<xs:attributeGroup name="OperationTimeGroup">
    <xs:annotation>
        <xs:documentation xml:lang="en">Provides information for operational events for a flight leg (e.g., off-ground)</xs:documentation>
    </xs:annotation>
    <xs:attribute name="Time" type="TimeOrDateTimeType" use="required">
        <xs:annotation>
            <xs:documentation xml:lang="en"> Time or date/time an operational event happened.</xs:documentation>
        </xs:annotation>
    </xs:attribute>
    <xs:attribute name="OperationType" type="OTA_CodeType" use="required">
        <xs:annotation>
            <xs:documentation xml:lang="en">Type of operational event (e.g., off-ground). References the OTA Code Table OTT.</xs:documentation>
        </xs:annotation>
    </xs:attribute>
    <xs:attribute name="TimeType" use="required">
        <xs:annotation>
            <xs:documentation xml:lang="en"> Describes whether the operational event time is scheduled, estimated or actual.</xs:documentation>
        </xs:annotation>
        <xs:simpleType>
            <xs:restriction base="xs:NMTOKEN">
                <xs:enumeration value="Actual">
                    <xs:annotation>
                        <xs:documentation xml:lang="en"> The actual operation time.</xs:documentation>
                    </xs:annotation>
                </xs:enumeration>
                <xs:enumeration value="Scheduled">
                    <xs:annotation>
                        <xs:documentation xml:lang="en"> The scheduled time.</xs:documentation>
                    </xs:annotation>
                </xs:enumeration>
                <xs:enumeration value="Estimated">
                    <xs:annotation>
                        <xs:documentation xml:lang="en"> The estimated time.</xs:documentation>
                    </xs:annotation>
                </xs:enumeration>
            </xs:restriction>
        </xs:simpleType>
    </xs:attribute>
    <xs:attribute name="ReasonCode" type="OTA_CodeType" use="optional">
        <xs:annotation>
            <xs:documentation xml:lang="en">The reason attributed to a delay or cancellation.  
Refers to  OTA Code Table FDC.</xs:documentation>
        </xs:annotation>
    </xs:attribute>
</xs:attributeGroup>