MADRES build review
Herewith my winter project, assembling a MADRES 2m for the forthcoming BARCS 2 week postal challenge instigated by Jon Whitmore and run by Tony Beckett.
The design of the MADRES is very much outside of my comfort zone with an AR of 16:1, an EDA of 8.6degs and a 4.5% root thickness, it promises a brisk straight line performance. Sink rate and roll/yaw coupling might be an issue but nothing ventured, nothing gained. The promise of a fully machined CNC balsa wing was too much to resist. Assembly was uneventful, Hyperflight had supplied a passable translation of the German and there were no major hiccups. I made a few changes which included:_
I finished the wing with 3 coats of B and Q exterior satin polyurethane rubbed down between coats. With little attempt at weight saving, the RTF weight came out at 360gms with no added nose weight.
AVIONICS:The RU/EL servos were cheap EMAX ES08 but I had to use a expensive spare X08 for the spoiler as the fuselage width is only a mere 22mm wide under the wing. This was a fiddly job using a 0.38mm piano wire push rod. The RX is an MPX RX5 M-link with an MPX altimeter driven by a 300mah 2s LiPo and a Zepsus magnetic switch with a 5v BEC regulator.