KAPE Boatworks recommends using lifting straps (slings) for launching or hauling out the Martin 16 with a crane.
Straps are available from Hercules SLR. See www.herculesslr.com to find a distributor near you.
The part number is EE2902322PN. The cost is approximately CAN$60 for a pair of straps.
2 inches in width by 22 feet in length.