Shooting ILS with accuracy

2nd505th

2nd505th

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2nd505th
I just hit the 40 hr mark on my instrument, 6.2 in actual and I feel comfortable in actual. I enjoy flying instrument, I suppose because I like the companionship of the ATC along with me so I really want this ticket. Nonetheless, I'm never going to get my ticket because my ILS to 200AGL approaches are not good. Today at RYY it was all perfect on GS and LOC (Min's on ILS Rwy 27 are 1211) until about 1400' Then the GS seemed to drop line a rock and the LOC went more than 3/4 left. So once again I blew it. I keep trying different things like increasing/decreasing power, using rudder only to correct the LOC needle deflection. My instructor says power back to around 1800, lock the rate of descent with trim and use rudder if within 2 degrees of LOC center. I was pretty much there with that and next time I looked that needle was traveling left like a bullet. And yes we were to the right when the hood came off. I don't know if it is because I'm too old and slow (I'm 60) or what but I really want this thing and I know most people are ready to go at 40hrs yet I feel I need a lot of work yet.

So my ask is that I know some of you are probably bulls-eye perfect. Please share any methods or secrets you have. This is in a little 152.
 
Try this next time. After the FAF, ignore the LOC and GS needles (or cover them up) and maintain a constant heading. 80 knots and a 400 fpm descent. At 200 ft AGL, uncover the LOC/GS indicators and see how close you are. I doubt you will be that far off.
 
I always found comparing the track (NOT HEADING) against the localizer desired course to be a good way to fine-tune it.. as you get closer to the ground winds shift. Knowing that the runway course is 281, if you are slightly to the left then coming right to 282 or just 283 for a short time might help

I see a lot of people bug the heading on an old school DG and then get all topsy-turvy trying to follow that..

Instead I focus on the track on the 430 against localizer needle and the VS against glide
 
2nd505th said:
I just hit the 40 hr mark on my instrument, 6.2 in actual and I feel comfortable in actual. I enjoy flying instrument, I suppose because I like the companionship of the ATC along with me so I really want this ticket. Nonetheless, I'm never going to get my ticket because my ILS to 200AGL approaches are not good. Today at RYY it was all perfect on GS and LOC (Min's on ILS Rwy 27 are 1211) until about 1400' Then the GS seemed to drop line a rock and the LOC went more than 3/4 left. So once again I blew it. I keep trying different things like increasing/decreasing power, using rudder only to correct the LOC needle deflection. My instructor says power back to around 1800, lock the rate of descent with trim and use rudder if within 2 degrees of LOC center. I was pretty much there with that and next time I looked that needle was traveling left like a bullet. And yes we were to the right when the hood came off. I don't know if it is because I'm too old and slow (I'm 60) or what but I really want this thing and I know most people are ready to go at 40hrs yet I feel I need a lot of work yet.

So my ask is that I know some of you are probably bulls-eye perfect. Please share any methods or secrets you have. This is in a little 152.
Click to expand...
Funny, I'm almost the opposite of @sarangan on this. I must get more wind :)

I'm hardly bullseye perfect and it's impossible to tell exactly what is going on without being there, but this is the most common thing I see.

We all have a bit of a tendency to unconsciously pressure the yoke in certain ways. As we get closer to the runway a lot of us unconsciously pull up. And/or we pressure the yoke one way or the other. (I laugh at myself all the time for my non-aerodynamic left turning tendency). Part of the cure is a lighter touch to let the trimmed stability do the heavy work. ut the biger part of the cure is what I put in red and the scan.

