Commercial maneuvers.

Discussion in 'Pilot Training' started by lancie00, Jan 15, 2020 at 1:55 PM.

  1. lancie00

    lancie00 Line Up and Wait

    Joined:
    May 12, 2016
    Messages:
    747
    Display Name:

    Display name:
    lancie00
    I'm starting to work on my commercial maneuvers and wondered a couple things.

    How far apart are your pylons when doing 8's on pylons? I think mine are 1/2 mile. Pretty easy to tell here in Iowa where there's a field line every 1/2 mile.

    Also, how big of a radius should be used for steep spirals? I think I've been using about a 1/4 mile radius.

    I know I should ask my CFI but he flies big iron and is gone most of the time. Besides, he's not really "up to speed" on small GA maneuvers.
     
    Last edited: Jan 15, 2020 at 2:04 PM
  2. midlifeflyer

    midlifeflyer Touchdown! Greaser!

    Joined:
    May 25, 2006
    Messages:
    10,500
    Location:
    Chapel Hill NC
    Display Name:

    Display name:
    Mark
    Um... 8s on pylons and lazy 8s are two completely different maneuvers.
     
  3. lancie00

    lancie00 Line Up and Wait

    Joined:
    May 12, 2016
    Messages:
    747
    Display Name:

    Display name:
    lancie00
    You're right, my bad. I meant 8's on pylons and have changed my original post. Thanks
     
  4. dtuuri

    dtuuri En-Route

    Joined:
    Apr 21, 2011
    Messages:
    3,824
    Location:
    Madison, OH
    Display Name:

    Display name:
    dtuuri
    Um, no pylons for lazy 8s.

    Depends on wind velocity and steepest bank.
     
  5. dtuuri

    dtuuri En-Route

    Joined:
    Apr 21, 2011
    Messages:
    3,824
    Location:
    Madison, OH
    Display Name:

    Display name:
    dtuuri
    Three seconds.
     
  6. midlifeflyer

    midlifeflyer Touchdown! Greaser!

    Joined:
    May 25, 2006
    Messages:
    10,500
    Location:
    Chapel Hill NC
    Display Name:

    Display name:
    Mark
    Have you started by reading the description of these maneuvers in the FAA's Airplane Flying Handbook? Dave didn't pull that 3 seconds out of his hat:
    The distance between the pylons should allow for the straight-and-level flight segment to last from 3 to 5 seconds.​
     
  7. lancie00

    lancie00 Line Up and Wait

    Joined:
    May 12, 2016
    Messages:
    747
    Display Name:

    Display name:
    lancie00
    Yes I have.
     
  8. ja_user

    ja_user Pattern Altitude

    Joined:
    Nov 22, 2010
    Messages:
    1,862
    Location:
    Kixd
    Display Name:

    Display name:
    Sam
    On the spiral, it doesn't matter how far away you are. If you need a place to start until you get it right, try 1/4 mile, but don't be suprised when you can't see it until you are in the bank.

    Just start on the downwind leg and don't go over 60degree bank.

    No one will be impressed if your steep spiral involves a 15 degree bank at the steepest point
     
  9. midlifeflyer

    midlifeflyer Touchdown! Greaser!

    Joined:
    May 25, 2006
    Messages:
    10,500
    Location:
    Chapel Hill NC
    Display Name:

    Display name:
    Mark
    Then you know the distance between pylons is 3-5 seconds so it, like pivotal altitude is dependent on groundspeed.

    good reasons to start, not end, with a CFI.
     
  10. midwestpa24

    midwestpa24 Pattern Altitude

    Joined:
    Mar 4, 2016
    Messages:
    1,511
    Display Name:

    Display name:
    midwestpa24
    https://www.youtube.com/user/undaerocast/videos

    Check out some of the videos UND has put together. They do a pretty good job going through each of the commercial maneuvers. Helped me get the concepts years ago before pursuing mine.
     
