Jun 25, 2001, 12:11 PM
Post #1 of 19
Smaller Canopy Issues
After <A HREF="http://www.dropzone.com/cgi-bin/forums/showflat.pl?Cat=&Board=forumtalkback&Number=18911&page=&view=&sb=&vc=1" target="_new">my last jump</A> my JM said he was gonna put me under a smaller canopy... a PD 230 instead of a PD 280.
I am 198 lbs out the door, giving me a wing loading of .71 using the PD 280.
My wing loading becomes .86 with the PD 230.
How different will it be? What can I expect? .86 wing loading is still pretty docile, right?
I recently switched from a Manta 290 (ZP) to a PD 230 (F-111), changing wingloadings from 0.8 to 1.0. I noticed more forward drive and a little faster descent but nothing that put me in danger or felt out of control.
I read somewhere that pulling slightly on the front risers will also give me better wind penetration. True?
Based on my experiences on my canopy... yes and no. When I front riser, my forward speed increases, but so does my rate of descent. So, I'm going forward faster, but my glide path actually gets steeper. So if I were safely over my target area, but blowing backwards, using the front riser will keep me from backing up as much, or even allow me to get some penetration. On the other hand, if I'm already making some penetration and I front riser, I'll end up landing shorter than I would if I flew without them because of the steeper angle of descent. These are my results on my canopy, so your milage may vary depending on your wing-loading, type of canopy, etc.
Remember you'll also pick up more speed when you're front risering, so remember to let up a safe distance above the ground before you flare and always keep your toggles in your hands while doing it.
I read somewhere that pulling slightly on the front risers will also give me better wind penetration
I had better luck getting back from a bad spot under a PD190 (loaded about like you will load a 230) by going into quarter brakes and pulling my legs up. Front risering will give you more forward speed but the speed comes from the canopy diving (=faster rate of descent). By hanging in 1/4 brakes you are allowing the canopy to develop more lift (slower rate of descent) than at full flight without reducing your forward speed too much. Pulling the legs up reduces your "parasitic drag" a bit - probably not necessary, but with some of the spots we used to get and that nasty farmer across the road every little bit helped!
Anyone correct me if I'm wrong, but I think the best way to get back from a long spot is to release the brakes (this makes you canopy fly at its most efficeient) and then pull on the rear risers.
This should be more efficient then just pulling the breaks as you alter more of the canopy glide angle (you actually drop the full rear 1/2 of it, as opposed to just the trailing edge if you just use brakes).
But it is much harder on the arms.... ouch
I can cover more distance this way under my Stiletto 170 loaded at 1.5 (yes, I'm fat...) then my wife under her Tri 120 loaded at 1.25 even when she flies in 1/4 brakes.
I think the best way to get back from a long spot is to release the brakes and then pull on the rear risers
This is how I have always understood things. Using the brakes reduces the efficiency, killing lift, increasing fall.
The other thing that you can do is use the front risers to gain speed, to get you better penetration, but you sacrifice altitude. You have to decide the trade-offs. Mainly, you would need the speed if you are in high wind but near the landing area, and distance if you are far from it. If you are far and there is a lot of wind, well, seek an alternate. No amount of jiggling the risers can overcome the laws of physics.
I was told that quarter brakes is more efficient than full flight and my own "experimentation" (i.e. who let that guy spot again??) seemed to bear this up.
Easy way to find out for sure for yourself is to go out with a friend flying an equally loaded, equivalent canopy - have him/her fly alongside you at full flight, you go into quarter brakes. See who gets the most distance across the ground.
Nice try on the sponsored research, but I'm afraid it's alresdy been done (!) By glider pilots.
The information IS out there (somewhere... can't remember where) but it's a factor of increased sink rate & consequent penetration against wind speed & direction. Glider Pilots have actually had it reduced to mathematical equations and graphs! This conclusively proves that they need to get out more!
Anyway, short version (for us) is if you're travelling forward, or with the wind, reduce sink rate (back riser). Moving into wind increase penetration (front riser). When you land out, remember to smile sweetly at the farmer and he MIGHT give you a lift back to the DZ!
I could cover much more ground with my old 107 stiletto in brakes then I could with rear risers.(with the wind) I have took it on cross countries as far as 16 miles from 9000' I have spent a lot of time flying brakes and rear risers and I feel that brakes are the best upwind. J
Hey GeekStreak While I would never presume to dispute the experts, I will tell you I have found that a 1.1 and even a 1.2 wing loading are very docile.
My story I made about 96 jumps in early 70's about 70 or so on rounds then about 20-25 on square's. I did not jump again until this year. I was put out on a Manta 288 (what a dog) I made two jumps on it, then two on a Falcon 265. They were both so bad I bought my own gear. I then jumped a Triathlon 175, it was great. It was docile, turns were better, the flare was so much better and landings were suddenly stand up. I load this canopy at a 1.2 I'm 210 out the door. It was so much better then them big old manta's and falcon's. I really think they should do away with all that big stuff and start students out on something more in the 210 range. But then I can only say what worked for me and moving down in the 1+ wing load range helped a bunch. I wouldn't worry about being under a 1.0 wing load it should be pretty docile.
Some fun eh!
Jul 6, 2001, 2:51 AM
Post #18 of 19