MISCELLANEOUS STUFF

RISER BAG: This small zipper-sided bag made of scrap cordura really helps to keep tangles out of the lines. Simply clipping the risers to the side of the wing bag, always seemed to result in tangles, and there was always a few minutes time wasted sorting out lines before flying or kiting practice. This hasn't been a problem since I started bagging the risers.

A while ago I read a tip on Biglist a tip to pull a handful of wing material trough the middle of the coil of lines you made as you put the lines into the rosette bag. This is a good way of ensuring the coil comes out as neat as when you put it into the bag, and without twists.

GAS CAN CARRIER: To keep the gas smell out of my car when I’m driving, I keep one-gallon gas cans in a Coleman cooler. The cans are available through Walmart Canada, with both US and Imperial gallon markings, and which I also marked for my own purposes at the 4-litre level. The Cooler is a Coleman Poly lite 24" x 18 x 18 inches.

BATTERY SCREWDRIVER: This lightweight, rechargable, lithium-battery screwdriver is frequently on sale for half price at Canadian Tire. A hex speed change bit to fit the hex bolts on my prop bolts, only cost a couple of bucks. I keep a 5 mm bit for the Simo, and an 8mm for the Black Devil. It makes putting on and taking off the prop the work of seconds instead of minutes. That’s an extra couple of minutes to fly, and a couple of minutes shaved off the breakdown before going home.

LUGGAGE TAG:  Anytime I'm traveling, or when I’m flying somewhere whether alone or not, I carry a small luggage tag with my medical/contact info in the event of a worst case scenario, including my blood type, medical allergies, health insurance info, and emergency contacts.

A print shop, or Staples Business Depot, will laminate a homemade, business card-sized tag for you for a little over a dollar.

LIGHTMAN STROBE: I bought my Lightman strobe from Bruce Brown at Flyohio.com

It's a small, but powerful unit, at under 30 bucks. Its 1.5 Km range, means it's shy of the 3Km necessary for FAA compliancy as an aviation strobe, but I like flying with it when I'm at unmonitored airports with small planes buzzing around every once in a while.

I feel better knowing that I'm a little more noticeable.

I don't fly with the strobe, all the time, but when I don't, the 14/20 tripod screw on the "belt-mount" does double duty as a base for my wind speed indicator, till I'm ready to go up.

PROP BOLTS:  Speaking of prop bolts, (I'm sure somebody, somewhere, was speaking of prop bolts), I keep a couple of spares handy, in case I ever drop one in the tall grass when I'm getting ready to fly. Buy extra bolts BEFORE you need them.

ON KEEPING WARM: Gloves: One tip for keeping your hands warm is keeping your core warmer. An extra layer on your chest will cause your body to release more heat to your extremities.

Wearing a helmet-liner on really cold days will reduce heat loss from your head as well.

Tape chemical handwarmers to the inside of your wrist, not the back of the hand. This is where the veins are closest to the skin's surface, and where the blood is travelling into the hand. The back of the wrist is where the blood exits. "Most glove/handwarmer pouch (manufacturers) got it backwards.”
Hat tip to Jim Doyle, PPGBiglist.

PROPELLER BAG: Hard sided, polyester rifle cases are inexpensive ways to protect your props while traveling.

Below is a picture of a ski bag that I cut down and use to carry a prop and a spare. I cut the ends off, and excised about a foot of material off of each end, and re-sewed the ends back on.

I sewed some stretchy nylon onto some lengths of foam to keep the props centered, and protected from dings.

I like to keep an extra prop on hand, because, as someone said, “One sure way to ensure that you’ll never break a prop is to buy a spare before you need it."

SAFETY KNEE PADS:  Knees can take a beating on both launching and landing. The multiple deep grooves and scratches on this pair would otherwise have been grooved into my legs. I really recommend knee pads.