  11. AggieMike88

    AggieMike88 Touchdown! Greaser!

    Joined:
    Jan 13, 2010
    Messages:
    17,709
    Location:
    Denton, TX
    Display Name:

    Display name:
    The original "I don't know it all" of aviation.
    Pylon 8's have three points to consider. Left Pylon, center/crossing point, Right Pylon.

    The pylons should be a bout 1/2-mile from the center. Making them 1 mile apart from each other.

    The big secret on Pylon 8's is
    1. having your Pivotal Altitudes already calculated and written on your kneeboard.
    2. knowing where your wind is coming from so you can put the airplane headed toward the crossing point with the wind over your left shoulder.
    3. Having an instrument showing you your Ground Speed so you can quickly look at your Pivotal Altitude table and get there.
    4. Setting your power to a reasonable amount for a reasonable speed. For the 172 I did my check ride in, 2200 RPM was a comfortable spot.
    5. After doing the left turn and passing your crossing point, count 7 potatoes or Mississippi's. Then "drop" your wing tip and start your right turn around that pylon.

    I attached my lesson for Pylon 8's if you're interested.


    Steep Spirals are one of the easiest once you get it figured out. It's essentially a turn around a point while descending at idle power. And if you study the Turn around A Point details in the AFM, it will make this maneuver much easier to understand and do.

    Here's how I do them.....
    1. Select the point you're going to spiral around. Best point is a four way road intersection. The 4 roads leading away from the intersection make it simple to keep situational awareness
    2. Set up for the entry with the wind behind you. Then you already know you need to use a steeper bank to start because the wind is going to "blow you away from" the intersection.
    3. Fly to the intersection so that you will put your left main tire right on that spot. This gets you into a good point laterally.
    4. When you are a few airplane lengths away from the spot, pull power, hold altitude, and let the airplane slow to best glide speed. Trim as needed
    5. When the tire "crosses" the point, start your left turn, steepest bank. Adjust minor trim to hold best glide as needed.
    6. As you turn each 90 degrees (cross each road), adjust your bank angle as needed to keep the same distance.
    7. Keep an eye on your airspeed. It's very easy to do the common error of pitching up or down. You want to maintain best glide.
    8. Passing through 90-degrees to 270-degrees, you will be shallowing your bank as you transition from being blown away from the point to being blown into it.
    9. Keep monitoring your distance from the point and adjust bank as needed. Keep maintaining best glide speed.
    10. As you pass back through 360-degrees, clear your engine by advancing throttle to full and then pulling it back out.
    11. ((secret tip)) there is no ACS guidance on how quickly you move the throttle to clear the engine, so you can use this to arrest some of the sink and gain a smidge of altitude.
    12. Rinse repeat through two more full turns.

    And it is very possible to get three full turns in less than 2,000 feet altitude. At first you won't think so... but with practice you can.
     

    Attached Files:

    Justin M likes this.
  12. AggieMike88

    AggieMike88 Touchdown! Greaser!

    Joined:
    Jan 13, 2010
    Messages:
    17,709
    Location:
    Denton, TX
    Display Name:

    Display name:
    The original "I don't know it all" of aviation.
    I try to make my lazy 8's so lazy...... they are actually a 7.
     
    murphey and midlifeflyer like this.
  13. AggieMike88

    AggieMike88 Touchdown! Greaser!

    Joined:
    Jan 13, 2010
    Messages:
    17,709
    Location:
    Denton, TX
    Display Name:

    Display name:
    The original "I don't know it all" of aviation.
    And I can't be the only one who hasn't wondered about Eights on these guys...

    [​IMG]
     
  14. GeorgeC

    GeorgeC En-Route

    Joined:
    Dec 5, 2010
    Messages:
    2,883
    Display Name:

    Display name:
    GeorgeC
  15. AggieMike88

    AggieMike88 Touchdown! Greaser!

