Pattern Width on Downwind

Jaybird180

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Jaybird180
One persons wide pattern is another persons normal pattern. When your down low and in a pattern a 1,000 foot difference in pattern width looks like a lot.

When I was taught landings, my instructor disuaded me from trying to find a reference point on the airplane to judge distance from the runway on downwind. His reasoning was that I would fly different airplanes and that I should learn to judge by sight alone. I think his guidance may have been misguided (or misunderstood by me).

As a result, refusing to commit the 'sin' of 747 size patterns, my pattern is often too close and lately become inconsistent.

I intend to do some pattern work soon, specifically to find a sweet spot and fix the issue. Can anyone make suggestions that I can use as a starting point (ie midway on wing strut, arm width of light beyond wingtip, etc)?
 
When I was taught landings, my instructor disuaded me from trying to find a reference point on the airplane to judge distance from the runway on downwind. His reasoning was that I would fly different airplanes and that I should learn to judge by sight alone. I think his guidance may have been misguided (or misunderstood by me).
I agree with you. You should know the right reference point on each plane you fly just as you know the right V-speeds on each plane you fly. Makes it way, way easier.

I intend to do some pattern work soon, specifically to find a sweet spot and fix the issue. Can anyone make suggestions that I can use as a starting point (ie midway on wing strut, arm width of light beyond wingtip, etc)?
On your 172, putting the runway halfway up the strut is a good starting point.
 
I think your instructor was right. Are you conscious of the time you spend on the crosswind leg? Are you typically level when initiating the crosswind turn or still climbing? The pattern is simply a device for obtaining offset and traffic separation. "That's about right" is a pretty good starting point, and you can experiment with different offsets to determine the sight picture that you think is best.

The three-bears method works pretty well for this drill. For training purposes, especially in an uncrowded pattern, there's no requirement that you fly the entire downwind leg at a single offset. Try several spacings and pay attention to the big picture without fixating on the runway. I'm willing to bet that you'll find a good groove quickly.

When I was taught landings, my instructor disuaded me from trying to find a reference point on the airplane to judge distance from the runway on downwind. His reasoning was that I would fly different airplanes and that I should learn to judge by sight alone. I think his guidance may have been misguided (or misunderstood by me).

As a result, refusing to commit the 'sin' of 747 size patterns, my pattern is often too close and lately become inconsistent.

I intend to do some pattern work soon, specifically to find a sweet spot and fix the issue. Can anyone make suggestions that I can use as a starting point (ie midway on wing strut, arm width of light beyond wingtip, etc)?
 
I think your instructor was right. Are you conscious of the time you spend on the crosswind leg? Are you typically level when initiating the crosswind turn or still climbing? The pattern is simply a device for obtaining offset and traffic separation. "That's about right" is a pretty good starting point, and you can experiment with different offsets to determine the sight picture that you think is best.

The three-bears method works pretty well for this drill. For training purposes, especially in an uncrowded pattern, there's no requirement that you fly the entire downwind leg at a single offset. Try several spacings and pay attention to the big picture without fixating on the runway. I'm willing to bet that you'll find a good groove quickly.
That's all great for flying a closed pattern, but it doesn't help if you're joining otherwise, like on a 45.
 
Understood. Isn't a closed pattern the starting point for all related discussion?

That's all great for flying a closed pattern, but it doesn't help if you're joining otherwise, like on a 45.
 
As in all things -- it depends, but...

Centerline 1/2 up the strut works in C15x/17x/182/20x series (not all 2xx series have struts).

I never set up further than that, and am usually closer (A continuous slipping turn from downwind to final helps).
 
You can learn to fly a consistent pattern without referencing anything on the airplane. The closer you fly downwind, the more of an angle below the horizon the runway will appear if you look out the left side of the plane. A wide pattern will make the runway appear at a shallower angle below the horizon. This angle below the horizon stuff is the same thing you use when judging when you have reached a point where you can glide power off to a selected touchdown spot, as in doing "simulated engine out" landings. You just have to learn what the angle that works best for you looks like.
 
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The airplane reference point is a good way to develop the picture of depression angle. After you've done it a while, you won't need the reference point. However, until you have that experience-based picture in your mind, the reference point is very helpful.

