<html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:m="http://schemas.microsoft.com/office/2004/12/omml" xmlns="http://www.w3.org/TR/REC-html40"><head><meta http-equiv=Content-Type content="text/html; charset=utf-8"><meta name=Generator content="Microsoft Word 15 (filtered medium)"><style><!--
/* Font Definitions */
@font-face
{font-family:"Cambria Math";
panose-1:2 4 5 3 5 4 6 3 2 4;}
@font-face
{font-family:Calibri;
panose-1:2 15 5 2 2 2 4 3 2 4;}
@font-face
{font-family:"Segoe UI Emoji";
panose-1:2 11 5 2 4 2 4 2 2 3;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
font-size:11.0pt;
font-family:"Calibri",sans-serif;
mso-ligatures:standardcontextual;}
a:link, span.MsoHyperlink
{mso-style-priority:99;
color:#0563C1;
text-decoration:underline;}
span.EmailStyle19
{mso-style-type:personal-reply;
font-family:"Calibri",sans-serif;
color:windowtext;}
.MsoChpDefault
{mso-style-type:export-only;
font-size:10.0pt;}
@page WordSection1
{size:8.5in 11.0in;
margin:1.0in 1.0in 1.0in 1.0in;}
div.WordSection1
{page:WordSection1;}
--></style><!--[if gte mso 9]><xml>
<o:shapedefaults v:ext="edit" spidmax="1026" />
</xml><![endif]--><!--[if gte mso 9]><xml>
<o:shapelayout v:ext="edit">
<o:idmap v:ext="edit" data="1" />
</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72" style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal>Could always go back to SPA style. One pass one maneuver if they want it to look geometrically correct. Good points Andrew.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='mso-ligatures:none'>From:</span></b><span style='mso-ligatures:none'> NSRCA-discussion <nsrca-discussion-bounces@lists.nsrca.org> <b>On Behalf Of </b>Andrew Palmer via NSRCA-discussion<br><b>Sent:</b> Friday, April 7, 2023 3:09 AM<br><b>To:</b> nsrca-discussion@lists.nsrca.org<br><b>Subject:</b> [NSRCA-discussion] New FAI rule changes<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span lang=EN-NZ>I think others are now seeing the difficulty and problems with some of the (now passed) rule changes for F3A.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-NZ><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-NZ>The weight limit increase:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-NZ>I think few people would argue that nitro and electric models are not currently evenly matched for power – in fact most would say the electrics have an advantage both for usable power and constant speed.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-NZ>The weight change increase will mean electrics will become proportionally bigger (more bulky) than the nitro models will be able to. Why? Because weighing the nitro models with fuel will mean they can only ‘grow’ by say 150g, whereas an electric model can ‘grow’ by the full 500g. Historically F3A model specification changes have only ever lead to cost increase and a decrease in participation. Unfortunately I don’t really see a hundred (or even ten) people with models just over 5kg that will suddenly come out and fly F3A. Most countries don’t weigh models anyway, except maybe at a National Championships. In a couple of years we will all be trying to make it under the 5.5kg mark – and so the cycle will repeat. And all our current models will be outdate and not worth much… everyone will be looking for the new 5.5kg model to be competitive. And of course our 10s setups will be a bit exposed by the added power required – so another cost round if we go 12s….<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-NZ><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-NZ>The geometry ‘clarification’:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-NZ>This was described as a ‘clarification’, as it was (is) assumed this is how we are all flying and judging anyway. Which clearly we are not! America (like New Zealand and many other countries) has a long history of flying true geometry from the point of view of the aircraft. We innately understand how a loop flown at the end of the box will look (just like looking at a round circle on te wall from an angle). We are taught what a ‘true’ 45 degree line looks like at the end of the box….<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-NZ><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-NZ>Do I think anything will change with this clarification? Not really…. I think ‘everyone’ flies true geometry from the point of view of the model… and that will continue. The judges wont change what they are looking for. All that will happen is the rule book makes even less sense…. If a loop at the end of the box needs to look round from the point of view of the judges (BTW, see my demo video here: <a href="https://youtu.be/TDM0p_sWEGs">https://youtu.be/TDM0p_sWEGs</a> - lets see you do that at ‘constant 3D velocity) then what about a rolling circle? Oh hang on, of course a rolling circle does not need to look round from the point of view of the judges – they understand it will look like an ellipse… (just like they understand the shape of a true geometrically correct loop at the end of the box!). Lets see anyone fly a ½ 8 sided loop at the end of the box that is ‘geometrically correct from the point of view of the judges’ – it is impossible…..<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-NZ><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-NZ>Some of you may be aware of our autonomous aerobatic project (some info here: <a href="https://discuss.ardupilot.org/t/ardupilot-autonomous-aerobatics-update/99051">https://discuss.ardupilot.org/t/ardupilot-autonomous-aerobatics-update/99051</a> ) - the idea is for pilot and judge training. These manoeuvres are flown geometrically correct – and the schedule looks ‘right’. Over the next while we will work on flying manoeuvres that fit with the “judging criteria” – which will be a great demonstration as to why the rule is not workable </span><span lang=EN-NZ style='font-family:"Segoe UI Emoji",sans-serif'>😊</span><span lang=EN-NZ> <o:p></o:p></span></p><p class=MsoNormal><span lang=EN-NZ><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-NZ>Unfortunately I don’t have any good video, but for those interested here is a scale schedule example (all autonomous except take off and landing) flown in a howling gale </span><span lang=EN-NZ style='font-family:"Segoe UI Emoji",sans-serif'>😊</span><span lang=EN-NZ> <a href="https://youtu.be/dD6QmfTw4gM">https://youtu.be/dD6QmfTw4gM</a><o:p></o:p></span></p><p class=MsoNormal><span lang=EN-NZ><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-NZ>Andrew<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-NZ><o:p> </o:p></span></p></div></body></html>