SP140 hang angle problems

(6) Pitch stability under power. Paramotor Geometry, Part 5 - YouTube

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Moving the soft link behind the clamp helped a lot – it gave me additional latitude in adjusting the hang angle. It might work as a temporary solution. My concerns with this setup arise from having the soft link essentially resting against and putting its full force on the plastic clamp when I’m in the harness. I see two potential problems: 1) wear and tear weakening the soft link from constantly rubbing against the sharp edge of the clamp; and 2) it puts a tremendous amount of force on the plastic clamp – it feels like nearly the entire upward force vector of my weight is pushing against a small plastic clamp held in position by a small screw. If the clamp were to fail in flight (or especially during high-G maneuvers), I think I’d be pretty screwed with a sudden and dramatic shift in my hang angle.

I’m not sure I’m confident enough in this arrangement to actually fly it like this.

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The collar is aluminum with a plastic bushing so it should hold fine but I agree it’s not ideal when they need to be positioned in the more vertical part of the arm. If you plan on doing any high g maneuvers besides wing overs you may want to consider the iris arms or similar because those titanium bars will buckle.

I don’t like the concept of the soft link straddling a collar, specially that far back on the bar. I had access to some bars off a Yooda and I like the soft link connection much better on those. The mounting hole is the same size. I flew with them yesterday and they worked great! Under power I was less than 10 degrees reclined while without power I was close to 15 degrees. I’m 195lbs and use the farthest back position so those arms probably wouldn’t work for you but a similar design with further back positions would be ideal.

Yes those are good videos and I love everything about the Scout except that it’s not electric. However, nothing in those videos explain anything about static vs flight observations and we all agree that too much recline is dangerous. You claimed the static test impacted the results in the video and I disproved that theory with a non static observation. My soft links are directly in line with the thrust and I still get pushed forward. That doesn’t mean the video you shared is wrong but that there is another factor which the video didn’t address. The SP140 has a really low CG which I’m sure plays into it some as well.

Are you able to post a video of the in-flight under-thrust hang angle? I’d be interested in seeing what it looks like.

“You claimed the static test impacted the results in the video and I disproved that theory with a non static observation.”

You haven’t disproven anything! You make a claim to have a video that you haven’t shared for anyone else to see.

About the first thing said above was that yes, the wing will lag to some extent and you will see some of that effect. The point was that you won’t see it to the extent that was shown in the video. Moving to parallel was because the hang points were fixed like a pendulum and the carabiners pivot. That is simple geometry.

Can you show us your video to confirm your “proof”?

And also, the SP 140, with the gooseneck bars are mid-level hang points, i.e., CG is considered to be close to the thrust line. Somewhere in the pilot;s chest say. It is high hang point machines that have low CG, with low hang point machines having high CG.

First one to make video wins lol.

But for real I’m sure the hang test with lines like Braedin show is what flying and throttling up will show. A lot of paramotor designs tilt the pilots forward when they put on power (wing lines get closer to the hoop for the frame) This is wanted over tilting up more, it keeps wing loading on and is more comfortable then tilting back more.

So with thrust angle between wing lines and thrust line will go from parallel to each other or even open to intersecting or closed. So with thrust the angle does flatten out, Ill make a little vid when I get some time. But im sure theres got to be some videos of even other frames showing this effect, just needs to be taken from a selfie stick side view to show well.

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Does anyone know any tips or tricks to get Paul to respond to questions? Do I need to send cookies or something? Like, the questions I posted to start this whole thread?

Three quarters of the battery is below the thrust line and my body from my arm pits down is below the thrust line as well. When I said this motor has a low CG I meant relative to other mid level hang point motors. What you said about the connection point being in line with the thrust is correct but what I said about the CG is also correct.