IOW, if you have to ask the question, you need the answer. If you don't need the answer, you won't be asking the question. ;)
 
And do not forget how crosswind will affect your base leg. If you have a 15 kt xwind and are in a slow airplane, it makes a big difference in where you put your downwind, IMHO.
 
Make sure you're flying a consistent altitude.
Glider people teach the angle, not the offset distance.
I used to teach an airplane reference point for primary students. If your CFI doesn't like the reference point, have him teach you his method and you can correlate it to a reference point.
When teaching ground reference maneuvers, which is the basis for pattern flying, I'd tend to teach flying over a line (imaginary or real) on the ground with reference to the offset, so, I didn't teach a reference point in that regard.
Why don't you explain the method your CFI prefers?
 
The only problem with a reference point on the aircraft (wing for low wing and strut for high wing) is the point has to change based on winds. If you crab toward the runway while maintains the downwind track then the runway must move forward from your reference point. Crabing away from the runway causes the runway to move back.

That said, I suppose it's a good starting point for a primary student.
 
And do not forget how crosswind will affect your base leg. If you have a 15 kt xwind and are in a slow airplane, it makes a big difference in where you put your downwind, IMHO.

This is an interesting assertion. I tend to put my downwind in the same place (I do a relatively close pattern anyway) and simply adjust my crab angle.

What do others think? Move the downwind or not?

John
 
If you're flying a very tight pattern (as some here say is best) then a strong x wind blowing you towards the runway may cause you to not have enough base leg and cause you to blow through final. In that situation it'd make sense to widen out you downwind track.

The pattern I fly isn't an issue. I always have enough room to make the turn. Plus at my speed wind isn't much of a factor unless its REALLY a'blowin.
 
This is an interesting assertion. I tend to put my downwind in the same place (I do a relatively close pattern anyway) and simply adjust my crab angle.

What do others think? Move the downwind or not?

John

Especially for a primary student, IMO. I would like to see primary students flying fairly close patterns because I do not like to wait for them to fly their bomber pattern but they should move it out a bit if they have a strong tailwind on base to give them more time to stay ahead of the airplane. I definitely adjust my pattern for base wind when I am flying the Luscombe as I fly a fairly tight pattern. Also, adjusting for the wind helps the student learn how wind affects him.
 
Can anyone make suggestions that I can use as a starting point (ie midway on wing strut, arm width of light beyond wingtip, etc)?

My humble suggestion and the one I have been using:

Use the length of the runway as your distance guide or ground ruler. You should know its length since that is required by 91.103(b).

Then try to mentally rotate the runway 90 degrees (trickier than it sounds) and estimate what fraction or number of runway lengths out you need to fly. Coincidently, most of the runways I use are around 3000 ft, or about 1/2 nm - just about the generally recommended distance for small planes.

In fact most runways I use are between 3000 and 6000 feet, so simply flying one runway length away on downwind should generally get you in the 1/2 to 1 mile range I've seen recommended.
 
Make sure you're flying a consistent altitude.
Glider people teach the angle, not the offset distance.
I used to teach an airplane reference point for primary students. If your CFI doesn't like the reference point, have him teach you his method and you can correlate it to a reference point.
When teaching ground reference maneuvers, which is the basis for pattern flying, I'd tend to teach flying over a line (imaginary or real) on the ground with reference to the offset, so, I didn't teach a reference point in that regard.
Why don't you explain the method your CFI prefers?

Unable. He was my pre-solo CFI and he doesn't instruct anymore. The law of primacy is affecting my landings. I had somehow found a way to overcome the deficiency but it is not communicable and therefore not reproducable.
 
The only problem with a reference point on the aircraft (wing for low wing and strut for high wing) is the point has to change based on winds. If you crab toward the runway while maintains the downwind track then the runway must move forward from your reference point. Crabing away from the runway causes the runway to move back.

If the centerline is the same place on the strut after 5 or 10 seconds, you're good. If inot, adjust accordingly.
 