I’ve tried a few different brands, RollerBlade, Aerosport, to name a few, and like these made by Bauer for both comfort and stability. A lot of other pads slip, and slide down the leg. For some reason, these don't so much, and I pretty much forget about them once I put them on.

TRACTION AIDS

Morning flights in summer time offer safe, calm, non-thermally air, peace and quiet, and the beauty of the sunrise. But summer morning also means dew on the ground, and fresh dew can make for slippery take offs, and dangerous, slidey landings. These Yaktraks are designed for walking on icy surfaces but are also great, light-weight, traction-aids on wet grass. (The case is just an old, soft-sided CD carrying case with the inserts torn out.  The inserts are usually a mess by the time I take them off, and the case, keeps the mess contained till I can hose them off.)

Many ice-traction options are available, and you might check out ebay for some comparison shopping, but out of all the ones I've looked at, these Yak Traks, are a best-buy.

Robust, yet light. Secure, but easy to take on, take off, and clean.

STUFF I CARRY IN THE CARGO POCKETS OF MY MOTOR: First Aid Pocket - A tiny bottle of DEET bug juice. A tiny bottle of sun screen. A tiny ziplock bag with alcohol wipes and a couple of boo-boo bandages for little cuts, and Nitrile gloves, a 4x4 gauze pad, and a small 25 Gram packet of Quick Clot for, (let's hope not) really big ones.

First Aid for the motor - A few zip ties. Some gaffer (photographer's) tape. It's like duct tape, but leaves no residue. A mini multi tool. A spare hex-wrench for the prop.

I don't fly with it, but I also have a Altoids tin with a spare line, and some wing patch material close at hand.  Elizabeth at Paratour, can set you up with a nice mini-repair kit including line and tape, even a pair of scissors, for $25.00.

DROP LEG BAG

PPG’s don’t lend themselves well to carrying stuff. Your back is carrying the motor, and attachment straps are covering all but a small area of your chest. However, your legs are easily reached from the sitting position, and your thighs and calves can be used to load gear, keeping it accessable while flying but out of the way when launching.

I use a drop leg bag to carry a camera, and some other gear on my thigh. The same carrier that I modified to make a chest rig. Any thing I want to carry aloft, I adapt to fit the MOLLE pattern and weave on the pouches/carriers that I specifically need.

By the way, Military leg pouches often have two straps going around the thigh, and two straps help the bag stay where you want it.

A simple drop leg carrier can be made out of 2” webbing, a buckle, and some Velcro. Any bag design you choose can be thus attached. This bag is a MEC (Mountain Equipment Co-op) satchel, that I modified with a drop leg attachment, and a thigh strap.

LINKS

Here are some free links to online PPG training in no particular order.

ONLINE INSTRUCTION: Books and Pamphlets
http://www.faa.gov/library/manuals/aircraft/media/FAA-H-8083-29.pdf
This is a very comprehinsive online book put out by the FAA on Powered Parachutes, including information on: weather, wing dynamics, air space, etc. PP but very applicable to foot launch PPG.

http://guitarz.org/ppg/paramotor_tutorial.html
A Basic Instructional Primer For Beginning PPG/Paraglider Pilots.

http://footflyer.com/PPGBibleUpdates/index.htm
The source for PPG pilots. Online instruction, and other links from USPPGA and Jeff Goin

http://www.paragliding-tales-and-reviews.com/paragliders-2009.html

Info on gliders, but also an instructional page.

http://www.paragliding.com/?q=node/58

Late PPG pioneer Pilot Dixon White's page. Lots of great essays, and instructional advice.

http://www.auf.asn.au/meteorology/index.html
Weather and meteorology for aviation. Good info on wind and turbulence factors in micrometerology section. Site is designed for aircraft and PPC pilots, but you can spend hours following links with information applicaple to PPG

http://skyvector.com/
Flight planning and aeronautical charts.


