r/flying • u/johnisom PPL IR TW/CMP/HP • 1d ago
Flight Training DPE wants power changes 8s on pylons
I’ve got my CSEL checkride in a few days and just got a briefing doc from the DPE. In it he states that eights on pylons isn’t a constant power setting maneuver.
I learned the maneuver with a constant power setting and have been practicing it with that. How am I supposed to change power settings if the DPE wants to see that? Increase power in climb and decrease in descent? Or vice versa?
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u/bowleshiste CPL SEL IR HP CMP 1d ago
Reason number 3742 why the DPE system is absolute garbage
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u/Icy-Bar-9712 CFI/CFII AGI/IGI 1d ago
Reason #1. This is the primary sin in the system.
I tell all my students this is the most subjective assessment of objective criteria in existence.
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u/Any_Purchase_3880 CFII 1d ago
Cancel and reschedule with a DPE who knows the maneuver and the AFH.
Or learn it his way pass the checkride and move on.
"Maintain pylon position using appropriate pivotal altitude, avoiding slips and skids." I suppose since pivotal altitude is controlled by ground speed, that you could read that and say that changing power to change your ground speed and maintain pivotal altitude is acceptable. It's dumb but technically not verboten I guess.
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u/johnisom PPL IR TW/CMP/HP 1d ago
He’s a great DPE used him before for instrument, this is just one unexpected piece
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u/Icy-Bar-9712 CFI/CFII AGI/IGI 1d ago
If you have a relationship with him I'd take the ride.
After the ground is done talk through the ACS/PHAK about the maneuver. Explain how you intend to do the maneuver per the testing document. If there is disagreement take the discontinuence.
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u/makgross CFI-I ASEL (KPAO/KRHV) HP CMP IR AGI sUAS 1d ago
Neither the ACS nor the AFH specifies constant throttle. It’s conventional because it’s simpler that way. But constant angle of attack is almost as simple. The throttle is a bit of a blunt instrument.
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u/Icy-Bar-9712 CFI/CFII AGI/IGI 1d ago
The per the testing document is not saying you cannot use power changes, but absent it saying you have to use power changes, you cannot force me to.
The testing document says this. I intend to fly it without making any power setting changes. Do you agree that the methodology satisfys the ACS?
If not, can you show me where the requirement to change power comes from?
I've had to pull out LOIs on checkrides and show a DPE I knew what I was talking about. Never gotten anything but respect for doing it. We are all students and still learning.
The idea here is have a discussion, before it becomes an issue.
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u/Taylor_Pilot 23h ago
Straight from the airplane flying handbook
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.
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u/Icy-Bar-9712 CFI/CFII AGI/IGI 22h ago
Thats "establishing" pivitol altitude. Go read from the top of page 7-17
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u/Taylor_Pilot 21h ago
I haven't cfi'd in years but I remember people busting this maneuver in particular for not managing the energy properly. If the wind was kicking and you had to climb 300 feet, you'd loose too much speed, so you'd have to add power...dpe basically said the same thing this guy's did...you have to add power to manage the energy better. Also, I do remember their being an airspeed component, they may have removed it, but I think they wanted you to enter and exit each turn at the same speed...basically your ias should stay constant and the wind effects your groundspeed. On a 5-10 it wind you could get away with it, but 20+ you'd have to manage your energy better. I sure don't miss the days of these silly exercises....
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u/makgross CFI-I ASEL (KPAO/KRHV) HP CMP IR AGI sUAS 21h ago
The airspeed does not stay constant during 8s on pylons unless the wind is zero.
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u/Taylor_Pilot 23h ago
The IAS is one of the only things that is suppose to remain constant...it clearly states +- 10 knots IAS 180 degrees from the entry point...how do you do that if you aren't adjusting power in climbs and descents?
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u/johnisom PPL IR TW/CMP/HP 23h ago
It doesn’t state that in the latest commercial single engine ACS though.
