Actual track of lazy 8s

Archimago

Archimago

Pre-takeoff checklist
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Archimago
I have been practicing my lazy 8s but when I view them on FlyQ afterwards the shape of the track does not look like they do in the pictures…ie perfect semi circles. As I do the maneuver it seems like the first 90 degrees happens faster and more acutely then the second 90. My track looks something like elongated “u” shapes.

also the second 90 is challenging. If I release the bank to get 15 degrees at the 135 mark it takes a long time to get to the 180….if I hold the bank tight a little longer it seems to work out but then the bank angle isn’t “continuously changing”
 
Lazy 8’s are NOT a ground reference maneuver. So give zero thought as to the track of the plane over the ground.

The “8” instead refers to the path/motion of the nose of the plane reference the horizon. The ground track is irrelevant and will vary wildly depending on the wind.

But I agree in that for me the second half is more challenging, always seeming much more prolonged than the first half. My out-of-practice, somewhat pathetic attempt starts at about :45 in here:


But makes me want to go practice a few next time I’m up in the Sky Arrow!
 
When I was practicing - and during the checkride - I set my heading bug to the wind direction. Then, put the bug on the left wing. This way, depending on the wind speed, you will more or less stay in close to your initial position, since your turns are always into the wind. When you look at the track, it will be closer to an "8", but probably never really be an "8" unless your wind is over 50K. Don't rush it - it is as the name implies. Lazy!!
 
Archimago said:
I have been practicing my lazy 8s but when I view them on FlyQ afterwards the shape of the track does not look like they do in the pictures…ie perfect semi circles. As I do the maneuver it seems like the first 90 degrees happens faster and more acutely then the second 90. My track looks something like elongated “u” shapes.

also the second 90 is challenging. If I release the bank to get 15 degrees at the 135 mark it takes a long time to get to the 180….if I hold the bank tight a little longer it seems to work out but then the bank angle isn’t “continuously changing”
Click to expand...

The ground track is irrelevant. The last 45 degrees of the maneuver takes the longest because turn rate at a given bank angle is inversely proportional to true airspeed and that part of the maneuver has the highest airspeed. There is no requirement for the amount of time to be symmetrical and physics dictates that it won't be. Only the pitch and bank should be symmetrical.
 
midlifeflyer said:
Speaking of "Lazy," I love Jason Miller's take on the maneuver.
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This is the single best aviation video on YouTube. It made Lazy 8's not only click for me, but fun enough that I fly them just for fun sometimes. Like @EdFred said above, the maneuver is extremely lazy. The purpose of the maneuver is to demonstrate and understand how the wings work, and if you do the maneuver right the wing will do nearly all the work for you.

As others have said, the ground track doesn't matter and isn't connected with the name. You judge and debrief a Lazy 8 by looking out the windshield (and at the altimeter and heading indicator).
 
Hi everyone.
I do agree that L8 are fun and you can do them as fun, but there are other elements of the maneuver, if it's to be considered done properly, that are not being considered in this video.
Best is the read and understand All that is involved, speeds, angle of bank... start with the video and refine it to the proper technique and requirements.
 
midlifeflyer said:
Speaking of "Lazy," I love Jason Miller's take on the maneuver.
Click to expand...

No. It's not even close to being done properly, at least with respect to how the FAA wants it preformed for a commercial practical test. He reaches 30 degrees of bank after only 15 degrees of heading change. Not correct.
 
EdFred said:
The planes I've done them in, I always figured they were lazy because after the initial bank/climb I don't do a damn thing until I'm leveling out at the finish.
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Good news is the FAA took the “eight on its side on the horizon” out of the AFH, because nobody read it anyway. ;)
 
midlifeflyer said:
Speaking of "Lazy," I love Jason Miller's take on the maneuver.
Click to expand...
That is a good video and really helpful for the first 90...but it seems like the second half is a little glossed over
 
Keep practicing. It will come in handy once you make captain on a 777 and you have to do the Lazy 8 to gain clearance into Tokyo.
 
bluesideup said:
Hi everyone.
I do agree that L8 are fun and you can do them as fun, but there are other elements of the maneuver, if it's to be considered done properly, that are not being considered in this video.
Best is the read and understand All that is involved, speeds, angle of bank... start with the video and refine it to the proper technique and requirements.
Click to expand...
Yes, we can always make things more complicated.
 
Archimago said:
That is a good video and really helpful for the first 90...but it seems like the second half is a little glossed over
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Yep. It's not clear how they level out without any aileron input. Maybe they start the bank, then neutralize the ailerons and let the initial bank continue as the airspeed decreases. Still seems like you should roll out at the end with ailerons.
 
MauleSkinner said:
More pitch generally makes them easier, too.
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Agree,
Seems like a lot of pilots I do them with seem to ignore this line from the Airplane Flying Handbook.
"The airspeed should be at its minimum, just about 5 to 10 knots above stall speed,"

I actually find them a bit easier when you get the speed slowed down as it increases the turn rate at the 90 degree point.

I generally like the Jason Miller video mentioned above, it illustrates the basic Idea that airplane pretty much naturally wants to do much of the Lazy 8 maneuver. But tends to minimize the small minor inputs that need to be constantly monitored and made to make the Lazy 8 meet the FAA standards.


