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tokens: and is very likely a few degrees. Thus in total we see that the observed bend is ∼70° at angle θ ≈ φ int /1.4. In other words, an intrinsic bend in the jet of only a few degrees will produce the overall projected bend in the jet axis of ∼70° that we see in Figure 4 (c) when viewed from within a few degrees of the jet axis. Of course, the observed bend angle tends to 180° as θ → 0. The simplest possible bending model is a monotonic bend that lies all in a single plane, as assumed above. Given a small viewing angle near the base of the jet, this would normally result in an apparent one-sided jet, due to the strong Doppler boosting of the approaching jet emission and de-boosting of the receding jet emission. The approaching jet would also rapidly fade with distance from the core as the viewing angle increases. However, if the bending plane lies perpendicular to the sky, the jet can cross our line of sight, resulting in apparent emission from the approaching jet on both sides of the core. Statistically, the odds of this alignment appear at first to be low, but in a flux-limited AGN sample, there is a strong preference for those jets that have maximum Doppler boosting factor. The latter occurs when a portion of the jet is pointing directly at us, which is the case for a jet crossing our line of sight. Lister ( 1999 , p99) showed that in fact a simple parabolic bent jet will have a total apparent flux density much larger than a straight jet with identical inner jet viewing angle, provided the bending occurs in a plane nearly perpendicular to our line of sight. One notable case of this azimuthal favoritism is the blazar PKS 1510−089, where Homan et al. ( 2002 ) provide strong evidence of a highly superluminal jet that makes a 180° apparent bend in the sky plane, with resulting collinear jet emission on either side of the AGN core. We do therefore have to consider the possibility that all of the radio emission seen in this blazar is associated with the jet, but just happens to appear to straddle the nuclear core due to projection effects. One clear difference between the radio structures of PKS 1413+135 and PKS 1510−089 is the inner counterjet component C in PKS 1413+135 seen in Figures 4 (c)–(f). An even closer component of the inner counterjet, which is connected to the core component, is seen in the 8.1 GHz and 23.8 GHz images of Figure 5 . No such inner counterjet, close to the core, is seen in PKS 1510−089, and it is very hard to imagine that these two components close-in to the core, which are so well aligned with the jet position angle projected across the core, are actually components of the approaching curving jet that have been projected across the core to the counterjet side after the approaching jet curves through an apparent bend of ∼70° from components N through G as seen in Figure 4 (c). There is also the surface brightness of the components to consider. The components within 10 mas on the northeast side of the core have much higher