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There appears to be a fundamental problem facing Active Galactic Nuclei jetmodels that require highly relativistic ejection speeds and small jet viewingangles to explain the large apparent superluminal motions seen in so many ofthe radio-loud quasars with high redshift. When the data are looked at closelyit is found that only a small percentage of the observed radio frequency fluxdensity from these sources can be Doppler boosted. Without a highly directed,Doppler boosted component that dominates the observed flux, radio sources foundin low-frequency finding surveys cannot be preferentially selected with smalljet viewing angles. The distribution of jet orientations will then follow thesin$i$ curve associated with a random distribution, where only a very fewsources (~1%) will have the small viewing angles (<8 deg) required to explainapparent superluminal motions v{app > 10c, and this makes it difficult toexplain how around 33% of the radio-loud AGNs with high redshift can exhibitsuch highly superluminal motions. When the boosted component is the dominantone it can be argued that in a flux limited sample only those members withsmall viewing angles would be picked up while those with larger viewing angles(the un-boosted ones) would be missed. However, this is not the case when theboosted component is small and a new model to explain the high apparentsuperluminal motions may be needed if the redshifts of high-redshift quasarsare to remain entirely cosmological.

Doppler Boosting May Have Played No Significant Role in the Finding Surveys of Radio-Loud Quasars