Truth in Nomenclature (2)

justonce breaker / justonce bar / justonce stop / etc.: Engineering jargon. A justonce in any of its forms – be it the hardline switch or insertable bus-bar that bypasses circuit overload protection, the stop valve that seals off pressure-relief valves, or the disabling of thermal trips is the manual override which permits equipment to continue operating even when doing so will result in damage to equipment, personnel, or the surrounding area – even, in its most common military applications, to the entire containing vessel.

The justonce, naturally, is intended to be used only in situations where the risks and consequences of having a given piece of equipment out of action are outweigh the risks and consequences of it failing catastrophically.

The unusual name for these devices refers to a cynical saying common in the Imperial Military Service: “Doesn’t matter what they’ve got; you can’t explode twice.”

See also: damnfool switch.

– A Star Traveler’s Dictionary

Notable Replies

  1. Avatar for ahd ahd says:

    Tagged “battleshort”?

  2. Avatar for avatar avatar says:

    Because it’s the 'verse spin on this, via the latest Atomic Rockets update.

  3. Avatar for ahd ahd says:

    Ah, so.

    One wonders at the justonce instantiations back in the days of clanks.

  4. This is a device to override any fail-safe or fail-deadly systems in the circumstance that you need that device/system right the f(YAY!)k now and don’t care about anything beyond that system working right now…repair/replacement of the system is for after the disaster.

    I.e. The Crowbar.

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