The fabric-covered surfaces were viewed as vulnerable, even if the main structure of this aircraft was noticeably robust. Apostolo stated of the negative coverage: "This may not have in fact been true, as the BR.20s had a metal-skinned wing and not fabric covering as claimed in the Japanese Press at the time". Amongst Japanese pilots, the aircraft was considered to possess unsatisfactory range and defensive armament; however, the first Ki-21s that entered service were not much better, except for their all-metal construction and the potential for further development when better engines became available (both types initially used two 746 kW/1,000 hp engines).