Why do Racer owners think their rig would offer the fastest reserve openings?

[fcajump 164]

Quote

It's not just one factor (the pilotchute being externally mounted for example), that affects speed of reserve deployments.

In the case of the Racer, it's the fact that the reserve container opens more freely and completely, has no boxed corners where it counts, has a very bullet-shaped reserve deployment bag, and has a higher drag pilotchute. "Higher that what?" you may ask.

Well, in wind tunnel tests, conducted at the NASA Ames Research Facility, the Racer pilotchute demonstrated an 84% drag efficiency. Other pilotchutes that we brought along, and also tested averaged between 40-60%. We used NASA's finely calibrated load cell that was mounted in the tunnel.
The Racer pilotchute "stops" better - has greater "snatch" - however you want to say it. It doesn't "slip" through the air as much, in other words.

Nancy,

I think we would all (OK... some of us geek types) would be interested in seeing the data collected and what make/models were tested.

I understand that this is only one component of what makes the system open faster/slower, but it all starts there.

JW

Always remember that some clouds are harder than others...

[Slurp56 0]

I'd interested to know as well. I was having a conversation about this post earlier and we got to thinking that efficiency doesnt really mean a whole lot by itself. I am curious to see what kind of numbers were collected on force generated.

________________________________________
I have proof-read this post 500 times, but I guarantee you'll still manage to find a flaw.

[sid 1]

Quote

I'd interested to know as well. I was having a conversation about this post earlier and we got to thinking that efficiency doesnt really mean a whole lot by itself. I am curious to see what kind of numbers were collected on force generated.

we've been collecting data for John (Sherman) over the last few weeks for a presentation he's giving at PIA in Feb. Not specifically reserve data, but opening data collected via a datalogger..... once the presentation is over I think he may have me post it on the jumpshack website. I'll post here as soon as I know for sure....

Pete Draper,

Just because my life plan is written on the back of a Hooter's Napkin, it's still a life plan.... right?

[peckerhead 0]

Because they need to say something to justify having such an outdated obnoxious rig.

[BlueSBDeath 2]

Quote

Racer is ugly...
But deamn comfortable...
but ugly

Have you seen this Racer ad?

Love those Racers

Arvel

BSBD...........Its all about Respect,

USPA#-7062, FB-2197, Outlaw 499

[mark 107]

Quote

Have you seen this Racer ad?

I heard (from a FOAF) that the handle in that ad was attached to the nose of the center cell of a Unit -- no main pilot chute. Is that true?

Mark

[BlueSBDeath 2]

That is a very cool story, I have no idea if it is true, Nancy...........any input??

BSBD...........Its all about Respect,

USPA#-7062, FB-2197, Outlaw 499

[parafredo 0]

I think there is two debate over here.Please,do not compare any reserve pilote chute against the Skyhook system.Don't make it confusing for newbies

[peckerhead 0]

Quote

Quote

Have you seen this Racer ad?

I heard (from a FOAF) that the handle in that ad was attached to the nose of the center cell of a Unit -- no main pilot chute. Is that true?

Mark

It was not uncommon back in the day....

That photo was also taken with a lens capable making it look a lot lower than reality.

[Slurp56 0]

Quote

Quote

I'd interested to know as well. I was having a conversation about this post earlier and we got to thinking that efficiency doesnt really mean a whole lot by itself. I am curious to see what kind of numbers were collected on force generated.

we've been collecting data for John (Sherman) over the last few weeks for a presentation he's giving at PIA in Feb. Not specifically reserve data, but opening data collected via a datalogger..... once the presentation is over I think he may have me post it on the jumpshack website. I'll post here as soon as I know for sure....

I've only briefly looked over the schedule, but it looks like jumpshack is hosting a couple of seminars. Do you know which one this information will be presented at? Thanks.

________________________________________
I have proof-read this post 500 times, but I guarantee you'll still manage to find a flaw.

