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<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="0" CELLSPACING="2" WIDTH="99" BORDERCOLORLIGHT="#808080" BORDERCOLORDARK="#FFFFFF" FRAME="BOX" RULES="ALL" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=CENTER HEIGHT= 20 WIDTH="95"><div> <B> </B><FONT SIZE="2" COLOR="#FFFFFF" FACE="Arial" ><A HREF="index.htm" TARGET="_top" TITLE="Home Page"><U><B>Home</B></U></A></FONT></div> </tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 20 WIDTH="95"><div> <B> </B><FONT SIZE="2" COLOR="#FFFFFF" FACE="Arial" ><A HREF="id2.htm" TARGET="_top" TITLE="Archive"><U><B>Archive</B></U></A></FONT></div> </tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 20 WIDTH="95"><div> <B> </B><FONT SIZE="2" COLOR="#FFFFFF" FACE="Arial" ><A HREF="id5.htm" TARGET="_top" TITLE="Contact"><U><B>Contact</B></U></A></FONT></div> </tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 20 ><NOBR><div> <B> </B><FONT SIZE="2" COLOR="#FFFFFF" FACE="Arial" ><A HREF="id6.htm" TARGET="_top" TITLE="Downloads"><U><B>Downloads</B></U></A></FONT></div> </NOBR></tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 20 WIDTH="95"><div> <B> </B><FONT SIZE="2" COLOR="#FFFFFF" FACE="Arial" ><A HREF="id7.htm" TARGET="_top" TITLE="Events"><U><B>Events</B></U></A></FONT></div> </tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 20 WIDTH="95"><div> <B> </B><FONT SIZE="2" COLOR="#FFFFFF" FACE="Arial" ><A HREF="id8.htm" TARGET="_top" TITLE="For Sale"><U><B>For Sale</B></U></A></FONT></div> </tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 20 WIDTH="95"><div> <B> </B><FONT SIZE="2" COLOR="#FFFFFF" FACE="Arial" ><A HREF="id9.htm" TARGET="_top" TITLE="Galleries"><U><B>Galleries</B></U></A></FONT></div> </tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 20 WIDTH="95"><div> <B> </B><FONT SIZE="2" COLOR="#FFFFFF" FACE="Arial" ><A HREF="id14.htm" TARGET="_top" TITLE="Games"><U><B>Games</B></U></A></FONT></div> </tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 20 WIDTH="95"><div> <B> </B><FONT SIZE="2" COLOR="#FFFFFF" FACE="Arial" ><A HREF="id15.htm" TARGET="_top" TITLE="Links"><U><B>Links</B></U></A></FONT></div> </tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 20 WIDTH="95"><div> <B> </B><FONT SIZE="2" COLOR="#FFFFFF" FACE="Arial" ><B>Magazine</B></FONT></div> </tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 20 ><NOBR><div> <B> </B><FONT SIZE="2" COLOR="#FFFFFF" FACE="Arial" ><A HREF="id17.htm" TARGET="_top" TITLE="Newsletter"><U><B>Newsletter</B></U></A></FONT></div> </NOBR></tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 20 ><NOBR><div> <B> </B><FONT SIZE="2" COLOR="#FFFFFF" FACE="Arial" ><A HREF="id18.htm" TARGET="_top" TITLE="Reference"><U><B>Reference</B></U></A></FONT></div> </NOBR></tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 19 WIDTH="95"><div> <B> </B><A HREF="id88.htm" TARGET="_top" TITLE="Video"><U><B>Video</B></U></A></div> </tD> </tR> <tR> <tD VALIGN=CENTER HEIGHT= 20 WIDTH="95"><div> <B> </B><FONT SIZE="2" COLOR="#FFFFFF" FACE="Arial" ><A HREF="id19.htm" TARGET="_top" TITLE="Weather"><U><B>Weather</B></U></A></FONT></div> </tD> </tR> </TABLE></B></div> <bR> <bR> </td> <td valign="top" colspan=2 height=100 BGCOLOR="#FFFFFF" TEXT="#080000" bgproperties="fixed" background="00f00640egerdp.jpg"> <bR> <bR> <bR> <div> <I><B>Magazine    </B></I></div> <div> <B> </B></div> </td> </tr><tr> <td valign="top" height=380 colspan=2 BGCOLOR="#FFFFFF" TEXT="#080000"> <div>  <STYLE>  </STYLE>  </div> <div> <TABLE BORDER="0" CELLPADDING="10" CELLSPACING="1" WIDTH="602" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=TOP HEIGHT= 1621 WIDTH="580"><div> <I><B>Virtually Free Aircraft!