Especially early on, we tend to have a "scan for all seasons." We use the same scan whatever the situation. I see it with friends - very good instrument pilots - they will be left of localizer, heading left, and I'm sitting there wondering when they are going to correct. What they didn't do was prioritize their scan. And on an approach, whether ILS or GPS, the narrowing of the deviation means you have to give the attitude indicator (@sarangan is right about that) and those needles more priority. Of course, you need to confirm power and VSI are where you want them to be, but assuming that's been set, you primary altitude reference is that glideslope/glidepath needle and you primary course reference is that left/right deviation needle. Those guys who have it locked? The are catching he smallest deviation so early and are correcting it with an immediate correction so small, it's almost unnoticeable. That does not mean fixating on it, but it does mean giving it more attention on approach than en route.
 
I am at 40 hrs, and my partial panel VOR missed approaches are going to be my downfall. It’s my transition to full power and reconfiguration that has me fluctuating all over. Easy to say screw-it, but after all this work...I am taking a few days off now, then back at it full go.

For me on the LOC, I had to focus on my heading and NOT the LOC needle. Made small corrections to heading, and watch if LOC needle is moving favorably.

My CFI had me do half rate turns of 1-3 seconds on my ILS approaches to experiment. It worked for me. Felt unnatural to bang a half rate turn for a second and then immediately bang straight and level, but it worked (rather than being gentle with it). CFI +3k hrs by the way.

Heading is key. Less than a few degrees is all it takes. Don’t fly the LOC needle, fly the heading.
 
^Precision is critical here. you see lots of people over control. You have to make tiny corrections to heading and vertical speed and then wait and see how the needle reacts
 
2nd505th said:
using rudder only to correct the LOC needle deflection.
Click to expand...

You don't use control inputs to correct needle deflections. You use them to maintain heading and descent rate and adjust those to correct needle deflections.

That said, I don't like the rudder-only technique, except to counteract tailwagging in turbulence. Perform small coordinated turns with less than 5 degrees bank to adjust heading in 2 degree increments.
 
For the G/S, do you know the pitch attitude which will keep you on the G/S in your normal approach configuration? If not, figure it out.

Once you know that pitch attitude, that is your base attitude. If you put the nose at that attitude you will stop the G/S needle from moving. Adjust up, or down, from that attitude. When the G/S is centered, go right back to it.
 
2nd505th said:
I just hit the 40 hr mark on my instrument, 6.2 in actual and I feel comfortable in actual. I enjoy flying instrument, I suppose because I like the companionship of the ATC along with me so I really want this ticket. Nonetheless, I'm never going to get my ticket because my ILS to 200AGL approaches are not good. Today at RYY it was all perfect on GS and LOC (Min's on ILS Rwy 27 are 1211) until about 1400' Then the GS seemed to drop line a rock and the LOC went more than 3/4 left. So once again I blew it. I keep trying different things like increasing/decreasing power, using rudder only to correct the LOC needle deflection. My instructor says power back to around 1800, lock the rate of descent with trim and use rudder if within 2 degrees of LOC center. I was pretty much there with that and next time I looked that needle was traveling left like a bullet. And yes we were to the right when the hood came off. I don't know if it is because I'm too old and slow (I'm 60) or what but I really want this thing and I know most people are ready to go at 40hrs yet I feel I need a lot of work yet.

So my ask is that I know some of you are probably bulls-eye perfect. Please share any methods or secrets you have. This is in a little 152.
Click to expand...

This theory works well for me. Once established inbound I do not look at the heading indicator very much.

 
The single most important lesson i took while training IFR was the following: Set up straight/level/trimmed VFR Hands off the yoke and practice clinbs/decents/turns to PTS. Then track vor/loc/gs/approaches. THEN put the foggles on and do the same process. Then partial panel (no vac) and do it all again. I did this over 3 lessons and then would revisit a few more times, typically going straight to partial panel. In fact the second half of training was pretty much all PP. Massive improvement in precision, relaxation, concentration, focus. BTW, if you can do this in a 152, you're good to go on pretty much any other FG SEL.