Shouldn't the winds also dictate how wide or shallow our downwinds are going to be? Or should you typically always stay the same, and then compensate with earlier or later turns to final, for crosswinds? For strong tailwinds on final, would it be advised to turn sooner onto base? I know when I have a good crosswind I probably will not be using more then 20 degrees of flaps, and in this case I extend my downwind for the higher ground speed.
 
Shouldn't the winds also dictate how wide or shallow our downwinds are going to be? Or should you typically always stay the same, and then compensate with earlier or later turns to final, for crosswinds? For strong tailwinds on final, would it be advised to turn sooner onto base? I know when I have a good crosswind I probably will not be using more then 20 degrees of flaps, and in this case I extend my downwind for the higher ground speed.

I Say again....

If the centerline is the same place on the strut after 5 or 10 seconds, you're good. If not, adjust accordingly (with a wind correction angle).

Further explanation:
If you're being blown towards the runway, the centerline will move down along the strut.

Thus: Adjust course to keep it from moving up (you're being blown away) or down (you're being blown in)
 
Shouldn't the winds also dictate how wide or shallow our downwinds are going to be? Or should you typically always stay the same, and then compensate with earlier or later turns to final, for crosswinds? For strong tailwinds on final, would it be advised to turn sooner onto base? I know when I have a good crosswind I probably will not be using more then 20 degrees of flaps, and in this case I extend my downwind for the higher ground speed.

If you have a tailwind on final, that's called D O W N W I N D
 
If you have a tailwind on final, that's called D O W N W I N D

That's hilarious!

I don't have struts. Low Wing. Where I do my pattern work, at GAI I have some ground reference points that I am used to. Cheating? Maybe. I need to work on judging distance from the runway. Right hand patterns are even more fun with the low wing. I do not know if I am going out to far, but I try to be far enough out in order to see the runway. If there is a good crosswind blowing me towards the runway, I like to be a little wider on my downwind. Is this wrong? It seems like I am still making a u turn because the wind is carrying me over to the centerline faster, when I am at my normal width. Which is between the two churches for 32, or a little to the right of the pond for 14.
 
That's hilarious!

I don't have struts. Low Wing. Where I do my pattern work, at GAI I have some ground reference points that I am used to. Cheating? Maybe. I need to work on judging distance from the runway. Right hand patterns are even more fun with the low wing. I do not know if I am going out to far, but I try to be far enough out in order to see the runway. If there is a good crosswind blowing me towards the runway, I like to be a little wider on my downwind. Is this wrong? It seems like I am still making a u turn because the wind is carrying me over to the centerline faster, when I am at my normal width. Which is between the two churches for 32, or a little to the right of the pond for 14.

No problem. Just take the churches and the pond with you on cross-countries.
 
I don't have struts. Low Wing. Where I do my pattern work, at GAI I have some ground reference points that I am used to. Cheating? Maybe.
If you ain't cheatin', you ain't tryin'.

And yes, you might want to widen out with a crosswind from the pattern side, but the point is that for someone who can't eyeball it like a 10,000-hour veteran, the strut or wing spot cues provide a good starting point from which to adjust.
 
No problem. Just take the churches and the pond with you on cross-countries.

Weight and balance might be an issue. :wink2:

Although I've suggested using the helpful reference ruler every airfield has laid on the ground for you (the runway itself) to measure your distance from the runway, it can be tricky trying to take advantage of it due to perspective. Below is an image created using Google Earth from about pattern height of my home airfield. The runway length is ~3100 ft. Both red lines are ~3100 ft long, and the one perpendicular to the runway shows how far away one would have to be ~1/2 nm from it. The lines don't look equal length thanks to the difference caused by the angled perspective, but they really are equal ground lengths.

When I tried using this technique a few weeks ago, I got close but overestimated the distance, as you can see by this recorded CloudAhoy track (click on Debrief and allow some time for Google Earth app to load):
http://www.cloudahoy.com/cgi-bin/fltShare.cgi?share=19Xrl3Dq9gIy1G2Ox383Ef

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Perhaps Paul Bartorelli can shed some light on it?


Love the epaulets.
 
