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I recently rode in the jumpseat of an A330 during a flight. Quickly after touchdown, the PF selected idle reverse, and no further. As soon as he did so, I could hear the engines begin to spool up, and saw the EPR indications rise, before the engines went back to idle reverse about 3 seconds later. My question is, do the engines automatically begin to spool up as soon as idle reverse is selected in order to more rapidly provide maximum reverse thrust if that setting is subsequently selected?

If so, this is unusual, as all other engines will remain in idle until further reverse thrust is selected. I looked in the FCOM and FCTM, and asked the pilot flying himself, but could get no answer. The engines were Rolls-Royce Trent 700s.

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  • $\begingroup$ When you pull the reverse levers up there is a physical detent or stop for idle reverse. It's easy to overshoot the idle detent or stop, so the engines get a short small reverse thrust input that then goes back to idle, as you pull them up, overshoot a bit, then ease them down into the detent or stop. $\endgroup$
    – John K
    Nov 4, 2022 at 15:03
  • $\begingroup$ @JohnK On the A320 the reverse levers will actually only get you into idle reverse, you then have to pull the main thrust levers backwards for more reverse thrust. But on the A330 Airbus went back to the more traditional design (with a detent for reverse idle) for some reason. $\endgroup$
    – Bianfable
    Nov 4, 2022 at 15:36
  • $\begingroup$ Sounds like the 320 was an attempt to replicate turboprop power lever operation maybe, for pilots moving up from TPs. On the CRJ200, the reverse idle detent was very difficult to find on the way up, and you'd almost always overshoot a bit. Fortunately, the screwjack driven cascade reversers took about a week to deploy, so it didn't matter so much. $\endgroup$
    – John K
    Nov 5, 2022 at 2:09
  • $\begingroup$ To anyone who is interested, I found the answer. When idle reverse is selected, it will enter "elevated idle" mode for a few seconds to more quickly provide full reverse if that setting is selected. If the reverse thrust levers stay in the idle reverse detent, however, they will change to "normal idle" mode from "elevated idle" mode. This applies to the A330-200 with RR engines, don't know if it applies to other variants. Found it in the FCOM. $\endgroup$ Nov 5, 2022 at 11:46

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To anyone who is interested, I found the answer. When idle reverse is selected, it will enter "elevated idle" mode for a few seconds to more quickly provide full reverse if that setting is selected. If the reverse thrust levers stay in the idle reverse detent, however, they will change to "normal idle" mode from "elevated idle" mode. This applies to the A330-200 with RR engines, don't know if it applies to other variants.

Found it in the FCOM:

Reverse idle

Minimum reverse idle:

The minimum reverse idle setting is the nominal idle mode when thrust reverser lever is at the reverse idle detent (de-activated when elevated reverse idle is active). The FADEC selects the minimum reverse idle setting when:

  • The aircraft is on ground
  • The flight crew selects the reverse thrust, via the thrust reverser lever.

Elevated reverse idle:

The elevated reverse idle setting enables to rapidly accelerate the engine from reverse idle to maximum reverse thrust. This mode is only available for the first seconds of thrust reverser deployment and is higher than minimum reverse Idle.

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