Weird thought on 360 deg. turns

LongRoadBob

LongRoadBob

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I'm still a student, still learning. Almost through what we call "A-block" (goes up to D before final checkride).

I've done 360 deg. turns, with my instructor, using different bank angles. My instructor was satisfied.

We've been doing other things, slow flight, stalls, etc. but the other night I was thinking about 360 turns and just got a weird uncertainty suddenly. I'm sure this is a stupid thought but...

My thinking went like this. Say we have a heading of 180. I look at the DG, and confirm, and I also look out ahead and see a mast in the distance right ahead of me. I commence the turn. Turning left.

My thought was that as I get near to 3/4 of the way through, my heading is again 180...but I still have 15 degrees more to turn to get back to my start point. Also, just a little over 3/4 of the way through I'm still pretty near a heading of 180, AND that mast is in front of the nose.

Suddenly I wonder if I HAVE actually done a 360, as I'm thinking now it would require that I turn until my heading is Just shy of 090, THEN make a hard right turn until I sight the mast and have heading 180.

Now I'm not sure I have completed a 360 correctly. :) Maybe my instructor is waiting to see if I realize, maybe I have done it correctly. Dunno...

These are the kind of thoughts that come, uninvited, when I'm trying to get to sleep.
 
No. A hard turn is not part of a 360 degree training maneuver.

-Skip
 
???
Start out going 180 pointed at the mast, roll into a lefty loosey turn.
1/4 turn, heading is 90
1/2 turn, heading is 0
3/4 turn heading is 270
as you get close to 180, you roll out and end up on 180 with the mast straight ahead. Assuming the mast is stationary and not on a sailboat that is moving :)
 
Capt. Geoffrey Thorpe said:
???
Start out going 180 pointed at the mast, roll into a lefty loosey turn.
1/4 turn, heading is 90
1/2 turn, heading is 0
3/4 turn heading is 270
as you get close to 180, you roll out and end up on 180 with the mast straight ahead. Assuming the mast is stationary and not on a sailboat that is moving :)
Click to expand...

There is the problem (no...not a sailboat!).

I thought the start of my turn would be from 180 to 090
1/4 through the turn my heading is 0
1/2 through the turn my heading is 270
3/4 180
meeting where I started with a heading of 090 again..mast off to my right at 3 o'clock.

I mean, 3/4 through a turn, the plane wouldn't be facing direct west would it?
 
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Part of learning a 360* turn is beginning the roll out about 10* early so you return wings level on course. If you did it on altitude you should feel a bump from your own wake, at least some of the time.

Imagine a runway heading. You fly on heading, execute a 360* turn, and continue on the same heading.
 
Stewartb said:
Part of learning a 360* turn is beginning the roll out about 10* early so you return wings level on course. If you did it on altitude you should feel a bump from your own wake, at least some of the time.

Imagine a runway heading. You fly on heading, execute a 360* turn, and continue on the same heading.
Click to expand...
I have never felt a bump in a wake from a 360 in a plane. In a boat, sure many times. But a plane?


Sent from my SM-J737T using Tapatalk
 
Not quite sure what you’re talking about, but my guess is that your mind is playing tricks on you. Mark your heading prior to beginning the steep turn and then watch that heading come back around as you go through the turn.
 
LongRoadBob said:
There is the problem (no...not a sailboat!).

I thought the start of my turn would be from 180 to 090
1/4 through the turn my heading is 0
1/2 through the turn my heading is 270
3/4 180
meeting where I started with a heading of 090 again..mast off to my right at 3 o'clock.

I mean, 3/4 through a turn, the plane wouldn't be facing direct west would it?
Click to expand...

Your turn starts as soon as you move the control. So if you start at 180, that's where you should be rolled out and level when done with a 360 turn. I feel the bump just about every time I do a 360 turn. So start at 180, turn left, 3/4 through you will be at 270 and thinking "aha, this turn is almost done, better start thinking about rolling out" which should be done so you are wings level at 180. If you roll out at 090 you have done a 450 degree turn ( or a 90 degree turn).
 
LongRoadBob said:
I'm still a student, still learning. Almost through what we call "A-block" (goes up to D before final checkride).

I've done 360 deg. turns, with my instructor, using different bank angles. My instructor was satisfied.

We've been doing other things, slow flight, stalls, etc. but the other night I was thinking about 360 turns and just got a weird uncertainty suddenly. I'm sure this is a stupid thought but...

My thinking went like this. Say we have a heading of 180. I look at the DG, and confirm, and I also look out ahead and see a mast in the distance right ahead of me. I commence the turn. Turning left.

My thought was that as I get near to 3/4 of the way through, my heading is again 180...but I still have 15 degrees more to turn to get back to my start point. Also, just a little over 3/4 of the way through I'm still pretty near a heading of 180, AND that mast is in front of the nose.

