Reserve size in Relation to main

[CMiller 1]

I've heard that it's dangerous to jump a reserve much smaller than the main (or is it vice versa). Should the reserve be smaller, or bigger? If so, by how much?

What exactly is the danger of having the two canopies be significantly different sizes?

How do you determine what size reserve you should have if you know the size of your main?

I ask this because many of the used rigs I've looked at can supposedly handle different sized main canopies, and I'd like to know if changing that would be dangerous.

[Orange1 0]

i'm just as new as you in the sport so take my words with that in mind... but 2 things spring to mind. The first is that in a situation you have pulled your reserve you are likely to be pumped up, may be landing out etc and having to deal with a smaller canopy than you are used to flying may make the situation worse.

The second is the event of a 2-out, where i understand a SBS will be more stable if the canopies are the same size - possibly a biplane too but i'm not sure - hopefully a poster with more knowledge will expand on this point.

Skydiving: wasting fossil fuels just for fun.

[Reginald 0]

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How do you determine what size reserve you should have if you know the size of your main?

More tomorrow as it's been a long weekend. But you choose the size of your reserve first, then container and main.

"We've been looking for the enemy for some time now. We've finally found him. We're surrounded. That simplifies things." CP

[billvon 2,478]

Choose a reserve you can land anywhere under bad conditions (i.e. in a back yard, or crosswind on a road.) If you have an AAD, choose a reserve that will land you survivably if you are unconscious.

Choose a main that you can land safely under the same sort of bad conditions - and that you can land safely even if someone cuts you off, or you misread the windsock, or there's a sudden obstacle in the landing area.

Pretty straightforward really. "Compatibility" between the main and reserve is a non-issue; most people will never see a two-out. and even if you do, tests have shown that even dissimilar canopies fly OK together.

[darkwing 4]

I agree with the "worst case" philosophy--the reserve is the right size if you can survive a landing when you are unconscious without too much damage. Generally speaking that means loading no more than, say 1.3, preferably less.

-- Jeff
My Skydiving History

[CMiller 1]

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Pretty straightforward really. "Compatibility" between the main and reserve is a non-issue; most people will never see a two-out. and even if you do, tests have shown that even dissimilar canopies fly OK together.

Why then, would anybody choose to jump a small reserve, like a 106?

[justinb138 0]

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Pretty straightforward really. "Compatibility" between the main and reserve is a non-issue; most people will never see a two-out. and even if you do, tests have shown that even dissimilar canopies fly OK together.

Why then, would anybody choose to jump a small reserve, like a 106?

Smaller container.

[riggerrob 563]

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Pretty straightforward really. "Compatibility" between the main and reserve is a non-issue; most people will never see a two-out. and even if you do, tests have shown that even dissimilar canopies fly OK together.

Why then, would anybody choose to jump a small reserve, like a 106?

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

The 106 reserve fits into a smaller container, which makes their ass ... er ... testicles look bigger.
Har!
Har!
Har!

[riggerrob 563]

Back when I started jumping - late 1970s - a 220 square foot, 7-cell main was the fashion and few guys wanted to jump a reserve much smaller than a 180 square foot, 5-cell.
That logic survived even though fashionable mains got smaller and smaller until reserve sizes got obscenely tiny.
Few skydivers understand how much main and reserve technology have diverged since the mid 1980s. So there are a lot of skydivers wearing reserves way too tiny for survivable landings, because they just don't understand the difference in flare characteristics between an elliptical, 21-cell, ZP main and a rectangular, 7-cell, F-111 reserve.

As for how size differences affect two-outs ... During a biplane, the smaller reserve usually gracefully follows the main.
Side-by-sides with dis-similar canopies will turn, with the speed determined by the difference in size.
Down planes with dis-similar-sized canopies are just plain scary!

[kkeenan 13]

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Why then, would anybody choose to jump a small reserve, like a 106?

In case you have not encountered this principle already, let me introduce it to you:

"Some skydivers are not particularly smart, and will make decisions based on reasons that defy logic."

I doubt that anyone of avarage size who lands a 106 reserve in a tight neighborhood following an emergency would continue to jump that reserve.

Kevin K.

_____________________________________
Dude, you are so awesome...
Can I be on your ash jump ?

[phoenixlpr 0]

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I doubt that anyone of avarage size who lands a 106 reserve in a tight neighborhood following an emergency would continue to jump that reserve.

Some goes for main, desn't it?

[CMiller 1]

So a reserve larger than the main is the safest thing?

[dragon2 0]

Just get both a main and a reserve that you can safely land anywhere.

ciel bleu,
Saskia

[Reginald 0]

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Pretty straightforward really. "Compatibility" between the main and reserve is a non-issue; most people will never see a two-out. and even if you do, tests have shown that even dissimilar canopies fly OK together.

Bill, which tests are these? I'd like to review the info. This is a topic of much debate so I'd like to get more info.

"We've been looking for the enemy for some time now. We've finally found him. We're surrounded. That simplifies things." CP

[kkeenan 13]

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Some goes for main, desn't it?

