Table of Equivalent Velocities.
| Miles per Hour. | Feet per Second. | Feet per Minute. | Metres per Minute. | Metres per Second. | |||
|---|---|---|---|---|---|---|---|
| 1, | 1 | ·5 | 88 | 26 | ·8 | ·447 | |
| 2, | 2 | ·9 | 176 | 53 | ·6 | ·894 | |
| 3, | 4 | ·4 | 264 | 80 | ·5 | 1 | ·341 |
| 4, | 5 | ·9 | 352 | 107 | ·3 | 1 | ·788 |
| 5, | 7 | ·3 | 440 | 134 | ·1 | 2 | ·235 |
| 6, | 8 | ·8 | 528 | 160 | ·9 | 2 | ·682 |
| 8, | 11 | ·7 | 704 | 214 | ·6 | 3 | ·576 |
| 10, | 14 | ·7 | 880 | 268 | ·2 | 4 | ·470 |
| 15, | 22 | 1,320 | 402 | ·3 | 6 | ·705 | |
| 20, | 29 | ·4 | 1,760 | 536 | ·4 | 8 | ·940 |
| 25, | 36 | ·7 | 2,200 | 670 | ·5 | 11 | ·176 |
| 30, | 44 | 2,640 | 804 | ·6 | 13 | ·411 | |
| 35, | 51 | ·3 | 3,080 | 938 | ·8 | 15 | ·646 |
| 40, | 58 | ·7 | 3,520 | 1,072 | ·9 | 17 | ·881 |
| 45, | 66 | 3,960 | 1,207 | 20 | ·116 | ||
| 50, | 73 | ·4 | 4,400 | 1,341 | ·1 | 22 | ·352 |
| 60, | 88 | 5,280 | 1,609 | ·2 | 26 | ·822 | |
| 70, | 102 | ·7 | 6,160 | 1,877 | ·5 | 31 | ·292 |
| 80, | 117 | ·2 | 7,040 | 2,145 | ·8 | 35 | ·763 |
| 90, | 132 | 7,920 | 2,414 | 40 | ·233 | ||
| 100, | 146 | ·7 | 8,800 | 2,682 | ·2 | 44 | ·704 |
| 110, | 161 | ·2 | 9,680 | 2,950 | ·2 | 49 | ·174 |
| 120, | 176 | 10,560 | 3,218 | ·4 | 53 | ·644 | |
| 130, | 191 | 11,440 | 3,486 | ·6 | 58 | ·115 | |
| 140, | 205 | ·3 | 12,320 | 3,755 | ·1 | 62 | ·585 |
| 150, | 220 | 13,200 | 4,023 | ·3 | 67 | ·056 | |
To convert feet per minute into
metres per second, multiply by ·00508.
Table Showing Velocity and Thrust Corresponding with Various Horse-Powers.
| Velocity in Miles per Hour. | Horse-Power. | |||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 10 | 20 | 30 | 40 | 50 | 60 | 70 | 80 | 90 | 100 | ||||||||||||
| Thrust in Pounds. | ||||||||||||||||||||||
| 1, | 375 | 3,750 | 7,500 | 11,250 | 15,000 | 18,750 | 22,500 | 26,250 | 30,000 | 33,750 | 37,500 | |||||||||||
| 5, | 75 | 750 | 1,500 | 2,250 | 3,000 | 3,750 | 4,500 | 5,250 | 6,000 | 6,750 | 7,500 | |||||||||||
| 10, | 37 | ·5 | 375 | 750 | 1,125 | 1,500 | 1,875 | 2,250 | 2,625 | 3,000 | 3,375 | 3,750 | ||||||||||
| 15, | 25 | 250 | 500 | 750 | 1,000 | 1,250 | 1,500 | 1,750 | 2,000 | 2,250 | 2,500 | |||||||||||
| 20, | 18 | ·8 | 187 | ·5 | 375 | 562 | ·5 | 750 | 937 | ·5 | 1,125 | 1,312 | ·5 | 1,500 | 1,687 | ·5 | 1,875 | |||||
| 25, | 15 | 150 | 300 | 450 | 600 | 750 | 900 | 1,050 | 1,200 | 1,350 | 1,500 | |||||||||||
| 30, | 12 | ·5 | 125 | 250 | 375 | 500 | 625 | 750 | 875 | 1,000 | 1,125 | 1,250 | ||||||||||
| 35, | 10 | ·7 | 107 | ·1 | 214 | ·3 | 321 | ·4 | 428 | ·6 | 535 | ·7 | 642 | ·8 | 750 | 857 | ·1 | 964 | ·3 | 1,071 | ·4 | |
| 40, | 9 | ·4 | 93 | ·8 | 187 | ·5 | 281 | ·3 | 375 | 468 | ·8 | 562 | ·5 | 656 | ·3 | 750 | 843 | ·8 | 937 | ·5 | ||
| 45, | 8 | ·3 | 83 | ·3 | 166 | ·7 | 250 | 333 | ·3 | 416 | ·7 | 500 | 583 | ·3 | 666 | ·7 | 750 | 833 | ·3 | |||
| 50, | 7 | ·5 | 75 | 150 | 225 | 300 | 375 | 450 | 525 | 600 | 675 | 750 | ||||||||||
| 60, | 6 | ·3 | 62 | ·5 | 125 | 187 | ·5 | 250 | 312 | ·5 | 375 | 437 | ·5 | 500 | 562 | ·5 | 625 | |||||
| 70, | 5 | ·4 | 53 | ·6 | 107 | ·1 | 160 | ·7 | 214 | ·3 | 267 | ·9 | 321 | ·4 | 375 | 428 | ·6 | 482 | ·1 | 535 | ·7 | |
| 80, | 4 | ·7 | 46 | ·9 | 93 | ·8 | 140 | ·6 | 187 | ·5 | 234 | ·4 | 281 | ·3 | 328 | ·2 | 375 | 421 | ·9 | 468 | ·8 | |
| 90, | 4 | ·2 | 41 | ·7 | 83 | ·3 | 125 | 166 | ·7 | 208 | ·3 | 250 | 291 | ·7 | 333 | ·3 | 375 | 416 | ·7 | |||
| 100, | 3 | ·75 | 37 | ·5 | 75 | 112 | ·5 | 150 | 187 | ·5 | 225 | 262 | ·5 | 300 | 337 | ·5 | 375 | |||||
Fig. 72b.—When an aeroplane is driven through the air, it encounters stationary air and leaves it with a downward trend. With a thick curved aeroplane, as shown, the air follows both the top and the bottom surfaces, and the direction that the air takes is the resultant of these two streams of air. It will be seen that the air takes the same direction that it would take if the plane were flat, and raised from a to c, which would be substantially the same as shown at f, h, g. It has, however, been found by actual experiment that the curved plane is preferable, because the lifting effect is more evenly distributed, and the drift is less in proportion to the lift.