ONLINE INSTRUCTION: Video
http://www.olympicppg.com/PPG/articles.html
Video PPG training tips by pilot Tom Scott


USEFUL LINKS

http://www.airkingpropellers.com/
Air King Propellers LLC
Inexpensive, but high quality props for PPG.  Wood, Kevlar adn composite. Fast cheap shipping from the UK


http://www.poweredparaglidingcolorado.com/Resources/Resources.html
Very comprehensive list of PPG links
windtracker systems

http://www.emc.ncep.noaa.gov/mmb/nammeteograms/

WEATHER

http://localkitespots.com/vmap.aspx?site=1246632867876
Michael recommended this. Designed for kiteboarding, but wind is wind

Garmin RINO case

My radio is a Garmin Rino 536. Because it is also a GPS, Altimeter, and digital compass, I wanted a deck style platform so I could read the screen while flying. I made this cordura case, which is MOLLE compatible, so I can wear it on my chest rig.













This case has a full Cordura cover, but all that is required is the basic structural shap, with the drop down deck flap. It is just Cordura material, contact cemented onto some heavy plastic. One side is padded with a little microfiber covered foam. A slot is cut inot the plastic, and the drop cords are just lacing material on speed lace D-rings.

recycled the Cordura, the plastic material, and the foam to make this, from a salvaged 3-ring binder zipper closing binder. I played around with the basic design even developing a zipper case for the drop platform. Its handy to have the radio close to my body when launching, but horizontal to access the GPS, maps, compass and altimeter.

A similar drop-down system could be rigged for any GPS or radio/GPS combination.

SIMPLIFIED VERSION

I made this for may companion radio a Rino 130. Tehre is no over case, which better shows the simple drop-down concept.

The framework is made of two pieces of 6 1/4" plastic 2 1/2" wide, and a base 2" x 212" wide.

They were laid out in a line, and contact cemented to a long piece of Cordura. I left an 1/8" space between each section to allow for a fold/crease when the case is in an open-sided box shape.

I drilled two holes, to make a slot for teh Garmin belt clip, and attached two short lines of para-cord to make the "draw bridge" lines.

I also riveted two L-brackets on the face piece to add a little extra structural support.

The paracord is secured with shrink tubing, over the type of D-ring connectors used on boots. They are riveted through the plastic.

This is the front view. The case stays closed in the vertical position for take-offs adn landing. Then a single nylon connector lets the radio drop down to horizontal during flight. Here is a rear view showing two Molle straps, which are made of the same plastic, which I covered with Cordura with contact cement. A little extra Cordura made a folding tab which I cemented and secured with two rivetss per tab strap.

MOLLE Chest Harness

My chest platform/radio harness is designed with a military MOLLE (MOdular Lightweight Load-carrying Equipment) system used by police and armed forces world wide. The platform is a grid work of webbing straps (PALS) onto which you can weave the attachment straps of compatible pouches and accessories.

The platform is use is simply a modified drop leg thigh rig I picked up on ebay for five bucks from a seller called "Tactical Gear Store." The listing title “USMC US Army Airsoft Molle Drop Leg Panel Platform” and cost $5.95 plus $5.00 shipping in 2010.

I cut off the drop leg connection, (the short vertical strap at the top as seen above, that normally connects the panel to the wearer's belt) and sewed on a strap to go around my neck instead. I used two 1” nylon quick connect buckles and a 16 inch piece of 1” webbing.

Then I removed the two horizontal thigh straps and substituted a single, long, adjustable belt which wraps around my torso.

The beauty of the Molle system, (pronounced molly) is that a wide range of components can be quickly added or removed as required, but remain very securely attached.

Smoke Wind Indicators

My absolute favorite wind indicator of all the choices out there, when wind is so slight as to be practically nonexistent, are these tiny, inexpensive, smoke bombs. These little guys are available in pretty much every roadside fireworks emporium in every State.

