George MacArthur 3 Kari Court Lindsay Ontario Canada K9V 6B7 705-878-9878 geomac@cogeco.ca www.georgemacarthur.com March 15 2013
Kay Brackins AHS International 217 North Washington Street Alexandria VA 22314
Dear Ms. Brackins: I will be entering the Sikorsky Prize competition sometime in the near future. In the meantime, I have discovered two contradictions in the Sikorsky Prize rules. They are as follows: 4.4.1 The flight requirements shall consist of hovering for one minute while maintaining flight within a 10-meter square. During this time, the lowest part of the machine shall exceed momentarily 3 meters above the ground. Consider the following scenario: On the same day, two teams competing for the Sikorsky Prize center their machines in the square, climb over 3 meters in altitude, and stay airborne for more than 60 seconds. At the 60 second mark, team A has drifted 5.1 meters from the start point orthogonally with respect to the square, and team B has drifted 7 meters diagonally. The attempt of team A will be nullified for drifting outside the square and team B will win the prize, even though team B exercised much less flight control by drifting 37% farther than team A, and team B will have won by virtue of the chance of drifting in an advantageous direction. The square boundary criterion is in fact variable, and whether a given flight is deemed prize winning may depend upon the direction of drift. There are four regions within the square where a machine can drift as much as 7.071 meters and still win the prize, and these regions are located on the diagonal lines, while there are four regions that a machine can drift no more than 5 meters to win, and these regions are located on the orthogonal lines. Please see diagram. The solution is to change the rule to instead specify a circle 10 meters in diameter, thus eliminating the varying boundary and the element of chance.