</B></I></div> <bR> <div> <IMG SRC="4b038d50.jpg" border=0 width="312" height="213" ALIGN="LEFT" HSPACE="10" VSPACE="0">While going over the fleet in preparation for the new season I discovered that the fibreglass fuselage of my Little Toot biplane was crazed nearly everywhere and had several severe fractures developing in high stress areas. As those of you who have read the Toot articles will know, this bird is massively overweight anyway (like 35%!) and mostly because of the terrible chopped matt fibreglass fuselage. The thought of adding even more heavy resin to effect repairs didn't appeal, as the whole process would only begin again as soon as I flew her. </div> <bR> <div> <IMG SRC="4af39b80.jpg" border=0 width="313" height="184" ALIGN="RIGHT" HSPACE="10" VSPACE="0">So, what to do? I could sell her, I thought, but it's not really fair to pass on something you know will be falling to bits after a few flights, is it? So I decided to scrap her. At about this time I had occasion to empty out the loft, and it's lucky I did because, while temporarily storing old and broken models in the spare room, an unlikely pairing was formed. The Toot wings and the fuselage from an old own design .25 powered low wing 30's type monoplane fell together and gave me the spark of an idea.</div> <bR> <div> <IMG SRC="4b338ea0.jpg" border=0 width="312" height="234" ALIGN="LEFT" HSPACE="10" VSPACE="0">The monoplane was also overweight after a broken wing repair involving a 3/16 ply dihedral brace over a foot long and copious gobs of epoxy, so it too was effectively a scrapper. I weighed the fuselage and wings and made a few estimates for engine and gear etc and came up with an all up weight of 7.5 to 8 lbs, giving a wing loading of 16 to 17 ozs sq ft. Nice! It should be a fine flyer, and looking at it sitting on the bottom wing and with the top wing balancing on an old fuel tank, it looked really nice, real 1930's. Also having a major influence to meld these two airframes was the realisation that I had two old four stroke engines sitting idle, one a .65 and the other a .91 ASP, both of which have identical crankcases allowing either engine to fit the same <IMG SRC="4b536ea0.jpg" border=0 width="310" height="234" ALIGN="RIGHT" HSPACE="10" VSPACE="12">mount, which could be useful. It's an unlikely pairing isn't it? The wings from a 23cc (1.40) powered aircraft and yet only a 4cc (.25) engine in the monoplane! In fact, the monoplane had a humble O.S. 26 four stroke before the wing repair made it too heavy! Well, I was quite excited about the whole thing now and couldn't wait to get on with it.</div> <bR> <div> So, once decided the first thing to do was hack out the tailplane and cabane from the Toot fuselage - not as easy as it may sound without destroying the parts I was trying to salvage! Damn fibreglass, I itched for days after that! The removal of the tail group from the monoplane was, by comparison, a piece of cake.</div> <bR> <div> <IMG SRC="4b638ea0.jpg" border=0 width="312" height="234" ALIGN="LEFT" HSPACE="10" VSPACE="12">The next task was to set the wing and tail incidence. The tail is set to 0 degrees parallel with the fuselage datum, so I needed ½ to 1 degree of positive incidence on the main wings. The wing seat for the lower wing had to be modified in any event because of the differing airfoil shapes. The monoplane had a NACA 2415 section and the Toot a NACA 2412. Both, conveniently, have a 10.25 inch chord. The bottom wing needed a little local reinforcement for the addition af a leading edge mounting dowel and once this was done I was able to drill the wing to line up with the original wing bolts mounts. A bit of shimming of the wing seat was required to achieve the correct incidence. </div> <bR> <div> Now I had something to measure from I could fit the cabane for the top wing. Ply patches were fitted inside the fuselage for the cabane to bolt to. The front cabane was drilled and positioned, then the rear <IMG SRC="4b738ea0.jpg" border=0 width="312" height="234" ALIGN="RIGHT" HSPACE="10" VSPACE="12">was drilled. One hole each side was slotted so the whole cabane could be tilted to adjust the wing incidence. This is about as far as I've got at the moment. The tail off the Toot is too heavy, so I'll make a new one - no problem, as it's only balsa sheet.