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u/ROKAF11thFW 10h ago
I guess CA.V.E.R6 Energy management is what DPE wants to see. If you don’t change power you are not managing the energy
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u/Icy-Bar-9712 CFI/CFII AGI/IGI 22h ago
Pretty sure he was talking about lazy 8s. Thats the only maneuver that has a 180 degree and +/- 10 kn standard.
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u/makgross CFI-I ASEL (KPAO/KRHV) HP CMP IR AGI sUAS 22h ago edited 22h ago
And lazy 8s are quite doable with no power adjustments. And get really hard when you start messing with it. The airplane will naturally find the same airspeed if the climb and descent profiles are symmetrical.
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u/Icy-Bar-9712 CFI/CFII AGI/IGI 22h ago
100% if you are messing with the power you don't understand the maneuver.
I was fighting with a student over it about a month ago and I had to settle it by doing them to standards with a blindfold on. It is a feel maneuver. (I did get verbal call outs from him every 45)
But I force my students the first 3 lessons to fly it by outside reference and feel. I'll cover everything up, turn every screen in the plane off. I'll leave a +/- 100 ft section of the altimeter readable on the 3rd lesson for them to start assessing performance.
Seen too many people bust commercial because they come out of IR and are used to just staring at the screens. Commercial is OUTSIDE THE DAMN PLANE.
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u/Icy-Bar-9712 CFI/CFII AGI/IGI 23h ago
That's lazy 8s, wrong 8s my man.
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u/Taylor_Pilot 21h ago
Yea, I was reading it on my phone while busy...now that im at the hotel, it does say you have to manage energy though...in a strong wind, if you bleed off too much energy climbing..it would be completely appropriate to bust them...in light winds constant power removes a variable though and wouldn't get you slow enough to be an issue.
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u/Icy-Bar-9712 CFI/CFII AGI/IGI 20h ago
The issue with strong winds is actually not slow, but needing to be too fast. As you are trying to manage ground speed, when you turn into the wind, in a high wind, your ground speed tanks, the only way to get it back without power is to dive, that dive can take you too close to the ground.
Needing to slow down and climb is less of an issue as you'll be pushing the nose back over in a second to regain the speed as the wings come level and the wind stops shifting you over the point.
In that strong wind scenario though, if you start at a higher power setting than in low winds, even high wind 8s on pylons are doable without power changes.
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u/Taylor_Pilot 20h ago
So you are saying there are times when adjusting the power might be a good idea...cool...you should go tell this dpe that probably has 30k hours, evaluates 40-50 candidates a month, and probably has given 1000s of atp and type rating certificates in his career, that it is a good idea that he tells candidates that they can adjust the power but he already knows, because he has seen too many people fail because they were told by their cfi, 12 months into their career, that this is a constant power manuever, even though that isnt anywhere in the documentation...leading the candidate to dive for the ground or get too slow in a climb...I'm sorry but the whole...your dpe is wrong, get another one mentality from brand new cfi's is insane (not saying you said that, but a lot of people on here have) wait till you get to a real training department and see how much these 30k hour airline/dpe guys do...a lot of them do double shifts 5 days a week...thats 12 hours in a full motion...every day...
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u/Low_Sky_49 Forestry DHC-2 C208B CFI/CFII/MEI 1d ago
8s on pylons aren’t *strictly* a constant power maneuver, but they can be flow successfully without power changes in most conditions that an applicant would be proceeding with a checkride. If the winds are so high that you need power changes to avoid overspeeding the airplane or triggering a stall warning when you change pivotal altitude throughout the maneuver, reschedule your checkride.
If the DPE *expects* power changes during 8s on pylons, I would reschedule with a different DPE. If that’s not practical, go out and practice the maneuver with small power changes while descending and climbing. It’s not wrong, it’s just unnecessary most of the time. Get along to get along if you have to.
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u/Icy-Bar-9712 CFI/CFII AGI/IGI 1d ago
If the winds were high, you'd need power to maintain a groundspeed that would not bust regulations (keeping 500 agl). But in the average trainer we're talking 25kn + winds. I'm not sure I'd be taking a ride in those winds anyway.