Suddenly I wonder if I HAVE actually done a 360, as I'm thinking now it would require that I turn until my heading is Just shy of 090, THEN make a hard right turn until I sight the mast and have heading 180.

Now I'm not sure I have completed a 360 correctly. :) Maybe my instructor is waiting to see if I realize, maybe I have done it correctly. Dunno...

These are the kind of thoughts that come, uninvited, when I'm trying to get to sleep.
Click to expand...
Totally confused. Are you talking about compass lead/lag?
 
holy crap! Halfway though your turn is 360/0 not 270... Put a compass app on your phone...while holding the phone, face the refridgerator and note the compass heading... spin around to the right and look at the fridge again... is the compass reading the same as when you started? all is right in the universe..
 
PaulS said:
Your turn starts as soon as you move the control. So if you start at 180, that's where you should be rolled out and level when done with a 360 turn. I feel the bump just about every time I do a 360 turn. So start at 180, turn left, 3/4 through you will be at 270 and thinking "aha, this turn is almost done, better start thinking about rolling out" which should be done so you are wings level at 180. If you roll out at 090 you have done a 450 degree turn ( or a 90 degree turn).
Click to expand...

I guess this is where I'm confusing things.

3/4 through the plane will be at 270 of the full turn, but the plane heading is 180, right?

I mean, take a circle, and a pen (representing the plane) pretend you are north, and have it facing directly away from you. Heading 180. Now turn it, to make a circle. First it is pointing at 90 degrees, when it is at the point (IN the circle) of 90 degrees, the plane (pen) is pointing directly at you (north) but has only completed 1/4 of the circle.

Continue on, the pen is at the nearest point of the circle to you, Half circle, but is now pointing directly right...one quater turn more it is pointing 180 (away from you) but to complete it we have to move it the last 1/4 turn and it is facine then directly left from your viewpoint.
 
The OP problem is that you are imagining flying through the center of the circle and starting your turn, beginning at the 12 o'clock position. Then when you get 3/4 of the way around the circle you are pointing the original direction.

But you're entering the turn tangent to the arc at the 3 o'clock position and fly a circle back to the 3 o'clock.

And yes, done properly you'll fly through your own wake. If you look out the back window of a C150/C152 at that moment you'll see the tail shake more than you might think it should.
 
FlySince9 said:
holy crap! Halfway though your turn is 360/0 not 270... Put a compass app on your phone...while holding the phone, face the refridgerator and note the compass heading... spin around to the right and look at the fridge again... is the compass reading the same as when you started? all is right in the universe..
Click to expand...

Nope. The plane is not spinning on its axis, it is turning. If I am making a circle in front of the fridge, and I turn right, I only made a right turn. If I am waling a circle...by the time I am 1/4 of the way through I am facing directly away from the fridge.

Nobody claimed the compass is not moving.
 
You seem to have a misunderstanding of those 360 little marks on a compass.
 
If my pen is facing north when I begin the turn I’m 1/4 through my turn when I’m pointing to 90 degrees. 1/2 done with turn at 180 degrees. 3/4 done at 270. And finished when heading north again.


You’re over thinking.
 
tspear said:
I have never felt a bump in a wake from a 360 in a plane. In a boat, sure many times. But a plane?


Sent from my SM-J737T using Tapatalk
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oh, yah...quite a few times...once I learned to do them properly. to the student...you might need a little down pressure on the yoke to keep the nose from rising as you roll out of the turn.
 
btw, I'm kinda leaning towards troll now...….sorry.
 
eman1200 said:
only if you do them correctly.
Click to expand...
I do them correctly, on altitude, full circle many times. First in a Cirrus SR20, then an Aerostar, and now a Cirrus SR22.
In fact I just did a series of them for a BFR and IPC in a Cirrus SR20 then an SR22. Not once did I feel a wake.
Also, I am curious about the wake from a physics standpoint. I was taught that wing tip vortexes descend as they lose energy unless being lifted by convective air. In a standard rate turn, it takes two minutes to get back to the same spot. If you maintain altitude, and the vortex has descend how do you hit the wake?

Tim
 
rk911 said:
oh, yah...quite a few times...once I learned to do them properly. to the student...you might need a little down pressure on the yoke to keep the nose from rising as you roll out of the turn.
Click to expand...

Every year, I practice them until I stay on altitude from start through finish (in smooth air, if bumpy I give my self an excuse). In order to maintain lift and stay on altitude, you must adjust pitch, simple physics.

Tim
 
tspear said:
I do them correctly, on altitude, full circle many times. First in a Cirrus SR20, then an Aerostar, and now a Cirrus SR22.
In fact I just did a series of them for a BFR and IPC in a Cirrus SR20 then an SR22. Not once did I feel a wake.
Also, I am curious about the wake from a physics standpoint. I was taught that wing tip vortexes descend as they lose energy unless being lifted by convective air. In a standard rate turn, it takes two minutes to get back to the same spot. If you maintain altitude, and the vortex has descend how do you hit the wake?