Weight and balance might be an issue. :wink2:

Although I've suggested using the helpful reference ruler every airfield has laid on the ground for you (the runway itself) to measure your distance from the runway, it can be tricky trying to take advantage of it due to perspective. Below is an image created using Google Earth from about pattern height of my home airfield. The runway length is ~3100 ft. Both red lines are ~3100 ft long, and the one perpendicular to the runway shows how far away one would have to be ~1/2 nm from it. The lines don't look equal length thanks to the difference caused by the angled perspective, but they really are equal ground lengths.

When I tried using this technique a few weeks ago, I got close but overestimated the distance, as you can see by this recorded CloudAhoy track (click on Debrief and allow some time for Google Earth app to load):

Probably not going to work very well on an emergency off airport landing.
 
I Say again....

If the centerline is the same place on the strut after 5 or 10 seconds, you're good. If not, adjust accordingly (with a wind correction angle).

Further explanation:
If you're being blown towards the runway, the centerline will move down along the strut.

Thus: Adjust course to keep it from moving up (you're being blown away) or down (you're being blown in)

I don't think you're addressing Matt's concern. When a strong crosswind exists on the downwind (as evidenced by the need to crab to maintain a constant lateral distance from the runway) it is helpful to adjust your spacing into the wind, especially when the wind is toward the runway. Otherwise you may end up with no room/time for a base leg and/or overshooting the runway centerline.
 
I don't think you're addressing Matt's concern. When a strong crosswind exists on the downwind (as evidenced by the need to crab to maintain a constant lateral distance from the runway) it is helpful to adjust your spacing into the wind, especially when the wind is toward the runway. Otherwise you may end up with no room/time for a base leg and/or overshooting the runway centerline.

If there's a strong crosswind, the strut technique should help the pilot know what sort of wind he's dealing with. In the OP's case, it sounds like he could use the cue.

That info should help prepare for the quick base, but we know that doesn't always happen...

:dunno:
 
J. Bird:

If you're flying along at ~1,000' AGL at 80 knots IAS and want to make a standard-rate 180-turn to fly in the opposite direction, do you know (or can you estimate) the approximate ground track that you would be flying when you roll out of the turn?
 
Probably not going to work very well on an emergency off airport landing.

True - as Jim Meade pointed out, anyone who has had glider training will use sight angles. Gliders trying to fly cross-country have to learn how to land out at sites of uncertain elevation. And often away from objects of known size.

A good book the OP should buy and study is "Glider Basics" by Thomas Knauff. The "Landings" chapter (subtitled "The TLAR, or That Looks About Right technique") should provide some useful insights.
 
So I'm supposed to tape a yardstick to the side window so I can gauge my distance from the runway on downwind - and using power on final approach is somehow bad...

Excuse me for a moment, I need to barf...

OK, back now...
So, do I also tape a yardstick to the wind screen when going cross country so I can tell if I am close enough to an airport to make a unicom call as I cross their airspace?

And how about learning not to depend on my engine for takeoff or cruise flight? I mean if it is bad to adjust your descent to the runway with power it must be bad to use it to adjust the ascent... Golly, what happens if the engine quits on take off and I have become totally dependent on it? Withdrawal can be a *****... Better to be safe and learn to get along without it in the first place...

OK, sarcasm off - and pure peevishness on..
If you actually need to use the strut, or god forbid a ruler, to tell how far you are from the runway you need an optometrist not a ruler... How, the heck do you drive and manage to stop the car before you rear end the car ahead? Do you have a ruler taped to the windshield?

I'm not picking on the person who is asking for advice because his landings have been inconsistent lately... We have ALL been there at some time in our flying career (usually early on)
What I am doing is disagreeing with those who think that telling the student to keep the runway at mid strut is teaching flying... The only way to get good at adjusting your pattern to the wind conditions and being consistent in turning to short final is to get out there and do it, over and over...

I wonder if they can teach you to hit a slider by taping a ruler to your batting helmet...
Or teach golf by taping a ruler to the club...
The best thing for the CFI to do is turn the plane over to the student, fold hands, shut mouth, and watch for traffic while the student learns to fly by actually doing it, over and over...
Yeah, he will be in and out and high and low for a while but hot air from the right seat won't cure that - unless they are flying a balloon...