</div> <bR> <div> I can't foresee any problems ahead, and judging by the numbers it should be a sweet flying aircraft. The best bit though is the utilisation of two otherwise scrap airframes! Why not have a look in your own loft, garage, shed or whatever, and see if you have a free new aircraft waiting in the wings! Part 2 coming soon! <I>G:-)</I></div> <bR> <div> <I>FF-19-01-07</I></div> </tD> </tR> </TABLE></div> <div> <IMG SRC="4bdc20f0.gif" border=0 width="450" height="271" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <div> <TABLE BORDER="0" CELLPADDING="10" CELLSPACING="1" WIDTH="602" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=TOP HEIGHT= 2789 WIDTH="580"><div> <I><B>Hanger 9 27% Extra 260</B></I></div> <bR> <div> <IMG SRC="4613abf0.jpg" border=0 width="314" height="191" ALIGN="LEFT" HSPACE="10" VSPACE="0">The Hanger 9 Extra 260 is a nice IMAC/3D aeroplane at a good price. I bought mine because I had a Moki 1.80 doing nothing and some reports I'd read claimed the Extra could weigh as little as 12 lbs ready to go, which meant the 1.8 would be powerful enough for 3D work. Mine has come out at 13 lbs despite a couple of weight saving mod's, but I should add there's a 3600 mah sub C NiMH powering the radio in there to help achieve the correct (in my case, most rearward) C.G.</div> <bR> <div> <IMG SRC="46239eb0.jpg" border=0 width="313" height="235" ALIGN="RIGHT" HSPACE="10" VSPACE="0">As it turns out this gives me a nice option should I discover I need more power in that I can fit the more powerful Moki 2.10, with no modification whatever, and which weighs another 4 odd ounces, which I can trade off against a smaller, lighter battery for no increase in overall weight. This is good because often fitting a bigger engine causes an unacceptable increase in weight, which could compromise 3D ability. </div> <div> The kit comes well packaged and everything was present and in good condition - no damage. The hardware is of good quality and up to the job.</div> <bR> <div> <IMG SRC="46339eb0.jpg" border=0 width="313" height="235" ALIGN="LEFT" HSPACE="10" VSPACE="0">Good quality ball links and Robart type hinges are supplied for the control surfaces, a carbon undercarriage, nice quality fibreglass cowl and spats, anodised wing and tail tubes, fuel tank, alloy engine mounts, wheels and a nice canopy. All in all a good package especially considering the price.</div> <bR> <div> There are many ways you can jump for model set-up. I opted for the light weight glow powered path, mainly, as I said, because I already had a Moki 1.80 doing nothing, but plenty of people are fitting 40 to 50cc petrol engines, but obviously the </div> <bR> <div> <IMG SRC="4653aec0.jpg" border=0 width="314" height="236" ALIGN="RIGHT" HSPACE="10" VSPACE="0">overall weight will escalate. 14 to 14.5 lbs should be possible with the likes of ZDZ40 to 50 or DA 50 engines. Once on this path, however, you have a lot of money floating around up there and users often opt for twin receivers and battery packs, often using Lipo's or Lion packs with regulators, and even opto isolators and so on. One British magazine's review model ended up at 17 lbs in this way, which I feel is way (weigh!?) too much for this size and area model, and while they may claim it performs beautifully anyone with an ounce of gumption would be very doubtful of this with wing loadings in the 35 ozs sq ft</div> <bR> <div> <IMG SRC="46839ea0.jpg" border=0 width="313" height="234" ALIGN="LEFT" HSPACE="10" VSPACE="0">range. That kind of loading would more normally be seen on 33 - 40% models and is, in fact, a relatively light loading for models of that size.  Maybe, if your thing was IMAC  style flying you'd be happy, but, at that weight, 3D would be severely compromised. My 13 lbs example has a wing loading of 26.5 ozs sq ft, which is far more like it (in my opinion).</div> <bR> <div> Okay, so the set-up is this: Moki 1.80 with Bisson (BCM) Pitts style in cowl muffler and Cline pressure regulator, turning a 20x 6 Mejzlik carbon propeller. Futaba radio with a single high torque servo for each </div> <bR> <div> <IMG SRC="46a3a270.jpg" border=0 width="314" height="295" ALIGN="RIGHT" HSPACE="10" VSPACE="0">control surface. 