You simply light the fuse, and toss one in front of you, and they’ll indicate even the lightest breeze, which is a big help for virtually nil-wind launches. They give off a streamer of variously coloured smoke that lasts about 10 seconds. Then, if picking up the shell later on isn't practical, being made of cardboard and clay, they'll just biodegrade.

I cut an inch of excess cardboard off the bottom of the things to reduce their length so that they will fit neatly in a dollar-store AA battery case. Then I spot glued a pair of wooden, strike-anywhere matches to the side of each one, along with a bit of sandpaper/match-striking material as well. (My experience with strike anywhere matches, is that they strike almost NOWHERE effectively, except on the sandpaper striking surface on the side of the box that they came in.)

These pull-pin smoke grenades, are harder to find, (try ebay) but score very high in terms of fun factor. They don’t require matches to ignite, so I carry one in the air with me, to drop on a potential LZ if other wind indicators are not readily apparent. These grenades smoke for about thirty seconds, which should give a pilot enough time to orient a landing.
I've twice had to land some distance from my planned LZ, and both times I had no clue as to the wind direction. Fortunately, the wind was light, and I was able to safely run out my landings, but had I guessed wrong, or had they been days with significantly higher winds, coming in downwind might have led to a serious mishap.
These smokers come pre-wrapped in cellophane, but for ease of use in the air, I keep one pre-unwrapped, and with its pull-pin taped to the plastic with fabric gaffer's (similar to duct tape), so its ready to go.
I saw them here recently online for $4.95:
http://www.onlinefireworks.com/smokegrenades.aspx

I find that they fit nicely in a Y2K era cell phone case that I keep clipped to my motor harness so it's always handy, and it will be handy if I ever need it.

Or try a Military surplus Flashbang pouch like this one, $4.95 from eBay seller Defence Acquisitions.

'Kaboom Fireworks' stores in Toronto have recently reduced the price on these pull-pin (no match necessary) grenades, marked down to $11.95. Like most fireworks, smoke bombs are more expensive in Canada than in the US, but at least people in Ontario can get a hold of a pull-pin smoker for a fairly low cost, and from a local source. These guys kick out smoke for a full 180 seconds, but are about the same size as the plastic pineapple encased ones above.

Mini-telescoping wind pole

My Youtube video link here:

http://www.youtube.com/user/whiteknight38cdn?feature=mhum#p/a/u/0/MSM-8Eg4H9U

My Mini-pole, is made from a telescoping, magnetic-tipped reacher (used as a long-reach magnet for picking up small ferrous objects) that I picked up for a dollar at the dollar store.

The reacher is about the size of a pen, so it fits handily in a pocket, yet has an extended length of about about twenty-four inches. I cut the magnet off, and JB Welded a number-four fishing swivel in its place to attach a bit of streamer, or a mini-wind sock.

I cut the pen-clip off, and jammed on a bit of tubing, (I used scrap ¼” fuel line) I can slip it on a cut off tent peg, to ground mount, or slip it over the radio antennae of a car.

Weebles wobble...

My Youtube video link HOWTO here:

http://www.youtube.com/user/whiteknight38cdn?feature=mhum#p/a/u/0/MSM-8Eg4H9U

Here is one of my Weeble Wind Indicators. It’s made out of the toy surprise container from a chocolate Kinder Egg. The old style two-piece orange Kinder eggs work okay, but the new yellow style has a hinge, and is my preferred choice.

Poke a hole in the top, and JB Weld on a fishing swivel. A number 4 works nicely, but pretty much any size would probably work. The first ones I made I used a bit of para-line cord to attach my streamer to the swivel. Then I found an even better solution: a fishing "leader", a short 3-inch bit of wire line, with a swivel at both ends. (Available for a couple of bucks at Walmart)
Attach a bit of ribbon. to use as a streamer. I used some orange, plastic line marking tape. A piece about three feet long. Fold and glue one end to stiffen the material, or set a tiny grommet.