Sort of. It's just that with a reserve, you are usually open lower, limiting your time to set up approaches, and you have probably just dealt with an emergency, which may have left you injured and/or disoriented. This all makes it more important to have a canopy that is reliable and conservative.

Kevin

_____________________________________
Dude, you are so awesome...
Can I be on your ash jump ?

[ryoder 1,412]

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Why then, would anybody choose to jump a small reserve, like a 106?

Because of the lemming mentality that has afflicted skydiving for as long as I've been involved. Read this:

http://www.dropzone.com/cgi-bin/safety/detail_page.cgi?ID=19

Long ago I actually had a jumper threaten to punch me because I had the audacity to wear a rigid helmet on an RW jump that had funneled. You see, wearing hard helmets wasn't "cool" at that point in time, and the justification was that it might hurt someone else.

"There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones.

[phoenixlpr 0]

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Sort of. It's just that with a reserve, you are usually open lower, limiting your time to set up approaches, and you have probably just dealt with an emergency, which may have left you injured and/or disoriented. This all makes it more important to have a canopy that is reliable and conservative.

It comes without saying.

[billvon 2,478]

>Why then, would anybody choose to jump a small reserve, like a 106?

1) They have a 97 square foot main, and the container they chose require the main and the reserve to be similar sizes. (A problem with many container companies.)

2) Smaller rigs are cooler.

3) Small mains are cool and therefore small reserves must be cool too.

1) and 2) may be ameliorated by the new PD low-bulk reserves. It will allow a small main and reserve container with a significantly larger reserve than fits now.

[riggerrob 563]

1) and 2) may be ameliorated by the new PD low-bulk reserves. It will allow a small main and reserve container with a significantly larger reserve than fits now.

[grue 1]

I've got a 190 square foot main and a 220 square foot reserve. I am exceedingly uncool

cavete terrae.

[fcajump 156]

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So a reserve larger than the main is the safest thing?

Not necessarily...

I agree, get the reserve you will want over your head after getting knocked silly, breaking an arm and/or opening low over a tight neighborhood with no outs.

Get the main that is appropriate to your skill level and type of flight you do (swoop v/s demo etc...)

Get an AAD! (hey, its my opinion here... not necessarily yours )

Get a container appropriate to the reserve and main selected and a harness that FITS YOUR BOD and is appropriate to your type of jumping (freefly, sit, etc).

Review the studies concerning double deployments and use the knowledge to choose the most compatible canopies within the sizes you picked (above). And re-read them to prepare yourself for "what-if" based on the actual canopies you have on your back.

Just my $.02
JW

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

[winsor 192]

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I've heard that it's dangerous to jump a reserve much smaller than the main (or is it vice versa). Should the reserve be smaller, or bigger? If so, by how much?

What exactly is the danger of having the two canopies be significantly different sizes?

How do you determine what size reserve you should have if you know the size of your main?

My approach is to get the biggest reserve I can, regardless of the size of the main. I am partial to the Raven II, but have reserves that are much larger.

My first square reserve was 175 sq. ft. I have put a couple of rides on it, and it worked fine. It is, however, the smallest reserve I have had to date.

I have two rigs with 99 mains and 218 reserves (and others with less drastic a difference between the two).

I have not had occasion to do personal CRW, and do not plan for that eventuality to any great extent. I will work it out if and when it ever happens.

I have, however, been under a reserve enough times to have a strong opinion on the matter. When I yank silver, I want a nylon overcast to result.

I consider a reserve on its own merits, and do not give much consideration to the size of the main.

A good rule of thumb is to size a reserve like you would size a BASE canopy. Being able to land in full control in very tight spaces, with no outs, after opening low is a pretty good set of characteristics to have when you use your last option. BASE jumpers don't tend to load heavily; 0.7 pounds per square foot is about par.

I have never heard someone land after a reserve ride saying that they intended to downsize their reserve.

There may be some benefit to having a high-performance reserve, but I have no idea what it might be. Considering the pitfalls of a tiny reserve, I am not too curious what might be the up side.


Blue skies,

Winsor

[flipper 0]

Was affected by No 1 ....They have a 97 square foot main, and the container they chose require the main and the reserve to be similar sizes. (A problem with many container companies.)

Ended up under a smart 99 after the main spun up.
Deployment, flight & landing were problem free but I reckon that getting as big as you can is the way ahead

Flipper

[jimmytavino 16]

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I've got a 190 square foot main and a 220 square foot reserve. I am exceedingly uncool

.... hey well then i am MORE Uncool
than grue....cause my main is a 210 (spectre)
and my reserve is 225... soo i am 25 square feet MORE uncool, than grue. whoo hoo
and cmiller............. it has to do with wingloading, and the idea that your canopies should suit your body size...
( I prefer a WL near 1:1........for any canopy I fly ) . and i'm ok with a larger sized harness/container system....
a smaller person could naturally fly smaller sized canopies... as long as the resultant wingloading does not get tooooo extreme....
landing on the DZ on a well mowed lawn is waaay different than an off field landing, 'who knows where'....... good question.
jmy