

The biggest example I had of this was a pilot who was doing some recurrent training. The interesting part was that his partial panel flight was far better than his full panel flight. Watching him, it seemed to me that the "extra" instruments had him moving too quickly among all of them, never really seeing and reacting to the information. All I suggested to him was that, with a full panel, he was "allowed" to treat the AI as the replacement for "out the window" and use the other instruments as a cross-check against it, similar to what he would do in visual flight. His eyes immediately stopped darting around and settled into a scan that worked.

I have never tried it, but that is exactly what the inverted V scan is all about. Attitude indicator, turn coordinator, VSI. If these are kept in check, IE: not turning, not climbing. Then there is no need to look at the other instruments, cause they won't be moving. I balked on the VSI thing at first because of the inherent delay. However as a trend instrument there is no delay, just as a rate instrument. The trend is what you are trying to control. The only time I can see the VSI as being useless in this regard would be in turbulence. Hell, mine bounces up and down like it's posessed.

Oh, and by the way, Ron beat you to it on the poll.;) It's what I get for throwing it together in a hurry and not thinking about what I put on it.
 
The psychologist who oversees a lot of the studies offered the opinion that after a certain while your brain learns what instruments matter for each situation and airplane, and you don't think at all about your scan until you find you're not getting the information you need (perhaps with a failure or an unfamiliar aircraft), at which point you would think about where you are looking and adjust.
I agree with this. I spent all of my life flying airplanes with steam gauges and then had to learn how to fly with EFIS where some of the instruments were combined. The airspeed indicator was a tape and integrated with the AI. The VSI and altimeter were also in one instrument. This took a little bit of adjustment and I had to think about what I was looking at. However, it soon became second nature and I had no problems switching back and forth between the two.
 
I'm working on a good scan now. I've found something odd that happened with me. Most of my inst. time is in the H-60 and I never had a problem with my scan. I used the hub and spoke method. Now I'm getting my required 15 hours in an airplane inst. transition and found that my scan that works in the H-60 sucks in the airplane. In the H-60 I focus a lot on the AI because it has a "roll command bar" much like a flight director and it displays a lot of other information on the AI. In the airplane (Piper Archer II) I tend to drift off my heading because I found I don't check the DG as much as I should (or omit it entirely). This is because of the flight director function in the AI and the flight path stabilization system that will "hold" your heading in the H-60. To put it simply...The Blackhawk spoiled me. Now I have to sharpen my scan up in the airplane...but I still will keep what I'm doing in the H-60 because I know it works for me....just not in the airplane!
 
Like Henning (and anyone who did their IFR at GATTS) I learned without an AI. The turn coordinator was a major scan stop. Although I don't cover up the AI when I'm hand flying my Mooney in IMC, that TC is very important.
However, I quickly discovered that a Lear does not have a TC:eek:. (There's some RMI thingy parked where the TC should be :rolleyes:) But I also discovered that one quickly adapts and that's why I voted for "whatever works."
One of these days I hope I get a chance to fly EFIS glass. I hope I'll be able to adapt to that too.
 
Ah, no one has seen the in-depth study performed by nasa personnel on this very topic? Here is an accurate example of what the average pilot is really seeing!

(snip)

:rofl: That list was the best thing I've read all day! Hilarious! :)
 
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