PARAGLIDER LINE FIT

Damaging a paraglider line can be so frustrating when you realize it needs to be replaced before you can safely fly again. And we all know that sending your glider to a service shop can become time consuming and quite costly. Especially when you consider that you will be paying extra for line installation and shipping costs in both directions. Of course, this all can be avoided if you mail order the line and install it yourself. Paraglider line fitting is something that can be done by most pilots given enough time, space, and patience. 

While there are money savings & time advantages to this approach, there are three (3) pitfalls you need to be aware of:

1. THE FIRST PITFAL TO AVOID: 

Make sure you name exactly which individual line segment is damaged or broken. To do this, just review your glider's line plan in its user manual. Often you can download the glider's manual from the manufacturer’s website. These line plans will denote a "line reference code" for every individual line. However, double check your damaged line's placement in relationship to the line plan to be sure you obtained the correct line code. Please keep in mind that line codes may use letters that are case sensitive, numbers & roman numerals. Be exact to obtain your desired lines.
 

2. THE SECOND PITFAL TO AVOID: 

Before you replace the damaged line, make sure the new line's length is fitted, or looped down with an appropriate line loop, to match the damaged line's length you are replacing. To simplify this process, first, secure the risers. Then, secure the new line's end within the riser maillon or soft link (match the existing maillon loop on the damaged line) and pull the lines (side by side) by hand with equal tension (roughly 5 kg or 11 lbs.) to compare their lengths. If you find that the replacement line is slightly longer than the old one (or the corresponding one on the other side) then you should do the same as we would in the workshop and fit or loop the line down appropriately. The extra loops to choose from are pictured in the below section.
 

Note that all lines shrink unless the wing is towed regularly. Usually, the most shrinkage will happen at the beginning of a line’s life span with the process stabilizing thereafter but continuing at a much slower pace. Dyneema lines tend to have noticeable shrinkage during their first 50 hours of use. Aramid (aka Technora, Kevlar) lines tend to start later at about 100 hours of use. However, both line types can shrink more than expected when exposed to water, ocean air, high humidity, extreme temperatures and even more when combining any of these.

Please know paraglider line fitting is not as simple as making the new line the same length as the old one. If we did that, it is reasonable to expect the new line will follow the same pattern as the original line. Meaning, it will shrink the most at the beginning. In turn, which means the new replacement line, within the next 50-100 hrs., will no longer match the existing line set that had already shrunk and stabilized. And, thus, the new line will need to be replaced again. 

To resolve the inherent line shrinkage problem, when the glider has less than 150-hours we make replacement lines at the original factory length, and you can fit the replacement line with a suitable loop at the riser maillon or line-to-line connection to reduce the factory length to match the old line. Pictures of all the loops, to choose from, are in the section below.

And, if your glider has over 150-hours, then, we match the existing line's length & add 5-10mm to it. However, you will need to measure the damaged line or its opposite for us. Here is how to, "Measuring to replace damaged line". 

For mid-lines or upper lines, you should not have to worry about the fit because these shorter lines shrink much less. If by chance there is a significant difference in length, then add an appropriate loop at the line-to-line connection. Lastly, at the next periodic trim tuning of the glider, the added loop(s) can then be re-evaluated and re-adjusted if needed with the rest of the glider. Click on this underlined term, "Adding loops to line-to-line connections" to view a video on it.

There are other types of loops used in this industry than shown, but the ones denoted below are the simplest to make and work on riser maillons (shackles) and at line-to-line connections. Note that the effect of these loops can vary. Examples are tandems, paramotor wings and risers with soft shackles (link lites) where impact of any loop can be up to fifty percent more due to having larger diameter sheathed lines and/or thicker shackles. Whereas smaller diameter unsheathed lines and/or thinner shackles will have a less effect. 

Lastly, if you have a glider using Link Lites (soft shackles) for their line connections to the risers, we have attached Ozone's directions at the bottom for their line removal and replacement.

3. THE THIRD PITFALL TO AVOID: 

After fitting the new line, double check that it is in the correct location and not crossing another row or line inappropriately. That is worth checking right after fitting in the line and again when you inflate your wing next, as part of your pre-flight inspection, just before flying again. Click on this underlined term, "Line Fitting" to view a short video clip on how to eliminate improper line crossings through proper arrangement of your glider, rows, & lines.

Conclusion: Bear in mind that factories specify a tolerance of ±10mm for overall line lengths from maillon to the surface of the wing, but that is primarily intended to allow for variation in lengths that arise in use, and not from manufacturing inaccuracies. For example, when we make a replacement line in the workshop, our standard is within 1mm of specification. However, the factory tolerances show you there is leeway here if the replacement line differs slightly more in length.

CAUTION: Paraglider's line lengths change due to aging and external influences. Thus, we always recommend a trim tuning when replacing 4 or more lines.