ATPase required for the post-translational delivery of tail-anchored (TA) proteins to the chloroplast. Required for the accumulation of TOC34, an essential component of the outer chloroplast membrane translocon (TOC) complex (PubMed:23167510, PubMed:28382961). Recognizes and selectively binds the transmembrane domain of TA proteins in the cytosol. This complex then targets to chloroplast, where the tail-anchored protein is released for insertion. This process is regulated by ATP binding and hydrolysis (PubMed:28382961). Monomer (PubMed:28382961). Interacts with TOC34 (PubMed:28382961). Small chloroplast and strong decrease in chlorophyll content. Defect in the accumulation of photosystem protein complexes. Defect in the accumulation of TOC34, an essential component of the outer chloroplast membrane translocon (TOC) complex, which, in turn, catalyzes the import of nucleus-encoded precursor polypeptides into the chloroplast. Belongs to the arsA ATPase family.