Now weight the wobble base with a rare earth magnet. You can salvage magnets from old computer hard drives, but disc magnets are ideal, if you can find some. I use a disc shaped magnet about the size of a nickel. Then I “capped” the magnet with a metal slug. Glued everything in place with a glob of contact cement.

About rare earth magnets. DID YOU KNOW that you can in

crease the attractive power of these magnets by putting a piece of iron (or steel) behind it. Any piece of steel the same size or larger than the magnet will do. For maximum effectiveness, be sure the steel is at least as thick as the magnet. Several layers can be used if necessary. http://www.leevalley.com/shopping/Instructions.aspx?p=54198

(Just click on the country tab in this link, and the image will open up automatically.)

In the photo above, you should be just about be able to see a steel washer I used to "cap" a disc magnet about the size of a quarter coin. Steel slugs the same size, or slightly larger than the magnet would work better, but washers work okay, and washers are easier to find. A three-foot strip of ribbon rolls up quickly and the ribbon fits inside the hollow of the egg.

Now, you can toss it down field in front of you for those variable, low-wind, forward launches, clip it to a post, or to the top of your car, anything metal. You could attach a small steel hose-clamp to the motor's aluminum cage, or a small steel ring, cut from a tube, split and epoxied on a discrete part of the top quarters of your cage ring.

Your Weeble can wave wind-direction to other flyers if you're just waiting around.

Remember, you can't have too many wind indicators on the field.

Car Aerial Streamer

A bit of tubing. Whatever fits over the aerial on your vehicle, which might be a different size than mine. I used 1/4 inch fuel line about four-inches long, some JB-Weld, a fishing swivel, and a three-foot long nylon streamer.

I don't drive around with the thing flapping all the time - I keep it in the glove compartment - but I slip it over the arial whenever I'm para-waiting, or parked near where I'm kiting or flying.

I always say that you can't have too many wind indicators around.

ON the topic of streamers, as wind indicators go they are said to have a unique advantage for indicating bumpy air. A European PG pilot posted that they commonly use 2.5 meter steamers made of silk ribbon, and free fly if the streamers are flowing straight and steady, but are cautious if they develop "serpentine" shapes, which indicates gusty, and bumpy air.

Packable Wind Sock Pole

Bruce Brown, of Flyohio.com makes a very nice, big, but lightweight, and easy set up pole and wind sock combination. You can make a homemade unit or units using these tips for free, however, as I’m of the opinion that you cant’ have too many wind indictors on the field.

I recycled an old two-person tent to make this. The tent itself, became a dust cover for my motor unit, and I used two of the ten-foot, shock-corded, tent poles to make my wind sock pole. Each section of these poles were originally only 24” long, but I wanted the collapsed length to fit into a small backpack. I cut the end off one pole, and removed the elastic shock-cord, and cut each section in half, to make ten twelve-inch sections. The pole is still ten-feet long, (actually just under 12 feet, if you count the ground peg/support) but it is significantly more portable.

The second pole was canibalized for parts, to salvage the metal end pieces, and I attached these pieces to the cut ends of the first pole. Then I just rethreaded the shock cord, and reassembled the lengths tying the cord at the bottom.

I even J-B Welded some small D rings, as guy line attachment points,at about the six foot mark, but I almost never peg it down.

The ground stake is an eight-inch length of steel rod, JB-Welded into a bit of aluminum tubing. Another tube nested in the base, gives a relatively solid base for my pole. It bows significantly in high wind, unless you guy line it to tent pegs, but that’s no big deal, and I almost never bother.

A fishing swivel, (Walmart - 3 for $4.00) fastened on one end with JB-Weld, is my free swiveling wind sock attachment.

(An aside about JB Weld… the company makes two related products: JB Weld and JB Quick. The Quick sets up in about 5 minutes, but isn’t as rock solid as the Weld which takes about eight hours to cure. I recommend the latter for virtually everything.)

