Need help with 2 commercial maneuvers

[El Cid Av8or]

In training and preparation for the commercial check ride (should be next week), I have found two maneuvers that I am having a little more trouble mastering than I think I should be having. Those would be the 8's on pylons and steep spirals.

I am flying an early 70s Piper Arrow (200hp with retractable gear) and I am very comfortable with the airplane. My instructor says that I am "well within the standards" for the checkride. I think I need some improvement since I've gotten lucky with these two maneuvers when he has been on board. The other maneuvers have been fine (knockin' on wood here) -- a little extra-fine tweaking over the next few days will be just right.

First, the steep spiral. Glide speed is 105 mph (one more time I wish we had a standard means of measuring speed - in knots!!!) and we have been leaving the gear up and flaps up for the entire maneuver. Power is at idle, prop is full forward, entry altitude is 4000' AGL. Where exactly is the ground reference point supposed to be positioned in relation to the pilot? My instructor says right at the wing root which is pretty much strait down (my head is almost touching the window as I look at it). The problem seems to occur when I turn to the "upwind" sector. Lately we have been having a pretty consistent 15 mph wind which causes me to drift away from the reference point. Also, is there a good way to keep from gaining too much airspeed?

Next, the 8's on pylons. We have figured the pivotal altitude to be about 1100' AGL. No problem. I enter the middle of the 8 heading down wind. Where I get messed up on this one is when the pylon is on the right side of the plane (I'm sitting left seat - my favorite spot on any plane ) and I am turning to the upwind sector. The plane drifts too far over the pylon if I don't bank more than 40 degrees (let's say 50-55 degress which is too much).

I'd appreciate ya'lls help. I'm open to just about anything (except building a 5000' brick wall to stop the wind).

 

[phishn@daves]

Hey El cid, how's it going.

First let me start off by saying that I have not instructed in over two years, nor am I near any of my old training materials. I am only trying to help as I have noticed no one else has replied.

That said; do you have a Flight Training Handbook handy?

I believe the 8's on should be started 45 degrees to the downwind, not straight through the pylons. Also the reason for starting downwind, is that, that will be your steepest bank angle.

I'm not sure why you are banking so much during the upwind portion.

Downwind: the wind is blowing you (ha), further away from your path, hence the steeper bank angle. higher ground speed. slow by climbing.

Upwind: shallower bank. Slower groundspeed, speed up by descending.

Crosswind: you should be able to use the same bank angle at each crosswind point.

did you try looking at the instructor hints section on the main page here. There may be some info there as well?

I hope everything goes well for you, if I get home and get out my notebook I may be able to give you a better answer.

 

[Mr. Irrelevant]

Hey El Cid,


My take on the Steep Spiral is that there will be times, because of the wind velocity that it really isn't a perfect steep spiral. I don't have the PTS in front of me but I recall the only tolerances are airspeed +/- 10 knots and heading +/- 10 degrees. When in the short downwind position essentially I would be banking all the way with a steep bank turning shallow as I roll out with the reference point in front of me, almost on top of it. At that point on the upwind there may be a short period of time where there really won't be much of a bank at all.

I don't know if your instructor is teaching you to be turning at the same bank angle the whole maneuver. Because of the wind I think it would be impossible to fly the manever in that manner. This might be accounting for your drifting....Hope that helps.


Mr. I.

 

[bobbysamd]

Eights-on and Steep Sprials

Alright, I've got Phishin beat; I haven't instructed in ten years, and I had to learn Eights-on after I became a CFI because they weren't required for the Commercial twenty years ago!

I agree with his comments about dropping the wingtip on the pylon on the 45. Drop it right on the pylon at that point. Make sure your sight line to the pylon remains constant. Common errors include selecting poor pylons. Do get a Flight Training Handbook[/]. Do learn how to calculate pivotal altitude so you can (1) explain it for your Commercial ride and (2) teach it for your CFI.

Steep spirals are a ground reference maneuver, but because the bank angle is so steep as compared to something like turns around a point that it won't vary much. Your bank angle will shallow somewhat as you turn upwind. In addition, you might consider trying them with gear down. We did at Riddle in the 182RG. For airspeed control, make sure your airplane is trimmed and do cross check the ASI. I remember being taught this little chant, "inside, outside, point, inside, outside, point." Don't forget to clear your engine.

Something valuable to work on and fun, too, is rolling out of the steep spiral and setting up a crosswind, downwind, base and final to a (simulated) emergency approach and landing.

Hope this helped a little. Good luck with your Commercial.

 

[tarp]

El cid:

Steep spirals: The basic word since when I learned about them 22 years ago is "cheat a little". The picture perfect classic steep spiral is a helix (tornado shape) - you would have to be an artist and perfectionist to scribe the ever-changing (altitude and diameter) of the helix to keep the ground reference point in view. (and PS not on the wing tip like a turn "ON" a point, but just somewhere "off" the wingtip since you are crabbing for the wind).

So to execute this manuever, I used to pick road intersections and my point would be the middle of the intersection. Why? Because you can use the four "spokes" of the crossroads to give you a reference even when you can't see straight down to the intersection itself.

As everyone else has pointed out you must start upwind with your first turn to downwind, this way you can set your 50-55 degree bank and then every other part of the turn is something less than 55 degrees - otherwise you will overbank the airplane and 60.00001 degrees is verboten. Allow yourself enough time for the airplane to gain momentum - for example wind is directly from North or 360 degrees - ergo the fastest groundspeed is just past South i.e. about 10 to 15 degrees of passing south. The airplane has a little bit of momentum.

