airborneholt
New Member
- Joined
- Feb 9, 2009
- Messages
- 8
Hello,
I am looking for some help. I am trying to create a spreadsheet to help calculate average wind direction and velocity for Military Freefall parachuting (jumping out of an airplane from a high altitude while carrying equipment and wearing an oxygen mask). These calculations are then put into a formula to give map coordinates to where we want the plane to fly so that we can jump out and land at the designated landing area.
The wind data is given to me in a word document or spreadsheet and has altitude, direction and velocity for every thousand feet in altitude up to 50000.
for example:
alt dir vel
1000 280 12
2000 270 14
3000 260 10
In order to do this accurately and to have a spreadsheet that will work, there are a couple of variables. The exit altitude (how high the plane will be flying when we get out) and the opening altitude (the designated altitude that we open our parachutes).
The exit altitude can be from 5000-35000 feet and the opening altitude can be from 4000-25000 feet.
The basic rules to determine what wind data I need to start with are:
If opening altitude is 6000 or less, then I need wind data every 1000 feet from the ground to opening altitude and then every two thousand feet (on even numbers) to exit altitude.
If opening altitude is above 6000, then I need wind data every thousand feet from the ground to 10000, and then every two thousand feet to exit altitude.
Now, there are rules for the averaging. They are incompatable winds, erronious winds and dog legs.
Incompatable winds: winds are given in degrees (based on a 360 degree compass), so there is a problem averaging the wind direction when you have winds out the northwest and the northeast. For example, if you have one wind reading at 350 degrees and a second wind reading at 10 degrees, the real average of those two is 360 or 0 degrees, but the mathematical average is 180.
Erronious winds: sometimes the wind data is not perfect (imagine a weatherman giving you incorrect data), so if you get a wind reading that is more than 90 degrees off in one layer, then we do not use it in the average.
For example:
<TABLE style="WIDTH: 174pt; BORDER-COLLAPSE: collapse" border=0 cellSpacing=0 cellPadding=0 width=232 x:str><COLGROUP><COL style="WIDTH: 78pt; mso-width-source: userset; mso-width-alt: 3803" width=104><COL style="WIDTH: 48pt" span=2 width=64><TBODY><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: transparent; WIDTH: 78pt; HEIGHT: 12.75pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" height=17 width=104>Winds</TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: transparent; WIDTH: 48pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" width=64></TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: transparent; WIDTH: 48pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" width=64></TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17>Altitude</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24>Direction</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24>Velocity</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>24</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>280</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>25</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>22</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>285</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>22</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>20</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>260</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>22</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>18</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>105</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>20</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>16</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>265</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>22</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>14</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>270</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>18</TD></TR></TBODY></TABLE>
The wnds at altitude 18 are most likely an error, so we do not use this altitude in the calculation.
The proper way to determine this is to start at exit altitude working down in altitude and compare the wind direction to the one below it. If the wind direction is within 90 degrees (plus or minus) of the next reading, then it is acceptable and will be used in the average. If it is not within 90 degrees, then you need to look at the wind direction at the next lower altitude. If the wind direction at the next lower altitude is within 90 degrees of the original direction, then you eliminate the erronious wind data from the average and continue on.
In this example, you would take the top altitude and compare it to the one below it- 280 compared to 285. These are within 90 degrees of each other, so we go on to the next and compare 285 to 260. These are within 90 degrees of each other so we go on and compare 260 to 105. Since these are more than 90 degrees apart, we compare 260 to 265. These are within 90 degrees, so we consider the reading of 105 to be erronious and neither the wind drection or velocity at this altitude will be used for the average.
However, the next possibility is a dog leg. This is when the wind direction shifts over 90 degrees for two or more consecutive layers.