Sent from my SM-G960U1 using Tapatalk
 
60 is not too old to be competent at instrument flight. I'm 65 and still flying instruments and in IMC, and hope to do so for many more years. So, let's get down to basics:
  • How are you configuring for approach and descent? Are you flying your plane "by the numbers," that is, do you know your pitch and power (rpm) settings that will yield level flight and a 500 fpm descent for your chosen approach speed? (In my AA-5, approaches are normally flown at 90 kt, which is 2100 rpm and 2 degrees nose nigh for level flight, and 1900 rpm and and 1 degree nose low for a 500 fpm descent) If you are chasing pitch and power settings on approach, you are doubling your workload. If you have a stiff headwind, you might need a touch more power, or if there is a strong tailwind, a touch less power. But know your no-wind starting point and adjust from there. In my plane, if the VSI is showing 500 fpm when I start the descent on the GS, I know I'm pretty close to the proper setting to stay on the GS.
  • Early in the approach find your "reference" settings for heading and pitch/power that keep the CDI steady. This is when you might fine-tune your initial power setting to maintain the proper rate of descent with the existing headwind/tailwind component. If the CDI is steady during the initial part of the final approach, you are are not drifting right or left, and are on the right rate of descent. While the reference setting will change slightly during the approach, this is your "safe harbor" to stop CDI movement. Once you find/know your reference settings, you can apply additional inputs to corral CDI deviations.
  • How are you controlling pitch excursions? If you are changing power constantly to control descent, see the first bullet. That is too coarse a control for small, TEMPORARY changes in vertical deviation. For TEMPORARY excursions from the glide slope due to turbulence or inattention, gently use a small input to the elevator to ARREST them immediately. You will likely soon have to return to the reference setting. If you have to hold elevator pressure for more than a little bit, re-trim to relieve pressure and this is your new reference setting. Only if slight elevator changes are not sufficient to keep the glideslope under control, THEN change power settings. Normally, major power changes won't be required if you have the right pitch/power numbers dialed in, unless there is a bodacious change in headwind/tailwind with altitude. You are not "chasing" the CDI to fix the deviation in one go. You make an input, HOLD it, and see what it does. If it ARRESTS the change, good. This is your new reference setting, at least for now. If the CDI doesn't come back on its own after it is arrested for a bit, add a LITTLE more input, and HOLD it, and see if it starts correcting. Once back to center, return to the reference setting. If you don't re-trim while making the correction input, it is as simple as returning to the "reference" trim setting.
  • How are your controlling course deviation excursions? SLIGHT heading changes are the order of the day, maybe only 2-3 degrees. You can do this with gentle pressure on the rudder, or brief coordinated turns. (I prefer short turns.) Again, you are not "chasing" the CDI. If you have a deviation, make a small course change input and HOLD it. If the input arrests the deviation, this is your new reference heading. ADD a little more heading change and HOLD it. When the CDI centers, go back to the reference heading to STOP it there.
  • The key is to ARREST deviations immediately, verify deviations are arrested, and note the current reference heading and power/pitch settings, then apply ADDITIONAL small inputs to return the CDI to center in both axes. When you get the CDI back to center, you go back to your reference heading and pitch/power settings. If the CDI is steady, you have the right heading and pitch/power setting, even if you are off center.
  • Keep your AI, DG/HSI and rpm setting near the "numbers" and things won't get out of kilter very quickly. Deviations occur not just when there is turbulence on the final approach course, but when you let the pitch/power/heading values get away from the reference numbers. Like when you are asked to divert your scan and attention to switch to tower at the FAF.
If you know your "numbers", determine your "reference" settings for heading/pitch/power early in the approach, and concentrate on ARRESTING, then patiently CORRECTING deviations by applying small corrections by HOLDING and EVALUATING them and RETURNING to your reference settings when the CDI is centered, it is possible to keep the needles in the doughnut on an ILS or GPS approach. (My G5s don't have doughnuts, so plus or minus a dot will do.) This is a lot simpler to do than it is to describe.

Hope this helps.
 
