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Stability analysis on a supersonic natural laminar flow (NLF) wing designed by JAXA was performed at both flight and wind tunnel test conditions as a joint research program between ONERA and JAXA. Both parties validated the NLF wing effect by confirming suppression of crossflow instability at design point, using an e(N) method with fixed β strategy proposed by ONERA. Although JAXA’s flight test vehicle and wind tunnel test model had almost same averaged roughness height of about 1micrometer, it was shown that surface roughness had little influence on measured transition location at both flight and wind tunnel test conditions. Furthermore, JAXA found that the pressure distribution measured in flight test did not completely coincide to the target pressure distribution (Cp (Target)) for the NLF wing design. It revealed that measured transition location at outer wing region was not delayed in flight test, compared with the transition location predicted with the Cp (Target) which had large gain to delay the transition. Influence of Reynolds number on transition location was also studied for the target pressure distribution Cp (Target). Consequently, chordwise transition location, (x/c)Tr., rapidly moves from mid-chord location to forward location (near leading edge) for increasing Reynolds numbers, according to the change of instability of boundary layer from Tollmien-Schlichting instability to crossflow instability., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, 資料番号: AA0062081000, レポート番号: JAXA-RR-12-009E