Adrian Law
Jan 10, 2003, 01:00 AM
<p><big>Your First Time In The Dark</p></big>
<blockquote>If you read the last issue of the <a href="http://www.liftzone.com/cgi-bin/alist/jump.pl?ID=762">Dark Side</a>, you should understand what is going on down the back of the hill and basically what is involved in dynamic soaring (DS). This time I am going to try to help you get started.</blockquote>
<p><big>Learn The Easy Way</p></big>
<blockquote>Before you get near a hill, I recommend playing with a simulation. CRRCsim is one of the few that simulates DS. We already know that DS is not the most risk free flying. Even with foamies, you could be in for a lot of walking down the back of the hill to pick up the model. Therefore, what we really need is a simulator to get used to controlling the model in consecutive funny angled loops. Well, there just so happens that there is one! A guy named Mark Drela has done a really good job of designing the flight parameters. The simulation also provides good slope and thermal soaring with a fair selection of different models. My favorite is the Outrage, and the Zagi is pretty realistic.</blockquote>
<blockquote>If you go to <a href="http://Google.com">Google.com</a> and do a search on Mark Drela, you will be amazed what he's doing! Jan Kansky did the environment and the models. He is constantly working on improving it. This simulation is the most realistic there is! There is even a yahoo group to join where people can make suggestions or help with the programming. The simulation can be found in the files section.</blockquote>
<blockquote>Join the group and go to the files section. There are a number of files in there, but have a look at the <a href="http://groups.yahoo.com/group/crrcsim/files/instructions.txt">instructions.txt</a> file first, and do as it says! If you have any problems, just email the group. Bear in mind that you will need a fairly good graphics card to run this. I am using a Voodoo4 4500 with 32mb of RAM, and it runs silky smooth.</blockquote>
<blockquote>Changing settings involves editing a text file called crrcsim.cfg or the *.air file for each model. Nigel Coward designed a small program that helps do a lot of this for you. It is available from this <a href="http://groups.yahoo.com/group/crrcsim/files/Launcher/">link</a>. </blockquote>
<blockquote>The next problem is controlling the simulated model, and for this, there are several options.</blockquote>
<blockquote><ul><li>A mouse really isn't an option in realism terms, but if that is all you have, then use it!</li>
<li>A normal PC joystick is better, but far from perfect, since it only gives you two channels.</li>
<li>If you have an old (dead) transmitter lying around, you can modify it by changing the pots and running a lead out to plug for the game port. The transmitter then becomes a 2-stick joystick. This is cheap and good if you can solder, follow simple instructions, and have a spare transmitter. For more details, follow this <a href="http://www.charlesriverrc.org/articles/tools/flightsimbox.htm">link</a>.</li>
<li>Another option, that I use, is the Ripmax Interface. It plugs into the trainer port of my Futaba transmitter and then into the game port. It works with other transmitters too, and I have even modified mine to work with my MPX 3010. You just need to change the connector that plugs into the transmitter. For more details of adapting the Ripmax interface to your transmitter, go to this <a href="http://www.rc-electronics.co.uk/buddy.htm">link</a>. The Ripmax interface handles up to seven channels. Windows sees it as a normal joystick, so you can use it for your favorite games too. This interface is available from <a href="http://www.ripmax.com">Ripmax.com</a> or your local Ripmax dealer.</li>
<li>There is also Joystick Simulator Interface Module (JSIM). I didn't find this until after buying the Ripmax interface. There are several versions of this including a USB one. You can order them online from <a href="http://www.rc-electronics.co.uk">RC-Electronics</a>, though they use PayPal.</li></ul></blockquote>
<blockquote>Once you have CRRCsim running, you start up with the model pointing into wind. Just press the up arrow on your keyboard (throttle up) to get it up in the air. Use the down arrow (throttle down) to head for the beach, and then head back up to the top of the hill. Just as you get to the top of the cliff, you will notice the DS kick.</blockquote>
<p><big>Below Are A Few Screen Shots</p></big>
