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Do MARD Components Require Certification (TSO)?

Published by PLI on

MARD’s or Main Assisted Reserve Deployments are a new development within the Skydiving equipment industry. They are, to say the least, controversial.

A MARD is a device which links the malfunctioned main to the reserve bag bridle. In order to safely link the malfunctioned main assembly to the reserve bridle the normal function of the reserve pilot chute must be pre-empted. To do this the MARD link must attach to the reserve bridle at the mid point. This prevents the reserve pilot chute from ending up below the mouth of the bag when the MARD link loads the bridle. It is enough that the reserve pilot chute could be dragging against the deployment direction in its new pre-empted inverted orientation but that the drag of the malfunctioned main might not be sufficient to extract the reserve bag from its container..

The malfunctioned main must provide a means of maintaining, what little drag remains within the canopy. To do this requires a cross connector. There was a time when the U.S. Navy required a cross connector on both front and rear risers for all intentional jumps. A cross connector not only maintains the drag of the malfunctioned main but controls the flailing of the released riser. The uncontrolled release of one riser allows the released half of the main canopy to invert, in the air stream, over the main pilot chute preventing it from performing its task. The main pilot chute is the last line and most important element of this drag production system. Considering the significance of the main pilot chute within this system one might wonder how a collapsible main pilot chute would figure into the deficiencies.

3-Ring systems generally can have as much as 7 inches of riser separation differential or the release of only one riser. This is common in malfunctions resulting from a lost deployment brake which loads the risers asymmetrically.

Such uncontrolled flailing can, and has caused major difficulties involving entanglement with the deploying reserve.

During the short field life of MARDs, both of the above scenarios have occurred.  

Pre-empting the TSO’d device with a non-TSO’d device is a violation of “must not interfere with the normal function of” doctrine. This doctrine has been applied to RSL’s and AAD’s, as they only provide an alternate activation method. Whereas the MARD replaces the reserve pilot chute function with the malfunctioned main and its pilot chute as a drag device to extract the bag. This constitutes an “interference with the normal function of” and makes the main assembly the “de facto” reserve pilot chute. The bag extraction function is critical to the proper operation of the deployment sequence. Together this indicates the requirement to certify the components of a MARD. Further, it could be currently construed by the FAA that the certificated manufacturers of such devices are in violation and any rigger certifying, as airworthy, such an assembly could be cited.

The components which will require certification are the main canopy, its bridle and pilot chute, as well as the components which provide the link to the main risers. Category of Certification would be as a Reserve pilot chute.

BTW, for those of you who might think this is “Sour Grapes” because we don’t have a MARD might like to know, Parachute Labs, a number of years ago, designed and tested a MARD device called the “Lariat”. The “Lariat” worked by means of a line, which went from the RSL Cross Connector to a fold in the reserve bag bridle mid-point, whose end encompassed the fold with a kind of noose or snare. If the fold straightened from the tension of the reserve pilot chute the noose released, and if it did not, the main pulled out the reserve. We found that a MARD did nothing to speed up the deployment of the reserve out of the Racer. The only thing which would significantly shorten the distance of a Racer reserve deployment would be to shorten the bridle. Even though we had a cross connector on our system we ultimately rejected the idea as too much risk for no gain along with the complexities of Certification.

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