Fledgling 0 #101 January 16, 2008 It could be a variety of things. Most likely the fact that some canopies simply out perform others regardless of wingloading. I also believe a lot of people fool themselves in to seeing the results that they are expecting regardless of what is going on. Quote Share this post Link to post Share on other sites
Pulse 0 #102 January 17, 2008 When talking about 'feeling uncomfortable' it really could be any number of things. You can go up on the same day, same conditions, same canopy three times and have three different experiences. Turbulence isn't particularly predictable. It could also be that you felt more comfortable under the 150 because you had already been there. Who knows?"Any language where the unassuming word fly signifies an annoying insect, a means of travel, and a critical part of a gentleman's apparel is clearly asking to be mangled." Quote Share this post Link to post Share on other sites
rhys 0 #103 January 18, 2008 Quote why did I feel so uncomfortable on my 170 zp Cayenee in windy turbulent day, and much better on the next jump on Sa2 150? Correct me if I am wrong? but a sabre2 is slighty tapered/elliptical and a ZP exe is as squre as you can possibly get. Tapered canopies have much better penetration than squares. also 'I believe' more loading = more stability. but I only have 4500 jumps"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix Quote Share this post Link to post Share on other sites
billvon 2,991 #104 January 18, 2008 >Tapered canopies have much better penetration than squares. Penetration equals forward speed. My old Nova 150 (square) has significantly better penetration than my Silhouette 170 (tapered.) It is also much less stable in turbulence. Quote Share this post Link to post Share on other sites
Pulse 0 #105 January 18, 2008 Wha? I think the extra forward speed is coming from something other than being elliptical. That doesn't do anything for speed."Any language where the unassuming word fly signifies an annoying insect, a means of travel, and a critical part of a gentleman's apparel is clearly asking to be mangled." Quote Share this post Link to post Share on other sites
rhys 0 #106 January 18, 2008 QuoteI think the extra forward speed is coming from something other than being elliptical. That doesn't do anything for speed. Elliptical canopies have smaller wing tip vortaces. wing tip vortaces = drag more drag = less penetration. true?"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix Quote Share this post Link to post Share on other sites
rhys 0 #107 January 18, 2008 QuotePenetration equals forward speed. The nova would have better penetration due to a signoficantly less percentage of surface area. = higher wing loading the Silhouette would be more stable in turbulance as it is tapered = less drag. No?"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix Quote Share this post Link to post Share on other sites
bclark 0 #108 January 18, 2008 Did the Nova not have a reputation as an unstable canopy in general? Some people have told me that they loved their Nova's. But were they not pulled off the market after several fatal canopy collapses? Quote Share this post Link to post Share on other sites
rhys 0 #109 January 18, 2008 QuoteDid the Nova not have a reputation as an unstable canopy in general? I have no experience whatsoever with the Nova. I was purely going on the information that bill had offered."When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix Quote Share this post Link to post Share on other sites
rhys 0 #110 January 18, 2008 QuoteThe "rigid wing that slices through turbulence" is largely a myth, akin to the "if you're going fast enough when you hit a pothole you won't feel it" myth. Hey bill check out the poll in the swooping and canopy piloting forum. you may be surprised of the results. And as for your pothole theory, Go on Safari to the Serengeti in Tanzania. Across the Serengeti plain the ruts and potholes are phenomenal. Guess how fast they drive there.... crazy fast. I know the owner of one of the largest safari companies and she tells her drivers to go fast. the guys that drive slow create more damage to the vehicles than the fast drivers. She has well over 50 vehicles (toyota 4x4), she would have done the maths. It is much smoother driving at 100kmph than it is at 50kmph. Interesting isn't it"When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix Quote Share this post Link to post Share on other sites
Pulse 0 #111 January 19, 2008 Quote[ Elliptical canopies have smaller wing tip vortaces. wing tip vortaces = drag more drag = less penetration. true? True. But induced drag doesn’t affect speed so much as it does the amount of lift the wing produces. It also becomes less of an issue as speed increases. Either way, we’re talking very minimal changes. His 12% increase in wing-loading would be a much bigger factor. We seem to think that canopies are radically different from one another but they really are not. The performance range from ‘low performance’ canopies to ‘high performance’ canopies is probably the smallest range found anywhere in aviation."Any language where the unassuming word fly signifies an annoying insect, a means of travel, and a critical part of a gentleman's apparel is clearly asking to be mangled." Quote Share this post Link to post Share on other sites