Every ground ref maneuver should be envisioned with what I call "traffic pattern width" - that is, if you your width from the runway in a standard tight traffic pattern, you are about a mile away from the centerline in most slow-moving general aviation aircraft. You reduce power (ala engine failure) and pull the nose up to glide speed (Arrow = 105mph, 87kts) Trim, trim, trim for the speed. Find your point and bank the turn but easing into the turn until YOU control the steepest bank perfectly at the highest ground speed. There should be no increase in airspeed unless you are pushing against your own trim setting, the airplane should just hold airspeed and with your bank, you take the descent rate as it happens.

Now for the real menace - a lot of DE's do the steep spiral as a surprise maneuver out of high work (watch the top of those chandelle's) and basically pull power, state "engine failure" and then add "why don't you show me a steep spiral on the way down". This kind of messes up all your perfect planning.

The FAA and PTS are looking for airspeed control, bank control, awareness of the ground ref point and wind drift. Outside and inside awareness of altitude, traffic, etc, etc. The steep spiral is basically descending steep turns around a point.

If you get the DE like I had for my commercial, then when this engine out gets pulled, you find the perfect E.O. field and then pick a point abeam the touchdown point on downwind - this is your steep spiral ground ref. As you approach the bottom of your spiral (beautifully timed to be exactly 1100-1500agl) you commence a normal E.O. pattern to the field. Don't forget the gear on final in the Arrow!

Eights On: 105-110 kts maneuvering speed squared divided by 11.3 yields 975 to 1070ft agl. (In mph, divide by 15) So your estimate of 1100ft isn't too bad for a starting point - remember as the ground speed lowers or lessens, you will have to descend lower to catch up to the point. As to ever increasing banks, the biggest problem is that most people start a little too close and are a little too aggressive. You can start with a 45 degree bank at your steepest and downwind point, but this is going to create a very small radius turn. As you come back into the wind (it unmercifully is pushing the airplane into the point even as you are trying to lower the bank angle). Most folks with a good 15-20 kt tailwind and a 45 degree bank start will be lucky to fininish the entire eight without overrunning the last pylon. However, if you shallow out to a 30 degree start, the maneuver is much more gentle and gives you a lot more "wiggle room" with the greater diameter of the circles (egg shapes) that you make around the pylons. Again that mental picture that you are a "pattern width" away from both pylons when you start this manuever will set you up for a much easier time. On the "eights", you can only make the "8" shape to be standing perpendicular to the wind and you will enter the middle of the eight and accept the that the fatest speed will be making that turn from downwind (i.e you start with the wind directly at your back). In later practice, I would "mess my students up" by declaring a road (not aligned in any particular way with the wind) and ask them to perform the manuever using points picked on the road. It really is very easy to do as long as you keep in mind where the wind is and where the fatest and slowest speeds are - now everything is just altitude control.

If your instructor says you are doing good - I would accept that as high praise - sometimes we make more out these maneuvers than we should. I believe the commercial license is about understanding your priorities - safety of flight is number one. So you must show a degree of skill, but this is tempered by your knowledge of where and when to apply the skill - to me, a pilot showing me a perfect steep spiral descending right into power transmission lines didn't get the lesson. Likewise, the omission of clearing turns, head down execution of maneuvers, abrupt control and power changes - these are earmarks of someone just doing the job by rote. Safety, smoothness and self-correction are signs of someone who understands. Use the PTS, try not to read too much into the definitions and enjoy the heck out of this ride - if you passed the oral, you really gotta do something stupid to not get the ticket.

 

[bobbysamd]

Steep spirals and ground ref maneuvers

I used to pick road intersections and my point would be the middle of the intersection. Why? Because you can use the four "spokes" of the crossroads to give you a reference even when you can't see straight down to the intersection itself.

That is exactly how I learned the maneuver and taught it. Great advice. It worked great in Oklahoma because that state is laid out in one-mile sections. There were usually fence lines ½-mile between the roads. Worked great for orientation, and setting up halfway between the roads and fence lines for a quarter-mile radius worked great for ground reference maneuvers, too.

 

[El Cid Av8or]

I would sincerely like to thank everyone for their tips and advice. I read them earlier but was not able to post a reply since I was on a rather slow connection at the airport. Anyway, I finished up the checkride yesterday and the examiner said the maneuvers were done very well. A lot of the tips here were used. The only ones I really could have done better were the soft-field landing (not as soft as it could have been) and the 180 degree circle-to-land (had to do that one twice but nailed it withing 10 feet on the second go-round). Pipers don't land as smooth as Cessnas for some reason, at least not for me. My instructor and the plane's owner both say that they more like "arrive" with a clunk.

So, I'm a commercial certificated pilot now!!! That means that someone can pay me to do what I love to do! That's like getting paid to go fishin'. Oooooooo Raaaahhhhh!!!

Thanks once again. See ya'll in the sky!

 

[bobbysamd]

Congratulations on passing your ride. Without further delay, while you're still hot on the maneuvers, start your CFI.

It's not a matter of Cessnas landing smoother than Pipers. The technique is different. You will "arrive" in an Arrow if you try to land it power-off like a Cessna. In a 172 you can get away with chopping power on short final. You cannot do that in an Arrow. You have to reduce the power slowly to idle in the flare in an Arrow to avoid "arrivals." I know; except for a couple of hours in a 152 the Arrow was the second airplane I flew after 172s.

 

[El Cid Av8or]

CFI training starts Monday afternoon. Now I get to learn to teach the maneuvers from the other side of the plane. I can't wait to get done with the CFI, CFII, and MEI. I've been told by many and I completely understand why it is so that you learn more about flying by instructing than you ever will in traning.

You're right on the power-to-idle cut. I did it too soon and we "arrived" with the clunk instead of greasing in to the runway. We walked away and the gear and rest of the airplane were still intact. Does it still count?