    Joined:
    Jan 13, 2010
    Messages:
    17,709
    Location:
    Denton, TX
    Display Name:

    Display name:
    The original "I don't know it all" of aviation.
  16. denverpilot

    denverpilot Tied Down

    Joined:
    Nov 8, 2009
    Messages:
    51,216
    Location:
    Denver, CO
    Display Name:

    Display name:
    DenverPilot
    [QUOTE="AggieMik
    1. having your Pivotal Altitudes already calculated and written on your kneeboard.
    2. knowing where your wind is coming from so you can put the airplane headed toward the crossing point with the wind over your left shoulder.
    3. Having an instrument showing you your Ground Speed so you can quickly look at your Pivotal Altitude table and get there.
    4. Setting your power to a reasonable amount for a reasonable speed. For the 172 I did my check ride in, 2200 RPM was a comfortable spot.
      [/QUOTE]

      Just as a point of order, other than picking a reasonable speed, I had none of those things. I had a rough knowledge of the pivotal altitude so you don’t start at some wildly high altitude...

      But it’s a visual maneuver. You can fix everything by just looking out the window.

      You definitely don’t need the wind on any particular shoulder, for example. And nothing I flew the checkrides in had a groundspeed indicator.

      Very difficult to type up how to do this here with one thumb, super easy to demonstrate in the airplane. Lol.

      King has a decent video on it showing the pylon lagging or leading the wing and altitude adjustments to put it back.

      The important part to remember is that these aren’t “numbers” maneuvers and the teaching emphasis shouldn’t be on memorizing airspeeds, power settings, etc. They are aircraft control demonstrations accomplished by looking out the window.
     
  17. midlifeflyer

    midlifeflyer Touchdown! Greaser!

    Joined:
    May 25, 2006
    Messages:
    10,500
    Location:
    Chapel Hill NC
    Display Name:

    Display name:
    Mark


    1. Just as a point of order, other than picking a reasonable speed, I had none of those things. I had a rough knowledge of the pivotal altitude so you don’t start at some wildly high altitude...

      But it’s a visual maneuver. You can fix everything by just looking out the window.

      You definitely don’t need the wind on any particular shoulder, for example. And nothing I flew the checkrides in had a groundspeed indicator.

      Very difficult to type up how to do this here with one thumb, super easy to demonstrate in the airplane. Lol.

      King has a decent video on it showing the pylon lagging or leading the wing and altitude adjustments to put it back.

      The important part to remember is that these aren’t “numbers” maneuvers and the teaching emphasis shouldn’t be on memorizing airspeeds, power settings, etc. They are aircraft control demonstrations accomplished by looking out the window.
    [/QUOTE]
    Shhh. Better not mention the cheat about the second pylon! :D

    You are correct. The commercial maneuvers are visual maneuvers. We need to understand the theory to understand and anticipate the effects of wind. But then we fly the airplane. We don't fly a theory.

    Back when I was working on my CFI, I overheard an instructor (you'd know him, meteorologist named Nick) do a ground session on turns around a point. He explained the theory in clear, easy to understand language. Then he told the student pretty much what I wrote above. Stuck with me and I found it applied to almost every visual maneuver we did, from crosswind landings to lazy 8s.

    You start an 8s on pylons by selecting a reasonable pivotal altitude based on selected airspeed, wind and theory. Then you bank to it and keep it there. The theory tells you to anticipate the need to change altitudes based on the wind, but your eyes tell you when and how much,
     
    denverpilot likes this.
  18. dtuuri

    dtuuri En-Route

    Joined:
    Apr 21, 2011
    Messages:
    3,824
    Location:
    Madison, OH
    Display Name:

    Display name:
    dtuuri
    Well, you should enter with the 2nd pylon over your RIGHT shoulder. Pick the left one first, then aim to the right of it for choosing the second pylon. You're looking cross-cockpit, so the second one is hardest to select. Don't want to start the maneuver only to roll from the left to the right and find the one you picked out is too close to see. So enter with the second pylon over your right shoulder, IMO.
     