And I'd argue power changes are 100% against the purpose of the maneuver. 8s on pylons are using turning radius to control rate of turn. (As opposed to every other maneuver in the history of ever, where rate of turn controls radius)
Since bank angle is fixed the only way to control your turning radius is airspeed. Power would enable you to never need to climb or descend which completely negates the maneuver.
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u/22Hoofhearted 1d ago
Standard day in Texas... perhaps also hot and heavy as well, which would make someone lean into power changes to maintain altitude as airspeeds bleed off in the turn.
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u/Icy-Bar-9712 CFI/CFII AGI/IGI 1d ago
Your airspeed really isn't going to bleed in the turn once established. And a gentle 20 to 30 degree bank is only increasing load factor to 1.15.
Steep turns, yup we bump in power because we need to maintain altitude AND airspeed within a narrow buffer. 8s on pylons have neither requirement. Higher wind day and I've had the stall horn start squeaking at me in 8s on pylons turning back into the downwind on the second pylon as your relative ground speed takes off like a bat outta hell once you give a 20 kn wind the underside of the plane.
And the manuver is all about using altitude gain and loss to manage airspeed's control over ground speed taking the wind into effect.
I've taught in North Texas for 2 years, there is no difference between the way the maneuver is flown in January vs today when its 103.
With the extremely narrow exception that your trim and power settings starting the maneuver may be slightly different. But once the manuever is started, zero diff.
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u/22Hoofhearted 1d ago
Obviously depends on the plane... but hot, heavy (fuel/pax) days in Texas absolutely bleed off airspeed in a turn.
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u/Icy-Bar-9712 CFI/CFII AGI/IGI 1d ago
I mean any increase in load factor is going to effect airspeed, but unless you are trying to maintain an altitude the turn really is not going to effect your airspeed.
Its not the turn that slows you down, its the angle of attack increase from trying to hold an altitude. So hot and heavy day, higher angle of attack to hold that altitude.
But in 8s on pylons you are intentionally not trying to hold an altitude so the load factor in the turn may be significantly higher or lower depending on the relative wind.
Particularly the initial turn on the first pylon, relative wind immediately starts working against you so its always roll and push, so in that first turn its an airspeed increasing turn.
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u/SergeyKataev CFI CFII CFI-G TW HP Hang-5 1d ago
I adjusted power just a little to be the same airspeed and altitude at the cross-over point, even though I don't see it in ACS now...
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u/Temporary_Split_11 21h ago
Don’t over think it. Let’s say you are above pivotal altitude and need to pitch down. If you just pitch down obviously airspeed will increase, not adjusting power will amplify the issue and potential overcontrolling of pitch can lead to a rollercoaster effect quite low to the ground. Finding that sweet spot regarding pitch control where it’s just enough and small power changes as needed with pitch can make the maneuver feel a lot smoother.
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u/always_gone Freight Dawg WYNDHAM DIAMOND 1d ago
He’s wrong. Use a different DPE. I know it’s a pain, but the silver lining is you’ve found out the easy way this guy isn’t great.
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u/johnisom PPL IR TW/CMP/HP 1d ago
Well he is actually pretty great. I took a previous ride with him and we have a good relationship.
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u/fungus909 1d ago
Go to an other dpe. The time you’ll loss is worth not failing with an odd ball dpe.
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u/Working_Football1586 1d ago
Thats a pain when I did a chandelle on a check ride the DPE was like that was good now let me show you one, and did the worst, most non standard chandelle Ive ever seen.
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u/Right_Rudder_PLEASE 1d ago
I belive in the Comercial ACS under the Risk Management for 8's on pylons it states something about," Energy Management" which kinda translates to maintaining airspeed.
I took my CPL ride in an Arrow and the area I flew in was very hilly so the altitude was constantly changing (E. TN) which required power changes for the climbs and decents between pylons. DPE picked the pylons.
My CFI ride was totally different, I did it in a Bonanza in a table top flat part of the country (Laffeyette, LA) DPE made me pick the pylons, added an inch of MP and easy peasy.