When you apply thrust the whole motor moves forward while the wing lags back. This changes the AOA of the wing. The motor wants to stay at the same angle relative to the wing because, like you said, the connection points are in line with the thrust. However, now the CG is in front of the hang points instead of below it so it’s the CG that pulls the motor AOA back down. The more thrust you apply the more you swing forward and the more the motor angle change relative to the suspension lines. With the static test the angle change is more which I think was your point and I agree. My point was that the same effect is seen in flight but I didn’t mean to the same degree as the static test. However, the change is still very significant… so much so that I can’t get into my seat on takeoff until I am high enough to ease off the throttle. Which, by the way, is a safer position during takeoff because the motor isn’t tilted back causing potential line twist.

Paul (or was it Zach) has said before that the best way to contact him is through email.
He doesn’t look at these threads that often.

I just thought it was ironic (well, actually, frustrating) that he posted right here in the thread I started about hang angle but seems to have totally ignored the original question that started the thread.

I can’t say that the following suggestion will help, I’m not at that stage yet because I’m new and want to take time kiting with the unit, yet without having battery, prop, hoop, etc. (anything that might get damaged in falls) while getting good with kiting and we’ve too high of winds all week until yesterday.

At 215 lbs. and foot launching with light duty battery my hang problems might tend toward the other extreme.

But anyway, my suggestion is that I noticed in your photo that you don’t have the shoulder straps cinched and tight. This MIGHT be letting the unit hang back further independently of your weight and then you lean back into it. Perhaps cinching the shoulder straps and adjusting them so the unit is high up on your back will make you and the unit act more like a single weight. Just a thought.

Perhaps better is the support straps for front seat board and side do have adjustments.
Have you tried lengthening those straps letting your weight to tilt forward more?
The adjustments are under elactic bands.

In your photo showing landing position it looks like the seat extension flap is folded up. Is it also folded up in the seated photo? This flap could add some leverage where your legs hang and help a little but probably won’t totally fix the problem.

As for the landing position the motor angle changes significantly when you are on the edge of your seat. Here is a side view of an actual landing which looks similar to your hang test and I’ve never landed on my butt. I think the angle in your photo looks normal for landing. Maybe someone has photos of landings with other motors which show otherwise but I don’t think any motor will lean forward much more than that for landing. The forward momentum as you land will help you stand it up.

Do you have a reserve parachute? Where is it mounted? That could help the hang angle too.

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Carful tightening your shoulder straps too tight. It could make it hard to get out of your seat while landing or hard to get into your seat after takeoff. Shoulder strap adjustment is critical when the motor is on your back on the ground but in the air they should not restrain your movement. In the air the motor is NOT hanging from you, it is hanging from the back of the swing arms while you are suspended from the front of the swing arms. The thrust pushes it against your back, the shoulder straps don’t hold it against your back. The shoulder straps have bungees attached to them to take up the slack in flight just so they don’t fall off of your shoulders. In flight the only pressure on your shoulders from the straps should be from the bungees.

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Thank you! This is very helpful. I might have missed one of the seat board adjustments and maybe I need to let it out a bit. I appreciate all the advice!

Thank you so much for the suggestions and advice. I’m still tinkering with all the adjustments, and I probably need to mess around with the seat board a bit more.

The picture of the landing really helps! I also just watched some YouTube videos of people landing, and I think you might be right. Maybe my feet aren’t in as bad a position as I thought.

I think with with tips you all are posting, I’m getting close to having it sorted out. This is my first paramotor, so I’m definitely learning as I go. (I’m a P2 paraglider pilot, but the freeflight harness doesn’t need nearly as much attention with adjustments! :slight_smile: ) You guys have been a huge help!

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Well, for whatever it’s worth, I’ve tried every adjustment I can think of, and the best hang angle I can attain is 17 degrees. Hopefully that’s good enough! Braedin (@glydrfreak) says he’s been flying for over a year at 17 degrees, so I’m going to try it. I mean, at some point I’ve just got to cowboy up and give it a go, right?

Adjusting the front flap of the seat board didn’t change the hang angle at all. That adjustment seems to be primarily for comfort.

Yes, it is for comfort but in one of your pictures it looked like it wasn’t being used at all. Good luck! Fly safe! If anything doesn’t feel right let off the throttle.