<p align="center"><a href="/articles/liftzone/2003/jan/ds/crrc1.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/crrc1_t.jpg" border="2"></a> <a href="/articles/liftzone/2003/jan/ds/crrc2.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/crrc2_t.jpg" border="2"></a> <a href="/articles/liftzone/2003/jan/ds/crrc3.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/crrc3_t.jpg" border="2"></a></p>
<blockquote>There is a new simulation out similar to CRRCsim called SSS (Slope Soaring Sim). It is still fairly new and in development, so it has its problems. It does things a little differently to CRRCsim. For more info, click this <a href="http://groups.yahoo.com/group/slope_soaring_sim/">link</a>. </blockquote>
<p><big>Finding The Hill</p></big>
<blockquote>There are loads of known DS sites around. <a href="http://www.dynamic-soaring.co.uk">Dynamic Soaring.co.uk</a> lists most of the known ones in the UK. Have a look at the pictures and the maps. They should give you an idea of what you are looking for in a DS site. If you have details of sites from any part of the world, forward them to me and I will add them to the site listing.</blockquote>
<blockquote>Once you have found a good flying location, find a day that it could be working. You need to make sure the conditions are right. The first step is to walk down the back of the hill about 30 to 40 feet. The air should be completely still or blowing up from the "wrong" direction. The important thing is that it is constant, if it is blowing from all directions at different times, then the flow is not breaking away cleanly, and you are looking at some bumpy or even non-existent DS.</blockquote>
<p><big>Model Choice</p></big>
<p align="center"><a href="/articles/liftzone/2003/jan/ds/dscf0011.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/dscf0011_t.jpg" border="2"></a> <a href="/articles/liftzone/2003/jan/ds/dscf0012.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/dscf0012_t.jpg" border="2"></a></p>
<blockquote>Once you have a site that works, you know basically what DS is and how it works, and have messed with one of the simulations, then you are ready to fly, or are you? If you only have a gentle lady, then you aren't ready! Foamies are the best way to start. If something doesn't go well during your attempt, then you aren't going to break anything major. You can use any combat foamie at the right site, but they tend to be a bit draggy when you use the amounts of elevator needed to get round the circuits that some DS sites require. However, there are foamies designed for DS. They make better front side models than combat foamies too, as they tend to be more efficient, faster, and turn better.</blockquote>
<p align="center"><a href="/articles/liftzone/2003/jan/ds/dscf0017.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/dscf0017_t.jpg" border="2"></a> <a href="/articles/liftzone/2003/jan/ds/dscf0018.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/dscf0018_t.jpg" border="2"></a></p>
<blockquote>The JW available from <a href="http://www.bowmanshobbies.com/">Bowman's Hobbies</a> is a popular choice, as is the <a href="http://www.northcountyflyingmachines.com/bluto.htm">North County Flying Machines (NCFM) Bluto</a>. If you are in the UK, however, getting these into the country will cost you over £100. Therefore, you may want to consider a Duck from Edwin Jenkins. I fly one of these, and it is great. It's faster than most combat foamies, and it stays up better and turns better. For more info on the Duck, email me or drop me a message on the forums.</blockquote>
<blockquote>Ok, now you are ready. The wind is on the hill. You have your foamy in your hand. (Why isn't it in the air?) Moreover, you have been down the backside, and it looks as if the site is working. The next step is to work out your circuit. There is no "right" circuit; it depends so much on the site and the conditions of the day. Experience will tell you exactly where the circuit should be, but I can give you some ideas of what happens when you don't have it quite right.</blockquote>
<blockquote>Your first circuit should be something along theses lines. You need to pick two points. The first one should be in the dead air. Depending on the site, this is normally 40 feet below the top of the ridge, 40 feet behind the ridge, and 30 feet to one side of where you are standing. This will be called the bottom turn point.</blockquote>