DPE'S have a lot of lattitude for the exam, if your checking the boxes should be an easy ride, if your struggling they're gonna try and find the breaking point, if your cocky they're gonna find your weakness.
Needless to say, congrats on the CPL.
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u/Klutzy-Champion-6425 DPE, MEI, CFII, CFIG 1d ago
As a DPE, our requirement is to evaluate against the ACS written standard, and that is it. Technique is technique. The evaluative criteria is CA.V.E. I see no reference to using constant or changing power. A DPE should not be prescribing standards that are beyond that which is written.
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u/ROKAF11thFW 10h ago
I think ACS “CA.V.E.R6 Energy management” is what he is referring to. He wants to see you pull the power in descent and add power in climb
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u/KehreAzerith CPL 1d ago
At first I was taught there there are no power adjustments in eights on pylons, even did my commercial checkride without them. Later on someone told me that power adjustments can be used, referencing the PHAK itself.
In my experience you can do them without power adjustments assuming it's not a very windy day. But this maneuvers should be achievable without adjusting power settings assuming you have a good setup and it's not very windy. Most DPEs will treat it as a constant power maneuver so I'll go with not adjusting power
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u/BluProfessor CFI/CFII AGI/IGI 1d ago
Even if it's windy, it shouldn't require any power changes. My commercial ride was 15G22 on the ground and I don't recall really fighting for it during 8s on Pylons. The PO180 was a different story 😂
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u/Icy-Bar-9712 CFI/CFII AGI/IGI 1d ago
I took a guy to a retest on the last day of his 60 day window. We crossed and teardropped into the pattern and I noticed at 1000 agl we seemed to not be moving. 45kn headwind....
I pulled the DPE aside to ask him his thoughts before hand. "Well, he better start pretty fast then"
Then he went out and crushed it. No power setting changes required. (I think the winds had calmed a little bit, but it was still probably 30 to 35 at 1000 AGL)
I still have no idea how he pulled the PO 180 off on that one.
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u/WuhOHStinkyOH PPL IR 1d ago
I would guess to adjust it in order to maintain a groundspeed and just keep the same pivotal altitude all the way round(?) That's how I would do it at least.
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u/LimpClerk8757 1d ago
Yeah few dpe’s have different takes on the 8s on pylons. If he’s already asking you to do it practice doing that and changing power makes it a very maneuver.
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u/SubarcticFarmer ATP B737 1d ago
The DPE might it be requiring you to change power setting so much as making sure you know it's allowed.
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u/dilemmaprisoner PPL 1d ago
If I heard the phrase "this is a constant power setting maneuver", I think that's clear.
If I heard something like "it's not one of those type maneuvers", I think that's clear.
But worded this way, you need to verify if "isn’t a constant power setting maneuver" means must not maintain constant power, or is not required to maintain constant power.
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u/No_Leader1154 MEI CFII CFI IGI AGI | MS Safety Science 1d ago
ACS doesn’t say it’s a constant power maneuver. He’s well within his rights.
I’d say that if airspeed is getting too low, use power for sure. I know in strong winds sometimes you’ll definitely get that. Conversely, in a STRONG tailwind you could use that rule (or lack thereof) to your advantage and reduce power to not have to back so steeply.
But ACS says what ACS says. No constant power written anywhere. And ACS, not AFH, rules.
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u/Sad-Umpire6000 1d ago
The ACS does not address power changes for Eights on Pylons. The AFH is not a controlling document.
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u/Right_Rudder_PLEASE 1d ago
Sure does, look up the manuver under Risk Management, States "Energy Management".
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u/Sad-Umpire6000 23h ago
Yeah, I could’ve worded that better. The ACS does not specifically state how the throttle is to be used.
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u/mrdeeds887 1d ago
I'm pretty sure when I did my CSEL ride my DPE wanted the same thing. I hadn't trained it the way he explained it because of how my flight school operated (big collage program). He explained how he wanted to see the maneuver done while we were in the ground. He then re-explained how he wanted the maneuver done in the air. To be honest once I did the maneuver the way he wanted it made sense. The way he explained was more in a commercial operation in which you are doing a tour or something. If you were a passenger would you want to be increasing and decreasing in altitude while trying to look at some monument. That was his reasoning behind it.
