aeroplanes and dirigibles of war-第7章

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when　conducting　experimental　flights；　absolutely　refused　to

descend；　producing　infinite　amusement　both　among　the　crowd　and

those　on　board。



The　development　of　the　Parseval　is　directly　attributable　to　the

influence　and　intimate　interest　of　the　Kaiser；　and　undoubtedly

this　represents　the　wisest　step　he　ever　made　in　the　realm　of

aeronautics。　　It　certainly　has　enabled　the　German　military

machine　to　become　possessed　of　a　significant　fleet　of　what　may　be

described　as　a　really　efficient　and　reliable　type　of　dirigible。　

The　exact　number　of　military　Parsevals　in　commission　is　unknown；

but　there　are　several　classes　thereof；　in　the　nature　of　aerial

cruisers　and　vedettes。



The　largest　and　most　powerful　class　are　those　known　as　the　B

type；　measuring　about　240　feet　in　length　by　40　feet　maximum

diameter；　of　223；000　cubic　feet　capacity；　and　fitted　with　two

motorsand　two　propellers。　　This　vessel　carries　about　10

passengers；　can　climb　to　a　maximum　height　of　approximately　8；500

feet；　and　is　capable　of　remaining　in　the　air　for　twenty　hours

upon　a　single　fuel　charge。　　While　this　is　the　largest　and　most

serviceable　type　of　Parseval　designed　for　military　duties；　there

is　another；　the　A　class；　200　feet　in　length　with　accommodation

for　six　passengers　in　addition　to　the　crew　of　three；　which　is

capable　of　attaining　a　maximum　altitude　of　6；700　feet；　and　has　an

endurance　capacity　of　15　hours。　　This　class　also　is　fitted　with

twin　propellers　and　motors。　　In　addition　there　are　the　C　and

E　classes；　carrying　from　four　to　eight　passengers；　while　the

vedettes　are　represented　by　the　D　and　F　classes；　which　have　a

maximum　altitude　of　2；000　feet　and　can　remain　aloft　for　only　five

hours　upon　a　single　fuel　charge。　　These　smaller　vessels；　however；

have　the　advantage　of　requiring　only　one　or　two　men　to　handle

them。　　The　present　military　Parseval　dirigible　is　made　in　one　of

these　five　standardised　classes；　experience　having　established

their　efficiency　for　the　specified　military　services　for　which

they　are　built。　　In　point　of　speed　they　compare　favourably　with

the　latest　types　of　Zeppelin；　the　speeds　of　the　larger　types

ranging　from　32　to　48　miles　per　hour　with　a　motor　effort　of　360

to　400　horse…power。



So　far　as　the　French　airships　of　war　are　concerned；　the　fleet　is

somewhat　heterogeneous；　although　the　non…rigid　type　prevails。　

The　French　aerial　navy　is　represented　by　the　Bayard…Clement；

Astra；　Zodiac；　and　the　Government…built　machines。　　Although　the

rigid　type　never　has　met　with　favour　in　France；　there　is　yet　a

solitary　example　of　this　system　of　constructionthe　Spiess；

which　is　460　feet　in　length　by　47　feet　in　diameter　and　has　a

displacement　of　20　tons。　　The　semi…rigid　craft　are　represented

by　the　Lebaudy　type；　the　largest　of　which　measures　293　feet　in

length　by　51　feet　in　diameter；　and　has　a　displacement　of　10　tons。



One　may　feel　disposed　to　wonder　why　the　French　should　be

apparently　backward　in　this　form　of　aerial　craft；　but　this　may　be

explained　by　the　fact　that　the　era　of　experiment　had　not　been

concluded　at　the　time　war　was　declared；　with　the　result　that　it

has　been　somewhat　difficult　to　determine　which　type　would　meet

the　military　requirements　of　the　country　to　the　best　advantage。　

Moreover；　the　French　military　authorities　evinced　a　certain

disposition　to　relegate　the　dirigible　to　a　minor　position；

convinced　that　it　had　been　superseded　by　the　heavierthan…air

machine。　　Taken　on　the　whole；　the　French　airship　fleet　is

inferior　to　the　German　in　point　of　speed；　if　not　numerically；　but