Tim
Click to expand...
I think most people were referring to steep turn 360's (a PPL and CPL maneuver at differing angles), not standard rate.
 
If you’ve ever heard a discussion about “moose stalls” in Cubs the interception of the plane’s own wake is often considered a contributor to upsetting the turning plane. That assumes the plane is continuing the turn through 360* so not directly applicable to this topic. Racetrack patterns are taught to reduce fixation on one point and to allow crossing the wake on a perpendicular track. One 270* turn followed by an opposite direction 270* turn. You should feel your wake in that maneuver.

The notion that all wake turbulence goes down isn’t correct. One alarming wake event I’ve had was in same altitude-same path approx 3/4 mile trail of a Cessna 206. I saw him there but never expected to get tossed like I did.
 
LongRoadBob said:
Nope. The plane is not spinning on its axis, it is turning. If I am making a circle in front of the fridge, and I turn right, I only made a right turn. If I am waling a circle...by the time I am 1/4 of the way through I am facing directly away from the fridge.

Nobody claimed the compass is not moving.
Click to expand...

Bob, you are overthinking this. A 360 degree turn means that you turn your compass (or better yet your dg) 360 degrees so that you end up on the same heading and if no wind on the same track when you roll out of the turn as when you started. That's all you should care about.

The 360 turn is off to the side of the track in the direction in which you turn. So at 180 of a right turn you are offset the diameter of the turn facing the opposite direction of which you started. You do not come back through your track at 180 degrees, this is what is screwing you up ( and me too for a second as I thought about this). So in your fridge example, (which really doesn't work, because you can't go through the fridge, but lets assume you can walk through the fridge), you don't pivot in front of the fridge, you walk the turn radius until you are facing 90 degrees, at which point your left shoulder is facing the direction you were standing in front of the fridge, offset by the radius and one radius behind the fridge. Then you again on the radius walk another 90 degrees until you are at 180 degrees. At this point your back is facing the same direction as the fridge, one diameter offset from the fridge, but directly in line with it. Then you walk another 90 degrees to 270. At this point you are offset one radius to side of the fridge, one radius in front of it and you are facing with your right shoulder toward the direction of the fridge. From there you walk the final 90 degrees to 360, at this point you are in front of the fridge again facing it.

A picture is worth a thousand words, but I'm too lazy to draw it for you.
 
I'm confused. What's the compass or the DG have to do with a 360 turn? Are you flying IFR? No? Then look at the beautiful scenery out the window, pick out something distinctive and do a 360. Keep looking out the window, you should be able to do the entire maneuver without looking inside the cockpit.

Ok, I admit to sneaking a peek at the altimeter to make sure I'm not changing altitude and the AI to verify bank angle. If you insist on using the DG, then just set the heading bug and look for the bug to come back around.
 
Pick a spot on the horizon. Forget the compass for now.
 
tspear said:
I have never felt a bump in a wake from a 360 in a plane. In a boat, sure many times. But a plane?


Sent from my SM-J737T using Tapatalk
Click to expand...

Do a steep turn correctly and you should definitely hit your wake and feel a small bump.
 
As noted by others... don't look at the compass or the DG. Look out the window. Removes all confusion. And yes, if you turn and maintain altitude the way you should you'll run into your own wake.
 
bflynn said:
I'm confused. What's the compass or the DG have to do with a 360 turn? Are you flying IFR? No? Then look at the beautiful scenery out the window, pick out something distinctive and do a 360. Keep looking out the window, you should be able to do the entire maneuver without looking inside the cockpit.

Ok, I admit to sneaking a peek at the altimeter to make sure I'm not changing altitude and the AI to verify bank angle. If you insist on using the DG, then just set the heading bug and look for the bug to come back around.
Click to expand...

DaleB said:
As noted by others... don't look at the compass or the DG. Look out the window. Removes all confusion. And yes, if you turn and maintain altitude the way you should you'll run into your own wake.
Click to expand...

I didn't say "look only at the dg", of course you look outside. But at the end of the day it is a 360 turn, not a 355 or a 365 degree turn. Every time I've done it if I'm not straight and level on the heading I started I get a comment from the instructor, they are picky that way.
 
tspear said:
I have never felt a bump in a wake from a 360 in a plane. In a boat, sure many times. But a plane?


Sent from my SM-J737T using Tapatalk
Click to expand...

I have a few times, in steep 360's. If you hold your altitude and complete the turn where you started in the air, you run through your own wake and get a little jolt, usually right before or as you level your wings. First time it happens is freaky.

I imagine in a slower, less banked 360, you may not hit your own wake because the longer time will allow the wake to dissipate.
 
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