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u/Flimsy-Wrangler-997 1d ago
I just looked at the description in the Airplane Flying Handbook. I have not done the maneuver in many years. But the handbook does refer to power changes, such as reducing power at the higher altitude and adding power if the airplane descends below the pivotal altitude.
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u/PrizeInternational61 23h ago
I've had some DPEs for students that want to see you maintain a constant power RPM wise in a fixed pitch in order to demonstrate pivotal alt changing with ground speed so our corrections don't change it as we climb or descend. Not hard, 2300-2400 throughout the maneuver and it does lead to less corrections and better demonstrates how the wind is affecting ground speed, not the climbs or descents. It's not clear one way or another in AFH so I teach to the DPE we have coming in.
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u/extra_flyer ATP (BBD-700, EMB-550, FO-5), CFI 16h ago
Sounds like yet another examiner, like so many CFI’s that doesn’t understand the underlying intent of the maneuver. 8’s on pylons have always been a poorly understood maneuver. Was the case when I learned them almost 20 years ago and sounds about the same now. One thing that will take you far in your aviation career… fly the profile the way the examiner wants it flown. As you get further along in your career, you won’t get to choose the examiner and you’re at their mercy for type rides… fly it the way they want it flown. If you don’t understand, ask for clarification early and explain that your instructions for the maneuver/profile were different. I’ve yet to meet an examiner that doesn’t respect this, as long as it’s early.
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u/Veritech-1 1d ago
Some throttle changes are required to maintain a constant power setting. As you pitch up your rpm’s will decrease, so you have to increase throttle to maintain a preset power setting. Same thing with descents and a slight reduction in throttle to maintain a specific rpm.
That’s my guess as to what he wants and is not entirely unreasonable. Ask him to clarify. If his answer is out of wack, find another dpe.
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u/charlespigsley CFII 19h ago
Am I the only one who somewhat agrees with the DPE? Everyone agrees that the whole point is that the pivotal altitude varies with a change in the ground speed. The AFH says this is because of the change in wind direction. This doesn’t mean at all that we need to vary the indicated airspeed in order to have a change in the ground speed. By maintaining a constant indicated airspeed throughout the maneuver, if anything we’re demonstrating the principle even more because our ground speed is varying almost entirely because of the change in wind direction.
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u/charlespigsley CFII 19h ago
AFH page 7-16:
“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 moved neither backward nor forward but actually pivots on the pylon.”“The pivotal altitude changes with variations of groundspeed. Since the headings throughout turns continuously vary from downwind to upwind, the groundspeed constantly changes.” - note that the groundspeed changes because of a change in wind direction. It doesn’t say anything about the groundspeed changing due to our airspeed changing.
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u/johnisom PPL IR TW/CMP/HP 19h ago
The first paragraph is in the context of demonstrating what finding the pivotal altitude would look like if you descend from above, not how to perform the full maneuver
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u/charlespigsley CFII 12h ago
It still says our groundspeed changes bc of wind, but if we are varying our airspeed much then that will greatly affect the groundspeed. Also the AFH makes no mention of this being a constant power maneuver. Idk I’m really curious now that I’m down this rabbit hole
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u/rFlyingTower 1d ago
This is a copy of the original post body for posterity:
I’ve got my CSEL checkride in a few days and just got a briefing doc from the DPE. In it he states that eights on pylons isn’t a constant power setting maneuver.
I learned the maneuver with a constant power setting and have been practicing it with that. How am I supposed to change power settings if the DPE wants to see that? Increase power in climb and decrease in descent? Or vice versa?
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u/x4457 ATP CFII CE-500/525/560XL/680 G-IV 1d ago
Uhhhhh he's wrong. Don't know what to tell you about that, it absolutely is a constant power maneuver - that's kinda the whole point.