[sid 1]

Quote

I've only briefly looked over the schedule, but it looks like jumpshack is hosting a couple of seminars. Do you know which one this information will be presented at? Thanks.

I believe it's called "The Anatomy of an opening" I think he'll have the datalogger and the vest that we wear to hold it connected to the load cells and altimeters on hand to show people, and I think they'll also have that for view on The Jump Shack stand. I got a sneak preview of the presentation the other day (he's still adding to it" and it's well worth checking out....

Pete Draper,

Just because my life plan is written on the back of a Hooter's Napkin, it's still a life plan.... right?

[Jeffrey 1]

Mark,

The jumper in that old Jump Shack ad was Nick Lukas, and yes, his Pull-Out lanyard was in fact attached to the center cell of his Flyer. Many of us were playing with that back then. The photographer was probably Kevin Shay. Sad to say but both of them died at an early age.

Jeff

[riggerrob 643]

That might have been relevant back when everyone was using military-surplus MA-1 pilotchutes and many of Jump Shack's competitors were still trying to figure out how to build rigs without brass cones.
Hee!
Hee!
Remember that the military specified 18 pound springs in MA-1 pilot chutes and sold them when springs weakened. Some of those weak springs had difficulty pushing four or more flap stiffeners out of the way.
Now that most of Jump Shack's competitors are using springs far stronger than 18 pounds, spring strength is less of an issue. Ergo, large, modern Vectors, Mirages, Infinities, etc. have inflation times within a few hundredths of a second of Racers.

Now they are learning - the hard way - a lesson that Rigging Innovations learned 15 years ago. The problem involves rigs getting narrower and narrower every year, but springs retaining the same diameter. For example, it is easy for an 6 inch wide spring to punch out of a 16 inch wide container. But difficult for that same 6 inch wide spring to punch out of a 9 inch wide container.
When R.I. encountered that problem on B-width Talon Mark 1 containers, their first response was stronger springs. R.I.'s long term response was 5 inch wide springs and a completely new generation of containers (Flexon, '94 Talon, Talon 2, Talon 3, Talon FS, Voodoo, Telesis 2, Telesis 3, etc.)

[Jeffrey 1]

Quote

Now they are learning - the hard way - a lesson that Rigging Innovations learned 15 years ago. The problem involves rigs getting narrower and narrower every year, but springs retaining the same diameter. For example, it is easy for an 6 inch wide spring to punch out of a 16 inch wide container. But difficult for that same 6 inch wide spring to punch out of a 9 inch wide container.

Rob,

That’s not necessarily true if the reserve container is designed with the corners are running North and South like on a Mirage.

Jeff

[TMPattersonJr 0]

The next intentional cutaway I do on JumpShack's Double cutaway rig I'll mount my camera backwards with a fisheye lens and let you be the judge on how fast or slow the openings are. I watched a few Skyhook demo's a few weeks ago in Palatka and yes the extraction is pretty quick but you are so subterminal it looks like it takes the canopy a few more seconds to inflate (going back and looking at the video I did of one of them it took 4 seconds from cutaway to Full reserve inflation.) On my intentional cutaway I had a sub 3 second reserve deployment, and that was from pulling the reserve handle to fully open reserve parachute. I'm not going to say that The Racer has the fastest opening on the market but it is definately going to be my rig of choice.

Blue SkiesBlack DeathFacebook
www.PLabsInc.com
www.SkydiveDeLand.com
www.FlyteSkool.ws

[deadwood 0]

Which "other" pilot chutes?

[Well, in wind tunnel tests, conducted at the NASA Ames Research Facility, the Racer pilotchute demonstrated an 84% drag efficiency. Other pilotchutes that we brought along, and also tested averaged between 40-60%. .

[Slurp56 0]

Quote

Quote

I've only briefly looked over the schedule, but it looks like jumpshack is hosting a couple of seminars. Do you know which one this information will be presented at? Thanks.

