1 78 AEROPLANE PERFORMANCE CALCULATIONS 



Example (2). Getting off the Ground. For the same 

 machine, the length run in still air in feet is 

 1-151 x 5700F , / 175*0 \ i/5'O 



-WH 10g " (.75-0 + 66-6) + logl V. 7 5-o - 66- 6 )J 



= 258 feet 



Example (3). Landing on a Deck. With the same ship 

 speed and the same machine, R x + R 2 = 510, k imax = '590, 

 S = 695, L/D = 8-05 when \ = i -o. 



... K = -001495 x 510 + -0/625 XQO x 695 == 



The slowest flying speed has been worked out for the machine 

 we are dealing with in example (12), Chapter XIX., Part III., 

 page 174. 



/. V m = 48-5- 



Also as before V w = 32-0. Therefore the length run on 

 alighting, measured in feet along the deck is 



Example (4). Landing on the Ground. Take the same 

 machine landing on the ground in a calm, and assume that brakes 

 on the wheels (if any) and tail skid friction on the ground are 

 estimated by giving a value of -04 to /z. Suppose that the 

 machine is flown, not glided, down to the landing, then again 

 V m = 48-5. As before K = 4-646 



_ 4J646 _ '4-95 x -04 _ 6l 



5700 48-5" 



Then the length of run in feet, for the value of /t assumed, is 



ri 5' lo glo (- 4-646 x 4 8- 5 J_\ . feet 



000561 \I4'95 x 5700 x -047 



