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I understand your feelings, though I disagree with the logic. If you would like to discuss this further we can do it in some other venue (at least not this thread). Regards, Alexander. http://staticlineinteractive.com

The short answer is: the model is not perfect. The longer answer is, that there are multiple variables at play and the model must accommodate the steady state as well as the response to the inputs. This requires a compromise which results in parameters that produce overall behavior. By definition it is a mathematical approximation of the reality. As the model becomes better we'll see better results. In general, the goal of the simulator is to support the discussions such as this one. I was happy to see that it was brought up in the conversation. Regards, Alexander. http://staticlineinteractive.com

In a steady state flight, when nothing changes, there should be no affect of wind speed on descent rate. This is only true if nothing changes at all. At the same time, air density and temperature changes with altitude and these will act as changing inputs. It helps to think about the parachute and skydiver as two bodies. These bodies have different momentum (different mass) and different drag. When both bodies get the same additional input, their relative speed changes differently and this causes the canopy to surge forward or the skydiver to swing forward. This is similar to what is happening when we apply inputs to the canopy. These changes will affect angle of attack, which will affect lift coefficient and therefore the descent rate. I understand that this formula is for a fixed wing aircraft, but the principle still applies. See above. Gusts affect landings because they cause change in angle of attack more than they affect lift. Think of two bodies with different masses getting the same impulse applied to them. Thanks to Sinisa for letting me know about this discussion. Regards, Alexander. http://staticlineinteractive.com

I am the developer of the skydiving simulator for static line interactive. I am away from good Internet access right now. I will read the thread once I am back early next week. Alexander Regards, Alexander. http://staticlineinteractive.com

I'd love to come. I wrote Terry a few emails, but no response yet :( Regards, Alexander. http://staticlineinteractive.com

It seems that you have a good laptop, but the video card does not support all the features of the program. But it seems that you get it to work, which is good. Full version of the program has an option which allows you to have good landing all the times. This option is useful for practicing the pattern only :) Regards, Alexander. http://staticlineinteractive.com

I did not know there is AFF for round parachutes :) Regards, Alexander. http://staticlineinteractive.com

If the computer meets minimum specs for the game, then there is something funky going on. Could you send me more information? Regards, Alexander. http://staticlineinteractive.com

What do you think about giving a skydiving computer game as a Christmas present? For example, Force Field Accuracy for PC? Blue skies. Alexander.

That is exactly why there are so many simulators and other skydiving related software. First it must be economic to produce a product at all. Regards, Alexander. http://staticlineinteractive.com

Of course. Before you install the new version, make sure you know your serial number (it was in the email you get when you purchased the software, or you can find it by starting the program and clicking Help and selecting About page). Uninstall the previous version. Install new version. Enter your serial number. You are all set. Let me know if you have any difficulties. Regards, Alexander. http://staticlineinteractive.com

Hello, Landing Pattern 1.4 is released. Landing Pattern is designed to help the understanding of how different wind conditions affect the landing approach. Now it is possible to design and add your own virtual dropzone. There are video tutorials and step by step instructions. Check it out. Blue skies. Regards, Alexander. http://staticlineinteractive.com

FAQ thread has some answers about this issue. Regards, Alexander. http://staticlineinteractive.com

Hello, Landing Pattern 1.2 is released. Landing Pattern is designed to help the understanding of how different wind conditions affect the landing approach. Check it out. Blue skies. Regards, Alexander. http://staticlineinteractive.com

Hence this pattern should not be exercised. But if you are to land in the experience landing area, you'd have to use a different pattern. We live it up to students to see what each pattern is and they should discuss it with their instructors to figure out which one is good for them :) I believe in general it is not recommended to cross the runway under 1000ft, which means the whole pattern must be done on one side or the other. Regards, Alexander. http://staticlineinteractive.com

That is the perfect question. Short answer: no one will tell you. It is not given in the canopy specifications. You can find it (approximately) by jumping with a gps and analyzing the recorded track. It's commonly said that student canopies have glide ratio of 3 (in no wind conditions). The speed somewhere under 20mph. But these numbers depend on the wing loading, air density, canopy material, etc. In either case it does not matter, because you can not get the exact values for the constantly changing conditions. You can use trackingdurby.com to look at the gps tracks of people who jump with a similar canopy to get approximate results. Notice, thought, that recordings are done in a windy situation. And the direction and strength of the wind is not known. This is why it is important to understand how to modify your pattern based on the conditions. This is what the estimator can help you with. There is also Landing Pattern simulator that helps to actually see how to fly the pattern. Regards, Alexander. http://staticlineinteractive.com

