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We discovered new high-velocity components of H$_2$O maser emission in one ofthe "water fountain" sources, IRAS~18286$-$0959, which has been monitored usingthe Nobeyama 45 m telescope in the new FLASHING (Finest Legacy Acquisitions ofSiO- and H$_2$O-maser Ignitions by Nobeyama Generation) project since 2018December. The maser spectra show new, extremely high expansion velocities($>$200~km~s$^{-1}$ projected in the line of sight) components, some of whichare located symmetrically in the spectrum with respect to the systemicvelocity. They were also mapped with KaVA (KVN and VERA Combined Array) in 2019March. We located some of these maser components closer to the central stellarsystem than other high velocity components (50--200~km~s$^{-1}$) that have beenconfirmed to be associated with the known bipolar outflow. The new componentswould flash in the fast collimated jet at a speed over 300~km~s$^{-1}$ (soon)after 2011 when they had not been detected. The fastest of the new componentsseem to indicate rapid deceleration in these spectra, however our presentmonitoring is still too sparse to unambiguously confirm it (up to50~km~s$^{-1}$yr$^{-1}$) and too short to reveal their terminal expansionvelocity, which will be equal to the expansion velocity that has been observed($v_{\rm exp}\sim$120~km~s$^{-1}$). Future occurrences of such extreme velocitycomponents may provide a good opportunity to investigate possible recurrentoutflow ignitions. Thus sculpture of the parental envelope will be traced bythe dense gas that is entrained by the fast jet and exhibits spectaculardistributions of the relatively stable maser features.

FLASHING: New high-velocity H$_2$O masers in IRAS 18286$-$0959