  19. denverpilot

    denverpilot Tied Down

    Joined:
    Nov 8, 2009
    Messages:
    51,216
    Location:
    Denver, CO
    Display Name:

    Display name:
    DenverPilot
    It helps, yes. LOL. But it CAN be done the “wrong” way. Just no reason to purposefully make it harder on yourself. Haha.
     
  20. midlifeflyer

    midlifeflyer Touchdown! Greaser!

    Joined:
    May 25, 2006
    Messages:
    10,500
    Location:
    Chapel Hill NC
    Display Name:

    Display name:
    Mark
    I'll have to try that sometime. I've always started to the right.
     
    denverpilot likes this.
  21. dtuuri

    dtuuri En-Route

    Joined:
    Apr 21, 2011
    Messages:
    3,824
    Location:
    Madison, OH
    Display Name:

    Display name:
    dtuuri
    That's what I'm saying. Pick out the left one first, then enter crosswind down wind toward the second pylon (you're hunting to find a good one off to the right). Start when you have one you can see while level.
     
  22. denverpilot

    denverpilot Tied Down

    Joined:
    Nov 8, 2009
    Messages:
    51,216
    Location:
    Denver, CO
    Display Name:

    Display name:
    DenverPilot
    LOL. I have an instructor who would just chuckle if you did that and call you a masochist.

    “Trying to make it easier for the DPE to see and you have to ask him or her to move so you can?” :)

    Granted he was my primary instructor and not Commercial but I never forgot the mistake or the lesson on setting things up so I had the best visibility for any particular maneuver vs having to look through the bobble head in the right seat. Hahah.
     
  23. RussR

    RussR Cleared for Takeoff

    Joined:
    Jan 12, 2011
    Messages:
    1,353
    Location:
    Oklahoma City, OK
    Display Name:

    Display name:
    Russ
    Mike, I agree with the others. IMO there's no need to be consulting a pivotal altitude table while flying the maneuver. In fact, since the parts with a headwind can easily get down to 600-800 feet AGL, I would say it's not safe to be looking in the cockpit much at all.

    No need to even pick your pylons beforehand.

    1. Have an idea of the pivotal altitude for the start of the maneuver. Let's say it's 1000 AGL.
    2. Put the wind as a quartering tailwind, and fly until you have something that is a good pylon in the appropriate place off your left wing.
    3. Enter the turn, fixing the pylon just above or just below the wingtip. If the pylon moves back, pull back. If it moves forward, push forward.
    4. When you've done 270 degrees of turn, roll out. Fly for 3-5 seconds, then roll right.
    5. Your new pylon is whatever is off your right wingtip.
    6. Repeat step 3.

    I find that pilots agonize over picking the "perfect" pylons beforehand, which of course changes as you move around the practice area. I've seen "picking the pylons" and setting up for them take longer than the actual maneuver.
     
    denverpilot likes this.
  24. midlifeflyer

    midlifeflyer Touchdown! Greaser!

    Joined:
    May 25, 2006
    Messages:
    10,500
    Location:
    Chapel Hill NC
    Display Name:

    Display name:
    Mark
    I can't believe I wrote that backwards. My first pylon has always been to my left. I need to wake up! Vacation does that!
     
    denverpilot likes this.
  25. midlifeflyer

    midlifeflyer Touchdown! Greaser!