Brian
CFIIG/ASEL
 
dmspilot said:
No. It's not even close to being done properly, at least with respect to how the FAA wants it preformed for a commercial practical test.
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brcase said:
But tends to minimize the small minor inputs that need to be constantly monitored and made to make the Lazy 8 meet the FAA standards.
Click to expand...

Fortunately or unfortunately, depending on your perspective, the Commercial ACS doesn't really provide a lot of detail as to how the maneuver is to be completed. If I was a DPE, I'd be hard-pressed to NOT give the applicant quite a bit of latitude as long as they were within the ACS requirements. Of course, that may be partially why I never intend to become a DPE.*

These are the main requirements:

upload_2022-12-23_10-56-45.png

- I'm not sure what "approximately" 30 degrees means. 25? 35? 40?
- "Constant" change is pretty up for interpretation too.
- All the others are just "end states" for the completion of each 180 and don't pertain to what you're doing during the course of that 180.

As a CFI, I really don't like teaching these. Most people tend to over-think them, yes, but also there is the constant question of "why am I spending all this time and money learning this? What practical application does it have?" And to that, I have no real satisfying answer. "It builds skill and coordination" doesn't work more than once or twice.

* I laughed when I wrote that. I wonder if anybody has ever unintentionally become a DPE.
 
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RussR said:
Fortunately or unfortunately, depending on your perspective, the Commercial ACS doesn't really provide a lot of detail as to how the maneuver is to be completed. If I was a DPE, I'd be hard-pressed to NOT give the applicant quite a bit of latitude as long as they were within the ACS requirements. Of course, that may be partially why I never intend to become a DPE.*

These are the main requirements:

View attachment 113315

- I'm not sure what "approximately" 30 degrees means. 25? 35? 40?
- "Constant" change is pretty up for interpretation too.
- All the others are just "end states" for the completion of each 180 and don't pertain to what you're doing during the course of that 180.

As a CFI, I really don't like teaching these. Most people tend to over-think them, yes, but also there is the constant question of "why am I spending all this time and money learning this? What practical application does it have?" And to that, I have no real satisfying answer. "It builds skill and coordination" doesn't work more than once or twice.

* I laughed when I wrote that. I wonder if anybody has even unintentionally become a DPE.
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You should hear the FAA backtrack over themselves when we do our annual examiner training. :rolleyes:

As far as why learn Lazy 8s, my response to that one is more about understanding and applying static and dynamic stability concepts.
 
RussR said:
Fortunately or unfortunately, depending on your perspective, the Commercial ACS doesn't really provide a lot of detail as to how the maneuver is to be completed.
Click to expand...

That is what this is for:

Screen Shot 2022-12-23 at 12.18.40 PM.png

Using your argument, you could just make up your own maneuver so long as it meets the ACS criteria.
 
RussR said:
Fortunately or unfortunately, depending on your perspective, the Commercial ACS doesn't really provide a lot of detail as to how the maneuver is to be completed. If I was a DPE, I'd be hard-pressed to NOT give the applicant quite a bit of latitude as long as they were within the ACS requirements. Of course, that may be partially why I never intend to become a DPE.*
Click to expand...
Most DPE I've discussed the issue with say they do give a lot of latitude on lazy 8s.
 
By "leeway" I think something like a range of 10-20 degrees of bank angle at the 45° points would be reasonable. Not reasonable is reaching your max bank angle after less than 20 degrees of heading change. Our local DPE has stopped testing them (the DPE can choose between chandelles and lazy eights) since no one does them correctly anymore. Better than having a high fail rate, I guess.
 
dmspilot said:
By "leeway" I think something like a range of 10-20 degrees of bank angle at the 45° points would be reasonable. Not reasonable is reaching your max bank angle after less than 20 degrees of heading change. Our local DPE has stopped testing them (the DPE can choose between chandelles and lazy eights) since no one does them correctly anymore. Better than having a high fail rate, I guess.
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Definitely. "Leeway" doesn't mean doing something totally different.
 
dmspilot said:
That is what this is for:

View attachment 113320

Using your argument, you could just make up your own maneuver so long as it meets the ACS criteria.
Click to expand...

Obviously that's exaggerating, but my point was that (as discussed subsequently), the DPEs have a lot of leeway on this maneuver. The fortunate thing about having that leeway is a reasonable DPE can feel okay accepting an imperfect maneuver as long as it meets his or her own personal standards. The unfortunate thing about that leeway is that if the maneuver is poorly done, there may not be anything definite to point to IF it still met the stated ACS standards. Even the AFH description uses words like "should" "approximately" and "about" throughout the paragraphs, not "must" or "shall".

I much prefer the Chandelle as an exercise in control inputs, coordination, etc.
 
RussR said:
Obviously that's exaggerating, but my point was that (as discussed subsequently), the DPEs have a lot of leeway on this maneuver. The fortunate thing about having that leeway is a reasonable DPE can feel okay accepting an imperfect maneuver as long as it meets his or her own personal standards. The unfortunate thing about that leeway is that if the maneuver is poorly done, there may not be anything definite to point to IF it still met the stated ACS standards. Even the AFH description uses words like "should" "approximately" and "about" throughout the paragraphs, not "must" or "shall".

I much prefer the Chandelle as an exercise in control inputs, coordination, etc.
Click to expand...
Keep in mind the unpublished, but widely accepted, FAA definition of “should” is basically you’d better have a really good excuse not to.
 
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