9.5 Kg for ailerons and rudder and 8Kg for elevators with a 3001 on throttle. All servo's are supplied by heavy duty extensions and a heavy duty rx switch. </div> <bR> <div> After weighing the supplied engine mounts I decided to go my own way and use a homemade mount system I've used a few times with complete success. The supplied mounts weighed in at 6 ounces, my home made mount, including all nuts, bolts and washers, just 3 ounces. The backplate itself is 1/8” duralamin. The stand off bolts are 5mm with “T” nuts in the firewall. Another advantage of this system is that the motor is full adjustable for up/down/side thrust. The pix show the arrangement.</div> <bR> <div> <IMG SRC="46c39eb0.jpg" border=0 width="313" height="235" ALIGN="LEFT" HSPACE="10" VSPACE="0">I decided to use a Cline pressure regulator on the engine after years of battling the throttle when prop' hanging as the engine leans once the nose is pointing skyward.. I have high hopes for this, but, as with so many modelling “solutions”, it could all end in abject failure, we'll see! Its operation is as follows: Fuel is pressurised in the tank from the crankcase of the engine via a one way check valve. Tank pressure is from 2 to 12 lbs PSI. This forces fuel to the regulator, which is mounted very close to the carburettor inlet nipple. The carb “sucks” on the regulator diaphragm</div> <bR> <div> <IMG SRC="47039eb0.jpg" border=0 width="313" height="235" ALIGN="RIGHT" HSPACE="10" VSPACE="0">causing it to open the fuel valve in the regulator. It is a demand regulator, the more the carb “sucks” the more fuel the regulator passes. When the engine is stopped no fuel can pass. To sum up, it is a proportional fuel control system. (We hope!)</div> <bR> <div> In theory it shouldn't matter what attitude or “G” the model has put on it, everything should be fine. The engine should “see” no change in fuel head at all. (Oi! You at the back, stop laughing!) Some mod's have to be made to the fuel tank (see pic) to prevent the fuel lines blowing off.</div> <bR> <div> <IMG SRC="46e3aec0.jpg" border=0 width="314" height="236" ALIGN="LEFT" HSPACE="10" VSPACE="0">Everything went together well and no problems were encountered. Hanger 9 really does have its act together with these ARTF's. It really is just an assembly job that could be accomplished in a week of evenings.</div> <bR> <div> One modification I did make was to the air exit of the cowling. A few people have had cooling issues when using big glow engines and some have gone to petrol engines (which are usually fitted inverted with the cylinder hanging out in the breeze) to solve this. </div> <bR> <div> The exit area, as ever, should be about 3 to 1, i.e. 3 times the inlet area. This leaves a pretty big hole, which also slopes back to the firewall. Its effect is to leave a big chunk of flat firewall presented directly into the air stream. I felt this was probably deflecting air into the cowl area and preventing the smooth flow of air passing through from the inlet. So I decided to make an air deflector as per full size around the exit lip to solve the problem. It took a little work to get right - there are some weird angles in there - but eventually I got it fairly right. See pix.</div> <bR> <div> The only other modification I made was to cut out the plywood cockpit floor, which saved about 11/2 ounces. Weight was also saved by using an Irvine spinner. This type has a lightened alloy backplate and a plastic nose. This saved almost 4 ounces over the usual polished alloy spinner.</div> <bR> <div> Anyway, it's all ready to go and I may get out with it soon. It'll take some time to get the motor fully run in before I can give you an accurate flight report, the general <IMG SRC="46f39eb0.jpg" border=0 width="313" height="235" ALIGN="RIGHT" HSPACE="10" VSPACE="12">feeling is about five gallons (ringed piston running on a hard chromed liner), so don't expect it till next spring. <I>G:-)</I></div> <bR> <div> <I><B>Spec's:</B></I></div> <bR> <div> Span:  78.25 ins</div> <div> Length:  71.25 ins</div> <div> Wing Area:  1134 sq ins</div> <div> Weight: 12 to 15.5 lbs</div> <div> Engines:</div> <div> 2 stroke 1.20 - 2.10</div> <div> 4 stroke 1.50 - 2.20</div> <div> Gas 35 - 50cc </div> <bR> <div> <I>FF-5-10-06</I></div> </tD> </tR> </TABLE></div> <div> <IMG SRC="48271070.gif" border=0 width="369" height="263" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <div> <TABLE BORDER="0" CELLPADDING="10" CELLSPACING="1" WIDTH="602" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=TOP HEIGHT= 2153 WIDTH="580"><div> <I><B>Extreme Flight Yak 55 SP-e</B></I></div> <bR> <div> <IMG SRC="40a3ad90.jpg" border=0 width="314" height="217" ALIGN="LEFT" HSPACE="10" VSPACE="0">The Extreme Flight Yak 55 SP-e is a small profile electric 3D ARTF with beautiful interlocking construction. You can buy one yourself here:</div> <bR> <div> <A HREF="http://www.freestyle-rc.com/html/products.asp" TARGET="_blank" TITLE="http://www.freestyle-rc.com/html/product"><U>http://www.freestyle-rc.com</U></A><A HREF="http://www.freestyle-rc.com/html/products.asp" TARGET="_blank" TITLE="http://www.freestyle-rc.com/html/product"><U>/</U></A></div> <bR> <div> I chose it because I wanted a small but 3D capable introduction to electric flight. I had zilch knowledge of electric matters and so wanted a complete package with the motor and speed control already picked for me. I also wanted ARTF and 3D capability.</div> <bR> <div> <IMG SRC="40b3ae70.jpg" border=0 width="314" height="231" ALIGN="RIGHT" HSPACE="10" VSPACE="0">My initial search for such a model was notable for its total confusion! Which motor for which model? Which speed control for which motor and motor type? What type of batteries are best for which type of motor? And so on. None of this was helped by the totally meaningless, to the newcomer at least, identification numbering systems of motors etc. However, it soon became obvious, even to a newbie like me, that Lithium Polymer batteries were the way to go. I was initially put off by the high cost of chargers but soon realised that some of the cheap 12v types were perfectly adequate. I use a Robbe Power Peak Lipoly 300. </div> <bR> <div> <IMG SRC="40c3aec0.jpg" border=0 width="314" height="236" ALIGN="LEFT" HSPACE="10" VSPACE="0">The search continued fruitlessly and confusingly and I was on the verge of giving up the whole idea when my Holy Grail appeared in the shape of a promo' video from Extreme Flight. It showed the lovely little aeroplane you see here, and it met all my criteria; small, 3D capable, ARTF and best of all it could be bought for a very attractive price with a geared brushless motor and speed control, better yet the amazing antics of the model shown in the promo' video used exactly those parts too, so I knew it would perform! The only parts for me to supply were radio gear and Lipo' batteries. The promo' video `plane used Hitec HS55 servo's and Thunder Power 1350 3 cell 11.1 volt Lipo', so that's what I bought too.</div> <bR> <div> <IMG SRC="40d3a110.jpg" border=0 width="314" height="273" ALIGN="RIGHT" HSPACE="10" VSPACE="0">Building, if that's the word, the model is quick and easy, there really isn't much to do at all. Fitting the control horns, push rod guides, radio gear, motor and speed control is about all there is to it. I fitted the Lipo' on Velcro so that it would be easy to swap them over during a flying session, and this works well. I haven't lost a Lipo' yet! Servo's are conventionally mounted and I fitted the receiver inside the wing with its own hatch, which also mounts the receiver switch. The aerial trails down the fuselage and behind as usual. I set all control surfaces for as much throw as I could get. The Hitec HS55 servo's are fast and accurate, unlike some of their bigger brethren. I also fitted an audible low voltage warning alarm which cost £12. This protects your Lipo's from low voltage damage.