    Joined:
    May 25, 2006
    Messages:
    10,500
    Location:
    Chapel Hill NC
    Display Name:

    Display name:
    Mark
    Shhh! I said not to give the second pylon cheat!
     
    denverpilot likes this.
  26. RussR

    RussR Cleared for Takeoff

    Joined:
    Jan 12, 2011
    Messages:
    1,353
    Location:
    Oklahoma City, OK
    Display Name:

    Display name:
    Russ
    Hah! Guess I wasn't aware it was a "cheat"! :)
     
  27. murphey

    murphey Final Approach PoA Supporter

    Joined:
    Aug 21, 2008
    Messages:
    8,940
    Location:
    Colorado
    Display Name:

    Display name:
    murphey
    They looked more like 4's
     
    denverpilot and midlifeflyer like this.
  28. murphey

    murphey Final Approach PoA Supporter

    Joined:
    Aug 21, 2008
    Messages:
    8,940
    Location:
    Colorado
    Display Name:

    Display name:
    murphey
    Good reason to fly a tandem for the commercial.
     
    denverpilot likes this.
  29. iamtheari

    iamtheari Pattern Altitude

    Joined:
    Mar 15, 2016
    Messages:
    1,781
    Display Name:

    Display name:
    Ari
    I need to start shopping for a petite DPE. The Cub doesn't have a great useful load and the Champ is even more restricted. But it would be an absolute blast to fly the checkride in one of them. Other than the pivotal altitude being below 300 AGL if there's a decent wind. :)
     
    denverpilot likes this.
  30. midlifeflyer

    midlifeflyer Touchdown! Greaser!

    Joined:
    May 25, 2006
    Messages:
    10,500
    Location:
    Chapel Hill NC
    Display Name:

    Display name:
    Mark
    I have heard "purists" complain it's not a proper way to do it and the pilot should fail the checkide.
     
    denverpilot likes this.
  31. Ryan F.

    Ryan F. Line Up and Wait

    Joined:
    Dec 23, 2016
    Messages:
    744
    Display Name:

    Display name:
    Ryan Ferguson 1974
    Every single time in my experience. :)
     
    denverpilot likes this.
  32. Ryan F.

    Ryan F. Line Up and Wait

    Joined:
    Dec 23, 2016
    Messages:
    744
    Display Name:

    Display name:
    Ryan Ferguson 1974
    I can't speak to "purists" or "cheats" but Skill element CA.V.E.S3 stipulates that the applicant "selects suitable pylons that will permit straight-and-level flight between the pylons." This is not a nit I would personally pick as an examiner, but it would be fair game in my opinion to require the applicant to select the two points in advance of doing the maneuver rather than "on the fly."

    I realize that one argument against this would be that the applicant could "select a suitable pylon" simply by banking and looking down, and selecting whatever happens to be there. However the Skills for this task are not organized in a fashion which supports this view. Clearly the selection of the pylons themselves -- plural -- is an element into and of itself.
     
  33. dtuuri

    dtuuri En-Route

    Joined:
    Apr 21, 2011
    Messages:
    3,824
    Location:
    Madison, OH
    Display Name:

    Display name:
    dtuuri
    However, you are allowed to make a single turn around a pylon to establish pivotal altitude. At least you could when I was a DPE:

    "CA.V.E.S2 Determine the approximate pivotal altitude."
    So, if you enter like I said before (second pylon over right shoulder), you pick a pylon, establish pivotal altitude and then make the test "entry" all in the first lap.
     
    midlifeflyer likes this.
  34. Ryan F.

    Ryan F. Line Up and Wait

    Joined:
    Dec 23, 2016
    Messages:
    744
    Display Name:

    Display name:
    Ryan Ferguson 1974


    There's no provision for that in the current Commercial Pilot - Airplane ACS, at least not specifically. Determining the approximate pivotal altitude should be done referencing a table, or using the formula. Note this element precedes the selection of the pylons.
    Like I said, it's not a point I'd particularly care to quibble over during a practical test, but in my opinion an evaluator could justify his or her requirement to select the pylons prior to entering the maneuver, if that was their preference.
     
  35. midlifeflyer

    midlifeflyer Touchdown! Greaser!

    Joined:
    May 25, 2006
    Messages:
    10,500
    Location:
    Chapel Hill NC
    Display Name:

    Display name:
    Mark
    You added the words "in advance." They don't appear in the skills.