Homemade Wind Sock

Many different materials can be used to make homemade wind socks. The bags new gliders come in is the same material that wings are made out of and can make a couple of nice little socks if you don't mind cutting it up. I've made them out of old tent material, and a cut-up kid's kite. In fact you can use just about any lightweight nylon, or ployester you may find lying around, or just buy a yard or two from the fabric store. Polyester flag bunting was recommended on one site.

Don’t sweat the shape overmuch... this isn't rocket science.

Well, actually, NASA has developed mathematical formulae for aspect ratio and taper, and the document FAA SPECIFICATION FOR WIND CONE ASSEMBLIES,
http://www.faa.gov/airports/resources/advisory_circulars/media/150-5345-27D/150_5345_27d.pdf
is six-pages of advisary notes detailing size, fabrication, photometric requirements, specifications on taper for their socks.  Here's an excerpt: "The taper or the fabric windsock from the throat to the trailing end must be designed to cause the windsock to fully extend when exposed to a wind of 15 knots (28 km/hr or 17 mph)... and etc... and blah blah."

So it really is rocket science, it's just that, for our purposes, it's EASY rocket science.

I mean come on, little kids make these things out of construction paper.

The FAA has an actual link to a diagram for little kids to make them right here - (On Page 151)
http://www.faa.gov/education/educator_resources/curriculum/k_3/media/sc3.pdf
and their little diagram is as good as any thing else you are likely to find online.

Just freehand out the shape, cut with scissors, hem the sides and ends, and then turn it inside out and run a line of stitches down the length. Sew seams on the top and bottom.  The scoop hole should be about twice the diameter of the exit hole. If you want, you can add a few strips to make streamers to give an extra bit of length and noticability.

Your choice of material will affect your windsock's performance. Ideally, you want a "steady" wind sock when there is a steady breeze. If you don't, then take it home again and change the aspect ratio or the taper or both. (A large inlet hole relative to a short length means a moderate aspect ratio.) Paraglidingforum.com had some tips on windsocks which I list below:

-Very little taper is needed to get a steady wind sock, if and when the fabric is light and non- porous.
-If a wind that should be able to lift the wind sock, can not, then make it shorter.
-If the wind sock flaps, make it narrower towards the outlet hole. Flapping causes an unnecessary increase in wear and tear.
-For larger socks, softer and heavier materials (as opposed to crispy, ripstop nylon), will better withstand higher winds. However, with heavier material, more taper is needed to "inflate" and lift the wind sock.

To hold the scoop end open I used a length of coaxial bicycle brake cable. The cable is usually in three parts: strip off the rubberized coating and discard. The cable itself is made of braided wire inside a flexible metal sleeve. The wire is what you want. But keep a tiny 1/4 - 1/2" piece of the metal sleeve material to connect the two ends into a loop.  (Once you thread it into the sewn hem of the scoop end of your finished wind sock.)

Feed alternate ends of your wire into that bit of sleeve material, and seal it up with JB Weld, epoxy, or some other kind of heavy duty adhesive. If the sock I'm making is less than 12 inches in diameter, as is the sock below, (This mini-sock is only 6" in diameter) I might untwist a strand, or two, or three to reduce the effective guage of the braided wire and make it a little bit lighter.

Where do you get bike cable for free?  A bike repair shop may have a few feet lying around that you can have for the asking.  Every day, I drive by bikes that have been stripped of parts, and have been abandoned by their previous owners.  These sad, rusting, skeletonized relics, probably still have some brake cable atatched, and after a point become legitimate salvage as far as I'm concerned.

Here you can see some construction dtetails, where the cable is looped into itself, (cemented into a 1/4" piece of the flexible metal sheath from the bike cable), after being threaded into the hem at the sock's throat end.

You can also see one of three grommets I set to attach string, but this step can be eliminated if you don't have a simple grommet setting tool and grommets.