</div> <bR> <div> <IMG SRC="40e3ade0.jpg" border=0 width="314" height="222" ALIGN="LEFT" HSPACE="10" VSPACE="0">Flying the thing is fun, fun, fun! It's capable of just about anything and then some. I needed a little mixing for knife edge flight - about 6% up elevator correction for full rudder, mind you, I have a lot of travel on the rudder and to be honest, that amount isn't needed. I've managed to crash it quite badly on three occasions, once when trying to catch it from a hover, I caught the rudder with my hand as I made a grab for it and flipped it straight into the ground! The second time was due to losing synchronisation during low harrier rolls, and lastly, I flew it into my lower leg at high speed. Those of you who have flown this type of model will nod sagely and smile, while those who have not will think I'm an idiot… The damage in each case was to the nose only and was readily repaired.</div> <bR> <div> <IMG SRC="4113aec0.jpg" border=0 width="314" height="236" ALIGN="RIGHT" HSPACE="10" VSPACE="0">The model draws you into doing things you wouldn't ordinarily attempt, and therein lies its strength, because in attempting this stuff you're learning all the while. High alpha knife flight is one of its specialities and all the usual 3D moves are easily accomplished. Use plenty of expo' if you have extreme throws otherwise normal flight is pretty twitchy. On reduced throws it's a nice and safe model to fly and could be handled by anyone who's through the basic trainer stage. It can handle a good breeze and in fact can be a lot of fun when the wind is up. All in all a good and useful introduction to electric flight for the more advanced modeller looking for a first electric or someone on the early learning curve wanting to get into 3D flying.</div> <bR> <div> <IMG SRC="4183ad90.jpg" border=0 width="314" height="217" ALIGN="LEFT" HSPACE="10" VSPACE="0">Yes, all the stories are true - what a delight it is to go flying without all the usual stuff you have to cart around. Also you can fly virtually anywhwere. There's very little noise and somehow, because of this, there seems to be less general stress. Electric is ideal for 3D flying as you're not having to fight the engine the whole time as it leans or stumbles depending on which way the nose is pointing and, of course, you don't have to worry about it suddenly going quiet! Throttle response compared to a glow motor is simply amazing. And when the day is done everything is clean and oil free too.<I> G:-)</I></div> <bR> <div> <I><B><IMG SRC="4103ae90.jpg" border=0 width="314" height="233" ALIGN="RIGHT" HSPACE="10" VSPACE="0">Spec's:</B></I></div> <bR> <div> Span:  30.5 inches</div> <div> Length:  31.5 inches</div> <div> Wing Area:  320 sq ins</div> <div> AUW:  14 - 16 ounces</div> <div> Extreme Flight BL-20 brushless geared motor</div> <div> 15 Amp ESC</div> <div> 10x4.7 prop'</div> <div> HS-55 servo's</div> <div> Webra RX</div> <bR> <div> <I>FF-20-6-06</I></div> </tD> </tR> </TABLE></div> <div> <IMG SRC="41b405f0.gif" border=0 width="320" height="351" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <div> <TABLE BORDER="0" CELLPADDING="10" CELLSPACING="1" WIDTH="602" BORDERCOLORLIGHT="#C0C0C0" BORDERCOLORDARK="#808080" FRAME="BOX" RULES="ALL" HSPACE="0" VSPACE="0" > <tR> <tD VALIGN=TOP HEIGHT= 2647 WIDTH="580"><div> <I><B> <A NAME="cap_21_part_4___3d_conversion"><IMG BORDER="0" SRC="1x1.gif" HEIGHT="1" ALIGN="bottom" WIDTH="1" HSPACE="0" VSPACE="0" ></A></B></I><I><B>CAP 21 Part 4 - 3D Conversion</B></I></div> <bR> <div> <IMG SRC="3ae3aed0.jpg" border=0 width="314" height="237" ALIGN="LEFT" HSPACE="5" VSPACE="5">I finished the last article on this `plane by saying, “… what more could one ask?”. Well, I'll tell you; 3D matey, that's what! </div> <div> (<FONT SIZE="2" COLOR="#0000CC" FACE="Arial" ><A HREF="id52.htm" TARGET="_top" TITLE="Archive/Old Mag/CAP 21 Part1"><U>Click Here for Parts 1, 2, & 3</U></A></FONT>) When the CAP was originally finished there wasn't much in the way of 3D flying at that time, and even though I was hovering all over the place with a Limbo Dancer, to the consternation of many of our more wimpy members, the thought of hovering and 3D'ing the CAP never entered my feeble mind. After all, we're talking about a 30 year old design here, not some modern smart arse new kid on the block 3D A.R.T.F. Pat French may have been a good designer, but he couldn't have foreseen the development of 3D way back then.