From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Comparison of horsepower required and power savings for streamlined vs. conventional highway and rail vehicles.
| Identifier | ExFiles\Box 161\1\ scan0018 | |
| Date | 31th May 1936 guessed | |
| 3. H.P. REQUIRED FOR OVERCOMING AIR RESISTANCE TABLE 1 (Fig. 4) | TYPE OF EQUIPMENT | | | A | K | Miles per Hour | |---|---|---|---|---|---|---|---|---|---| | | | | | | 60 | 50 | 40 | 30 | 20 | | Highway Bus | 1 | Streamline | 64 | .0006 | 22 | 12.8 | 6.5 | 2.8 | 0.8 | | | 2 | Conventional | 72 | .0015 | 63 | 36 | 18 | 7.8 | 2.3 | | Highway Truck | 3 | Streamline | 86 | .001 | 50 | 29 | 15 | 6.3 | 1.8 | | | 4 | Conventional | 92 | .0016 | 85 | 52 | 25 | 10.6 | 3.1 | H.P.A = KAV^3 / 375 K = Air Resistance Coefficient A = Sq. Ft. Frontal Area V = Miles per Hour Fig. 4. The following table, Fig. 5, shows the cost of overcoming air resistance for a period of 1000 hours in four types of streamlined and conventional railroad equipment, using a power cost figure of 1 cent per horsepower hour. POWER SAVINGS BY STREAMLINING RAIL EQUIPMENT Per 1,000 Hours @ $0.01 Per H.{Arthur M. Hanbury - Head Complaints} P. H.{Arthur M. Hanbury - Head Complaints} TABLE 2 (Fig. 5) | TYPE OF EQUIPMENT | | | Average V | A | K or KT | H.P.H. | Dollars per 1000 Hrs | Saving per 1000 Hrs. | |---|---|---|---|---|---|---|---|---| | Rail Car | 1 | Streamline | 52 | 96.2 | .00059 | 29074 | 290.74 | 544.50 | | | 2 | Conventional | 52 | 125 | .00134 | 83524 | 835.24 | | | Three Car Train | 3 | Streamline | 52 | 108 | .00087 | 43225 | 432.25 | 2110.71 | | | 4 | Conventional | 52 | 125 | .00408 | 254296 | 2542.96 | | | Six Car Train | 5 | Streamline | 52 | 108 | .0019 | 102277 | 1022.77 | 2138.64 | | | 6 | Conventional | 52 | 125 | .0051 | 316141 | 3161.41 | | | Freight Container Car | 7 | Streamline | 45 | 103.5 | .0009 | 30058 | 300.58 | 175.56 | | | 8 | Conventional | 45 | 125 | .0017 | 47614 | 476.14 | | Fig. 5 Comparisons in the above tables are based on approximately existing operating speeds for highway service whereas the speeds shown in the rail service | ||