Technical Articles

1. Why is the Racer Reserve pilotchute on the outside of the container?

The externally mounted reserve pilotchute provides for direct deployment of the pilotchute into the air stream without having to push any flaps out of the way. It is simply the fastest and most direct initiation of canopy deployment available today. In tests, the Racer deployed reserves in an average of one-and-a-half seconds faster than any other system currently available, with or without the aid of a MARD or RSL. At terminal velocity, 1.5 seconds translates to 264 feet.

2. Why do your Elite and N.O.S. have riser covers which are different?

We believe in offering as many choices as possible (within reason). We offer the fully Velcro-sealed riser covers of the Racer/Elite, which are preferable for radical flying, because they make toggle and riser escape impossible. This design also allows the Racer/Elite container to actually bend and flex. No other container bends and forms to the body like it. The Elite 2000 features 'trough' type riser covers for fast easy packing, but are less reliable than the Velcro sealed riser covers for preventing riser and toggle escape. Both models came into being as a result of our development of the Narrow Over the Shoulder option. The N.O.S. was developed for the many women and jumpers with slighter builds, who needed a closer fitting yoke to prevent the rig from sliding off the shoulders.

3. What is Type 13 webbing and why don't the other manufacturers use it?

Type 13 webbing was developed to be compatible with the current use Mil. Spec. hardware that is used in personnel delivery harnesses. Type 13 (black trace edge) webbing (7000 lb. tensile strength) is still the ONLY webbing that is truly compatible with the industry standard hardware. Other manufacturers use the less expensive Type 7 (yellow trace edge) (6000 lb. tensile strength), which was intended for cargo netting/harness use, and didn't involve the use of personnel-specific hardware. Unlike the thicker Type 13, Type 7 has a tendency to slip in the hardware. Type 8 (black trace middle) (3500 lb. tensile) is also used by some manufacturers in main lift web and leg strap applications. Jump Shack only uses type 8 in chest strap and riser applications, where expected operational loads are acceptably low. If you take a look at a harness produced by Sun Path, you will find a very interesting application of Type 8. They found that their Type 7 harness needed backing with Type 8 in order to prevent slipping in the friction adapter hardware. Take a look at the leg straps- you'll see. In fairness though, they're not the only ones using this method to make cheap Type 7 compatible with personnel hardware.

4. Does it really matter that you manufacture to Mil spec? Aren't the others good enough?

That's for you to decide. We think not. We believe that there is no reason to use less than the best materials when manufacturing parachute equipment. As a result of our extremely high quality standards, we are the sole supplier of parachute equipment to the British government. It is unfortunate that our own government has ultimately chosen to ignore its own guidelines by purchasing non-mil-spec equipment from other manufacturers. The purchasing of non-mil-spec sport equipment evolved as an attempt to spread the economic benefits of government contracts throughout the industry. The U.S. military only purchases mil-spec equipment for tactical operations, but has withdrawn the specification requirement (which no manufacturer other than Jump Shack would meet), from sport and demonstration uses.

5. What is a 'fail safe' harness?

A fail safe harness is one that you wouldn't fall out of if there were a primary stitch failure. The Racer line was designed to be the safest, most effective reserve deployment platform in the world. It is. Any sewn junction can rupture and the occupant will still be retained by the unit. Our harness is completely unique. It's not patented. It's not complex. In fact, it's only four pieces of webbing that are constructed in a manner that will never let you come out before you're ready. Ask another manufacturer if they can truly make this claim. They can't.

6. Why is your harness the most comfortable I've used?

In a word: geometry. Geometry is key when designing a harness whose principal consideration, after strength, is to sit you in a natural and supportive position. The harness must encapsulate you - front and back- not just harness in front, and container on the back. The Racer incorporates the only harness with a lumbar strap that takes up a portion of the wearer's weight from the leg straps. Type 13 webbing also plays a part in comfort. Its edges don't roll under as a result of lateral stresses in the way that the lighter Type 7 and Type 8 do. Type 13 has a heavier 'hand'. Sizing is also of paramount importance to the user's interface with the rig. We size our harnesses in three dimensions: the shoulder and the main lift web and horizontal. Other manufacturers don't even allow the shoulder variable, except in extreme cases. We, on the other hand, use the shoulder measurement as the foundation for the correct fit of each custom harness. Every harness is built to the customer's exact size, and if it isn't comfortable we will rebuild it-this is our commitment to every patron and is our unconditional guarantee.

7. What is the significance of hardware/Type 13 compatibility? The Javelin uses Type 7 backed by Type 8; isn't this stronger and better?