Get an efis with needles and a runway pictured in front of you on it. Or better yet, just fly lpv's.
 
midlifeflyer said:
We all have a bit of a tendency to unconsciously pressure the yoke in certain ways. As we get closer to the runway a lot of us unconsciously pull up. And/or we pressure the yoke one way or the other. (I laugh at myself all the time for my non-aerodynamic left turning tendency). Part of the cure is a lighter touch to let the trimmed stability do the heavy work. ut the biger part of the cure is what I put in red and the scan.
Click to expand...

Many of us fly with the left hand on the yoke and the right is on the throttle. I found that just the weight of my left hand on the yoke was enough to cause a left turning tendency. Had to make sure I was holding it as lightly as possible. Nice if you have an armrest for your arm. Check if you're using the yoke to support the weight of your arm.
 
Have your instructor demonstrate an approach or two. Watch how he corrects for this.
The other thing that may happen is the instructor may come up with a better way of describing what he is doing to make it work, or find out he can’t make it work the way he is describing it to you.

Brian
CFIIG/ASEL
 
Sometimes clarifying something in your own words can help you understand what you are or aren’t doing, so can you explain how to
2nd505th said:
lock the rate of descent with trim
Click to expand...
And how your other inputs may affect that?
 
You can't explain how trim controls rate of descent, because it doesn't...trim is better used to neutralize control pressure. If you use trim to control descent rate you are going to be busy as a one-armed paper-hanger during approach. And your approach speed will be all over the map.

PITCH and POWER (attitude and rpm) control descent rate. You can make a WAG about what pitch/power combo will work, or you can figure out the numbers in advance. If you know the "numbers" you can nail descent rate pretty close every time. If you fine tune the power/pitch for level flight at your desired approach speed prior to the IAF you are pretty much set up to initiate the proper descent rate when necessary by simply reducing rpm by the usual increment.

Flying by the "numbers" was the early revelation for me during IFR training, courtesy of a good instructor. Our full first day of IFR instruction was learning and applying pitch/power combos for all the common flight regimes: level cruise, level flight at approach speed, 500 fpm at approach speed, Vy climb, etc. I still have those numbers written down (and embossed on my brain) today for the plane I fly. Apply the right pitch/power combo for the flight regime desired, and Bob's your uncle. After that only small changes in power are needed to fine tune the descent rate to account for the headwind component. With experience, you can even anticipate that small adjustment based on ATIS or AWOS.
 
chemgeek said:
You can't explain how trim controls rate of descent, because it doesn't...trim is better used to neutralize control pressure. If you use trim to control descent rate you are going to be busy as a one-armed paper-hanger during approach. And your approach speed will be all over the map.

PITCH and POWER (attitude and rpm) control descent rate. You can make a WAG about what pitch/power combo will work, or you can figure out the numbers in advance. If you know the "numbers" you can nail descent rate pretty close every time. If you fine tune the power/pitch for level flight at your desired approach speed prior to the IAF you are pretty much set up to initiate the proper descent rate when necessary by simply reducing rpm by the usual increment.

Flying by the "numbers" was the early revelation for me during IFR training, courtesy of a good instructor. Our full first day of IFR instruction was learning and applying pitch/power combos for all the common flight regimes: level cruise, level flight at approach speed, 500 fpm at approach speed, Vy climb, etc. I still have those numbers written down (and embossed on my brain) today for the plane I fly. Apply the right pitch/power combo for the flight regime desired, and Bob's your uncle. After that only small changes in power are needed to fine tune the descent rate to account for the headwind component. With experience, you can even anticipate that small adjustment based on ATIS or AWOS.
Click to expand...
No, trim doesn't control rate of descent. But I can trim so the plane flies at a given airspeed. If I trim for level flight, adding power makes the plane climb at that airspeed while reducing power causes a descent at that airspeed.
The statement:
"If you fine tune the power/pitch for level flight at your desired approach speed prior to the IAF you are pretty much set up to initiate the proper descent rate when necessary by simply reducing rpm by the usual increment."
could be rewritten as:
"If you trim for level flight at your desired approach speed prior to the IAF you are pretty much set up to initiate the proper descent rate when necessary by simply reducing rpm by the usual increment."
What you have done is pitch for level flight at the desired speed (as you say we should), then use the trim to relieve the control pressure (again, as you mention).
You aren't wrong, I read it as downplaying the use of trim, or maybe I'm just seeing it from a slightly different perspective.
 