</div> <bR> <div> <IMG SRC="3b33aec0.jpg" border=0 width="314" height="236" ALIGN="RIGHT" HSPACE="5" VSPACE="5">When flying the CAP I'd noticed that the verticals eventually ran out of steam. Sometimes I'd try to prop' hang, at great height you understand, and it'd slide back after a few seconds every time. Also, it had a few frightening traits, namely a huge pitch down on the application of rudder, due I think, to the wing/tail incidence problem I mentioned in the previous article. This made snap rolls interesting as an inverted flick would get you an extra 180 degrees of rotation for exactly the same stick input as an upright flick - not something you want when hot dogging on the deck! Even stall turns would require full up at the point of rotation to stop it tucking under.</div> <bR> <div> Long after I'd stopped flying it in favour of more modern 3D'able designs, i.e. Funtana, I was wondering what I could get for it on E-Bay when the thought, “Pity it won't 3D.” slipped through my mind. Even before the thought had evaporated I had the tape measure out and was comparing elevator and rudder volumes with Funtana, Edge, Extra etc. </div> <bR> <div> <IMG SRC="3b23aec0.jpg" border=0 width="314" height="236" ALIGN="LEFT" HSPACE="5" VSPACE="5">I had an idea I could bevel the tail and fin to get more elevator and rudder movement. I also figured I could do it without unhinging the control surfaces, and that's just what I did! I just cut the corner off with a Stanley knife, gave it a light sand and covered with a strip of matching film that slotted between the hinges. I got about 50 degrees each way for the rudder and elevators. The ailerons, although looking a little small for 3D, were nonetheless pretty big for a normal aerobatic model. Really I needed to cut into the wing and make new and bigger ailerons, but, as I'm a lazy S.O.B. I decided not to worry about it right now and just get everything else done first!</div> <bR> <div> <IMG SRC="3b53aec0.jpg" border=0 width="314" height="236" ALIGN="RIGHT" HSPACE="5" VSPACE="5">The separate elevators were originally driven by a pair of heavy duty snakes, but they wouldn't bend enough with the big arc described by the control surface horn at 40 degrees plus each way. It looked as though twin elevator servo's mounted in the rear fuselage was the only way to go. I wasn't keen on this as two servos and linkages in the tail would make it tail heavy. That'd mean lead in the nose and the weight increase wouldn't help 3D'ability at all. So what to do? In the end I joined the elevator halves with a 6 gauge piano wire joiner and drove them via a carbon push rod, with ball joints either end, from the single servo mounted under the wing seat in the fuselage. And it works brilliantly and saves the weight and cost of an extra servo! The rudder remains pull/pull cable driven.</div> <bR> <div> <IMG SRC="3b73aec0.jpg" border=0 width="314" height="236" ALIGN="LEFT" HSPACE="5" VSPACE="5">The next problem was - could it make enough thrust to hover? The model weighs 14.5 pounds and from everything I'd read on internet forums a 30cc (1.80) glow engine should have just enough. Obviously then - unless Super Tigre's were inferior to everything else - it should just be about the careful selection of the propeller. And at the 2004 Nat's I found just the thing in the shape of a brace of wooden 20 x 6 Smart propellers for a tenner - beat that! </div> <bR> <div> The next snag was the notorious Super Tigre rich midrange problem. A quick sortie on the internet to the Perry (carb' and pump) website revealed exactly the Perry carb' I needed for an unpumped installation (Part: 5001). I had to wait a couple of weeks for Just Engines to get one in stock, but it arrived exactly when they said it would. Hopefully, it would solve the problem.</div> <bR> <div> <IMG SRC="3b83aec0.jpg" border=0 width="314" height="236" ALIGN="RIGHT" HSPACE="5" VSPACE="5">The bigger propeller was now grazing the deck so a taller undercarriage was needed. Fortunately I had just the thing in the shape of a two piece ally job that had an extra couple of inches of lift and gave adequate clearance. Phew!