The families of the victims, who have been briefed on the interim report, have asked for privacy from the media.
The report comes after the commission in February made an urgent safety recommendation urging the Civil Aviation Authority to carry out inspections on all 73 balloons in New Zealand.
The Masterton locals killed in the crash were pilot Lance Hopping, 53, Valerie Bennett, 70, and husband and wife Desmond and Ann Dean, aged 70 and 65.
The victims from the Wellington region were Ms Bennett's cousin Denise Dellabarca, 58; husband and wife Howard and Diana Cox, aged 71 and 63; Lower Hutt couple Stephen Hopkirk, 50, and Belinda Harter, 49; and young Wellington couple Chrisjan Jordann, 21, and Alexis Still, 19.