On the base, next to the pile of streamers sewed onto the narrow end of the sock taper, is an old glasses case where I keep this pocket-sized wind sock, and a mini-telescoping pole (see list) to ground mount this sock 24 inches off the ground, or attach to a car aerial.

If you can't seem to find bike cable, you can also try cutting a thin hoop of flexible plastic from a plastic jug, and thread this through the hem at the throat of your sock to make a semi-rigid opening, but the beauty of this spring steel cable, is that you can fold the scoop end opening into a figure eight, and fold the two ovals back on themselves in the same way a photographer folds up a light reflector.

This halves the diameter of the sock for easy storage, and the cable always pops back into a large, perfect circle again, every time.

A final touch is to add a fishing swivel to the end of the three stings. This swivel clips to the swivel on the end of your pole, or other sock mount, and helps keep the sock cords from tangling.

Another technique, for a larger sock, is to use four, 6" wire fishing leaders.  Three of them are attached to the sock itself, and connected to a fourth where the three ends come together.  Easy, and the wire leaders never tangle up like string does sometimes.

My main wind sock is one meter long.  This mini-wind sock is designed to fit in a pocket. The sock itself is 12" long with four 12" long streamers. The throat opening is 6" in diameter, which folds down to a 3" diameter, that fits with the 24" telescoping mini-pole into a typical case for glasses. The fold is familiar to anyone who has folded a photgrapher's light reflector. Grap the wire as shown below - the 6" hoop into a figure-8, and then fold the two half-sized hoops of the eight onto themselves, to make a 3" diameter hoop which fits readily into a small case.
I like adding a few streamers to windsocks, because it helps to identify the tip end at a distance when you are up in the air.  It's not uncommon for wind direction to shift even as much as 180 degrees in a short time, and some long windsocks, and one-piece streamers, while visible from the air, may not reveal actual direction till some altitude is given up.   

Bifocal mod for goggles

I like these ESS Profile goggles for flying. They are current-issue military surplus, with lots of them available from troops returning from overseas. Typical price on ebay is around 25 dollars.

The thick impact resistant lenses have natural UV protection in the polycarbonate, so you are UV safe, even with the clear lens. Lenses switch out easily, and you get both clear and smoked, sunglass lenses when you buy the goggles, and high-contrast amber lenses can be ordered from Optics Planet for use on cloudy days. I actually bought two pair of goggles, however, to eliminate the need to switch back and forth from clear to smoke.

Profile goggles also have wide "outrigger" strap attachment points which makes them suitable for over helmet use. and I cemented a piece of loop Velcro on the strap, and another piece of hook Velcro on the helmet, to keep it secured at the back.

Another selling feature for me was the fact that Profiles are availble with an RX insert.

A typical prescription and an insert can be had from Optics Planet online, for about a hundred dollars, but bifocal prescriptions aren't available. Your optometrist can easily make one for you in a bifocal RX, if you give him the insert to measure, but I found out that would cost 200 to 300 dollars here in Canada.

One inexpensive option to bifocal both goggles, and regular sunglasses are with stick on lenses from Optx2020. Available locally at Lee Valley for 14 dollars, (June 2010) and also ebay for around the same.

They are available in reading strengths from .5 increments from 1 up to 3. Removable, and reusable, they just go on and off with warm water. About 12 bucks on ebay for a pair, although I just installed the one on my dominant right eye. I stuck the other on a set of smoke lenses.

Problem is, they are getting nearly impossible to find anymore.  They may be discontinued, I don't know.  The company didn't return my email, and Lee Valley Tools, has stopped carrying the product.

You can still find a few online, if you look hard enough, however.

I had previously modded a plastic reading lens onto my flying goggles, shaped the lens with a Dremel cut-wheel, and fixed it into a groove on the bottom witha bead of silicone. Modifying a plastic reading lens, was basically free, and works okay, but these Optx lens things are a pretty nifty ready-made solution ata fairly affordable price.