**DATA ITEM DESCRIPTION**

**Title:** Human Engineering Design Approach Document-Operator (HEDAD-O)

**Number:** DI-HFAC-80746B **Approval Date:** 08 July 1998

**AMSC Number:** A7320 **Limitation:** N/A

**DTIC Applicable:** No **GIDEP Applicable:** No

**Office of Primary Responsibility:**

**Applicable Forms:** N/A

**Use/relationship:**

The Human Engineering Design Approach Document-Operator (HEDAD-O)
describes equipment which interfaces with operators. This document
provides a source of data to evaluate the extent to which equipment
having an interface with operators meets human performance requirements
and human engineering criteria.

a.  This Data Item Description (DID) contains the format and content
    preparation instructions for HEDAD-O resulting from applicable tasks
    delineated in the SOW.

b.  This DID supersedes DI-HFAC-80746A.

**Requirements:**

1.  [Reference documents]{.underline}. The applicable issue of the
    documents cited herein, including their approval dates and dates of
    any applicable amendments, notices, and revisions shall be as cited
    in the current issue of the DODISS at the time of the solicitation.

2.  [General]{.underline}. The HEDAD-O shall describe the layout, detail
    design, and arrangement of crew station equipment having an
    operator. Interface; it shall also describe operator tasks (see
    below) associated with equipment. The HEDAD-O shall describe the
    extent to which human performance requirements and applicable human
    engineering design criteria (e.g., MIL-STD-1472) have been
    incorporated into the layout, design, and arrangement of equipment
    having an operator interface. Findings from analysis of operator
    tasks shall be presented as part of the rationale supporting the
    layout, design, and integration of crew station equipment.

3.  [Format.]{.underline} The HEDAD-O format shall be contractor
    selected. Unless effective presentation would be degraded, the
    initially used format arrangement shall be used for all subsequent
    submissions.

4.  [Content]{.underline}. The HEDAD-O shall contain the following crew
    station and operator- related information:

    a.  [Equipment List]{.underline}. A list of each item of equipment
        having an operator interface and a brief statement of the
        purpose of each item of equipment. Separate lists shall be
        provided for each operator's station.

    b.  [Specification and drawing list]{.underline}. A list of
        specifications and drawings, approved by human engineering at
        the time of HEDAD- O preparation. When contractually required to
        prepare and submit the HEDAD-O early in the development process,
        the list shall also address documents where human engineering
        approval is planned.

    c.  [Crew station and Drawing List]{.underline}. Description(s) of
        the crew station(s), emphasizing human engineering design
        features. The following aspects of each crew station shall be
        described:

        1.  [Layout and arrangement.]{.underline} One sketch, drawing,
            or photograph of each crew station. These sketches,
            drawings, or photographs shall contain operator and
            equipment related reference points (e.g., operator eye
            position, seat reference point) and scale. One sketch,
            drawing, or photograph of each item of crew station
            equipment shall also be provided; the point of reference
            shall be normal to the item of equipment and scale shall be
            indicated.

        2.  [Controls and displays]{.underline}. The layout and detail
            design of each control/display panel (or control/display
            areas independent of panels) shall be described (e.g.,
            phosphor type, brightness, resolution, contrast, color or
            other coding, control/display ratio, control force, and
            range characteristics). Display symbology, display formats,
            and control/display operation logic shall be described with
            regard to intended use by the operator(s).

        3.  [Operator vision]{.underline}. Operator vision to crew
            station items of equipment shall be described using the
            operator's normal eye position(s) as the point of reference.
            When applicable, operator external vision shall also be
            described using the operator's normal eye position(s) as the
            point of reference; extent of external vision shall be
            related to system mission requirements.

        4.  [Environmental Factors.]{.underline} Operator life support
            systems, protective clothing and equipment, noise vibration,
            and other relevant environmental perimeters.

        5.  [Ingress/ egress.]{.underline} Normal and emergency ingress
            and egress provisions and procedures

        6.  [Crew station lighting]{.underline}. Crew station lighting
            characteristics and lighting control system.

        7.  [Crew station signals]{.underline}. Crew station signals
            including warning, caution, and advisory signals shall be
            described with regard to signal characteristics, signal
            meaning, signal consequences, operator .procedures, cause of
            signal activation, and crew control over signal
            characteristics.

        8.  [Operator posture control]{.underline}. Operator posture
            control including seating, restraint systems, and other
            postural control techniques.

        9.  [Communication System.]{.underline} Communication system and
            communication system control.

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10. [Special Design]{.underline}. Special design, layout, or arrangement
    features if required by mission or system environment.

11. Multiple operator stations. Multiple operator station design, shall
    be described where applicable. Rationale for number of operators,
    arrangement of operators, and allocation of functions to the
    operators shall also be described.

    a.  [Crew station geometry]{.underline}. Crew station geometry shall
        be described using the seat reference point or operator's eye
        position(s) as a reference Point" The Position 'f 'ach control
        display, panel, etc., shall be described in terms of three
        dimensional space (X, Y, Z coordinates); operator eye position
        shall be described in terms of system design coordinates or as
        zero (X), zero (Y), and zero (Z). The center of each panel,
        display, control, etc., shall be used as the equipment point of
        reference. True angle to vision to each item of equipment shall
        also be shown.

    b.  [Human engineering design rationale]{.underline}. Engineering
        design, layout, and arrangement of station equipment having an
        operator interface Rationale for human each item of crew shall
        be described. The specific considerations of system mission (or
        system function); equipment operation; operator selection,
        training, and skill requirements; operator task performance
        requirements; and limitations imposed on designs by the
        procuring activity or state-of-the-art shall be described. The
        basis for reaching specific design, layout, and arrangement
        decisions shall be presented (e.g., MIL-STD-1472 criteria, human
        engineering requirements or guidelines specified in the
        contract, system engineering analyses, systems analyses, human
        engineering studies, trade-off analyses, mock-up results,
        simulation results, and human engineering results).

    c.  [Analysis of operator tasks]{.underline}. Results from analysis
        of operator tasks (see critical tasks in MIL-HDBK-1908) shall be
        presented as part of the rationale for crew station design,
        integration, and layout. The following shall also be described:
        methodology used to generate task analysis results (e.g., paper
        and pencil, computer-based simulation, dynamic simulation);
        system-mission(s), function(s), or other exogenous information
        used to "drive" the task analysis; human performance data (e.g.,
        time and error) against which task analysis results are
        compared; and operator assumptions (e.g., level of skill,
        training). Critical tasks (see MIL-HDBK-1908) shall be clearly
        identified. If the program has progressed to the point where the
        required data is available through other reporting media, such
        as a task inventory or task analysis, they shall not be
        duplicated, but shall be referenced or appended to" the HEDAD-M
        along with appropriate supplemental' information fulfilling the
        intent of this provision.

    d.  [Alternatives to baseline design]{.underline}. Sketch, drawing,
        or photograph of each item of equipment being considered as
        alternatives or changes to the selected (baseline) crew station
        design.

    e.  [Desktop changes]{.underline}. Design, arrangement, or layout
        changes made since the last HEDAD-O preparation.