ATP-binding RNA helicase involved in translation initiation. Part of the 43S pre-initiation complex that is required for efficient initiation on mRNAs of higher eukaryotes with structured 5'-UTRs by promoting efficient NTPase-dependent 48S complex formation. Specifically binds to the 40S ribosome near the mRNA entrance. Does not possess a processive helicase activity. {ECO:0000255|HAMAP- Rule:MF_03068, ECO:0000269|PubMed:19109895, ECO:0000269|PubMed:23706745}. This is the function of DHX29 (DExH-box helicase 29, Ensembl gene identifier ENSG00000067248).