~  ... I-’  ... J.,  t-:)  0  ~  0  ~  al  ~  TABLE  I .-Airship model characteristics and  data-Continued  Area  Prandtl shape coefficient  Fin&- Dis- .  Pris- maxi- ness  tanoo  Dis- matic  mum  CD  ratio,  maxi- tan co  coom- Lenzth•  Diame- Surface,  Volume,  Name of model  cross- FR  mum  CG  cient,  ter,  D  8  sectional  Vol.  L  diameter  from  Q  Vol.  area  20  10  60  ~- ·  from  nose  D  -A-L  A  m. p. b.  m. p. b.  m. p. b.  nose  - - - -• • •- - - . EUiptical series (British)  Feet  Feet  Sq.  ft.  Sq.  ft.  Cu.  ft.  P.ct.L  P.ct. L  E  ~ ---------------- --- - 2. 371 0. 3906 ------- 0. 120 0. 1658 0. 0132 0. 0135 -- ---- 6. 070 33. 19 ------ 0 5835 E 2- --- --------------- 1. 743 . 3910 --- -- -- . 120 . 1261  . 0138  . 0128  ------ 4. 460 33. 86 . 6024  E 3------------------- 1. 568 •  3920 ------- . 121  . 1112 . 0147  . 0120  ----- - 4. 000 34. 19 ----- - . 5876 E4 _____________ ___ ___  1. 384 •  3923 ---- --- . 121  . 0972 . 0167  $^{. 0139 }$-- ---- 3. 500 35. 18 ------ . 5810 E 5------------------- 1. 178 •  3929 ------- . 121  . 0826 ’  . 0184  . 0147 ------ 3. 000 33. $^{43 }$------ . 5786 Parabolic series (British)  p  } ____________ ____ ___  1. 594 . 3900 --- ---- . 120  . 0970 . 0168 . 0137 ------ 4. 090 49. 39 ------ . 5094 P2  ______________ ____ _  1. 598 . 3903 ------- - 120 . 1000 . 0169 . 0176 4. 070 32. 06 - ----- . 5265 Pa ________ __ _______ __  1. 173 . 3867 . 117 . 0729 . 0226 . 0173 ----- - 3. 830 50. 35 ------ . 5293 P4------------------- 1. 217 $^{. 3870 }$------- . 118 •  0714 . 02-15  . 0193 ------ 3. 140 35. 05 . 4989 - --•••- -------------------------- -••- - ---- --------------- Index of form efficiency  Q  H,- - CD  20  40  eo  m.p.h.  m. p.h.  m. p.  11.  - - 44. 20 43. 22 ------ 43. 65 $^{47. 06 }$------ 40. 00 45. 55 -- ---- 34. 79 41. 80 - ----- 31. 45 39. 36 -- ---- 30. 32 37. 18  ----- - 31. 15 30. 00 - ----- 23. 42 30. 60  ------ 23. 20 25. 85 -- ---- •••---------------- --- ----