According to the TBM 850 checklist, at 13% NG you introduce LO Idle. But before taxi all TBM 850 pilots select high Idle. I was under the impression that high idle is selected for takeoff. Anybody know why it’s different than most other turboprops where you taxi on low idle?

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    $\begingroup$ Isn't LO idle in feather, and high idle in ground Beta? You need control over blade angle so you need to be in ground Beta to taxi. $\endgroup$
    – John K
    Aug 27 at 3:54
  • $\begingroup$ @JohnK so I guess the different techniques are used by different manufactures? $\endgroup$
    – Boeing787
    Aug 27 at 4:49
  • $\begingroup$ Just about all turbo props with free turbines run in feather at ground idle and and are just inside beta mode in flight idle. Beta mode means blade angle is not controlled by the prop governor, but directly by the power lever, like a helicopter's collective. You taxi in beta, with the ability to move the prop through forward, disc, and reverse pitch to go forward or backward. $\endgroup$
    – John K
    Aug 27 at 5:11


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