this　deficiency　is　more　than　counterbalanced　by　the　skill　and

ability　of　the　men　manning　their　craft；　who　certainly　are

superior　to　their　contemporaries　in　Germany；　combined　with　the

proved　character　of　such　craft　as　are　in　service。



The　same　criticism　may　be　said　to　apply　to　Great　Britain。　　That

country　was　backward　in　matters　pertaining　to　the　airship；

because　its　experiments　were　carried　out　spasmodically　while

dependence　was　reposed　somewhat　too　much　upon　foreign　effort。　

The　British　airships　are　small　and　of　low　speed　comparatively

speaking。　　Here　again　it　was　the　advance　of　the　aeroplane　which

was　responsible　for　the　manifestation　of　a　somewhat　indifferent

if　not　lethargic　feeling　towards　the　airship。　　Undoubtedly　the

experiments　carried　out　in　Great　Britain　were　somewhat

disappointing。　　The　one　and　only　attempt　to　out…Zeppelin　the

Zeppelin　resulted　in　disaster　to　the　craft　before　she　took　to　the

air；　while　the　smaller　craft　carried　out　upon　far　less　ambitious

lines　were　not　inspiritingly　successful。　　Latterly　the　non…rigid

system　has　been　embraced　exclusively；　the　craft　being　virtually

mechanically　driven　balloons。　　They　have　proved　efficient　and

reliable　so　far　as　they　go；　but　it　is　the　personal　element　in

this　instance　also　which　has　contributed　so　materially　to　any

successes　achieved　with　them。



But　although　Great　Britain　and　France　apparently　lagged　behind

the　Germans；　appreciable　enterprise　was　manifested　in　another

direction。　　The　airship　was　not　absolutely　abandoned：　vigilance

was　maintained　for　a　superior　type　of　craft。　　It　was　an　instance

of　weighing　the　advantages　against　the　disadvantages　of　the

existing　types　and　then　evolving　for　a　design　which　should

possess　the　former　without　any　of　the　latter。　　This　end　appears

to　be　achieved　with　the　Astra　type　of　dirigible；　the　story　of　the

development　of　which　offers　an　interesting　chapter　in　the　annals

of　aeronautics。



In　all　lighter…than…air　machines　the　resistance　to　the　air

offered　by　the　suspension　ropes　is　considerable；　and　the

reduction　of　this　resistance　has　proved　one　of　the　most

perplexing　problems　in　the　evolution　of　the　dirigible。　　The　air

is　broken　up　in　such　a　manner　by　the　ropes　that　it　is　converted

into　a　brake　or　drag　with　the　inevitable　result　that　the　speed

undergoes　a　severe　diminution。　　A　full…rigged　airship　such　as　the

Parseval；　for　instance；　may　present　a　picturesque　appearance；　but

it　is　severely　unscientific；　inasmuch　as　if　it　were　possible　to

eliminateor　to　reduce　the　air…resistance　offered　by　the　ropes；

the　speed　efficiency　might　be　raised　by　some　sixty　per　cent　and

that　without　any　augmentation　of　the　propelling　effort。　　As　a

matter　of　fact　Zeppelin　solved　this　vexatious　problem

unconsciously。　　In　his　monster　craft　the　resistance　to　the　air　is

reduced　to　a　remarkable　degree；　which　explains　why　these　vessels；

despite　all　their　other　defects　are　able　to　show　such　a　turn　of

speed。



It　was　this　feature　of　the　Zeppelin　which　induced　Great　Britain

to　build　the　May…fly　and　which　likewise　induced　the　French

Government　to　stimulate　dirigible　design　and　construction　among

native　manufacturers；　at　the　same　time；　however；　insisting　that

such　craft　should　be　equal　at　least　in　speed　to　the　Zeppelins。　

The　response　to　this　invitation　was　the　Spiess；　which　with　its

speed　of　45　miles　per　hour　ranked；　until　1914；　as　one　of　the

fastest　dirigibles　in　the　French　service。



In　the　meantime　a　Spanish　engineer；　Senor　Torres；　had　been

quietly　working　out　a　new　idea。　　He　realised　the　shortcomings　of

the　prevailing　types　of　airships　some　eleven　years　ago；　and

unostentatiously　and　painstakingly　set　out　to　eliminate　them　by