I believe it's called "The Anatomy of an opening"

I didnt see that one on the lineup. John Sherman's got one called "Addressing Opening Shock Problems." Think thats the one? There's another one on the 8th called "The use of load cells during R&D Parachute evaluations" but that is put on by Ignatius (Kappie) Kapp.

The lineup can be found here for refference:

http://www.pia.com/Symposium2007/downloads/PIA/speaker-tables.pdf

________________________________________
I have proof-read this post 500 times, but I guarantee you'll still manage to find a flaw.

[sundevil777 102]

Quote

The next intentional cutaway I do on JumpShack's Double cutaway rig I'll mount my camera backwards with a fisheye lens and let you be the judge on how fast or slow the openings are. I watched a few Skyhook demo's a few weeks ago in Palatka and yes the extraction is pretty quick but you are so subterminal it looks like it takes the canopy a few more seconds to inflate (going back and looking at the video I did of one of them it took 4 seconds from cutaway to Full reserve inflation.) On my intentional cutaway I had a sub 3 second reserve deployment, and that was from pulling the reserve handle to fully open reserve parachute. I'm not going to say that The Racer has the fastest opening on the market but it is definately going to be my rig of choice.

I think the only useful comparison that can be made is to look at the time to get the canopy clear of the freebag. Of course the airspeed at the time of cutaway can affect the result.

People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am

[teason 0]

It would be pretty bad form to slag the other manufacturers products by name publicly in an open forum.
Nancy is a manufacturer, not an average jumper who can just blast opinions on the net.

Nancy has shown professionalism by just saying that their PC had a higher Coefficient of drag than other PCs tested.

I would rather be a superb meteor, every atom of me in magnificent glow, than a sleepy and permanent planet.

[sundevil777 102]

She could still give the actual drag force instead of just the efficiency. Efficiency means nothing by itself.

Also, I wonder how they define "efficiency". I think the term may have the same definition as coefficient of drag.

People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am

[teason 0]

The post was probably written with the layman in mind but yes, the results show coefficient of drag.

I would rather be a superb meteor, every atom of me in magnificent glow, than a sleepy and permanent planet.

[sundevil777 102]

So, the actual drag figures could be published, just saying brand X = ? pounds, brand Y = ? pounds...

People are sick and tired of being told that ordinary and decent people are fed up in this country with being sick and tired. I’m certainly not, and I’m sick and tired of being told that I am

[sid 1]

Quote

I didnt see that one on the lineup. John Sherman's got one called "Addressing Opening Shock Problems." Think thats the one? There's another one on the 8th called "The use of load cells during R&D Parachute evaluations" but that is put on by Ignatius (Kappie) Kapp.

The lineup can be found here for refference:

http://www.pia.com/Symposium2007/downloads/PIA/speaker-tables.pdf

that's probably it..... you know how things go, you start with a working title then........

Pete Draper,

Just because my life plan is written on the back of a Hooter's Napkin, it's still a life plan.... right?

[dorbie 0]

Quote

>I'm wondering if they are right and why this could be true.

Ask Bill Booth about the racer vs vector drop tests they did years ago. It's informative _and_ a great story.

From the Jump Shack website:

"In tests, the Racer/Elite deployed reserves in an average of one-and-a-half seconds faster than any other system currently available. At terminal velocity, 1.5 seconds translates to 264 feet."

Also from the same web page:

"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. "

That helps explain why their customers hold the belief mentioned in the subject heading, but I'd love to hear Bill Booth's take on those drop tests.

[billbooth 10]

I thought this was settled a long time ago. No modern sport container system deploys, to line stretch, faster than any other. This fact was determined years ago in side by side tests. You can cheat on the tests by "front risering" for greater airspeed just before breakaway, or by packing for an extremely fast canopy inflation...but the fact remains: Given the same conditions, all modern gear performs about the same. The fact that we are still discussing this worn out topic, simply proves that the old saying is true: "A lie, repeated often enough, becomes legend". You can't believe everything you read on the internet, guys...Honest!