The entire community runs off the knowledge of others, recommending things for each other, building things for each other, coding things for each other. As I am trying to get some code together for later release it came to me that the maths I'd been using to help an RC Groups thread would be spot on for us. I of course posted it but changing it regularly (thanks to new model planes being released) has meant the file has to be uploaded continually to the thread so here is its own blog post. I actually posted an older one on my first blog but as I've altered it somewhat.

The file is nothing special in itself it just collates information and shows the viability of an airframe mathematically (not physically). The maths evaluates the attributes of an airframe to a few existing experiences (the first 10) on how difficult they were to fly this gives values on the beginner safe planes (wing loading). Again advice dictated to motor recommendations, 90w/lb is a base touted value for flight, 100w/lb is claimed to be perfect for gentle flight maneuvers. Spare mass is the mass you can add without the airframe going over the specified beginner "safe" values. The Additions part is to calculate the size of motor once you start adding stuff thats why a battery is first :)


Its certainly not definitive and its certainly not a bible but it should help the first timers or modders looking for a new toy. Just because the maths comes out fine it doesn't mean the plane will. As we have seen some planes are good EasyStar clones with similar specs but space inside them is 40% less thanks to giant walls. Research is your friend I just hope this does a little research for you. Values for the additions are in row 3 so make it bigger and change them if you want (APM is just the basic APM setup - APM + oilpan + MTK).


Feel free to post specs for planes that you want or like.

Data required: Name, Wingspan, Wing Area, Flying Mass

Name: Northrup GlobalHawk

Wingspan: 66ft

Wing Area: 169sqft


RC Plane Data

Views: 737

3D Robotics
Comment by Chris Anderson on February 1, 2011 at 8:19am
Ritchie: a suggestion--add a screenshot excerpt of your spreadsheet to the top of this post, so people can see what you have in mind, Most people won't download and open the spreadsheet just to understand what's in it.
Comment by Kim Skatun on February 1, 2011 at 9:57am
What about making Imperial units in sheet 2? and SI units in sheet1. Just makes it a bit easier to read..  Don't understand why people still uses imperial though :)

3D Robotics
Comment by Chris Anderson on February 1, 2011 at 10:16am
Comment by Ritchie on February 1, 2011 at 10:44am

Imperial and metric on one sheet for conversion reasons.

No problems Chris as always valuable insight.

Comment by T.D. Gonzales on February 1, 2011 at 11:19am
what about using google documents? I know we use them a lot in my classes.
Comment by mahmood on February 1, 2011 at 12:14pm
this is awesome thanks for the share
Comment by Shaw Innes on February 2, 2011 at 4:44am
I was thinking of making a web based thing like this. Do you think it would be used by the masses to form a comprehensive database?
Comment by Ritchie on February 2, 2011 at 4:48am

@T.D. Gonzales

I suppose I could but this is just something I knocked up to help others its not officially supported or nowt. If I get more planes on board I could upgrade to it. I am also tempted to create a tiny program to do the maths to help out but I'm not sure that would help any more than the spreadsheet and plus others wouldn't get the benefit of the details


No problems

Comment by Ritchie on February 2, 2011 at 5:08am


Well I've been very OCD about the numbers and used several sites to get the information checked and the worry is "outsiders" will see it as a joke to play while the rest of the genuine folks will find it helpful. Its a stupid concern really but I can currently back up all the figures using several vendors which means users can have faith in the information.

Incidentally a calculator was on my site but having switched ISP the site has come down (free space :D). It wasn't a database thing just a cruncher ( driven). Might get that up again this month but given the highest hits were for my counterstrike stuff I'm not too worried.

Comment by Kevin Vertucio on February 2, 2011 at 8:18am

This is helpful. Thanks!


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