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_Fig¡£¡¡16¡£¡¡Reversing¡¡Motion¡£_
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through¡¡a¡¡positive¡¡angle¡¡of¡¡incidence£»¡¡of¡¡the¡¡plane¡£
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THE¡¡SUGGESTED¡¡TYPE¡£In¡¡Fig¡£¡¡18¡¡the¡¡suggested
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the¡¡present¡¡type¡¡is¡¡launched¡£¡¡If£»¡¡by¡¡any¡¡error¡¡on
the¡¡part¡¡of¡¡the¡¡aviator£»¡¡he¡¡should¡¡fail¡¡to¡¡readjust
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after¡¡leaving¡¡the¡¡ground£»¡¡the¡¡machine¡¡would
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The¡¡machine¡¡may¡¡rise¡¡too¡¡rapidly£»¡¡or¡¡its
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angle£»¡¡but¡¡in¡¡either¡¡case£»¡¡neglect¡¡would¡¡not¡¡turn
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These¡¡suggestions¡¡are¡¡offered¡¡to¡¡the¡¡novice£»¡¡because
they¡¡go¡¡to¡¡the¡¡very¡¡foundation¡¡of¡¡a¡¡correct
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and¡¡while¡¡they¡¡are¡¡counter¡¡to¡¡the¡¡beliefs¡¡of
aviators£»¡¡as¡¡is¡¡shown¡¡by¡¡the¡¡persistency¡¡in¡¡adhering
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It¡¡must¡¡be¡¡obvious¡¡to¡¡the¡¡novice¡¡that¡¡the¡¡lower
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FORE¡¡AND¡¡AFT¡¡OSCILLATIONS¡£The¡¡answer¡¡is£»
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as¡¡it¡¡usually¡¡does¡¡instantaneously£»¡¡the¡¡weight£»¡¡being
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formed¡£
In¡¡Fig¡£¡¡19¡¡this¡¡action¡¡of¡¡the¡¡two¡¡forces¡¡is¡¡illustrated¡£¡¡The
plane¡¡at¡¡the¡¡speed¡¡of¡¡30¡¡miles¡¡is¡¡at
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being¡¡horizontal£»¡¡and¡¡the¡¡weight¡¡C¡¡suspended¡¡directly
below¡¡the¡¡supporting¡¡surfaces¡£
The¡¡moment¡¡the¡¡power¡¡ceases¡¡the¡¡weight¡¡continues
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end¡¡of¡¡the¡¡frame¡¡upwardly£»¡¡Fig¡£¡¡20£»¡¡and¡¡we¡¡now
have£»¡¡as¡¡in¡¡the¡¡second¡¡figure£»¡¡a¡¡new¡¡angle¡¡of¡¡incidence£»
which¡¡is¡¡30¡¡degrees£»¡¡instead¡¡of¡¡12¡£¡¡It¡¡will
be¡¡understood¡¡that¡¡in¡¡order¡¡to¡¡effect¡¡a¡¡change¡¡in
the¡¡position¡¡of¡¡the¡¡machine£»¡¡the¡¡forward¡¡end¡¡ascends£»
as¡¡shown¡¡by¡¡the¡¡dotted¡¡line¡¡A¡£
_Fig¡£¡¡20¡£¡¡Action¡¡when¡¡Propeller¡¡ceases¡¡to¡¡pull¡£_
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again¡¡swing¡¡back£»¡¡and¡¡again¡¡carry¡¡with¡¡it¡¡the
frame£»¡¡thus¡¡setting¡¡up¡¡an¡¡oscillation£»¡¡which¡¡is¡¡extremely
dangerous¡£
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in¡¡any¡¡degree£»¡¡aid¡¡in¡¡maintaining¡¡the¡¡frame¡¡on
an¡¡even¡¡keel¡£¡¡Being¡¡nearly¡¡horizontal¡¡while¡¡in
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APPLICATION¡¡OF¡¡THE¡¡NEW¡¡PRINCIPLE¡£Extending
the¡¡application¡¡of¡¡the¡¡suggested¡¡form£»¡¡let¡¡us¡¡see
