 effect extrem surfac cool boundari layer transit effect extrem surfac cool boundari layer transit investig determin combin effect surfac cool pressur gradient nose blunt surfac finish boundari-layer transit data bodi shape mach number 3 12 reynold number foot high 15x10 previou transit studi moder cool agreement predict stabil theori surfac rough rang 4 1250 microinch locat transit unaffect moder cool extrem cool advers observ paramet investig gener transit reynold number decreas decreas surfac temperatur benefici effect favor pressur gradient moder cool disappear extrem cool transit reynold number lower observ cone increas nose blunt decreas transit reynold number condit extrem cool 