CoolIP index                                                          Most recent edit: Wednesday October 24, 2012

* See legal note below.

Solution to FAA-Required Tether Conspicuity for Crosswind AWES

The FAA requires that a tether be conspicuous the flying public by day or night. AOPA, EAA, and NAAA have all lined up to demand this standard be enforced. Any AWES development team unable to comply is unlikely to advance against this combined opposition.

Crosswind AWES seems rather disadvantaged, as the requirement entails large FAA-orange-and-white banners and marking FA-red lights of a minimum brightness every fifty feet of tether. Virtually every crosswind team responding to the FAA question over AWES conspicuity expressed a problem with either the added tether aerodrag or how these devices will meet power-needs or cope with winching.

A KiteLab Group solution to the single-line crosswind case is sweeping stacks of wings, an orange or white wing every 50 ft, with an embedded RAT to drive the lighting. Required conspicuity thus becomes naturally easy and even exceedable. A stack of wings generally develops far more power than a single wing. Stacks have been long known in sport-kite circles as a powerful standard configuration. The wings could stack and unstack at the ground by gripping or releasing* (or hanking on and off) the tether as it is extended or retracted from its winch.

Thus the aviation conspicuity "problem" is converted into a synergistic virtue.

* A trick common to legacy cable cars

CoolIP*                      ~Dave Santos                 7Eeb2012                     AWES5594

Comment and development of this topic will be occurring here.       
All, send notes, drawings, and photographs!

Terms and aspects:   

  • aerodrag
  • working markers

Related links and concepts:

Commentary is welcome:

  • Yeah,
    I see no problem with compliance to that visibility standard for a dense stack of rotating rings.

    As for the cable car type clamping... inspiration from that thought thanks Dave.

    I don't remember ever having considered using tether clamping radially on the outside or inside edge of the ring bag. Doh
    It has so many obvious advantages for rigging, launching and recovery.

    And could in all probability, with enough gizmo, be done on a live spinning system.
    ~Rod Read
  • Roddy,
    As for clamping on a line with COTS, sailing hardware is our obvious expedient, there are plenty of cam cleats, clam cleats, clutches, and jammers to choose from; the simplest light ABS plastic types are particularly suitable and cheap. In combination with preventer stoppers, shackles, and/or kite-killers, this is a very optimal method.

    The current kiter's low tech method is to wrap the kiteline about eight times around an Alu carabiner to attach junk, but this is hard to do under tension. KiteLab Ilwaco has developed simple bent wire line attachment hardware suited for small systems. These work and are more handy and far cheaper than 'biners.

    The Alpine Butterfly Knot is good for adding attachment loops on a line; the high safety margin required for line nicks allows for the small loss of breaking strength the knot introduces, (replace nicked or abraded sections as they are found, as they act progressively; a quick fix is to tie a Butterfly to isolate damage on the loop created).

    KIS is King,
    Dave Santos
  • Thanks, DaveS
    Bunny ears is my favourite fun to tie and use knot ... must use it in my kite repertoire.
    A prussic or a rolling hitch could be used in a similar fashion..  ~Rod Read

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