﻿SOARING 
  FlilGHT 
  KLEMPERER 
  239 
  

  

  lately 
  since 
  elaborate 
  surveying 
  stations 
  were 
  installed 
  on 
  the 
  

   Wasserkuppe 
  and 
  Rossitten 
  gliding 
  centers. 
  A 
  number 
  of 
  con- 
  

   tinuous 
  surveys 
  of 
  outstanding 
  flights 
  were 
  recorded 
  stereographically 
  

   and 
  evaluated 
  afterwards, 
  reconstructing 
  the 
  complete 
  path 
  of 
  the 
  

   glider 
  in 
  space. 
  This 
  work 
  was 
  originally 
  started 
  by 
  taking 
  syn- 
  

   chronous 
  readings 
  from 
  a 
  theodolite 
  and 
  a 
  range 
  finder, 
  but 
  later 
  on 
  

   these 
  instruments 
  were; 
  replaced 
  by 
  pairs 
  of 
  kinema-theodolites 
  

   disposed 
  at 
  the 
  ends 
  of 
  bases, 
  about 
  one-eighth 
  of 
  a 
  mile 
  long. 
  

   Several 
  pictures 
  were 
  thus 
  ground 
  per 
  second, 
  insuring 
  a 
  very 
  dense 
  

   record. 
  

  

  Not 
  only 
  true 
  soaring 
  flights 
  were 
  thus 
  surveyed, 
  also 
  special 
  

   straight 
  glides 
  were 
  taken 
  occasionally 
  on 
  particularly 
  calm 
  morn- 
  

   ings. 
  They 
  served 
  to 
  get 
  the 
  aerodynamic 
  characteristics 
  of 
  the 
  

   machines 
  themselves, 
  independent 
  of 
  any 
  soaring 
  action. 
  

  

  The 
  application 
  of 
  gliding 
  to 
  scientific 
  research 
  is 
  at 
  present 
  

   somewhat 
  limited 
  by 
  the 
  method 
  used 
  to 
  get 
  the 
  glider 
  started. 
  

   It 
  requires 
  the 
  windward 
  slope 
  from 
  a 
  mountain 
  crest, 
  whence 
  it 
  

   is 
  catapulted 
  into 
  the 
  wind 
  by 
  means 
  of 
  a 
  rubber 
  cord 
  pulled 
  by 
  a 
  

   crew 
  of 
  from 
  four 
  to 
  eight 
  people. 
  In 
  hilly 
  country 
  this 
  method 
  

   works 
  exceedingly 
  well; 
  but 
  one 
  had 
  often 
  wondered 
  how 
  much 
  

   more 
  gliding 
  would 
  be 
  popularized 
  if 
  some 
  method 
  of 
  take-off 
  

   could 
  be 
  devised 
  to 
  depend 
  less 
  on 
  topology. 
  

  

  I 
  once 
  tried 
  to 
  attach 
  the 
  glider 
  on 
  a 
  captive 
  balloon 
  of 
  the 
  

   Swiss 
  air 
  service, 
  and 
  to 
  take 
  off 
  from 
  there. 
  The 
  glider 
  was 
  

   suspended 
  some 
  100 
  feet 
  below 
  the 
  basket, 
  slightly 
  aft 
  of 
  its 
  own 
  

   center 
  of 
  gravity, 
  to 
  keep 
  its 
  nose 
  down. 
  Unfortunately, 
  this 
  

   entire 
  system 
  being 
  a 
  gigantic 
  double 
  pendulum, 
  immediately 
  

   started 
  to 
  perform 
  lateral 
  oscillations. 
  The 
  balloon 
  would 
  yaw 
  

   and 
  travel 
  to 
  one 
  side, 
  the 
  plane 
  would 
  prefer 
  the 
  opposite 
  side. 
  

   The 
  motion 
  was 
  not 
  fast 
  but 
  amplitudes 
  were 
  increasing. 
  I 
  was 
  

   unable 
  to 
  check 
  the 
  oscillations 
  by 
  use 
  of 
  my 
  controls. 
  Since 
  the 
  

   machine 
  would 
  also 
  always 
  bank 
  toward 
  the 
  wrong 
  side 
  I 
  was 
  

   forced 
  to 
  cut 
  loose 
  only 
  to 
  be 
  thrown 
  into 
  a 
  spin 
  to 
  recover 
  from 
  

   which 
  the 
  altitude 
  was 
  insufficient. 
  

  

  There 
  remains^ 
  the 
  possibility 
  of 
  fitting 
  the 
  glider 
  with 
  a 
  small 
  

   auxiliary 
  engine, 
  just 
  as 
  they 
  do 
  on 
  sailing 
  yachts. 
  Thus 
  the 
  glider 
  

   may 
  take 
  off 
  in 
  the 
  plains 
  and 
  fly 
  under 
  its 
  own 
  power 
  to 
  any 
  place, 
  

   where, 
  upon 
  meeting 
  soaring 
  flight 
  conditions, 
  the 
  engine 
  is 
  throttled 
  

   down 
  or 
  shut 
  off 
  and 
  the 
  real 
  sport 
  begins. 
  The 
  auxiliary 
  engine 
  

   would 
  also 
  help 
  out 
  a 
  glider 
  that 
  happens 
  to 
  drift 
  away 
  from 
  lifting 
  

   currents 
  or 
  runs 
  into 
  a 
  dead 
  calm. 
  As 
  a 
  matter 
  of 
  fact, 
  a 
  modern 
  

  

  ' 
  Quite 
  recently 
  Ilerren 
  Espciilaul), 
  Raab, 
  and 
  Katzenstcin 
  made 
  successful 
  experiments 
  

   by 
  having 
  a 
  glider 
  attached 
  to 
  and 
  towed 
  by 
  a 
  motor-powered 
  airplane. 
  Having 
  been 
  so 
  

   dragged 
  to 
  considerable 
  altitude, 
  they 
  cut 
  loose 
  and 
  glided 
  back 
  to 
  their 
  base. 
  They 
  also 
  

   towed 
  a 
  glider 
  from 
  one 
  town 
  to 
  another 
  via 
  air. 
  

  

  