Not necessarily, and strength isn't the only issue. Sun Path has to use two layers of webbing to get their harnesses to work correctly, when only one layer would do the job. One layer of webbing is obviously lighter and more comfortable than two. Many Type 7-based harnesses exist as examples of a bad design which was made to work through the application of Type 8 Band-Aids. Type 13 does cost more, but cost wasn't a design consideration when we set about creating the safest harness/container system in the world. When nylon became available, cotton webbing and tapes were phased out of production. Type 13 was designed for use with the existing hardware and remains the only webbing which meets mil-spec for personnel carrying harnesses. Practically, Type 13 works with the hardware because it was designed and engineered for that exact application. We have a hard time explaining the reasons that others don't use Type 13; it appears that most Type 7 harness designs are basically copies of the early Wonder Hog design, which proved successful for the Relative Workshop. Type 13 is the obvious choice for the construction of strong and functional harnesses, but manufacturers that make copies can't always see the obvious.

8. Hasn't the Reflex improved on your design by using only one pin to close the reserve?

Not at all. Jump Shack has had a patent for several years on the one pin, and made a very conscious decision not to market it. We developed, tested, and jumped a number of versions of the one pin pop top and actually rejected the design used on the Reflex years ago. One pin pop tops have a tendency toward excessive ripcord pull force. The Tear Drop rig has this flaw, and is, therefore, not TSO certifiable. The one pin pop top is susceptible to tampering- a half twist of the pop top hat will double an already unacceptably high ripcord pull force. There is, in fact, a significant loss of performance when the pilotchute is retained with one loop, as opposed to two. There are a number of failings in the one pin pop top concept - but the main shortcoming is the additional weight of the reserve pilotchute caused by the necessitated reinforcement across the top of the spring. Tests were conducted where the pilotchute from a Tear Drop container actually fell away from a jumper in a cutaway situation. The metal reinforcement in the top of the pilotchute caused it to have such mass, that it accelerated with the jumper for almost three seconds before inflating. In that period of time, a Racer could deploy its reserve almost twice. Having one pin does not make for a better or more functional product. So why does it exist? We can't really say. Safety is, and has always been, the number one priority at Jump Shack. Those who don't know history are destined to repeat it.

9. So your reserve pilotchute has a Cd (coefficient of drag) of over .8, and the others' are as low as .3; don't they both work just as well?

No. The coefficient of drag is effectively an efficiency factor or a percentage rating on efficiency, or inefficiency if you're stream lining. Cd represents the percent of the effective surface area. If two canopies have the same surface area, then the one with the highest Cd will drag the most in the same air stream. Thus, quicker reserve deployment. It is somewhat interesting to note that when the Porsche 944 came out in 1983, Porsche had done what no other car manufacturer had been able to by creating a car with an extremely 'clean' (read slippery) Cd rating of .31. The Vector pilotchute, which was presumably designed for high drag, has a Cd in the mid .3s. In plain language, the Racer Pilotchute drags 200 lbs at 120 mph (or terminal). Our leading competitor's pilotchute drags 70 mph at 120 mph (terminal). Combined with the tapered Racer Reserve Deployment Bag and unfettered Yoke Flap the result is faster bag extraction and an overall faster, more reliable reserve deployment!

10. Why has the Racer remained almost unchanged for nearly thirty years?

When you get it right the first time you don't have to change it.

The mechanics of the rig have not changed. The rig has become more clean and streamlined, but at the Jump Shack, we subscribe to the continuing evolution of a revolution that we created over 30 years ago. Many small refinements have taken place over a three decade period that have resulted in the most tested and time proven parachute delivery system on the planet.

11. I've been told 3 different ways to close your main container; which is right?

One of the Racer's original design constraints (safety), precluded us from building a main container that could be packed incorrectly. One of the most dangerous malfunctions a modern skydiver can have is the dreaded pilotchute-in-tow as a result of an incorrectly routed throw-out bridle. Every other rig on the market has a main container failure mode associated with incorrect closure. Why build a rig like that? It's really simple to make a container which closes right no matter how you do it. Develop a bridle routing sequence which works for you-it'll be as right as any other.

12. My rigger says he hates to pack Racers. Shouldn't I get a rig that's 'rigger friendly'?

No, you should get a rigger who is Racer friendly. Riggers who have studied their craft and who do it professionally, actually prefer to pack Racers because of the easy closing sequence and the convenience of the Quick Loop. As we have stated through out this paper, the Racer was designed to the highest standards of safety and function. It wasn't designed to pack like the others. It wasn't designed to be the easiest to pack. It was designed to be the fastest in the world. It is. We average less than half the deployment distance of any other rig available-about 90 feet versus in excess of 200 feet for the others. Those are the facts. Period. When it REALLY counts-below 200 feet-the Racer, not your rigger, will be there for you. If a rigger claims the Racer is “hard to pack”, listen carefully; he is really saying something about himself! Riggers are supposed to be able to read and follow directions from an Owners Manual. And now that we have a step-by-step DVD packing (video) manual, Racer packing is easier than ever.