Crosswind Jump Runs

Have you read the Spotting Basics? 

Sometimes a crosswind jump run is beneficial if the landing area is a long, narrow rectangle and one side has a real “no-no” of a hazard. This would be a crosswind jump run with an “offset.” Say your landing area is a long rectangle running north and south. The whole load is experienced jumpers (meaning they want to pull at 2,000 to 2,500) and they are all solos or two-ways. Uppers at 3K are light and variable and winds at 12k are 270 at 45 knots. A jump run directly into the uppers would be possible, but if the first group delays getting out because they haven’t gotten directly over the landing area, then the last people out might have difficulty getting back because there is really no wind to push them back. So, make a run so that everyone ends up the same distance west of the landing area by running due north or south offset three-tenths west. Ground speed will be slightly less than if there was no wind at altitude, but it will still be high–so very little delay between groups is necessary for good separation. As always, discuss the spacing before the door comes open. Have a plan–this should prevent many costly go-arounds. Be proactive.

When you do a crosswind jump run you will also give any gear that is cutaway a chance at landing on the airport also. If you just ran into the winds aloft over the top and the first group out had a cutaway then the gear or the jumper may land in the obstacle we discussed. By using the crosswind jump run you are utilizing most of the usable landing area instead of coming across the small axis.

As the winds change through the day or the types of loads you are flying change then adjustments will be needed to the offset. Say you have a load that is all going out as one group. Depending on how big it is will determine how far to offset. If it’s a four-way then you won’t need to offset very much because the break off will not be that wide. But if it’s a big-way (40 or more) then you really will need to consider the break off spread in the offset. Remember, the canopy fliers on big-ways usually will have pretty good forward drive so if they are a little downwind of the target they should be fine in our calm surface winds example. Discuss it with your jumpers before hand.

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