Eights of pylons

Ayork62493

Ayork62493

GBR
Title should read: Eights ON pylons:rolleyes:
I take my CSEL check ride in a week and am comfortable with every thing except one thing... I cannot freaking perform the 8's on pylons. I understand the concepts and why pitch needs to be adjusted but for some reason I can't seem to get them right. I don't know if I'm over correcting or what. The point is very rarely ever where I want it on the wing.

My CFI is a great guy, but the way he's explaining these things doesn't seem to be clicking with me. Am hoping some of you old timers can give me a tip or two to try and get these down so I don't have to cancel the check ride. Maybe how you teach your students? I have searched on here, have read just about all I can find.. Just looking for every thing I can.

Thanks,
Andrew
 
I am not an old timer but I'll try to help. Do you understand what Pivotal Altitude is? It is the altitude for a given ground speed at which the aircraft appears to pivot around. You can find the formula in the airplane flying handbook in order to figure it out.

Basically, pivotal altitude is constantly changing because your ground speed is changing. Pick two points approximately 1 mile a part ( works for a C172) preferably along a road. I think that a road perpendicular to the wind helps with reference. You enter on a 45 degree to the downwind, so figure out what your ground speed will be. (ballpark figure you figure out on the ground before the flight). When the point selected is just forward of your wing tip, turn to "capture" the point and hold it in one position on your wing tip. I like using the nav light deflector mounted on the bottom of the tip. Hold this point during the turns around the points.

As you come around the point, your ground speed will decrease. So, since ground speed is decreasing, pivotal altitude is as well. That means, you need to pitch down, but enough to keep your point right on your wingtip. If there is not a strong wind at altitude, there will not be a lot of altitude to lose. If the point begins to move back from your reference point on the wingtip, then you have descended below pivotal altitude and you need to pitch back up. Be very careful you do not over-pitch. So, rule of thumb is... if the point moves back, pitch up; if the point moves forward, pitch down. Anticipate the descent on the outside of the pylons and the climb on the inside between the two.

Now, as you come back around, you will begin picking up a tailwind. Begin pitching up for the altitude that you started the maneuver at because that is the pivotal altitude for the entry ground speed. You roll out 45 degrees across the road (why I like using a road) and find your next point and repeat the process. Another note, this is a 45 degree ground track, not heading. So if you have a stronger wind, you will need more of a crab angle.

Key points: Pivotal altitude is always changing and you need to climb/descend as necessary. If you find you have to climb when coming around the pylons on the outside, you have entered upwind.

Hope this helps
-
 
A couple of tips I always used are (1) you have to plan this maneuver ahead of time on a day when the wind is blowing more than 10. If you wait to climb or descend based on what you see it's too late and the maneuver isn't smooth. (2) A lot of students adjust their pitch to initiate a climb however they don't realize that by pulling back on the stick they are tightening their turn making the apparent sight picture worse so make sure if you put in a pitch input adjust your bank simultaneously.
 
The biggest thing I usually saw was that students were never looking at the VSI. You shouldnt really be climbing/descending more than a few hundred feet a minute.
 
Its pretty easy - if the pylon goes behind your reference point, apply back pressure. If it goes ahead of your reference point apply forward pressure. This keeps the pylon on your wingtip reference point and is the practical application of all the pivotal altitude stuff.
 
I finally 'got' the maneuver when I imagined I had dual machine guns, one on each wing pointed outward towards the pylons. In a high-wing, I imagine a cross-hairs mounted on the bottom of the wing. My goal is to take out the pylons with the machine guns mounted on the wing. On a stressful check-ride, it was my time to imagine the examiner as being strapped to the pylon...

I also like to make machine gun noises when doing the maneuver.

All the technical talk about pitch up and down when the pylon gets ahead/behind just kind of falls into place when your focus turns to keeping the imaginary cross-hairs pinned on its target.
 
