How about just one horizontal roll?
 

I read the three-roll thread and that started me thinking about me trying to keep my one horizontal roll in line when flying Sportsman.

My Monolog-70 tracks straight in rolls with little if any extra input from elevator or rudder. The thing has so much side area it tracks straight very well. (It's not so good in loop maneuvers but that may be because it's a tad heavy for its power).

My EFlite Splendor (which does almost everything else better) is hard to keep straight in rolls.

I've tried to time rudder right, down elevator, rudder left to keep it straight. Do you think that is doing to much and I should just pop a tad of down elevator?

I would think if just elevator was used without rudder, since the down elevator wouldn't exist only during the exact moment of being inverted. I know sometimes when I pop a tad of down elevator into the inverted portion of the roll and leave it in too long, that definitely throws me off track.

-l2t aka Ken

How are vertical rolls?...If they wander to the left or right, you may need to mix in some aileron differential. If it tracks vertical good, maybe try moving the c.g.back a little. How much down elevator are you holding to maintain inverted flight?

I have heard some say no rudder needed but I never saw it that way. Scott McHarg mentioned in his last K Factor article that rudder is needed. One way I have worked it is on the sim go up several hundred feet in "follow behind" view mode and do slow rolls as viewed from behind. I also with the sim set the wind speed to 25 m/s and fly the plane at eye level right in front of my face (normal view) and try to keep the plane in 1 spot as it rolls. Also try flying straight and level with a 1/8th roll - yes you need to blend rudder and elevator to hold straight and level. Seems to me, it's all about the blend.

Scott is a good friend of mine, but I will disagree with him here. There is no reason to use rudder on one roll, especially with today's airplanes. You don't even need it on 3 rolls. The idea of the sequences are to build skills.. In Sportsman, it's supposed to be fun and introduce the box. You also learn basic wind correction and overall presentation. In intermediate, you start doing more inverted and will use more elevator in rolls. There is no reason to use rudder in rolls, until the slow and 4 point in advanced. Too many Sportsman pilots try to fly an FAI "style" in Sportsman rather than working on the true skills it is trying to teach. The sequences are designed to gradually increase difficulty with each new challenge. If you approach it this way, you will see greater results much faster as you are taking lots of small steps, rather than giant leaps. Most importantly though, have fun.

On your splendor, find one of the trim charts that are available and test for differential. I know of one local to me that did some weird stuff and it turned out one aileron had a lot more through than the other at full deflection. Using a throw meter to verify this is also beneficial.

Arch

Archie and all, I'll weigh in. It sounds to me that the guys are wondering about roll rate.

True, for slow rolls, ie- 1 roll takes about 2 1/2-3 seconds, or longer if you extend it, rudder use is required. But for a single roll in Sportsman schedule, 1 roll consumes about 1 second give or take which is a medium-fast speed. What veterans call "normal" speed.

For this roll, rudder isn't really necessary and may actually drive you nuts trying to figure out where you are in the roll and what you're inputing on the tx. As Archie sez, if you find yourself in the latter situation, it will be counterproductive in the short term.

Just so I understand the differential thing. If flying in roll in a vertical downline I get wobble/corkscrew, I want to put in less throw on the down aileron and more on the up?

Here's what I have on the differential thing....

Upwind, 45 up-line, apply full right aileron,
"walking" to the right, decrease downward travel on left aileron
"walking" to the left, decrease upward travel on right aileron
------------------------------------------------------------------------------------------------------------------------------------------------------
Upwind, 45 up-line, apply full left aileron ,
"walking to the left, decrease downward travel on right aileron
"walking to the right, decrease upward travel on left aileron

It helps to use a faster roll rate.
Start with both ailerons moving up and down the same, then the differential won't be so severe.

Agreed, way back in our old pattern guide a slow roll was supposed to take about five seconds and three rolls 5 seconds. If your schedule reckons you can do a single roll as quick as you want then using rudder in a quick roll will cause you more problems than it's worth. However I've seen guys rolling fast lose points because they have trouble finishing up wings level. A noticable "stab" of down elevator in the middle might cost you a point, but finishing up with the wings 30deg out of level (under 1 tenth of a second at 360deg/sec) will cost you more.

Full disclosure, I haven't been at this very long and the past couple of years I haven't flown much due to family commitments. But I have a pretty modern plane, 62" Osiris, but it seems to me that even on 1/2 cuban 8's (much less 1 or 2 horiz. rolls), if I don't use a little rudder on the 1/2 roll the straightness of my line suffers. Yes, I can be accused of being picky. But suchlike pickyness has never been a buzzkill for me, even when I was working on Sportsman sequences, but rather the spice of what makes pattern interesting (for me).

It could also be you are nose heavy. You should be able to do a reasonable rate 1/2 roll on an up line with no rudder. Especially with the size of today's pattern planes. Even on a 4pt roll, you only need to bump the rudder as you get to the point, not constantly flying it as it was years ago. These new pattern planes have nearly as much side area as wing area and as such do not need near as many rudder inputs as years ago.

OK Arch, I'll check it out the next time I'm at the field.