The design report

Wing planform design 3.1.5
The wing shape had to be a new idea. The group decided against a rectangular wing as it
would have made the iSpy look ordinary. A wing with curved edges was most suitable to
make the iSpy more visually pleasing. A high wing configuration was chosen due to ease
of fabrication. It was decided not to have sweep, dihedral or winglets due to the added
complexity with fabrication and also due to the fact that the additions to lift would be
negligible in low speed flight. According to the initial plan, the wing chord had to be as
small as possible. A wing loading of 7 kg/m 2 gave a chord length of 22cm. This was still
not very thin but the professor suggested that an aspect of over 10 would be too high.
The wing chord had to be increased to bring the aspect ratio close to the suggested
figure of 8-9. After a lot of calculations to meet the specified criteria, a chord length of
26cm was chosen.
c (variable) b (fixed) AR Area Weight (fixed) W/S
0.21 2.3 11.39909035 0.464072118 3.6 7.75741498
0.22 2.3 10.90212414 0.485226542 3.6 7.419214917
0.23 2.3 10.44845137 0.506295126 3.6 7.110477303
0.24 2.3 10.0326608 0.527277868 3.6 6.827519635
0.25 2.3 9.650206988 0.54817477 3.6 6.567248612
0.26 2.3 9.297243807 0.568985832 3.6 6.327046825
0.27 2.3 8.970494923 0.589711052 3.6 6.104684636
0.28 2.3 8.667152053 0.610350432 3.6 5.898250925
0.29 2.3 8.384794267 0.630903971 3.6 5.706098178
Span 2.3 m
Chord 0.26 m
Area 0.56 m 2
Wing loading 6.32 kg/m 2
Aspect ratio 9.29
The sizing chosen above met all criteria set by the project guidelines and suggestions by
the professor. This however, changed the look of the iSpy meaning that an exact replica
of the global flyer wouldn’t be possible.