Mine got a lot better when I started anticipating my pivotal altitude change instead of just following the pylons. I always ended chasing them. I still suck at them, but at least I have a better idea what's going on.
 
adk said:
The biggest thing I usually saw was that students were never looking at the VSI. You shouldnt really be climbing/descending more than a few hundred feet a minute.
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Do not look at the VSI. You will mess up the entire maneuver. We normally dim the G1000 down so that you cannot look inside at the display. This is a visual maneuver and not an instrument maneuver.
 
Anticipate the pivotal altitude changes and make your pitch corrections while looking over the nose, not out the side...otherwise you'll overcorrect. Also I think it a little easier if you are closer to your pylons and using a steeper bank.
 
Its all a game of anticipation. I am a couple flight from being signed off for my CSEL ride. I always had issues with chasing the pylons. I started to anticipate what would happen and it all got a hell of a lot easier. Remember than when you try to descend to chase a pylon, it will increase your ground speed so anticipate that you will need to relax pressure and possibly need to level off or start a climb again. The opposite is true for trying to catch a pylon by climbing. I thought of it like that and I stopped over controlling and chasing the pylons because I had at the very least an idea of what was going to happen when "I did this" with the airplane.


On the flip side, Lazy 8's are killing me.....
 
I just went up and did them today, there wasn't all that much wind so it went a little easier, but one thing I noticed was I was overcorrecting a lot... still. Memorize your highest pivotal altitude, and on a calm day the differene between that and your lowest shouldn't be more than about 100 ft. I was overcorrecting and shooting back up to about 100-200 over pivotal altitude and it was killing me, causing me to chase the pylons.
 
I guess the question I would ask is, if this is a manuever required for the checkride, and you aren't proficient at it yet, how/why did your instructor sign you off as ready for the checkride?
 
O&M said:
I guess the question I would ask is, if this is a manuever required for the checkride, and you aren't proficient at it yet, how/why did your instructor sign you off as ready for the checkride?
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I could fake my way through it. Whether I did the maneuver 'confidently' or slogged my way through it and met the proficiency standards are mutually exclusive things.
 
scooter2525 said:
You mean to say you don't do lazy 8s in the jet?
It anything it's learning to fly the plane by tighter tolerances. Anyone can learn to fly strait and level. Well... Almost anyone.
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I don't know how "tight" the tolerances can be for a maneuver containing "approximate" and "visual references" in the PTS judged by a guy sitting in the opposite seat.
 
My advice is to anticipate the pivotal altitude changes, do not focus at all on the instruments, and make small adjustments. It's very easy to blow through pivotal altitude and wind up chasing it.

Also, pick pylons around 1/2 mile apart. This will put you closer to the pylon and require about 40 degrees of bank (in a Cherokee). The maneuver happens more quickly and it's easier to see the maneuver progress, and in my opinion makes it more fun. For setup, fly on a direct downwind to the right point and break off to intercept a 45 degree entry angle.

Calculate entry groundspeed with 1/2 of the current wind speed, you will never have a direct tailwind, only a quartering tailwind. Use the full wind speed to calculate gs flying into the wind, this will give you a good estimate of the variations in altitude needed.
 
I agree with most of the advice offered above. After teaching many students how to conduct Eights On, the key principles to remember are anticipate and smoothness. The purpose of all the commercial maneuvers is smoothness and accuracy. Anticipate the changes in pivotal altitude and begin to make pitch changes before you see the pylon move in reference to the wingtip. If the pylon moves, you're already behind. The smoothness comes in with the climb/descent rates. adk mentioned the VSI, while Eights On are purely a visual maneuver, it may not hurt just to scan the VSI once or twice after you've initiated the climb or descent to see what the rate is. In most scenarios it will be less than 500 fpm. If you can master the anticipation of the pitch changes and limit the vertical rates initially this should prevent chasing/overshooting the proper pitch. It may also be beneficial to attempt the maneuver in some stronger winds (around 20 knots or so). This will magnify the effect and may make the proper inputs more obvious. Once you know what you're looking at, the maneuver will be simple. Have fun with it and keep us informed!
 
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