<blockquote>The second point should be 20 feet above the top of the ridge, 10 feet in front of the ridge, and 10 feet sideways from where you are standing. This will be your top turn point.</blockquote>
<blockquote>Launch the model and gain a little altitude. Fifty feet should be enough; you only need enough speed to get around the circuit once. Starting a reasonable distance away, fly your plane towards yourself and the bottom turn. On your way to the bottom turn, the model will shake and accelerate as it crosses the boundary where the moving air meets the dead air. When you get to the bottom turn point, turn, and head for the top turn. On the way up to the top turn, the model will shake and accelerate again. This time, head up and out. Practice that a few times. If it is lumped around near the bottom turn, then you need to go lower and closer to the hill, as you aren't fully crossing the boundary. Don't be afraid to go lower, it is amazing how a model can make it back up the hill in the dead air.</blockquote>
<blockquote>Once you have the hang of the half circuit, move the top turn away from you (along the top of the hill) a bit more and try continuing on from the first half to the second half of the circuit. As the model passes through the boundary, correct the roll so that when you pull, the model heads back for the bottom turn point then pull. If you get the roll wrong, you will either hit the hill or end up too high for the bottom turn.</blockquote>
<p align="center"><a href="/articles/liftzone/2003/jan/ds/dscf0013.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/dscf0013_t.jpg" border="2"></a> <a href="/articles/liftzone/2003/jan/ds/dscf0014.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/dscf0014_t.jpg" border="2"></a></p>
<blockquote>Once you have that working, then you should notice the model picking up speed. Try tightening the circuit and making it as horizontal as the conditions allow. If the circuit is more vertical, then you have to fight against gravity through the bottom turn. This means more drag and load on the airframe. </blockquote>
<blockquote>That's it for this month! If you have any questions, pop into the sailplanes section of the RC Groups forums where we have our own topic for DS. Next month I am going to show you that you don't need a massive razor back ridge to go DSing.</blockquote>
<blockquote>If you read the last issue of the <a href="http://www.liftzone.com/cgi-bin/alist/jump.pl?ID=762">Dark Side</a>, you should understand what is going on down the back of the hill and basically what is involved in dynamic soaring (DS). This time I am going to try to help you get started.</blockquote>
<p><big>Learn The Easy Way</p></big>
<blockquote>Before you get near a hill, I recommend playing with a simulation. CRRCsim is one of the few that simulates DS. We already know that DS is not the most risk free flying. Even with foamies, you could be in for a lot of walking down the back of the hill to pick up the model. Therefore, what we really need is a simulator to get used to controlling the model in consecutive funny angled loops. Well, there just so happens that there is one! A guy named Mark Drela has done a really good job of designing the flight parameters. The simulation also provides good slope and thermal soaring with a fair selection of different models. My favorite is the Outrage, and the Zagi is pretty realistic.</blockquote>
<blockquote>If you go to <a href="http://Google.com">Google.com</a> and do a search on Mark Drela, you will be amazed what he's doing! Jan Kansky did the environment and the models. He is constantly working on improving it. This simulation is the most realistic there is! There is even a yahoo group to join where people can make suggestions or help with the programming. The simulation can be found in the files section.</blockquote>
<blockquote>Join the group and go to the files section. There are a number of files in there, but have a look at the <a href="http://groups.yahoo.com/group/crrcsim/files/instructions.txt">instructions.txt</a> file first, and do as it says! If you have any problems, just email the group. Bear in mind that you will need a fairly good graphics card to run this. I am using a Voodoo4 4500 with 32mb of RAM, and it runs silky smooth.</blockquote>
<blockquote>Changing settings involves editing a text file called crrcsim.cfg or the *.air file for each model. Nigel Coward designed a small program that helps do a lot of this for you. It is available from this <a href="http://groups.yahoo.com/group/crrcsim/files/Launcher/">link</a>. </blockquote>
