The Black Diamond ATC XP is a belay device based upon the trustworthy ATC with the notable exception of having additional friction ridges cast into one side of the device.  These ridges offer more control over the person being belayed by allowing the belayer to lock own the rope with very little effort in the event the climber should fall.  There are many rappel devices that look and function similar to the ATC XP and I don’t really know who pioneered this design but for the sake of keeping it practical (and simple), most of the belay/ rappel devices of this design will have similar characteristics.  Since this is a Canyoneering post, we will look at the ATC XP as a rappel device. 

     This unit has basically four modes of use: single line high friction, single line low friction, double line high friction, and double line low friction.  In the high friction mode, the friction ridges will be on the tail side of the rope allowing the person on rappel to pull the rope into the ridges to control the descent as necessary.  In the low friction mode (with the ridges facing away from the tail of the rope), it is much the same as a traditional ATC.  Since the design of this product is based on rock climbing, use of any rope thicker than ten millimeter will result in a very slow – if not painfully slow – descent.  For this reason, our evaluation will be done with Sterling Ropes HTP super static in 9mm.  This is a polyester sheath/ polyester core dry treated rope that works well with Canyoneering.  For the ease of photos, I have opted not to show it in double line configurations.

     In single strand high friction mode, this device is among the easiest to manage.  The descent is extremely controllable and little strength is needed to stop.  This is my preferred rappel device to use with new Canyoneers as it’s high friction and slow predictable descent characteristics can help calm quivering knees. 

     If you want to speed up your descent and add a bit of versatility, simply flip the device on the carabiner and feed the rope through In single strand low friction mode.  The device becomes noticeably faster yet control seems to be a bit smoother (see summary).  Canyoneers that anticipate being in a cold waterfall might appreciate this mode of operation as you can move a little more quickly when you need to maneuver behind or around rushing water quickly while still maintaining full control. 

            Summary:  Overall I really like this little device.  It is an excellent choice for beginners as the high friction mode takes little strength to maintain total control of the rope.  The only issue with this device is when using the high friction setting, it is sometimes hard to find the “sweet spot” when feeding the rope into the device.  Because of the great grip on the rope, you have to give a little more slack than with other devices to get moving, then the device takes up the slack a little quicker than you might be feeding it and the rope sinks into the friction ridges again causing you to bounce slightly.  This is more noticeable on ropes with higher static elongation properties (above 7%).  The cable that comes molded with the device is a nice touch, however if you don’t pay attention to the ATC XP while you are coming off the rope, it is still easy to lose.  Some canyoneers I know will tie a small section of thin cord to the cable of the ATC XP to make sure they don’t lose it.  I generally don’t advise this as there is enough to keep track of near your rappel device and another cord is an un-necessary risk of tangling.  Still, the control offered by this device has earned it a place on my harness as a competent rappel device and an excellent choice for novices as well.