Two instructors at my local field FBO...
#1 is endlessly helpful to the student, the mouth never stops, and the helping hand on the controls never ceases..
#2 does a quick ground school before each flight then assumes the position of being the safety pilot while the student learns to fly by doing it...
For example: with the very first time student, he shows and tells what each control is for, gets in with the student, guides the student through engine start, then says taxi to the runway and sits there, silent (but alert - he will point if the student is not sure which taxiway to use) Until the student can taxi to the end of the runway - all by himself - he doesn't get to take off... Sometimes this can take 15 or 20 minutes or more the first time... (This is just a brief view of his techniques) He does a ton of talking post flight averaging another hour (no extra charge), but in flight he limits comments to only things the student absolutely needs to hear...

Guess who's students solo earlier, get to their private check ride earlier, and who has never had a student fail to pass on the first try... Of course, #2...
 
Any helicopter or hot-air balloon books he should buy and read as well?


True - as Jim Meade pointed out, anyone who has had glider training will use sight angles. Gliders trying to fly cross-country have to learn how to land out at sites of uncertain elevation. And often away from objects of known size.

A good book the OP should buy and study is "Glider Basics" by Thomas Knauff. The "Landings" chapter (subtitled "The TLAR, or That Looks About Right technique") should provide some useful insights.
 
I can't believe nobody has mentioned to do it by TIME. You want about 20 seconds on base. That is when you really, really need to be able to lookout. Base is about clearing traffic already on final, and looking for the fastmover on straight in, who is still on center freq. You gotta see the guy and base is your last chance.

It happens that 20 seconds at 80 knots is about .4 miles. 15. seconds is 0.3 miles.

Adjust the geographic distance accordingly. If the wind is from the pattern side, the base need be physically longer. If the wind is from the opposite side, it will be geographically shorter. Control of the a/c and stabilization is one thing, but you need enough time to get in a good 10 second scan of final, 'cause guess what, after you make the turn you can't see behind and above you, or even below you.

Everything in the air is about TIME.
 
My rule of thumb is that if it requires a split-S to go from downwind to final, I'm too close. ;-)
 
J. Bird:

If you're flying along at ~1,000' AGL at 80 knots IAS and want to make a standard-rate 180-turn to fly in the opposite direction, do you know (or can you estimate) the approximate ground track that you would be flying when you roll out of the turn?

If you're asking about my ground reference skills, I'd say they need work. Unfortunately this same CFI shorted me there too. He philosophically didn't teach them, so I only did them during my checkride prep with the CFI I finished my PPL with, but that's no excuse.

But yes, I think I can mentally project my path, I have to consciously think about it and adjust for the wind.

Seems I haven't quite mind melded with 4SP yet.
 
All in all. Just need to keep getting up there. And, eventually it should become natural.
 
Sounds to me like you have a good handle on the problem and the training deficiency that caused it, and just need a little help in formulating a plan to fix it. I happen to think the fix is dirt-simple and that you'll have it figured out in about 15 minutes, once you determine a method to test the parameters and consciously study the sight picture and visual cues.

Assuming normal wind speed and velocity, in an uncrowded pattern you might take off and climb to a safe maneuvering altitude and then execute a standard rate 180 turn. When the turn is completed, I think the sight picture will leave no question that your downwind leg is too close too the runway. If you then make a 30-40 degree turn away from the runway and fly for 10-15 seconds and then resume the downwind flight path, you will then be able to SWAG the new offset (pattern size) to see if it looks about right or needs more adjustment. The test will be graded when you turn base and see if your guess was within acceptable limits. Once you see the runway from several different offsets and consciously store that sight picture in memory, everything else is simply fine-tuning.

I wish you were here, we would do it tomorrow morning and then eat some great gumbo at T14. Walt is cooking tonight, tomorrow's cajun food will be as good as it gets.


If you're asking about my ground reference skills, I'd say they need work. Unfortunately this same CFI shorted me there too. He philosophically didn't teach them, so I only did them during my checkride prep with the CFI I finished my PPL with, but that's no excuse.

But yes, I think I can mentally project my path, I have to consciously think about it and adjust for the wind.

Seems I haven't quite mind melded with 4SP yet.
 
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