the　perfection　of　a　new　type　of　craft。　　He　perfected　his　idea；

which　was　certainly　novel；　and　then　sought　the　assistance　of　the

Spanish　Government。　　But　his　fatherland　was　not　adapted　to　the

prosecution　of　the　project。　　He　strove　to　induce　the　authorities

to　permit　even　a　small　vessel　to　be　built；　but　in　vain。　　He　then

approached　the　French　Astra　Company。　　His　ambition　was　to　build　a

vessel　as　large　as　the　current　Zeppelin；　merely　to　emphasise　the

value　of　his　improvement　upon　a　sufficiently　large　scale；　and　to

enable　comparative　data　concerning　the　two　designs　to　be

obtained。　　But　the　bogey　of　expense　at　first　proved　insuperable。　

However；　the　French　company；　decided　to　give　the　invention　a

trial；　and　to　this　end　a　small　〃vedette〃　of　about　53；000　cubic

feet　displacement　was　built。



Although　an　unpretentious　little　vessel；　it　certainly　served　to

emphasise　the　importance　of　the　Torres　idea。　　It　was　pitted

against　the　〃Colonel　Renard；〃　the　finest　ship　at　that　time　in　the

French　aerial　service；　which　had　proved　the　fastest　airship　in

commission；　and　which　also　was　a　product　of　the　Astra　Company。　

But　this　fine　craft　was　completely　outclassed　by　the　puny

Astra…Torres。



The　builders　and　the　inventor　were　now　additionally　anxious

to　illustrate　more　emphatically　the　features　of　this　design　and

to　build　a　far　larger　vessel。　　The　opportunity　was　offered　by　the

British　Government；　which　had　been　following　the　experiments　with

the　small　Astra…Torres　in　France。　　An　order　was　given　for　a

vessel　of　282；500　cubic　feet　displacement；　in　this　instance　it

was　ranged　against　another　formidable　rivalthe　Parseval。　　But

the　latter　also　failed　to　hold　its　own　against　the　Spanish

invention；　inasmuch　as　the　Astra…Torres　built　for　the　British

authorities　exceeded　a　speed　of　50　miles　per　hour　in　the　official

tests。　　This　vessel　is　still　doing　valuable　duty；　being　attached

to　the　British　air…service　in　France。



The　achievements　of　the　British　vessel　were　not　lost　upon　the

French　Government；　which　forthwith　placed　an　order　for　a　huge

vessel　of　812；200　cubic　feet　capacity；　equipped　with　motors

developing　1；000　horse…power；　which　it　was　confidently　expected

would　enable　a　speed　of　60　miles　per　hour　to　be　attained。　　Thus

France　would　be　able　to　meet　the　Germans　upon　fairly　level　terms；

inasmuch　as　the　speed　of　the　latest　Zeppelins　does　not　exceed　60

miles　per　hour。　　So　confident　were　the　authorities　that　a　second

order　for　an　even　larger　vessel　was　placed　before　the　first　large

craft　was　completed。



This　latter　vessel　is　larger　than　any　Zeppelin　yet　built；　seeing

that　it　displaces　38　tons；　and　is　fitted　with　motors　developing

1；000　horse…power。　　It　has　recently　been　completed；　and　although

the　results　of　the　trials；　as　well　as　the　dimensions　of　the　craft

have　not　been　published；　it　is　well　known　that　the　speed　has

exceeded　60　miles　per　hour；　so　that　France　now　possesses　the

speediest　dirigible　in　the　world。



The　Torres　invention　has　been　described　as　wonderful；

scientifically　perfect　and　extremely　simple。　　The　vessel　belongs

to　the　non…rigid　class；　but　the　whole　of　the　suspension　system　is

placed　within　the　gas…bag；　so　that　the　air…resistance　offered　by

ropes　is　virtually　eliminated　in　its　entirety；　for　the　simple

reason　that　practically　no　ropes　are　placed　outside　the　envelope。　

The　general　principle　of　design　may　be　gathered　from　the

accompanying　diagram。　　It　is　as　if　three　sausage…shaped　balloons

were　disposed　pyramidallytwo　lying　side　by　side　with　one

super…imposed；　with　the　bags　connected　at　the　points　where　the

circular　sections　come　into　contact。　　Thus　the　external

appearance　of　the　env