1. When repairing tears in sailcloth, should you tape the tear on the inside and outside of the wing?

Yes, for field repairs, you want to cut a patch large enough to overlap the damage by at least 3/4-inch. Round off the corners of the patch and apply one inside and one outside, offsetting them slightly to prevent a sharp edge. For small holes (less than the diameter of a pencil), an inside patch may not be necessary, but a smaller patch applied to the inside will keep dirt and debris from sticking to any exposed tape glue. If the damage is on a seam, it should be properly repaired.

2. Is it possible (recommended) to use Duct Tape in the field if necessary? Are there any dangers associated with the adhesive of Duct Tape?

I have seen it and used it, but I do not recommend it at all. I think we have all seen what duct tape looks like after it is exposed to the elements. I am not sure how the glue affects the fabric, but it attracts dirt, it is difficult to remove, and it will make the eventual cloth repair more costly. It is best to have some repair tape in a Ziploc and throw it in the bottom of your harness.

3. Is there any possible method of repairing broken lines in the field?

If you absolutely have to, there is a temporary procedure that can be used on no more than 2 lines per glider. You need to match the material (Aramid/Dyneema) and the diameter to keep the strength characteristics: no parachute cord or clothesline. It is best to obtain a length of main and upper line material for your glider ahead of time and throw it in the Ziploc with the repair tape. Also, any knot will weaken a line, so a good strong knot must be used, like the bowline or figure-eight knot that will retain 85% of the original strength. The length must also match the same line on the other side (within 1 cm).

4. Sometimes it is possible to fly with one or two broken lines. Generally speaking, which lines are these (usually in the upper cascades of the Cs and Ds for instance)?

I would never fly with any completely broken lines. They are all designed to be there for a reason, and any missing lines will affect your glider and put it out of certification.

5. Which lines may absolutely not be broken (As for instance)?

See Above.


6. Although it must be very uncommon, is it ever possible to repair tears in internal ribs in the field?

If it is on a seam, a repair is not possible in the field. Tears usually occur down the middle in the area between the cross port vents because the rib material is usually lighter weight and not subject to abrasion. Tape works quite well on these tears.

7. What might cause a tear to an internal rib?

If you drop your glider on the leading edge, closing off the ports, the weight and momentum can create enough pressure inside to separate the top and bottom surfaces. The damage is not always apparent. On a lot of the rib repairs I do the pilot did not know that it was damaged until another pilot noticed a bulge in the glider. If you “beak” your glider and it makes that characteristic WHOOMP sound, you should check inside for center and V-rib damage.

8. Is it possible to tape coasted Gelvenor? Why not?

Normal repair tape will not adhere to the slick silicone on Gelvenor.

9. How can you repair Gelvenor in the field?

One manufacturer recommends that small repairs can be made by applying silicone glue to a piece of Gelvenor and applying it as you would tape. This works quite well but is not really a field repair as it is messy and takes hours for the glue to set.

10. Are there any other fabrics that cannot be taped?

There are a couple of types of excellent silicone fabrics used in power chute construction in the United States, but I have not seen it in paragliding.

11. What, in your opinion, is the best fabric available for glider construction?

I do not know. I would love to sit down with a group of design engineers and ask them that question. In my opinion, Gelvenor seems to win the durability/longevity contest hands down.

12. Do you repair any and all brands of paragliders?

Yes, my new shop is geared up to handle any type of paragliding service and repair.

13. What would be some clear signs (signs that anyone might recognize upon cursory inspection) of a glider needing to be checked or retired?

It is not always apparent when a glider needs to be inspected. Frayed lines, soft material, and handling problems are obvious, but at that point it is probably overdue. It would be best to send your glider in for inspection on a regular basis (once every two years minimum). I will send it back with a written report that allows you to keep an eye on the wear and tear. As the glider ages we can catch potential problems before they become a crisis.

14. What factors that cannot be recognized by visual inspection would lead to a glider being unsafe to fly (torn or damaged line core, very low porosity, etc.)?

Porosity, Line Strength, and Fabric Strength are all hard to assess accurately without specialized equipment. These are good reasons to have your glider inspected regularly by a professional. Working together, we will keep an eye on these factors as the glider ages to spot potential problems before you end up flying an unsafe glider.

15. How long have you been repairing wings? Is it your main job?

I started gluing patches and sewing lines 15 years ago. It seemed natural as I was the only pilot that had a sewing machine and knew how to use it. In those days, there was not much service available in the United States, so you were on your own. I was able to refine my skills working for Edel USA. I started to think it was something I wanted to specialize in when I was fortunate enough to partner up with Mitch McAleer and learn the fine points. After working in various shops around the country, I decided that the flying community could benefit from a shop dedicated to full time paragliding repair and service.

16. What is the most common glider injury that you see?

Line replacements and torn attachment points are pretty common. Propeller damage seems to be on the rise.

17. What is the most common unrecognized problem that you see in wings that are turned in to you for inspection?

That would be the porosity and strength issues. However, the most common preventable problems are debris inside the wing, which relates directly to porosity and fabric strength; missing line locks, which seem insignificant but your main lines will last much longer with them in place; loose mallions and uneven or maladjusted brake mains; and my favorite – dirty and squeaking pulleys. If a pulley locks up, you can shred your brake main in a hurry!


18. I would like to mention the Harness should also be checked occasionally. Back and side protection can move around. Speed chords can fray inside. Leg straps can wear at the point where they go through or around the seat board. Straps, stitching, and pulleys receive a lot of stress particularly if you are acrobatically inclined.


Matt, thanks for the opportunity to discuss these issues. Hopefully, it shows that pilots can take an active role in increasing the life span of their glider and the overall safety of the sport.

Hey, next time let’s discuss parachutes and repacking for paragliding.

Thanks,
Bill