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On wingloading is it better to be on the .8 side or on the .65 side and what is the difference from them? like little more gives you all little more speed which in turn would give you more lift or does a .8 give you more off heading or on heading. i'm 220lbs and losing more weight looking to be 200 to 190 by june going to norway but do not want to jump my 310 blackjack want to buy a 310 ace or 280 ace and for the wingloading its looking like 280 .78 at 210 to 220 gear and all or .7 with a 310, I have talked to a few friends and one said 310 the other said 280 so would like to know what others think.


Thanks B

I would go with the 280. But that being said it would depend on what you jump and where the most. There is nothing wrong with the 310 loaded at .7 if your jumping objects that require little to no wind. But like here in the midwest where antennas are your primary objects and you can safely jump in higher winds you will find yourself going backwards in less than 10 mph winds or less. You can not compare a smaller canopy with a wingloading at .7 with the 310 at .7. The sheer drag of the canopy does not scale with wingloading. I myself use to own a BJ 310 and lost 25 lbs which put me a .69. Places like Moab it was great but at home it sucked. I now load my BJ 280's at .77 and jump with another guy who loads his BJ 280 at .8. Perfect!! Even Adam recommends a higher wingloading on the 280's and larger. I have to agree.

Only my opinion
BASE 772

A few things that I would like to offer my opinion on in your post.
Primary: .
That seems to be quite a challenge for a lot of people (20lbs in 5 months).
http://www.calorie-count.com/forums/post/48821.html
That will take some dedication. Respect!
Secondary: Not in the instance you speak of. If you fly your present canopy with more speed, you would theoretically produce more lift (Lift Thrust). If you downsize, The canopy will have to fly faster to produce enough lift thrust to support you, but due to the fact that, You, the pilot, have the same surface area/ weight and the wingloading has increased, so in effect you have increased the ratio of the drag to the lift. What this means is that the canopy's slowest flying speed is now faster than the one with a lesser wingloading. Whether for landing or for opening facing the object.
A common misconception is that "high performance" means a higher wingloading. High performance means that a canopy can fly slower than a comparable canopy.
It means that the canopy can produce the same amount of lift at a slower speed. I prefer the phrase "more efficient airfoil".
Tertiary: hmmmmm. I think that one would get the same amount of off headings from both. I prefer to pretend that I will have more off headings with a different canopy than that I am most used to. Helps me make a better decision at the exit point.

My experience in Lysebotn, Norway was that a bigger canopy was better, landing areas can be challenging. Slower is better IMHO. On the windy days, backing it up to the chosen LZ was not a prob for me. Landing in no wind on the shoreline was only a small challenge.
At times that I jumped a higher wing loading, landing in low or no wind conditions were quite challenging.
Hope this helps,
Take care,
space

If you're doing most of your jumping near home (Arizona), I'd recommend going with the larger size (310).

With bottom skin inlets, I don't think the size or wingloading will make any difference to opening heading.

Why don't you want to jump the Blackjack?

If you're going to keep the Blackjack, I'd go with a 280 Ace, so that you'll have both in the inventory, and can take the Blackjack out on the slider down cliffs near home, but use the smaller Ace on the big cliffs (or potentially windy antennas).

Are you calculating the rig too? Currently I jump a BJ 260, Ace 260, and a fox 265 (ONLY slder up with softer type landing areas, it is old) and I weigh 185 withOUT gear. I have found that with those setups in ALL arenas of BASE Ive been good, lucky maybe, but good. I jump from may till late september in HIGH winds, which I like a HEAVIER wing loading. other times of the year almost nill. I wish i could afford 3 summer rigs and 3 winter rigs but c'mon, lets be reasonable. IMO anything in the range of .7-.8 should be fine IF you have the canopy skills to prove it. If you dont, you shouldn't be jumpin.

nic

Thanks for all the help. however, I see that I need to tell the whole story. I work in Iraq and intend on losing 20lbs from the heat. It gets 130F here and last summer I lost 30lbs in 4 months. I'm interested in an ACE Canopy because I took my 310bj on 4 8-10 second delay jumps and was getting hit really hard. I had an off heading and it opened so hard it threw me into a line twist and knocked the breath out of me. It's not fun trying to kick out of line twist when you can't breathe. Thank god there was no cliffs to hit. Now the blackjack, I love the slider off or down and will still use it for slider off but I want to jump bigger delays so I want to build a rig for that. In short, I will be home in march to skyjump the new ace and to track in my track-suit, but I need to order or buy the ace now to be there in march. The second rig will be for slider up but i will jump it on some slider downs so i'm just looking at what would be best to get a small 280 or a 310 but would like to get a non vented canopy to go with my vented 310.

Thanks B

Hey B! I hope you're staying safe out there!

I'd recommend you stay with the bigger canopy, lower wing loading. Slower is usually better around the big rocks and hopefully you're not going to be jumping big walls in howling winds!

Keep your head on a swivel and send pics!

.65 if you're jumping smaller landing areas noting that a big landing area can become small ones when you land out because you opened low or underestimated the winds at lower altitudes. Take your pick otherwise.

I've jumped my Fox 245 & Dagger 244 from 160 (145 pounds + BASE rig) to 195 pounds off objects and up to 205 (175 + J7) out of planes. The lower wing loading is definitely preferable since it gives you a softer landing in a full sink which is real nice when things get tight.

Responsiveness isn't too different; changing canopies is needed to get big differences.

Forward speed isn't a real issue since it scales with the square root of wing loading. Going from .65 to .8 only yields an 11% speed increase or keeps you moving forward in winds that are about 2.5 MPH faster. If you want more wind penetration you'd probably be better off with a flatter trim than smaller canopy.

I've heard this before - BlackJacks do appear to open hard. Just to put it out there, another option would be to consider a different vented canopy, such as Atair's Troll, which will open more comfortably than your experience with the BJ (but not slowly!)

FYI, I've seen many people jumping vented Trolls at the ITW and in Switzerland without issues. They are sized bigger than you're used to: Troll 245 ~ Blackjack 260 etc, but most people seem to keep the same wingloading.

I´m using 0.55-0.6 WL and i like it. slow but safe. if you have problems, problem is also slow...you dont have to jump in bad wind, but problem doesnt take a place....why dig blood from your nose with a big showel if you dont have to... ???

I would decide what canopy you would prefer in the worst possible scenario and go with that one. Remember that even in Norway you could fuck up and need to land some where up on the talus and not on the sweet grass of the landing area.