    But I guess that's what you mean by "Organized in a fashion..." "select" appears at the beginning. So, I guess the pilot doesn't need to "Maintain pylon position using appropriate pivotal altitude, avoiding slips and skids." until the maneuver is over because it's listed at the end? Or maybe you mean not until the second pylon since it's organized after the straight and level portion?
     
  36. Ryan F.

    Ryan F. Line Up and Wait

    Joined:
    Dec 23, 2016
    Messages:
    744
    Display Name:

    Display name:
    Ryan Ferguson 1974
    I figured you'd mention a couple of those points -- they're fair observations. However, it's really up to the evaluator. There's enough meat in the skills to require the applicant demonstrate the "selection of suitable pylons," if that's what the evaluator wants.
     
  37. midlifeflyer

    midlifeflyer Touchdown! Greaser!

    Joined:
    May 25, 2006
    Messages:
    10,500
    Location:
    Chapel Hill NC
    Display Name:

    Display name:
    Mark
    That why I made the comment the way I did. All I said was that some purists would say it was wrong. Apparently you agree.

    BTW, this was one of my CFI checkride tasks. I quite literally described this method when I described "the selection of suitable pylons" and demonstrated it in flight.
     
  38. Ryan F.

    Ryan F. Line Up and Wait

    Joined:
    Dec 23, 2016
    Messages:
    744
    Display Name:

    Display name:
    Ryan Ferguson 1974
    Yes, I simply disagree about the description of "purists." It's a supportable view based on a simple reading of the Task and its Skill elements. I think you make a reasonable argument that the method you described could be acceptable as well. In that sense a purist's passion is not required to arrive at either conclusion.

    You did your CFI checkride many years ago, yes? I wouldn't speak to past iterations of ACS, PTS and FAA Orders.

    Based on the present standards, I imagine some or possibly many evaluators would accept the method you described on a Flight Instructor practical test, but not all of them.
     
  39. Ryan F.

    Ryan F. Line Up and Wait

    Joined:
    Dec 23, 2016
    Messages:
    744
    Display Name:

    Display name:
    Ryan Ferguson 1974
    Also, the AFH doesn't support the "on the fly" method of pylon selection.

    Airplane Flying Handbook (FAA-H-8083-3B) Chapter 6, page 6-16"

    "Selecting proper pylon is an important factor of successfully performing eights-on-pylons. They should be sufficiently prominent so the pilot can view them when completing the turn around one pylon and heading for the next. They should also be adequately spaced to provide time for planning the turns but not spaced so far apart that they cause unnecessary straight-and-level flight between the pylons. The selected pylons should also be at the same elevation, since differences of over few feet necessitate climbing or descending between each turn. The pilot should select two pylons along a line that lies perpendicular to the direction of the wind. The distance between the pylons should allow for the straight-and-level flight segment to last from 3 to 5 seconds."

    "The pilot should estimate the pivotal altitude during preflight planning."

    That's pretty strong support for selecting pylons prior to starting the maneuver. An evaluator who requires selection in this manner has a lot of guidance in his back pocket supporting his request.
     
  40. dtuuri

    dtuuri En-Route

    Joined:
    Apr 21, 2011
    Messages:
    3,824
    Location:
    Madison, OH
    Display Name:

    Display name:
    dtuuri

    According to the AFH (my emphasis):

    "The altitude at which the visual reference line ceases to
    move across the ground is the pivotal altitude. If the airplane
    descends below the pivotal altitude, the pilot should increase
    power to maintain airspeed while regaining altitude to the
    point at which the projected reference line moves neither
    backward nor forward but actually pivots on the pylon. In this
    way, the pilot can determine the pivotal altitude of the airplane.
    "​

    If you're saying there is no longer a one-lap limit then I would say the applicant can orbit around as long as he likes. No tables required.