<blockquote>The next problem is controlling the simulated model, and for this, there are several options.</blockquote>
<blockquote><ul><li>A mouse really isn't an option in realism terms, but if that is all you have, then use it!</li>
<li>A normal PC joystick is better, but far from perfect, since it only gives you two channels.</li>
<li>If you have an old (dead) transmitter lying around, you can modify it by changing the pots and running a lead out to plug for the game port. The transmitter then becomes a 2-stick joystick. This is cheap and good if you can solder, follow simple instructions, and have a spare transmitter. For more details, follow this <a href="http://www.charlesriverrc.org/articles/tools/flightsimbox.htm">link</a>.</li>
<li>Another option, that I use, is the Ripmax Interface. It plugs into the trainer port of my Futaba transmitter and then into the game port. It works with other transmitters too, and I have even modified mine to work with my MPX 3010. You just need to change the connector that plugs into the transmitter. For more details of adapting the Ripmax interface to your transmitter, go to this <a href="http://www.rc-electronics.co.uk/buddy.htm">link</a>. The Ripmax interface handles up to seven channels. Windows sees it as a normal joystick, so you can use it for your favorite games too. This interface is available from <a href="http://www.ripmax.com">Ripmax.com</a> or your local Ripmax dealer.</li>
<li>There is also Joystick Simulator Interface Module (JSIM). I didn't find this until after buying the Ripmax interface. There are several versions of this including a USB one. You can order them online from <a href="http://www.rc-electronics.co.uk">RC-Electronics</a>, though they use PayPal.</li></ul></blockquote>
<blockquote>Once you have CRRCsim running, you start up with the model pointing into wind. Just press the up arrow on your keyboard (throttle up) to get it up in the air. Use the down arrow (throttle down) to head for the beach, and then head back up to the top of the hill. Just as you get to the top of the cliff, you will notice the DS kick.</blockquote>
<p><big>Below Are A Few Screen Shots</p></big>
<p align="center"><a href="/articles/liftzone/2003/jan/ds/crrc1.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/crrc1_t.jpg" border="2"></a> <a href="/articles/liftzone/2003/jan/ds/crrc2.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/crrc2_t.jpg" border="2"></a> <a href="/articles/liftzone/2003/jan/ds/crrc3.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/crrc3_t.jpg" border="2"></a></p>
<blockquote>There is a new simulation out similar to CRRCsim called SSS (Slope Soaring Sim). It is still fairly new and in development, so it has its problems. It does things a little differently to CRRCsim. For more info, click this <a href="http://groups.yahoo.com/group/slope_soaring_sim/">link</a>. </blockquote>
<p><big>Finding The Hill</p></big>
<blockquote>There are loads of known DS sites around. <a href="http://www.dynamic-soaring.co.uk">Dynamic Soaring.co.uk</a> lists most of the known ones in the UK. Have a look at the pictures and the maps. They should give you an idea of what you are looking for in a DS site. If you have details of sites from any part of the world, forward them to me and I will add them to the site listing.</blockquote>
<blockquote>Once you have found a good flying location, find a day that it could be working. You need to make sure the conditions are right. The first step is to walk down the back of the hill about 30 to 40 feet. The air should be completely still or blowing up from the "wrong" direction. The important thing is that it is constant, if it is blowing from all directions at different times, then the flow is not breaking away cleanly, and you are looking at some bumpy or even non-existent DS.</blockquote>
<p><big>Model Choice</p></big>
<p align="center"><a href="/articles/liftzone/2003/jan/ds/dscf0011.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/dscf0011_t.jpg" border="2"></a> <a href="/articles/liftzone/2003/jan/ds/dscf0012.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/dscf0012_t.jpg" border="2"></a></p>
