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The presence and structure of an Orr-like inviscid mechanism is studied infully developed, large-scale turbulent channel flow. Orr-like `bursts' aredefined by the relation between the amplitude and local tilting angle of thewall-normal velocity perturbations, and extracted by means of wavelet-basedfilters. They span the shear-dominated region of the flow, and their sizes andlifespans are proportional to the distance from the wall in the logarithmiclayer, forming a self-similar eddy hierarchy consistent with Townsend'sattached-eddy model. Except for their amplitude, which has to be determinednonlinearly, linearised transient growth represents their evolution reasonablywell. Conditional analysis, based on wavelet-filtered and low-pass-filteredvelocity fields, reveals that bursts of opposite sign pair side-by-side to formtilted quasi-streamwise rollers, which align along the streaks of thestreamwise velocity with the right sign to reinforce them, and that theypreferentially cluster along pre-existing streak inhomogeneities. On the otherhand, temporal analysis shows that consecutive rollers do not formsimultaneously, suggesting that they incrementally trigger each other. Thispicture is similar to that of the streak-vortex cycle of the buffer layer, andthe properties of the bursts suggest that they are different manifestations ofthe well-known attached Q$_2$-Q$_4$ events of the Reynolds stress.

Momentum transfer by linearised eddies in channel flows