Jul 28, 2012, 2:00 PM
Post #1 of 6
sweat and gear
How does sweat affect gear??
We have always had a policy that tandem students should wear shirts under their harnesses. Most importantly to keep every Tom, Dick and Harry from sweating in the gear. AFAIK sweat is bad for the gear. Just look at tandem canopies that have been packed by sweaty, no shirt wearing packers. When I approached a Tandem Master to kindly ask him to please put shirts on his customers he told me that it is the students choice whether or not to put a shirt on and that them sweating without a shirt on is just the same as them putting on a shirt and sweating through it.
My stance as a rigger and former TI is that we should try to take care of our gear and part of doing that is to minimize the sweat that gets soaked into it. One sweaty tandem student isn't going to ruin a harness but allowing it to happen more often than not might could shave more than a few jumps off the life of the gear. I have always been taught that sun and sweat are 2 of the biggest deteriorators of gear.
So what does everyone else think? Is sweat as bad for the gear as I have been taught? Do you regularly let your passengers go without shirts?
p.s. - I understand that there are exceptions such as taking a very gorgeous girl on a naked tandem.
Absolutely nothing good can come from it. I'm not sure of all the mecanisems involved but there is a certin amount of salt in sweat and the problems with that are well known. If you land in salt water and fail to wash the salt out of the canopy, pertiularly the lines the salt will crystalize between the fibers of the yarn from which the line is woven. From then on every opening will streatch and saw those crystals back and forth between those fibers. Back when we jumped dacron, a salt water landing with out washing ment you would start poping lines in about 100 jumps.
The lines caring a consetrated load show this most sevearly but I'm sure the same thing is happening in every thing else. Not to mention the corosion on the hard wear. We've seen all of that on pilot rigs, pretiularly sail planes. Harnesses are so over built that they don't break all the time but none of this can be good for it.
Any one want to chime in on other chemical properties of old sweat. I know it has uric acid in it but it also has an organic component the degrades over time. I'm rather cueous what you do wind up with? And how it would effect things.
I'm not sure how much shirts help. Perhaps it keep the sweet on you and lets it dry there like a wick so the crusty salt stains you have by the end of the day stay there on the shirt. Can't hurt.
I'd be more concerned about the packers getting sweat on the canopies than the students stinking up the harnesses. The main reason being that washing the harnesses is easy. Submerge them in clean cold water, let soak, drain and repeat serveral times. The salt and impurities from the sweat will dissolve into the water and be flushed out when you rinse. No disassembly or repacks needed.
Canopies (and rigs) are much harder (or impossible) to wash, and the damage will be harder to avoid. Especially canopies, whose center cells already take a beating during a regular (dry) pack job, get significantly more wear when you bring a shirtless, sweaty packer into the mix.
I will add that letting students jump without shirts doesn't seem like the best idea. It's not all that 'hygenic' if it's hot enough to make a shirtless jump comfortable. You might be able to wash a harness, but not during the day, and those things have to go on other students.
The other thing is that the student has zero protection from abbrasions or other injuries caused by the harness webbing making direct contact with the skin. A hard opening could easliy cause cuts or friction burns to the student if the harness shifts in the just the right direction.
Besides, again, on a day hot enough to make a shirtless jump seem like a good idea, what TI out there is fighting for their students to go shirtless?
(I make all of the above comments assuming we're talking about a male student jumping without a shirt, a female student would be different. If a female student was interested in the same, but also was going to sweat enough to damage a harness, my comments remain valid)