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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