andyturner 0 #1 June 22, 2009 Hi, What’s the score with Line Trims? I here people talk about Rotation trim, Sequential trim, “World record” trim and Demo trim!!!! I’ve had a look on the web and on PD’s website and I’m hazarding a guess so please feel free to shoot me down in flames if I’ve got it wrong! World Record is just PD’s standard “Competition trim”. PD offer 2 main trims, Competition and Demo. For Demo PD don’t specify lengths – are they longer/shorter/angled & why? For competition PD offer “Standard” and “Short”. I’m guessing that “Short” is for Rotations because being shorter the canopy is more solid and there is slightly less distance to cover in the air if the stack are using shorter lines. The “Standard” competition line trim is used for Sequential work. Apart from these there are no other odd little quirky custom line trims that I don’t know about??? Cheers, Andy PS. I need to know this info because I’m looking for a second hand 176. Quote Share this post Link to post Share on other sites
crwslut 0 #2 June 22, 2009 Hi Andy. World Record trim/Sequential trim is what you want. That is what most of us are using, and it will keep you compatible, especially if you embrace CF fully, excel, and then want to use your canopy on the next world record! What could possibly go wrong? Quote Share this post Link to post Share on other sites
andyturner 0 #3 June 22, 2009 Quote Hi Andy. World Record trim/Competition/Rotation trim is what you want. That is what most of us are using, and it will keep you compatible, especially if you embrace CF fully, excel, and then want to use your canopy on the next world record! Hi CRWSlut, its my understanding that... 1. Sequential is the standard PD comp line trim and exactly the same as World record 2. Rotation is just the short version of Sequential. please correct me if i'm wrong. Rest assured I usually am :0) Best regards Andy Quote Share this post Link to post Share on other sites
crwslut 0 #4 June 22, 2009 You are correct. I (and my previous post) stand corrected. Here's the straight dope from cfworldrecord.com: "PD's Sequential line set trim: Line lengths for the given sizes are listed in the chart below. Canopy Line Size Length (feet) 113 8 126 8 1/2 143 9 160 9 1/2 176 10 193 10 1/2 218 11 "What could possibly go wrong? Quote Share this post Link to post Share on other sites
VectorBoy 0 #5 June 23, 2009 Most of the newer lightnings have the world record trim. We even had our rotation team canopys relined with it. Quote Share this post Link to post Share on other sites
relyon 0 #6 June 23, 2009 Line length and trim are closely related but are distinctly different things. Line length is just that and it assigns the length of the A lines. Length effects the formation plane/stack height, "reactivity" (somewhat subjective), and recovery arc length, among other things (*). Line trim is the difference in length of each additional line (front to back: B, C, D, brakes, etc). Trim sets how "steep" a canopy is and effectively sets the rate of descent with no input, among other things. Lightning trims are ordered sequential, rotation, and demo from "flatter" to "steeper" (**). Sequential was the first trim and rotation has added later (ostensibly for rotation use and necessitating the name sequential for the original trim). Demo came even later in combination ZP upper skin/F111 lower skin canopies where CRW was done during the later stages of a combined RW/CRW demonstration jump (***). See the attached for more details. Bob * Shorter lines do Stalled Canopy Relative Work (SCReW) better than longer ones; "World Record" line lengths don't SCReW worth a damn ... ** A "flatter" trim has less of an angle between nose-tail-horizon than a "steeper" one does. *** IIRC, the late Jerry McCauley worked with PD to develop/test demo trim in conjunction with his duties as a Navy Leap Frogs team member. Quote Share this post Link to post Share on other sites