People often confuse the distinction between different types of aids. You can roughly separate all aids into two categories: 1) used before the jump; 2) used during the jump. They should not be compared to each other, unless you are good comparing oranges with apples. Now you are saying it. You do have to learn... and there is a finite number of ways to learn. Some ways are more efficient than the others. Literature on learning methods have these things covered for us :) Regards, Alexander. http://staticlineinteractive.com

Static Line Interactive has real time computer canopy simulators that can be helpful in understanding of canopy controls (how inputs change canopy glide, how to fly landing approach, etc...) This is our answer to flight simulators for airplane pilots. http://staticlineinteractive.com/ Regards, Alexander. http://staticlineinteractive.com

Let's take away flight simulators from airpline pilots as well, just in case. Thanks Andy9o8, you said it! "sussed it" means "figured it out", I also did not know that one. The day was not spent in vain, I've learned something new, thanks shropshire. Regards, Alexander. http://staticlineinteractive.com

Google satellite map is overlay with lines to show the downwind, base and final legs of the landing approach. You can change wind strength and direction, speed of the canopy, glide ratio of the canopy and see how it changes the landing pattern. [url http://staticlineinteractive.com/ApproachEstimator.php]http://staticlineinteractive.com/ApproachEstimator.php[url] Regards, Alexander. http://staticlineinteractive.com

Hello, Eagleeye. When you register you are asked how old you are. http://staticlineinteractive.com/phpBB3/faq.php#f07 You've pressed the wrong button. The contact information can be found here: http://staticlineinteractive.com/contact.html Send your account name and they will activate it for you. Blue skies. Regards, Alexander. http://staticlineinteractive.com

I'm confused about "increased horizontal component of lift across the entire wing" and how roll affects it. It's clear that roll affects the direction of the lift. Lift can be affected by velocity of the relative wind, angle of attack, area of the wing (the rest are parameters are properties which stay constant with or without roll, I think). So for lift to change, roll must change some of these. I can see that as the roll increases the lift drops down, because wind does not move along the surface of the wing, but across it. This means horizontal component should decrease as well. What am I missing in the rolling action? I can understand the tilt of the lift, due to the change of the trim on one side of the canopy. My confusion can be explained as following: imagine that the canopy has lifts straight up (let's imagine it) as I pull left front riser I can see that the left side lift tilts forward, which should create a motion down and forward relative to the other side, given that the magnitude of the lift stays the same. Well this means that the right hand turn should happen. But we all know it does not. So my understanding of tilt is wrong in one (or all) of the following: it tilts the other way (hard to connect with the trim change, though), the magnitude of the lift changes to make sure that horizontal component is less than of the other side (most likely, but I do not see increase in the horizontal component). Of course once in the turn, the speed increases including horizontal component, but I'm trying to understand the transition. Thanks. Regards, Alexander. http://staticlineinteractive.com

Given that the "roll" happens towards the input side, then vertical (perpendicular to the canopy surface) component of the lift should go down, hence the side drops down creating "roll". This roll helps sliding of the canopy to the side. That's clear. In order for the "roll" to happen increase angle of attack should reduce lift coefficient enough to compensate for the increased speed of the side. This says that the lift coefficient curve must have a decline steeper than quadratic (lift changes depends on the square of the speed). What side of the canopy has increased horizontal component of lift? It looks to me, as drudchen said, the input side must experience the drop in horizontal component, so that yaw can happen in the correct direction. Thanks. Regards, Alexander. http://staticlineinteractive.com

Hello, The common explanation for a toggle turn is that one side of the canopy slows down while the other maintains the speed. The result is that the faster side goes around the slower one. So left toggle down -> left side is slow -> left turn happens. Trying to use the same logic for front risers results in the confusion for me. Front risers increase the speed of the canopy. So pulling down left front riser should increase the speed of the left side, so the RIGHT turn should happen. It does not :) What am I missing there? Thanks. Regards, Alexander. http://staticlineinteractive.com

It's possible to use SLI forums to find more information or ask for help. Regards, Alexander. http://staticlineinteractive.com