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Reserve vs Main

 


cpwaters  (B License)

Jul 12, 2001, 11:35 AM
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Reserve vs Main Can't Post

Is there a recommended maximum size difference between the main and reserve and should one or the other be smaller?



Grogs  (D 24265)

Jul 12, 2001, 12:38 PM
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Well, there are 2 schools of thought on the subject. Some people claim they should be of similar size so that one canopy isn't spinning circles around the other in a 2 canopy out situation. Others believe that you should have a larger reserve because if they get into a bad situation (knocked unconcious, arm dislocated, etc) the reserve should still be able to land them relatively unhurt even if they can't flare.

Most people jump with a reserve that's about the same size as the main just because that is how most stock containers are built. To put a large reserve and a tiny main in the same container, you generally have to have it custom built (if the manufacturer will do it at all).



Premier PhreeZone  (D License)
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Jul 12, 2001, 2:56 PM
Post #3 of 10 (968 views)
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Mines in the opposite situation. Larger main then reserve. I'm getting ready to downsize both of them too. I've landed smaller canopies then my new reserve so its not an issue with me. My only concern was exceding the placard weights on it.

Whoa... That was cool!


PalmettoTiger

Jul 12, 2001, 7:00 PM
Post #4 of 10 (936 views)
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Re: Reserve vs Main [In reply to] Can't Post

In reply to:
I've landed smaller canopies then my new reserve so its not an issue with me.
Did you land them without flaring (as if you were unconscious)? If the new, smaller reserve will be loaded heavily enough to put you in harm's way w/o a flare, you may not need to downsize that reserve.

Blues, squares,
PTiger

"Beer: the OTHER other white meat."


craddock  (D 22750)

Jul 12, 2001, 7:17 PM
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Re: Reserve vs Main [In reply to] Can't Post

This is a very common arguement but I do not buy in to it. How many people land unconscious under their reserves? Seriously. Even more to the point-how many survived?
I have very little chance of being unconsious under canopy(unless I have a seizure) but I still jump a reserve much larger than my main.
J.
btw- my reserve is a pd106




Merrick  (A 38462)

Jul 13, 2001, 6:00 AM
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Re: Reserve vs Main [In reply to] Can't Post

In reply to:
"This is a very common argument but I do not buy in to it. How many people land unconscious under their reserves? Seriously. Even more to the point-how many survived? I have very little chance of being unconscious under canopy"
Don't be so sure... I'd never actually read the Cypress saves before someone posted the link on here the other day, and over half of the 'saves' were from no-pulls, and a HUGE majority of those were due to the person being unconscious... for whatever reason (one guy even hit his head on the tail of the plane & was unconscious for several minutes even after he landed)!

The debate over large reserve/small reserve is just as big as the one over cypress/no cypress... Why do I jump with a cypress?? Because in the unlikely event that someone takes me out, or the pilot bobbles the plane & I hit my head on the tail therefore rendering me unconscious... the same reason that my reserve is as big as it is.

"If words were wisdom, I'd be talkin' even more.."


craddock  (D 22750)

Jul 13, 2001, 6:41 AM
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I have never read the cypress webpage, but I wonder how many of the unconscious saves remained that way after opening untill landing. You have pointed out one and there are probably others but statistically I will take my chances. Even more so since I don't jump with an AAD.
Blue Skies
J



Premier SkymonkeyONE  (D 12501)

Jul 13, 2001, 6:53 AM
Post #8 of 10 (883 views)
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Re: Reserve vs Main [In reply to] Can't Post

In reply to:
Most people jump with a reserve that's about the same size as the main just because that is how most stock containers are built. To put a large reserve and a tiny main in the same container, you generally have to have it custom built (if the manufacturer will do it at all).
Not really true Grogs. Actually, on the smaller end of the spectrum, all rigs are available with bigger reserve containers than mains. For example, my Jav Odyssey RS is built for a sub-100 main and a reserve up to a Tempo 120. Most smaller sizes in all containers are this way. Also, you can get plenty of containers in larger sizes (Vector III and Mirage for sure) that meet the same criteria. Why this is available in that case is because there are PLENTY of people over 200 pounds that are jumping mains smaller than 100 square feet, but very few of those people would be happy landing a PD 113 reserve. You can get containers now that fit a 150 reserve and a sub-100 main.
On the smallest end of the scale, where I buy, the reason I jump my reserve is that there is not a container built (that I am going to buy anyway) that my Tempo 120 won't fit in. If there was a smaller one, then I would buy the container and that much-smaller reserve. I only weigh a buck and a half, so I have no fear of landing small reserves.

Chuck





Grogs  (D 24265)

Jul 13, 2001, 7:34 AM
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Re: Reserve vs Main [In reply to] Can't Post

Ok, thanks for the correction Chuck. I thought most of the containers kept them pretty close for aesthetic reasons, but I would have to say a 79 main vs. 120 reserve is a pretty big difference.

As for landing unconcious under a reserve, I counted 9 incidents on the Cypres saves page, and from the look of it they were all unconcious upon landing. There were also 2 jumpers who dislocated arms and (probably) weren't able to flare upon landing - the injuries ranged from broken legs to nothing at all. Those only the ones listed on the Cypres saves page, but I'm sure there have been others that weren't on there, and I'm sure there have been jumpers who landed under a reserve without flaring who didn't survive (such as the heart attack earlier this year).

That said, I'm not advocating one philosopy or the other, merely stating what they are. It's your butt hanging under the chute, so whether you choose a 46 or a 288 square foot reserve, if you're comfortable with it, more power to you.



miked10270  (D 10270)

Jul 13, 2001, 3:57 PM
Post #10 of 10 (848 views)
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HI there,

This is ONE opinion, from ONE school of thought... MINE!!!

My argument is that while there have been major technological advances in main canopy development in the last 16 years (like 9-cells, ZP, elliptical, cross bracing, airlocks) which have resulted in more efficient canopies which can be safely flown at higher speeds and higher wing loadings, reserves have effectively been stuck in a time warp. They are almost invariably 7-cell F-111 canopies (effectively from the "Fury/Pegasus" era - the early 1980's).

SPeaking as someone who blew an ankle apart trying to land a 220 Fury like a Sabre... THESE (reserve) CANOPIES DO NOT FLY LIKE MODERN MAINS!!! 7-cell F-111 mains were not produced in sizes significantly less than 200sq.ft and were not intended for wing loadings significantly greater than 1.0lbs/ft2.

My argument is thus: If you are under your reserve then something has already gone to shit. you are probably already upset at the implied costs of you being under your reserve ($60 - $2,000) and are probably 90 seconds or less from landing. This is not the time to try to learn to fly and land an unfamiliar highly loaded canopy with significantly different construction and (hence) flying characteristics from the one you are used to! At this tme you want a nice, safe, tractor of a canopy. So... exit weight (lbs) equals minimum reserve canopy size (ft2). This assumes you are fully conscious... If not, then would you land a heavily loaded canopy downwind at quarter brakes with your eyes shut and expect to survive, 'cos that's where you're going if you're unconscious under a Cypres fire!!

Mike D10270.




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