**THE TWENTY-SEVENTH MEETING OF THE**

**INFORMAL PACIFIC ATC COORDINATING GROUP**

**(IPACG/27)**

(Tokyo, Japan, 05-09 Novenber, 2007)

Agenda Item 5: Air Traffic Management (ATM) Issues

**Study on a flexible route system between Australia and Japan**

(Presented by the Civil Aviation Bureau, Japan)

> [Summary]{.underline}
>
> At the Twenty-sixth meeting of the Informal Pacific ATC Coordinating
> Group (IPACG/26), Civil Aviation Bureau, Japan (JCAB) explained the
> study to implement a flexible routes system between Australia and
> Japan.
>
> This paper presents estimation of the fuel saving and flight altitude
> assignment as a results of paper trials.

1.  **Introduction**

    1.  The flight routes between Japan and Australia are Air Traffic
        Service (ATS) routes. User Preferred Routes (UPR) has been
        introduced between Japan and Fiji since Sep. 2007.

    2.  The airlines operating between Australia and Japan are looking
        for new measures to save fuel. The JCAB, with ENRI, is
        conducting a study to estimate effects of a flexible track
        system.

    3.  Flexible routes between Narita and Sydney / Brisbane were
        computed by same method of Pacific Organized Track System
        (PACOTS). Weather data in January, August and November 2006 were
        used.

    4.  The characteristic of flexible route are compared with ATS route
        on following items:

-   Flight route deviations

-   Fuel saving

-   Flight altitude assignment

1.  **Discussion**

    1.  Major traffic between Narita and east coast of Australia is
        using B586 or A337. As for the traffic on B586, the southbound
        traffic is 38% and the northbound traffic is 43%. Other traffic
        is bound for Guam / Saipan. On the other hand, As for the
        traffic on A337, the southbound is 35% and the northbound
        traffic is 33%. Other traffic is bound for Fuji or New Zealand.
        The number of traffic on B586 is about 5 times than A337.

    2.  Flexible route bound for south is located in the east from B586
        in all season. Flexible route bound for north is almost located
        in the east from B586. However, it is sometimes used in the west
        gate, because a westerly wind is weak in August. Totally, the
        flexible route is tendency to the east of B586.

    3.  Fuel burn and flight time are improved in flexible route. For
        Narita to Sydney, 1,500lbs is reduced and 4.7 min. is reduced
        per flight. For Sydney to Narita, 1,700lbs is reduced and 5.5
        min. is reduced. The rate of reduction in January is larger than
        it in August. Total 1% is reduced. The 2,000,000 dollars is
        estimated to be reduced in a year.

    4.  When traffic volume is high, requested altitude is often not
        approved. Half of flights need to change cruise altitude.
        According to the total volume, in January or November, the
        flexible route is tendency to far from B586 so that it is
        estimated reducing altitude change.

    5.  Difference between requested altitude with assigned altitude is
        same in winter and autumn. Because the traffic on B586 is
        reduced.

    6.  In summer, difference between requested altitude with assigned
        altitude is increased. Because the northbound traffic on B586 is
        sometimes increased. However, frequency of large altitude change
        per flight decreases.

2.  **Recommendation**

    1.  The meeting is invited to note the information presented in this
        paper.

**- END -**