In a move to tap the domestic cargo business, Indian Airlines (IA) is planning to commence its own retail courier and freight services. This was announced by Praful Patel, minister of state for civil aviation, in the Rajya Sabha today."IA proposes to convert five Boeing-727 aircraft initially into freight aircraft," he added.Both Indian Airlines and Air India have been advised to go ahead with the tendering process for IPO advisors, the minister said.