The discussion about dorsal fins came around the other day during some late Beta testing of the new Milviz B55 Baron with regards to stalls, spins, breaks etc. The P-51 was not the only aircraft that had directional stability /departure issues that were exacerbared by the bubble canopy, the early fitted P47 D had this issue as well, and even with the strake was subject to departure past a certain slip angle, somewher around 11 deg if I remember (within an order of magnitude or so).
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