I computed this efficiency for my 2008 Science Olympiad Wright Stuff plane. This plane, when flown at Kibbie in 2008 with April 2006 Tan SS rubber, wound to 0.89 oz-in, had:
total weight = 9g
rubber weight = 1.9g (2g with rubber o-rings)
wing area = 54.25 si
stab area = 20.93 si
time = 7.27 minutes
The "Kang Efficiency" works out to be 11.91. I assume all the other planes used Tan II rubber.
Oh, I did try this plane, ballasted to the 2015 SO rules to 10g total weight with the the same motor weight of 1.9g using 3-02 rubber (at .85 oz-in), at LH this past labor day. The plane flew 7:03 (7.05 minutes). With the better rubber, the "Kang Efficiency" was 13.53. BTW, the same plane at Kibbie lastyear had an KE of 12.04 using the same April 2006 Tan SS rubber so the numbers are consistent.
I doubt my poor old SO plane is as efficient, especially with it's plastic Ikara prop, as the true duration planes listed in Kang's chart. I think that the KE is more a measure, as Kang alluded too in his original post, of how much energy of the total available is used in the flight rather than a measure of the efficiency of the plane.
LeoP
Received on Fri Feb 19 2016 - 21:13:16 CET
This archive was generated by Yannick on Sat Dec 14 2019 - 19:13:48 CET