JanuszPS 0 #112 January 19, 2008 rhys, Correct me if Cayenne is not tapered. It is more tapered than Sa2 in fact. Go to firebird web site - former PV. Therefore I do not consider them as two different types of canopies. I do not consider Sabre as eliptical canopy, it is closer to square than eliptical. But I have 20 times less jumps than you and have broken English.Regs JanuszPS Back to Poland... back home. Quote Share this post Link to post Share on other sites
rhys 0 #113 January 19, 2008 QuoteCorrect me if Cayenne is not tapered. It is more tapered than Sa2 in fact. Oops. my mistake. I assumed it was a square. The higher wing loading would have been the defining factor then. 20 square feet is a significant size reduction."When the power of love overcomes the love of power, then the world will see peace." - 'Jimi' Hendrix Quote Share this post Link to post Share on other sites
riggerrob 643 #114 January 28, 2008 That depends upon the spacing/frequency of wash-board roads. Every wash-road road and vehicle combination has its ideal speed/frequency. IOW The "perfect speed" for a Toyota 4x4 would be miserable in a Toyota sports car. Air turbulence is far more difficult to predict. Quote Share this post Link to post Share on other sites
Liemberg 0 #115 January 28, 2008 QuoteMy old Nova 150 (square) has significantly better penetration than my Silhouette 170 (tapered.) It is also much less stable in turbulence. Have you considered that there may be something else where these two canopies differ significantly? Slight variations in angle of attack, 'curve' (i.e. 'flatness' of the wing) shape of the cell where the air gets in etcetera may all have surprising effects on inherent stability of a canopy IMHO... Furthermore: when taxiing on our not so smooth grass airfield we find that the pilots that 'pull the stick into their stomach' and 'almost take off' are significantly less 'accident prone' (prop into the ground / damage to the front wheel). On the same note as rhys his example with those 4x4's , our chief-pilot, who oversees the pilots and hires the young ones fresh from flight school, invariably teaches them to speed up to avoid damage... He seems to have his reasons and himself never has a propellor in the ground - that happens to very slow and cautious taxiing weekend pilots ... "Whoever in discussion adduces authority uses not intellect but memory." - Leonardo da Vinci A thousand words... Quote Share this post Link to post Share on other sites
billvon 2,991 #116 January 28, 2008 >Have you considered that there may be something else where these >two canopies differ significantly? >Slight variations in angle of attack, 'curve' (i.e. 'flatness' of the wing) >shape of the cell where the air gets in etcetera may all have surprising >effects on inherent stability of a canopy IMHO... Absolutely! In the case of the Nova, it was airfoil shape. It didn't matter how pressurized that canopy was or how heavily it was loaded - it was unstable. >when taxiing on our not so smooth grass airfield we find that the pilots >that 'pull the stick into their stomach' and 'almost take off' are significantly >less 'accident prone' (prop into the ground / damage to the front wheel). Also agreed, and that's pretty standard for any soft landing/takeoff procedure. I used to practice soft-field takeoffs and landings in a nearby grass field, and right after it was mowed you absolutely had to keep speed up to keep from getting bogged down - and you had to keep power up and yoke back to keep the prop clear of the piles of grass. (Of course that's a somewhat different topic.) Quote Share this post Link to post Share on other sites
moto89 0 #117 January 31, 2008 Obviously not a TI, so I could not know the answer to this question which I why I pose it. Do tandem canopies have a reputation for heavily distorting in full brakes? Correct me if I am wrong, but cross braces are designed to minimize canopy distortion during a flare to make for a more efficient wing, as opposed to one that losing a significant amount of wing area mid flare. I could see this being an advantage and providing softer landings with more lift, not necessarily monster swoops.Less talking, more flying. Quote Share this post Link to post Share on other sites
diablopilot 2 #118 January 31, 2008 Crossbracing reduces distortion of the wing from load factor.---------------------------------------------- You're not as good as you think you are. Seriously. Quote Share this post Link to post Share on other sites
moto89 0 #119 January 31, 2008 Nonetheless, could it be possible that a crossbraced tandem canopy is not made for swooping, but rather taking cutting edge ram-air parachute technology to make a more efficient wing? I'm not saying that is my opinion, as I don't think I have the experience to say, rather playing the devil's advocate or something like that.Less talking, more flying. Quote Share this post Link to post Share on other sites
diablopilot 2 #120 January 31, 2008 Yeah, I think you've got the idea. ---------------------------------------------- You're not as good as you think you are. Seriously. Quote Share this post Link to post Share on other sites
