 The XP-15 had a split-axle undercarriage and a tail wheel.Boeing numbered the craft as its "Model 202"; while the United States Army accepted it for testing and designated it as XP-15, they never actually purchased it, and it retained its civil registration of X-270V.The XP-15 first flew in January 1930, when it was discovered that the vertical stabilizer (a P-12C type) needed to be larger in order to compensate for the single wing.