2nd505th said:
I just hit the 40 hr mark on my instrument, 6.2 in actual and I feel comfortable in actual. I enjoy flying instrument, I suppose because I like the companionship of the ATC along with me so I really want this ticket. Nonetheless, I'm never going to get my ticket because my ILS to 200AGL approaches are not good. Today at RYY it was all perfect on GS and LOC (Min's on ILS Rwy 27 are 1211) until about 1400' Then the GS seemed to drop line a rock and the LOC went more than 3/4 left.
Click to expand...
My instructor used to say, "if you haven't got pitch you haven't got sh_t". Even in the most truck like of airplanes (P3, and my current Seneca II) you have to scan for pitch and maintain pitch. Trim alone, is inadequate.
So once again I blew it. I keep trying different things like increasing/decreasing power, using rudder only to correct the LOC needle deflection. My instructor says power back to around 1800, lock the rate of descent with trim and use rudder if within 2 degrees of LOC center. I was pretty much there with that and next time I looked that needle was traveling left like a bullet. And yes we were to the right when the hood came off. I don't know if it is because I'm too old and slow (I'm 60) or what but I really want this thing and I know most people are ready to go at 40hrs yet I feel I need a lot of work yet.

So my ask is that I know some of you are probably bulls-eye perfect. Please share any methods or secrets you have. This is in a little 152.
Click to expand...
You have to bracket both pitch, and heading.
 
Sounds like you are trying to fly the approach too fast. In a 152 that’s hard to imagine but doable.
Knowing what power combo you need to accomplish a certain decent rate is key to simplifying the glideslope. Have a headwind will need slower descent rate=more power
Have a tail or cross faster descent rate less power.
For LOC needle fly headings to correct not chasing needle. If you have a heading bug set to what heading your anticipate the correction needed. If you to correct fly the edges of the bug... if you need to correct more gotta move the bug. When you see the LOc needle coming in follow the lubber line in meaning as the loc needle comes back on course you need to make incrementally bless and less Correction. Often ppl see the needle coming in and return to flying the heading for the runway just to get blown off further or never really get established.
 
I agree, don't control pitch with trim. If you try to do that you're letting the pitch attitude drift up and down seeking in-trim.

I actually trim just slightly nose-up, when on the G/S, so that I'm holding a slight amount of forward pressure. This makes it easier to make small pitch adjustments without overcontrolling as you can do if you're going back and forth between forward and aft pressure.
 
Just a couple of thoughts to add to all the good suggestions above:
I usually prefer instrument students to stick with one aircraft, or at least same model, throughout training, for continuity's sake, etc. But, in this case, a lesson or two in a slightly heavier aircraft might help, like a 172, slower to react to control inputs, and less twitchy than your 152, if you have access to one. I dunno, just an idea.
Another somewhat off-subject thought: any chance you practice yoga? Tree pose (stand on one leg, arms together overhead) requires the same sort of minute balance-corrections similar to flying an ILS, where overcorrecting doesn't work.
 
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Another thought. Have you flown an ILS (or LPV) without the hood? That's one of the two best methods I know to fix errors. You already do the same type of catching diversion early and correcting with slight adjustment on visual final as you need to do with the needles. Seeing the two together can bring home how little you really need to do if you stay on top of it.

