Question

How much horsepower would a vehicle need to tow the SS Delphine up the industry standard: Davis Dam Grade Climb?

• Davis Dam assumed grade = 7%
• Air density is sea level conditions (.002377 slugs/f^t3)
• w(weight) of the SS Delphine + trailer + Redeye = 3,922,000 + 150,000 + 4451 Lbs
• Crr = coefficient of rolling resistance = .015
• Assume Combined CDA is 1555 ft^2
• SAE J2807 (Davis Dam Grande Climb) - min speed is 40mpg (59 ft/s)
• F(drag) = 1/2p x V^2 x C(d)A
• F(rolling resistance) = W x cos x Crr
• F(weight) = W x sin
• F(sum) = F(drag) + F(rr) + F(weight)
• P = F(sum)XV
• convert to horsepower = P(1hp/550ft lbf/sec)

Answer 1