For example:
<TABLE style="WIDTH: 174pt; BORDER-COLLAPSE: collapse" border=0 cellSpacing=0 cellPadding=0 width=232 x:str><COLGROUP><COL style="WIDTH: 78pt; mso-width-source: userset; mso-width-alt: 3803" width=104><COL style="WIDTH: 48pt" span=2 width=64><TBODY><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: transparent; WIDTH: 78pt; HEIGHT: 12.75pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" height=17 width=104>Winds</TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: transparent; WIDTH: 48pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" width=64></TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: transparent; WIDTH: 48pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" width=64></TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17>Altitude</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24>Direction</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24>Velocity</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>24</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>280</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>25</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>22</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>285</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>22</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>20</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>260</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>22</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>18</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>105</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>20</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>16</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>100</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>22</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>14</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>105</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>18</TD></TR></TBODY></TABLE>
In this case, the winds clearly shifted direction between altitudes 20 and 18. In this example, we do the same thing: you would take the top altitude and compare it to the one below it- 280 compared to 285. These are within 90 degrees of each other, so we go on to the next and compare 285 to 260. These are within 90 degrees of each other so we go on and compare 260 to 105. Since these are more than 90 degrees apart, we compare 260 to 100. These are also more than 90 degrees apart, so we have a dog leg. In this case, we will do two separate averages.
I know that this is long and complicated, and I would appreciate any help.
To sum up, what I hope to accomplish with this is to create a spreadsheet that I can type in the exit altitude and opening altitude, and then run a script which will give me a table to enter my wind data into. Once I have typed the wind data in, I will run another script that will give me the average direction and average velocity from exit altitude to opening altitude and the average direction and average velocity from opening altitude the ground (or give me multiple averages if there are dog legs).
Then I will run those numbers into a formula that determines where I want the plane to fly so that I can jump out and land at the right spot.
Thank you,
Jeff
I am looking for some help. I am trying to create a spreadsheet to help calculate average wind direction and velocity for Military Freefall parachuting (jumping out of an airplane from a high altitude while carrying equipment and wearing an oxygen mask). These calculations are then put into a formula to give map coordinates to where we want the plane to fly so that we can jump out and land at the designated landing area.
The wind data is given to me in a word document or spreadsheet and has altitude, direction and velocity for every thousand feet in altitude up to 50000.
for example:
alt dir vel
1000 280 12
2000 270 14
3000 260 10
In order to do this accurately and to have a spreadsheet that will work, there are a couple of variables. The exit altitude (how high the plane will be flying when we get out) and the opening altitude (the designated altitude that we open our parachutes).
The exit altitude can be from 5000-35000 feet and the opening altitude can be from 4000-25000 feet.
The basic rules to determine what wind data I need to start with are:
If opening altitude is 6000 or less, then I need wind data every 1000 feet from the ground to opening altitude and then every two thousand feet (on even numbers) to exit altitude.
If opening altitude is above 6000, then I need wind data every thousand feet from the ground to 10000, and then every two thousand feet to exit altitude.
Now, there are rules for the averaging. They are incompatable winds, erronious winds and dog legs.
Incompatable winds: winds are given in degrees (based on a 360 degree compass), so there is a problem averaging the wind direction when you have winds out the northwest and the northeast. For example, if you have one wind reading at 350 degrees and a second wind reading at 10 degrees, the real average of those two is 360 or 0 degrees, but the mathematical average is 180.
Erronious winds: sometimes the wind data is not perfect (imagine a weatherman giving you incorrect data), so if you get a wind reading that is more than 90 degrees off in one layer, then we do not use it in the average.
For example:
<TABLE style="WIDTH: 174pt; BORDER-COLLAPSE: collapse" border=0 cellSpacing=0 cellPadding=0 width=232 x:str><COLGROUP><COL style="WIDTH: 78pt; mso-width-source: userset; mso-width-alt: 3803" width=104><COL style="WIDTH: 48pt" span=2 width=64><TBODY><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: transparent; WIDTH: 78pt; HEIGHT: 12.75pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" height=17 width=104>Winds</TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: transparent; WIDTH: 48pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" width=64></TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: transparent; WIDTH: 48pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" width=64></TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17>Altitude</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24>Direction</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24>Velocity</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>24</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>280</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>25</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>22</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>285</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>22</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>20</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>260</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>22</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>18</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>105</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>20</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>16</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>265</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>22</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>14</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>270</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>18</TD></TR></TBODY></TABLE>
The wnds at altitude 18 are most likely an error, so we do not use this altitude in the calculation.
