Archive/Old Mag/Autogyro Wingless

<body topmargin=0 leftmargin=0 marginheight=0 marginwidth=0> <table cellpadding=0 cellspacing=0 border=0><tr> <td valign="top" rowspan="2" width=156 BGCOLOR="#FFFFFF" TEXT="#080000" bgproperties="fixed" background="00e9cc00egerdp.jpg"> <div> <B> <STYLE>  </STYLE>  </B></div> <bR> <bR> <bR> <bR> <bR> <div> <B> <TABLE BORDER="0" CELLPADDING="2" CELLSPACING="1" WIDTH="97" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=TOP HEIGHT= 313 ><NOBR><div> <A HREF="index.htm" TARGET="_top" TITLE="Home Page"><U><B>Home</B></U></A></div> <div> <A HREF="id2.htm" TARGET="_top" TITLE="Archive"><U><B>Archive</B></U></A></div> <div> <A HREF="id5.php" TARGET="_top" TITLE="Contact"><U><B>Contact</B></U></A></div> <div> <A HREF="id6.htm" TARGET="_top" TITLE="Downloads"><U><B>Downloads</B></U></A></div> <div> <A HREF="id7.htm" TARGET="_top" TITLE="Events"><U><B>Events</B></U></A></div> <div> <A HREF="id8.htm" TARGET="_top" TITLE="For Sale"><U><B>For Sale</B></U></A></div> <div> <A HREF="id9.htm" TARGET="_top" TITLE="Galleries"><U><B>Galleries</B></U></A></div> <div> <A HREF="id14.htm" TARGET="_top" TITLE="Games"><U><B>Games</B></U></A></div> <div> <A HREF="id15.htm" TARGET="_top" TITLE="Links"><U><B>Links</B></U></A></div> <div> <A HREF="id16.htm" TARGET="_top" TITLE="Magazine"><U><B>Magazine</B></U></A></div> <div> <A HREF="id17.htm" TARGET="_top" TITLE="Newsletter"><U><B>Newsletter</B></U></A></div> <div> <A HREF="id18.htm" TARGET="_top" TITLE="Reference"><U><B>Reference</B></U></A></div> <div> <A HREF="id88.htm" TARGET="_top" TITLE="Video"><U><B>Video</B></U></A></div> <div> <A HREF="id19.htm" TARGET="_top" TITLE="Weather"><U><B>Weather</B></U></A></div> </NOBR></tD> </tR> </TABLE></B></div> <bR> </td> <td valign="top" colspan=2 height=100 BGCOLOR="#FFFFFF" TEXT="#080000" bgproperties="fixed" background="00f00640egerdp.jpg"> <bR> <bR> <bR> <div> <I><B>Archive </B></I></div> <div> </div> </td> </tr><tr> <td valign="top" height=380 colspan=2 BGCOLOR="#FFFFFF" TEXT="#080000"> <div> <FONT SIZE="2" COLOR="#000000" FACE="Arial" > <STYLE>  </STYLE>  </FONT><B><<   </B><A HREF="id50.htm" TARGET="_top" TITLE="Archive/MS Flight SIM Add Ons"><U><B> >></B></U></A></div> <div> <TABLE BORDER="0" CELLPADDING="25" CELLSPACING="1" WIDTH="602" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=TOP HEIGHT= 1074 WIDTH="550"><div> <I><B>Wingless Twin Rotor Autogyro Project</B></I></div> <div> <IMG SRC="31933f10.jpg" border=0 width="307" height="241" ALIGN="LEFT" HSPACE="5" VSPACE="5">This was built because I'd had a few "discussions" about whether the stub wings of most twin rotor autogyro's actually contribute to lift and control. The answer after building this was that they most definitely do!</div> <div> I'd had a DB Autogyro years ago and watched the rotors slow and even stop in flight. You could get them to stop over the top of a loop but the model still completed the loop and developed enough lift to pull out even though the rotors had not yet caught up. </div> <div> The model featured working sprung oleo's and all moving tailplane. The rotors were double ballraced and were mounted on 4mm allen cap bolts bolted through the aluminium booms. Many different types of rotor were tested: 3,4 and 5 blade arrangements with various airfoils, aspect ratio's and blade pitch were tried. Those used in the final version were 3 blade with a slight taper in planform and using a slimmed (about 10% thick) Clark Y airfoil. </div> <div> <IMG SRC="31a45e10.jpg" border=0 width="325" height="225" ALIGN="RIGHT" HSPACE="5" VSPACE="5">It was very underpowered on an old Webra Glo-Star of 3.5cc (.20), which in the testing stages saved me from disaster many times! It flew very slowly and was probably the most boring thing I've ever flown once it was in it's final form. The landings, even in the lightest breeze, were in the order of a pace or two. It could be so slow that you could fly off a 4oz tank in two circuits of the field! I kid you not.</div> <div> Experimentation like this is about the most fun you can have in aeromodelling, although it's sometimes heartbreaking when you've got to build yet another set of blades or whatever. There were other blade configurations that I'd have liked to try but I was just sick of making blades! </div> <div> <IMG SRC="31b15ec0.jpg" border=0 width="277" height="236" ALIGN="LEFT" HSPACE="5" VSPACE="5">She hung on the ceiling for a few years until I decided to fly her again. This time though I had an OS .25 up front and I'd unknowingly connected the all-moving tailplane with about double the required movement! And so when I flew her again she survived about 20 seconds. A sad end to a long and enjoyable project. I could have repaired her, but really I'd had enough. I'd done what I set out to do but the flying was not interesting enough to bother with more.</div> <div> However, don't let that put you off. It's an amazingly satisfying thing to do. It gives real purpose to your flying instead of the usual flying in circles everytime you go out. But, if you're happy to keep on buying someone else's designs then thats fine, but for some real satisfaction design something yourself! It's nowhere near as hard as you think! </div> <div> I may start a single rotor project sometime. There have been exciting developments in this field of late and it's beginning to look as if most of the problems have been worked out. I'll do a bit more on this later. </div> <div> It's funny how the more complex model helicopter was perfected before the more simple single rotor autogyro, don't you think? <I>G :-)</I></div> <div> <I>FF 10.2.01.</I></div> </tD> </tR> </TABLE></div> <div> <B><<   </B><A HREF="id50.htm" TARGET="_top" TITLE="Archive/MS Flight SIM Add Ons"><U><B> >></B></U></A></div> <bR> </td> </tr></table></body>