SIGMA TANDEM SYSTEM OWNER’S MANUAL
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Section 3: Instructor Techniques • Chapter 3 - Freefall / Drogue-Fall 11301 - 00.00.0000
ALTITUDE AND TIME RECOMMENDATIONS
When performing tandem jumps the following altitude recommendations apply:
A. Exit above 7,500 AGL.
B. Deploy drogue within 5 seconds after exit.
C. Minimum exit altitude is 4,500 AGL (not applicable during training or probationary jumps).
D. Minimum main deployment altitude is 4,000 AGL. (5,500 AGL is recommended)
E. Reserve initiation altitude is 2,500 AGL.
A. Exit aircraft above 7500 AGL:
It is important to exit with sufficient altitude to respond to a variety of situations.
The speed and altitude lost during unstable freefall without the drogue is hard to imagine for the uninitiated Tandem
Instructor candidate. Unusual situations such as a collapsed drogue, or drogue in tow will eat up your altitude faster
than you can imagine. Refer to Section 4: Emergencies and Malfunctions, for details on the possible problems you
may encounter.
B. Deploy drogue within 5 seconds after exit:
This gives the Tandem Instructor time to feel the stability of freefall, but is before terminal velocity, saving wear and
tear on the parachute system.
If the drogue is deployed during Tandem terminal (170+MPH), and functions properly it will take approximately 10
seconds to reduce your terminal velocity to normal (120 mph). Therefore, you should wait at least 10 seconds after
deploying the drogue in this situation before you deploy the main by pulling the drogue release handle.
In other words, if you want to deploy the drogue after Tandem terminal is reached, you must allow two thousand feet
after deploying the drogue for deceleration before pulling the drogue release handle and deploying the main. This is
not to say that the system will not work if you release the drogue immediately after deploying it at Tandem terminal.
It is to say that the faster you go, the harder the openings, which will surely reduce the life of the parachute system.
Lastly, deploying the drogue approximately 5 seconds after exit will allow you time to assess a drogue malfunction
situation, thus giving you ample time to deploy the reserve before Tandem terminal has been reached.
C. Minimum exit altitude is 4500 AGL:
For the same reasons stated in (A), this is the absolute lowest you should exit. If you experienced any problem from
this altitude you would have to respond quickly and decisively to get the situation under control and still leave
sufficient time to respond to malfunction situations. These lower exit altitudes should only be reserved for the most
experienced Tandem Instructors.
D. Minimum main deployment altitude is 4,000 AGL and the recomended altitude is 5,500 AGL
This is a recommendation that should be taken very seriously. The added complexities of performing emergency
actions as well as the speed with which you will pass through the remaining 4000 feet leave little time to deal with any
other problem which may arise, such as student interference. The Tandem pair should always exit last due to this
higher planned opening altitude. This will help prevent any traffic problems with other jumpers. Remember your
AAD will “Fire” at approximately 2,000ft.
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