(The other best method is watching someone else making the same mistakes - fortunately that's easy.)
 
sarangan said:
Try this next time. After the FAF, ignore the LOC and GS needles (or cover them up) and maintain a constant heading. 80 knots and a 400 fpm descent. At 200 ft AGL, uncover the LOC/GS indicators and see how close you are. I doubt you will be that far off.
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I presume you advocate this method only during a practice approach under VFR, and only as a one-time demonstration.
 
I think everyone starts out having these same issues. For me it was really an issue with my scan and my reaction to what I was seeing. If you start to get movement on the GS make a small correction but don't stop your scan and stare at the GS needle, keep up the scan. Once I got my scan down and I started reacting quickly to small movements with very small corrections it all came together. Once you are established and on LOC/GS watch for small movements and make very small corrections. Don't wait till you have a a 1/4 scale deflection before you make a small correction. Its like shooting a rifle, aim small and you will miss small.
 
For GS, I know that a 3* glide slope at 90kts Ground Speed is going to be 450fpm descent. So I'll fly 90kt IAS, dial in my 450fpm on the VSI adjust from there cross checking my VSI against my Glide Slope. Once you have that rate dialed in, it's easier to make small adjustments using your six pack rather than fixating on the needle. The needle is just there to let you know that you're configured properly.
 
labbadabba said:
For GS, I know that a 3* glide slope at 90kts Ground Speed is going to be 450fpm descent. So I'll fly 90kt IAS, dial in my 450fpm on the VSI adjust from there cross checking my VSI against my Glide Slope. Once you have that rate dialed in, it's easier to make small adjustments using your six pack rather than fixating on the needle. The needle is just there to let you know that you're configured properly.
Click to expand...

It's actually 477 fpm for a 3 degree descent at 90 kt IAS no-wind, but a headwind component will require less than that descent rate to stay on the GS. I usually start at the 500 fpm numbers and work down from that by adding a shade more power as necessary to find the exact pitch/power setting for the headwind component. But as you point out once you find the reference setting you can work corrections around that.
 
FORANE said:
Get an efis with needles and a runway pictured in front of you on it. Or better yet, just fly lpv's.
Click to expand...

Or best of all, get an EFIS the runway pictured and center the needles then fly the FPM (Flight Path Marker) by putting it on the touchdown point.

Synthetic vision combined with an FPM and is hard to resist.


Sent from my iPad using Tapatalk Pro
 
I'm in a similar position regarding training time as the OP. I find the setting my plane up with the exact same power and FPM on the VIS allows me to focus on following the glide slope and follow my ground track. I use the track on foreflight or the 430. I have found that solely using the CDI I seem to make much bigger corrections. When I have the ground track my corrections seem to be smaller. funny my ILS approaches are way better when the CFII has failed my vacuum system.
 
In our 141 operation which has a couple of hundred students the most common problem is glide slope tracking. The concentration on the glide slope distracts from flying the course.

I teach everyone this...glide slope tracking is simple precision descents. The skill set you need is one of the things few pilots practice.

The next time you are in the practice area work on precision descents. Practice descending at a precise airspeed and rate of descent and power setting. Remember the glide slope is nothing more than a precise rate at a precise airspeed and power setting. Determine what airspeed you will fly the final. Then determine the power setting to give you the proper glide path angle (usually 3 degrees). Then practice going from level cruise flight to those settings.

Then when you reach the glide slope intercept point simple establish those settings. The airplane will almost fly itself down the glide slope. You won’t need to chase the glide slope needle because you’ve set the airplane up to fly that glide path. All you will need is minor changes. That will free up your attention To pay more attention to course following.

precision descents is the secret.
Tex
 
What @Dave S. said also applies to localizers (or any lateral track). Fly a heading, if you need to correct turn to a different (but specific) heading. When the needle comes back to center, turn to a heading that’s more likely to work. Don’t chase needles back and forth or up and down.

These are basic skills that need to be mastered before practicing approach after approach. But as I pointed out in another thread, basic instrument flying and instrument interpretation is glossed over in favor of the glamour of flying approaches.
 
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