The proper way to determine this is to start at exit altitude working down in altitude and compare the wind direction to the one below it. If the wind direction is within 90 degrees (plus or minus) of the next reading, then it is acceptable and will be used in the average. If it is not within 90 degrees, then you need to look at the wind direction at the next lower altitude. If the wind direction at the next lower altitude is within 90 degrees of the original direction, then you eliminate the erronious wind data from the average and continue on.
In this example, you would take the top altitude and compare it to the one below it- 280 compared to 285. These are within 90 degrees of each other, so we go on to the next and compare 285 to 260. These are within 90 degrees of each other so we go on and compare 260 to 105. Since these are more than 90 degrees apart, we compare 260 to 265. These are within 90 degrees, so we consider the reading of 105 to be erronious and neither the wind drection or velocity at this altitude will be used for the average.
However, the next possibility is a dog leg. This is when the wind direction shifts over 90 degrees for two or more consecutive layers.
For example:
<TABLE style="WIDTH: 174pt; BORDER-COLLAPSE: collapse" border=0 cellSpacing=0 cellPadding=0 width=232 x:str><COLGROUP><COL style="WIDTH: 78pt; mso-width-source: userset; mso-width-alt: 3803" width=104><COL style="WIDTH: 48pt" span=2 width=64><TBODY><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: transparent; WIDTH: 78pt; HEIGHT: 12.75pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" height=17 width=104>Winds</TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: transparent; WIDTH: 48pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" width=64></TD><TD style="BORDER-BOTTOM: #ece9d8; BORDER-LEFT: #ece9d8; BACKGROUND-COLOR: transparent; WIDTH: 48pt; BORDER-TOP: #ece9d8; BORDER-RIGHT: #ece9d8" width=64></TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17>Altitude</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24>Direction</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext 0.5pt solid; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24>Velocity</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>24</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>280</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>25</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>22</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>285</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>22</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>20</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>260</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>22</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>18</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>105</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>20</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>16</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>100</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>22</TD></TR><TR style="HEIGHT: 12.75pt" height=17><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext 0.5pt solid; BACKGROUND-COLOR: transparent; HEIGHT: 12.75pt; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 height=17 align=right x:num>14</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>105</TD><TD style="BORDER-BOTTOM: windowtext 0.5pt solid; BORDER-LEFT: windowtext; BACKGROUND-COLOR: transparent; BORDER-TOP: windowtext; BORDER-RIGHT: windowtext 0.5pt solid" class=xl24 align=right x:num>18</TD></TR></TBODY></TABLE>
In this case, the winds clearly shifted direction between altitudes 20 and 18. In this example, we do the same thing: you would take the top altitude and compare it to the one below it- 280 compared to 285. These are within 90 degrees of each other, so we go on to the next and compare 285 to 260. These are within 90 degrees of each other so we go on and compare 260 to 105. Since these are more than 90 degrees apart, we compare 260 to 100. These are also more than 90 degrees apart, so we have a dog leg. In this case, we will do two separate averages.
I know that this is long and complicated, and I would appreciate any help.
To sum up, what I hope to accomplish with this is to create a spreadsheet that I can type in the exit altitude and opening altitude, and then run a script which will give me a table to enter my wind data into. Once I have typed the wind data in, I will run another script that will give me the average direction and average velocity from exit altitude to opening altitude and the average direction and average velocity from opening altitude the ground (or give me multiple averages if there are dog legs).
Then I will run those numbers into a formula that determines where I want the plane to fly so that I can jump out and land at the right spot.
Thank you,
Jeff
