Helmet-Mounted Displays: - USAARL - The - U.S. Army

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Joseph R. Licina
operational use or maintenance. In view of the Army’s current reduction
of manpower assets, it behooves an HMD developer to minimize such
restricting requirements. And, as the Army has a philosophy of not
excluding personnel from specific assignments due to anthropometric
considerations. Therefore, the HMD helmet dimensions must not exclude
any significant portion of the aviator population. Anyone involved in the
evolution of HMD systems in the past have found fitting to be a very soft
skill that is perishable if not repeated on a semi-routine basis. Knowledge
of head and face anthropometry must be gained before proper articulated
fitting can be accomplished. Fitting requirements, to include specialized
skills and equipment, must be minimized as the Army has resisted the
establishment of a full time military occupational specialty for aviation life
support equipment (ALSE) personnel. Under the existing system of an
additional skill identifier, ALSE personnel routinely only spend one
assignment in ALSE, then return to their primary military occupational
specialty to maintain currency for advancement in the rank. This severely
affects fitting skill quality and, invariably, the quality of provided fits.
Maintenance
Because advanced HMDs incorporate potentially fragile optical and
electronic components and require that an optical alignment, needed for
viewing and targeting, be maintained, they require increased care in their
day to day handling (Rash and Martin, 1988). The field environment in
which they operate, coupled with their constant daily usage, subject them
to normal wear and tear and occasional abuse. The normal field operational
environment experienced by Army aviators may be much harsher than that
of any of the other military services. Keep in mind that all Air Force and
Navy/Marine assets operated from fixed sites or airfields during our last
conflicts. The U.S. Army aviation units were forward deployed out of
desert sites with no fixed base support to allow for general environmental
protection of equipment. Today, in the Bosnian operation, Army aviation
assets do not enjoy the same fixed base facilities of the sister services. In
order to be acceptable to the military aviation community, HMDs must be
able to perform their intended functions without being degraded by normal
usage. When failure does occur, repairs need to be accomplished at the
lowest maintenance level possible. Where feasible, modular replacement
as a maintenance approach is critical.
A formal field maintenance program is essential for the fielding of
sophisticated HMDs. Developers must identify critical components and