Lazy 8's and visual reference

labbadabba

labbadabba

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labbadabba
Getting my act together and finally getting started on my commercial maneuvers. Lazy 8's seem pretty simple in practice. One question I have though is about visual references.

According to what I'm reading, it is important to establish a 45-degree point, a 90-degree point, and a 135-degree point to use as checkpoints as you complete the maneuver. Establishing those visual landmarks shouldn't be too difficult for the entry and the first turn but what about the 2nd half of the maneuver?

It seems like it would be tricky to identify 45,90,135 degree points for the other turn. Would it just be easier to use the heading indicator?
 
Just tell the DPE your CFI didn't go over those....
 
Just use one point. At the start and 180 degrees its off your wing, at 90 you're head on, the 45 and 135 degree points in the maneuver you just have to "guess". Example the 45 degree point might be right in front of the A pillar or inline with a vent or something.

Its an outside reference maneuver so don't get too caught up in flying by the instruments.
 
You pick one "good" landmark as distinct and distant as possible and you use the same one at the 0, 90, and 180 degree points, just with different parts the of the airplane -- left wing, nose, then right wing. For the second turn, it's still the same landmark -- right wing, nose, left wing.

The 45/135 degree points are less important and can be picked as you need them. You don't have to pick them out ahead of time. I pick new ones each turn. Since you're only going to be looking at such a point for 1/8th of a turn it doesn't need to be something conspicuous.
 
Okay, so I got a chance to fly a bit. I noticed that if I base my turn off the AI and keep steady pitch input and steady bank input I hit my visual marks without trying to hit them if that makes sense.

So rather than aiming for these landmarks I just use them as checkpoints along the way.

One thing I did notice is that I tend to end my turns a bit high. The turn from level to 30 degrees bank seems nice and slow but once I hit 30 degrees, the nose really slices down fast and I have to be a little more active with my control input, particularly pitching down and immediately shallowing my bank lest I blow thru the 135 degree point.

Is this normal?
 
labbadabba said:
Okay, so I got a chance to fly a bit. I noticed that if I base my turn off the AI and keep steady pitch input and steady bank input I hit my visual marks without trying to hit them if that makes sense.

So rather than aiming for these landmarks I just use them as checkpoints along the way.

One thing I did notice is that I tend to end my turns a bit high. The turn from level to 30 degrees bank seems nice and slow but once I hit 30 degrees, the nose really slices down fast and I have to be a little more active with my control input, particularly pitching down and immediately shallowing my bank lest I blow thru the 135 degree point.

Is this normal?
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I'm not sure what "normal" is, but to me lazy 8s are a good way to demonstrate positive static stability in pitch. If you do a smooth pitch-up, the nose will naturally want to go down the same amount below the horizon.

The lateral stability does something similar in roll...the airplane naturally wants to go back to wings level. If you let the airplane do its thing with just a little guidance, it doesn't have the tendency to roll out early that a lot of people have when doing the maneuver.

Back in the day, I could do lazy 8s by flying through the first 45 degrees, to maximum pitch, give the ailerons a nudge to start the rollout, and take my hand off the yoke through the 90 degree point; at that time, all I had to do was apply roll input the other direction, with just a bit of back pressure approaching the 135 degree point, nudge the aileron back towards wings level, and let go again. Of course, rudder inputs were required all the way through to keep coordinated.
 
You can definitely do them with just a 90 degree point, but assuming you want to use 45, 90 and 135 references... just re-use the same points (since the second half of the maneuver is done in the opposite direction). For instance, if you start to the left you'll have reference points at 45, 90 and 135. Then, once you're at the 180 point you'll roll to the right and your original 135 point becomes your 45. The 90 stays the same. And your original 45 point becomes your 135.
 
tlglenn said:
I like to use one long, straight, road and start the maneuver as I cross perpendicular to the road.
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That’s perfect for S-turns across a road.

For a Lazy 8, however, you’d have to make sure that road was perfectly aligned either into or with the wind. Otherwise in your attempt to keep crossing the road at right angles, wind drift will mess up the symmetry of the maneuver.

Remember the “8” refers to the path of the nose in relation to the point on the horizon, NOT the plane’s path over the ground.
 
It's not a ground reference maneuver so I don't care about ground track in relation to the road, but it provides a handy way of knowing when you've reached 45, 90, 135, and 180. The road will be in your peripheral vision and be seen when scanning for traffic.
 
Whatever works.

On a windy day, I can see those angular references changing a bit as you drifted downwind, but that may be more of a theoretical issue than a practical one.

I personally prefer to use the horizon point to establish those angles.
 
Upon review of the AFH, I stand corrected.

“In an attempt to simplify the discussion about this maneuver, the lazy eight can be loosely described by the ground reference maneuver, S-turns across the road. Recall that S-turns across the road are made of opposing 180° turns. For example, first a 180° turn to the right, followed immediately by a 180° turn to the left. The lazy eight adds both a climb and descent to each 180° segment. The first 90° is a climb; the second 90° is a descent. [Figure 9-4]”

“Loosely described” gives me some cover, but the figure referenced does use a road as a ground reference.

I could have sworn I learned differently.

Anyway, here’s me practicing for my CFI reinstatement:


Lazy 8’s begin :45 in. I was using the vanishing point of US64 headed west as my reference point, making no effort to stay over the highyway below.
 
When I was doing those I remember the instructor telling me to pick out 45, 90, and 135 degree points. No way I could do that in my head. I know this is "wrong" by the book and according anybody giving instruction but the only way it worked for me was to use heading indicator. Id set my entry heading and with the heading bug and via a quick glance I know when I was @ my 90 and 180 degree points. Remember the PTS doesn't comment where you are at the specified points. Only the 180 degree point and you are 30 degree bank @ your steepest point:

Complete the maneuver in accordance with the following:
a. Approximately 30° bank at the steepest point
b. Constant change of pitch and roll rate and airspeed
c. Altitude at 180° point, ±100 feet from entry altitude
d. Airspeed at the 180° point, ±10 knots from entry airspeed
e. Heading at the 180° point, ±10 degrees
[\QUOTE]
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neilw2 said:
When I was doing those I remember the instructor telling me to pick out 45, 90, and 135 degree points. No way I could do that in my head. I know this is "wrong" by the book and according anybody giving instruction but the only way it worked for me was to use heading indicator. Id set my entry heading and with the heading bug and via a quick glance I know when I was @ my 90 and 180 degree points. Remember the PTS doesn't comment where you are at the specified points. Only the 180 degree point and you are 30 degree bank @ your steepest point:
Click to expand...

Honestly, while I've been practicing, I've found using the DG much more useful, particularly since I'm already cross-checking my AI for bank angle.
 
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