The issue is, the airSpeed measured at the windMeter is not the airSpeed if, for example, you placed the windmeter a few feet out in front. There is a correction that must be applied to the wind speed.
If there is 0 wind, and I put the meter 10feet out in front of me, and I go 36km/h I will probably see 36km/h. If I put the meter 1m in front of my torso, I will probably see 33km/h, however 36km/h is the number I want to be using in my calcs.
Windmeter calibration is not trivial. Very coarse calibration is easy, very precise calibration is not.
In my case, the windmeter is mounted on an extension stick. I’m not sure it’s completely in free air, but the windspeed there should be close to that of free air.
In the eco challenge machine, they mounted it even closer to the body. The book doesn’t mention a correction factor.
There is a low pressure “bubble” above a train. So, if high pressure means a lower reading and low pressure means a higher reading for the windmeter, it could be overestimating the “true” airspeed (green). I raised the windmeter up but maybe it’s better to raise it even higher.
Hi, Robert I am having some trouble with Golden Cheetah. Hoping you could help or point me in the right direction. I am using a Garmin Edge 130. I turn off the GPS on the unit, I am using a magnet speed sensor. I feel like my route is good no brakes consistent lines. I do not get any elevation data, am I using the wrong head unit? Should I leave GPS on?
Hi, Robert I am having some trouble with Golden Cheetah. Hoping you could help or point me in the right direction. I am using a Garmin Edge 130. I turn off the GPS on the unit, I am using a magnet speed sensor. I feel like my route is good no brakes consistent lines. I do not get any elevation data, am I using the wrong head unit? Should I leave GPS on?
A 130 should have a barometer for altitude. However, maybe it needs GPS to initialize, really not sure.
I would do this. Turn on GPS. Put a speed field on the display, lift the wheel and spin it. If speed registers you know speed is being picked up by the speed sensor and you should be good.
Also, verify there is no altitude in the “performance chart” not in the Aerolab chart