wherein¡¡it¡¡will¡¡prevent¡¡this¡¡pendulous¡¡motion¡¡at
the¡¡moment¡¡the¡¡power¡¡ceases¡¡to¡¡exert¡¡a¡¡forwardly¡
propelling¡¡force¡£
_Fig¡£¡¡21¡£¡¡Synchronously¡¡moving¡¡Planes¡£_
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they¡¡are¡¡adjustable¡¡simultaneously¡¡at¡¡the¡¡same
angle£»¡¡and¡¡the¡¡weight¡¡D¡¡is¡¡placed¡¡below£»¡¡similar¡¡to
the¡¡other¡¡structure¡£
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of¡¡this¡¡type¡¡of¡¡structure£»¡¡the¡¡rear¡¡end¡¡of
the¡¡machine¡¡has¡¡a¡¡tendency¡¡to¡¡move¡¡upwardly£»
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weight¡¡seeks£»¡¡in¡¡this¡¡case¡¡to¡¡go¡¡on£»¡¡it¡¡acts¡¡on¡¡the
rear¡¡plane£»¡¡or¡¡tail£»¡¡and¡¡causes¡¡that¡¡end¡¡to¡¡raise£»
and¡¡thus¡¡by¡¡mutual¡¡action£»¡¡prevents¡¡any¡¡pendulous
swing¡£
LOW¡¡WEIGHT¡¡NOT¡¡NECESSARY¡¡WITH¡¡SYNCHRONOUSLY¡MOVING¡¡WINGS¡£
A¡¡little¡¡reflection¡¡will¡¡convince
any¡¡one¡¡that¡¡if¡¡the¡¡two¡¡wings¡¡move¡¡in¡¡harmony£»
the¡¡weight¡¡does¡¡not¡¡have¡¡to¡¡be¡¡placed¡¡low£»
and¡¡thus¡¡still¡¡further¡¡aid¡¡in¡¡making¡¡a¡¡compact
machine¡£¡¡By¡¡increasing¡¡the¡¡area¡¡of¡¡the¡¡tail£»¡¡and
making¡¡that¡¡a¡¡true¡¡supporting¡¡surface£»¡¡instead¡¡of
a¡¡mere¡¡idler£»¡¡the¡¡weight¡¡can¡¡be¡¡moved¡¡further
back£»¡¡the¡¡distance¡¡transversely¡¡across¡¡the¡¡planes
may¡¡be¡¡shortened£»¡¡and¡¡in¡¡that¡¡way¡¡still¡¡further
increase¡¡the¡¡lateral¡¡stability¡£
CHAPTER¡¡V
DIFFERENT¡¡MACHINE¡¡TYPES¡¡AND¡¡THEIR¡¡CHARACTERISTICS
THERE¡¡are¡¡three¡¡distinct¡¡types¡¡of¡¡heavier¡than¡
air¡¡machines£»¡¡which¡¡are¡¡widely¡¡separated¡¡in¡¡all
their¡¡characteristics£»¡¡so¡¡that¡¡there¡¡is¡¡scarcely¡¡a
single¡¡feature¡¡in¡¡common¡£
Two¡¡of¡¡them£»¡¡the¡¡aeroplane£»¡¡and¡¡the¡¡orthopter£»
have¡¡prototypes¡¡in¡¡nature£»¡¡and¡¡are¡¡distinguished
by¡¡their¡¡respective¡¡similarities¡¡to¡¡the¡¡soaring
birds£»¡¡and¡¡those¡¡with¡¡flapping¡¡wings¡£
The¡¡Helicopter£»¡¡on¡¡the¡¡other¡¡hand£»¡¡has¡¡no¡¡antecedent
type£»¡¡but¡¡is¡¡dependent¡¡for¡¡its¡¡raising
powers¡¡on¡¡the¡¡pull¡¡of¡¡a¡¡propeller£»¡¡or¡¡a¡¡plurality
of¡¡them£»¡¡constructed£»¡¡as¡¡will¡¡be¡¡pointed¡¡out¡¡hereinafter¡£
AEROPLANES¡£The¡¡only¡¡form¡¡which¡¡has¡¡met
with¡¡any¡¡success¡¡is¡¡the¡¡aeroplane£»¡¡which£»¡¡in
practice£»¡¡is¡¡made¡¡in¡¡two¡¡distinct¡¡forms£»¡¡one¡¡with
a¡¡single¡¡set¡¡of¡¡supporting¡¡planes£»¡¡in¡¡imitation¡¡of
birds£»¡¡and¡¡called¡¡a¡¡monoplane£»¡¡and¡¡the¡¡other¡¡having
two¡¡wings£»¡¡one¡¡above¡¡the¡¡other£»¡¡and¡¡called
the¡¡bi¡plane£»¡¡or¡¡two¡planes¡£
All¡¡machines¡¡now¡¡on¡¡the¡¡market¡¡which¡¡do¡¡not
depend¡¡on¡¡wing¡¡oscillations¡¡come¡¡under¡¡those
types¡£
THE¡¡MONOPLANE¡£The¡¡single¡¡plane¡¡type¡¡has
some¡¡strong¡¡claims¡¡for¡¡support¡£¡¡First¡¡of¡¡these
is¡¡the¡¡comparatively¡¡small¡¡head¡¡resistance£»¡¡due
to¡¡the¡¡entire¡¡absence¡¡of¡¡vertical¡¡sup
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