<blockquote>Once you have a site that works, you know basically what DS is and how it works, and have messed with one of the simulations, then you are ready to fly, or are you? If you only have a gentle lady, then you aren't ready! Foamies are the best way to start. If something doesn't go well during your attempt, then you aren't going to break anything major. You can use any combat foamie at the right site, but they tend to be a bit draggy when you use the amounts of elevator needed to get round the circuits that some DS sites require. However, there are foamies designed for DS. They make better front side models than combat foamies too, as they tend to be more efficient, faster, and turn better.</blockquote>
<p align="center"><a href="/articles/liftzone/2003/jan/ds/dscf0017.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/dscf0017_t.jpg" border="2"></a> <a href="/articles/liftzone/2003/jan/ds/dscf0018.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/dscf0018_t.jpg" border="2"></a></p>
<blockquote>The JW available from <a href="http://www.bowmanshobbies.com/">Bowman's Hobbies</a> is a popular choice, as is the <a href="http://www.northcountyflyingmachines.com/bluto.htm">North County Flying Machines (NCFM) Bluto</a>. If you are in the UK, however, getting these into the country will cost you over £100. Therefore, you may want to consider a Duck from Edwin Jenkins. I fly one of these, and it is great. It's faster than most combat foamies, and it stays up better and turns better. For more info on the Duck, email me or drop me a message on the forums.</blockquote>
<blockquote>Ok, now you are ready. The wind is on the hill. You have your foamy in your hand. (Why isn't it in the air?) Moreover, you have been down the backside, and it looks as if the site is working. The next step is to work out your circuit. There is no "right" circuit; it depends so much on the site and the conditions of the day. Experience will tell you exactly where the circuit should be, but I can give you some ideas of what happens when you don't have it quite right.</blockquote>
<blockquote>Your first circuit should be something along theses lines. You need to pick two points. The first one should be in the dead air. Depending on the site, this is normally 40 feet below the top of the ridge, 40 feet behind the ridge, and 30 feet to one side of where you are standing. This will be called the bottom turn point.</blockquote>
<blockquote>The second point should be 20 feet above the top of the ridge, 10 feet in front of the ridge, and 10 feet sideways from where you are standing. This will be your top turn point.</blockquote>
<blockquote>Launch the model and gain a little altitude. Fifty feet should be enough; you only need enough speed to get around the circuit once. Starting a reasonable distance away, fly your plane towards yourself and the bottom turn. On your way to the bottom turn, the model will shake and accelerate as it crosses the boundary where the moving air meets the dead air. When you get to the bottom turn point, turn, and head for the top turn. On the way up to the top turn, the model will shake and accelerate again. This time, head up and out. Practice that a few times. If it is lumped around near the bottom turn, then you need to go lower and closer to the hill, as you aren't fully crossing the boundary. Don't be afraid to go lower, it is amazing how a model can make it back up the hill in the dead air.</blockquote>
<blockquote>Once you have the hang of the half circuit, move the top turn away from you (along the top of the hill) a bit more and try continuing on from the first half to the second half of the circuit. As the model passes through the boundary, correct the roll so that when you pull, the model heads back for the bottom turn point then pull. If you get the roll wrong, you will either hit the hill or end up too high for the bottom turn.</blockquote>
<p align="center"><a href="/articles/liftzone/2003/jan/ds/dscf0013.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/dscf0013_t.jpg" border="2"></a> <a href="/articles/liftzone/2003/jan/ds/dscf0014.jpg"><img src="http://static.rcgroups.com/articles/liftzone/2003/jan/ds/dscf0014_t.jpg" border="2"></a></p>
<blockquote>Once you have that working, then you should notice the model picking up speed. Try tightening the circuit and making it as horizontal as the conditions allow. If the circuit is more vertical, then you have to fight against gravity through the bottom turn. This means more drag and load on the airframe. </blockquote>
<blockquote>That's it for this month! If you have any questions, pop into the sailplanes section of the RC Groups forums where we have our own topic for DS. Next month I am going to show you that you don't need a massive razor back ridge to go DSing.</blockquote>