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t=P*r/V=1980*735*0.8/161=7231N m*g* sin(0)+t=d*Vmax^2 d=t/Vmax^2=7231/161^2=0.2790 when dive in 45 degree, let the new equilirium speed as V: new engine thrust should be 7231*(161/V) m*g* sin(45)+t=d*V^2 3500*9.8*0.707+7231*(161/V)=0.2790*V^2 thus v^3-86918V-4172728=0 Finally, we get V=316.4m/s=1139km/h. P47D 339mph=151.6m/s when level flys at Vmax, P47D in equilirium, zero acceleratiom, all forces are balanced. t=P*r/V=2300*735*0.8/151.6=8921N m*g* sin(0)+t=d*Vmax^2 d=t/Vmax^2=8921/151.6^2=0.3882>0.2816 Obviuosly ,P47d has more air drag coefficenct due to bigger wing area. when dive in 45 degree, let the new equilirium speed as V: new engine thrust should be 8921*(151.6/V) m*g* sin(45)+t=d*V^2 6000*9.8*0.707+8921*(151.6/V)=0.3882*V^2 v^3-107089V-3483833=0 Finally, we get V=342.4m/s=1232.6km/h>1139km/h. Last edited by BlackBerry; 06-06-2012 at 02:47 PM. |
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