</div> <bR> <div> So, back to the wing. I decided to bite the bullet and correct the wing incidence problem. The job wasn't as bad as I'd imagined it would be. I cut out toward the trailing edge of the wing seat and filed out the wing dowel mounting holes until I had 1 degree of positive incidence. After filling and sanding I found I now had 1.5 degrees! Ho hum! It still flies with down elevator but only a 10th of that used before. By the time I'd sorted the wing incidence problem I didn't have the enthusiasm left to hack out my wing for new and bigger ailerons. I decided to just double bevel them as per the tail surfaces and see how we went with that. 40 odd degrees each way was achieved and it certainly looked plenty enough! I also sealed the hinge lines with film on both ailerons and elevators.</div> <bR> <div> <IMG SRC="3b93aec0.jpg" border=0 width="314" height="236" ALIGN="LEFT" HSPACE="5" VSPACE="5">So, how's it fly? Well, still quirky but a lot of fun. Harrier rolls are difficult to maintain, probably because of those slow old Hitec jumbo servo's not keeping up, plus I'm no expert! It hovers and torque rolls okay, the 20 x 6 prop' developing loads of thrust compared to the original 18 x 8. I haven't done any low hovering yet because of issues with the Perry carb'. The Super Tigre 3000 runs and throttles nicely throughout the range on its Perry carb' but leans out a lot when the nose is vertical, even when it's stumbling rich in level flight. I should have bought the pumped version! Also the needle valve has a habit of unscrewing itself in flight. Its only restraint is the rubber sealing ring - maybe I got a slack one. Consequently, I daren't trust it in a low hover. I'm told the O.S. 7D carb' is the one to have, so may try this later. When everything is right, however, it runs beautifully!</div> <bR> <div> <IMG SRC="3b0e3350.jpg" border=0 width="227" height="309" ALIGN="RIGHT" HSPACE="5" VSPACE="5">The motor has now had a season running on fuel containing 9%castor, 9% synthetic and 5% nitro. Despite dire warnings from the importer there have been no adverse effects. The recommended 11% total oil content runs too hot for me, the engine not sounding or feeling happy. You tend to get picky about things like this when it's hanging on the prop' five feet off the deck!</div> <bR> <div> The ailerons turned out to be just effective enough when hovering unless a gust of wind pushes it round. Interestingly the last one third of aileron movement seems to have no noticeable effect, so the only way to get more aileron power would be broader chord ailerons. All in all I'm pretty happy with it, quirks and all. It does the most amazing waterfall, when I can nail it, rotating around the C.G. absolutely on the spot just like the full size. This is the only model I've ever had that would do this. Oddly, It'll only do it inverted; it won't even consider it upright! The relatively heavy wing also likes to carry on rotatating in flick manoeuvres, making low level larking about a bit dangerous. The upright to inverted flick difference is still there but not as extreme as it was.</div> <bR> <div> So overall it's a success. It gets me used to the look and feel of a largish model, has expanded its repertoire to include 3D manoeuvres, untidy but do-able nonetheless, and I'm looking forward to flying it again this season. I feel better servo's would make a big difference to it, but have you seen the price of 10kg digitals? Phew! <I>G:-)</I></div> <div> <I>FF-27-4-06</I></div> </tD> </tR> </TABLE></div> <div> <IMG SRC="3c3c27b0.gif" border=0 width="450" height="379" ALIGN="BOTTOM" HSPACE="0" VSPACE="0"></div> <bR> <bR> <bR> <div> <FONT SIZE="2" COLOR="#000000" FACE="Arial" >Articles from this page wind up in the</FONT> <A HREF="id2.htm" TARGET="_top" TITLE="Archive"><U>Archive</U></A> <FONT SIZE="2" COLOR="#000000" FACE="Arial" >page if it's just a general article, </FONT></div> <div> <FONT SIZE="2" COLOR="#000000" FACE="Arial" >or the </FONT><A HREF="id18.htm" TARGET="_top" TITLE="Reference"><U>Reference</U></A> <FONT SIZE="2" COLOR="#000000" FACE="Arial" >page if the article is of a more technical nature.</FONT></div> <bR> <bR> </td> </tr></table></body>