Descent: 10 feet (3 m)
Description:
This profile starts at Entrance Way (just above Kings Mountain)
and heads west. For the hill enthusiast, it
has a nice section of 18%. For the connoisseur, there are several
short climbs on the sideroads off Patrol Road. One in particular,
Patrol Court, starts with a left switchback that hits 23% on the
outside, and 28% on the inside.
Altimeter altitude
(Altitude linearly interpolated from altimeter
samples, and smoothed with a 0.04mi gaussian.)
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Each horizontal line is 100 feet. Each vertical
line is 0.2 miles. Gradiometer grade
(Grade linearly interpolated from gradiometer
samples, and smoothed with a 0.04mi gaussian.)
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Each horizontal line is 2% grade. Each vertical
line is 0.2 miles. Altimeter grade
(Grade linearly interpolated from altimeter
samples, and smoothed with a 0.20mi gaussian.)
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Each horizontal line is 2% grade. Each vertical
line is 0.2 miles. Comparison of grades
(Green grade is from the gradiometer, magenta grade
is from the altimeter, and white is where they
overlap.)
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Each horizontal line is 2% grade. Each vertical
line is 0.2 miles.
Overall (averaging my first 20 hills),
the gradiometer grade averages 0.63 (% grade)
higher than the altimeter grade, with a standard
deviation of 4.5 (% grade per road).
This error may be due to:
-
Uneven sampling -- I take more samples when the
hill gets steep.
-
Calibration error (of the gradiometer or
altimeter).
In the end, though, I think that each individual
sample is accurate to within about 2% for that
instantaneous segment of road. My results may
not always agree with my altimeter, but they are
generally repeatable within 1%. I think that
I just need to take more samples to generate
more accurate graphs.
Raw Data:
Dist Grade Alti. Location
---- ----- ------ --------
0.00 -6% 570 Entrance Way
0.03 7% 560 635
0.08 10% 590 entering left turn
0.14 11% 620 660
0.17 11% 640 Patrol Court
0.22 6% 650
0.26 13% 670
0.28 15% 690
0.32 16% 720
0.35 8% 740 steep section looms ahead
0.37 18% 750 725
0.39 18% 770
0.44 17% 810 780
0.47 16% 840
0.52 5% 860 Roan Pl.
0.60 8% 880 850
0.65 10% 900
0.70 0% 920
0.73 0% 920 dead end
Back to
Lucas's
cycling gradiometer page.