Finessometer

A "finessometer" is a geometric device to measure angles with respect to the horizontal. It can be from utility to measure the inclination of the mountain or of our trajectory being foreseen of flight.
Years ago, when the paragliders were not very performing (3 or 4 points of finesse = glide ratio), had to be taken very into account in which finesse had our landing field.
Nowadays, with 8 points or month of glide ratio we have it better, but to know in which finesse had our usual field is continues being an interesting datum. With this device this finesse can be measured. In spite of their rudimentary look and "low-tech", if constructs well, has more precision of what one can think... And it is not a device to use in flight..., only from the point of takeoff or of landing.

Principle of functioning of the finessometer

Instructions:

1) The finessòmetre was formed by two bars AB and CD, joined to an articulation at point C, that him the point half of AB. The bar AB is the double of long that the CD.
2) Him suspends the device from point D, so that bar DC comes off vertical for the action of the gravity.
3) The bar AB is orientated according to the trajectory or inclination which it is wanted to measure.
4) It is a matter of measuring the distance "of" among the points To and D, since this separates it is related with the angle "alpha" that it forms the bar with the horizontal as month is deduced from the indicated geometric formulation down.
5) To facilitate the conversion the table corresponding to a finessometer with L=10 cm has been prepared here:

Table to convert the moderate distance "d" among A and D (in cm), with values of angle with respect to the horizontal (degres) or values of fineness "f": (application in a finessometer of side L=10 cm).

 Finessòmetre (AB=20 cm CD=10 cm) L= 10 cm distància “d” angle finesa “f” (cm) (graus deg) 0,00 90,00 0,00 1,00 84,27 0,10 2,00 78,52 0,20 3,00 72,75 0,31 4,00 66,93 0,43 5,00 61,04 0,55 6,00 55,08 0,70 7,00 49,03 0,87 8,00 42,84 1,08 9,00 36,51 1,35 10,00 30,00 1,73 10,10 29,34 1,78 10,20 28,67 1,83 10,30 28,01 1,88 10,40 27,34 1,93 10,50 26,66 1,99 10,60 25,99 2,05 10,70 25,31 2,11 10,80 24,63 2,18 10,90 23,95 2,25 11,00 23,27 2,33 11,10 22,58 2,40 11,20 21,89 2,49 11,30 21,20 2,58 11,40 20,50 2,67 11,50 19,80 2,78 11,60 19,10 2,89 11,70 18,39 3,01 11,80 17,69 3,14 11,90 16,97 3,28 12,00 16,26 3,43 12,10 15,54 3,60 12,20 14,82 3,78 12,30 14,10 3,98 12,40 13,37 4,21 12,50 12,64 4,46 12,60 11,90 4,75 12,70 11,16 5,07 12,80 10,42 5,44 12,90 9,67 5,87 13,00 8,92 6,37 13,10 8,16 6,97 13,20 7,40 7,70 13,30 6,64 8,60 13,40 5,87 9,73 13,50 5,09 11,22 13,60 4,31 13,26 13,70 3,53 16,22 13,80 2,74 20,90 13,90 1,95 29,44 14,00 1,15 49,99

6) Note: geometric principle of the finessometer:

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