basic aircraft structure.ppt

Yadav Khagendra K. M-tech(AME) [email protected]

Outline of Preentation  Aircraft !om"onent    

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Material ue in Airframe !ontruction E#am"le of Material ue in Airframe !ontruction $unction of Aircraft %tructure $uelage %tructure - &ru &y"e - Pratt &ru - 'arren &ru - Monocoue - %emi-Monocoue aic %tructure Mem*er &erm 'ing %tructure Em"ennage %tructure Po+er Plant - 'ing Pod Mount -$uelage Mount ,anding ear %tructure

Aircraft !om"onent A. Fuselage B. Wings C. Empenage or Tail D. Power Plant E. Landing Gear or Undercarriage

2ertical %ta*ili1er 0ori1ontal %ta*ili1er

'ing

/udder

/ight Aileron Elevator

Em"ennage

acelle

$uelage

,eft Aileron

,anding ear Pro"eller

'ing

Parts of an aircraft and teir

$uelage ! "ain #od$ of airplane ! Pilot % cargo compartments ! Generall$ constructed in two or more sections ! Carries accessories and oter e&uipments ! 'ncludes numerous access doors( inspection plates( landing weel wells( and oter openings

'3 ! Airfoils attaced to eac side of te fuselage ! "ain lifting surfaces ! )arious design si*e and sape ! "a$ #e attaced at te top( middle( or lower portion of te fuselage + ,ig+wing( mid+wing( and low+wing ! Te num#er of wings can also -ar$ + "onoplanes( #iplanes

Em"ennage ! now as tail section ! Consist of / )ertical 0ta#ili*er / 1udder / ,ori*ontal 0ta#ili*er / Ele-ators

Po+er Plant A unit or macine tat con-erts cemical energ$ contains in te fuel to trust force. Trust force is essential for mo-ing te airplane forward and producing lift force. Wit te piston engine( te propeller is used to con-ert tor&ue at engine saft to #e trust. Wit te 2et engine( te 2et engine output is te trust force.

,anding ear ! Located underneat of te fuselage wit soc3 strut ! Fi4ed 5 1etracta#le ! Pro-ides means of landing ta4iing ! Tri+ c$cle /Con-entional t$pe ! Floating gear for seaplane 5s3i+ e&uipped for ice surface landing etc..

Material ue in Airframe !ontruction Airframe "aterials Properties + ,ig 0trengt to Weigt ratio + Ligt weigt + Corrosion 1esistant + 0ould #e non flamma#le + ,ig &ualit$

E#am"le of Material ue in Airframe !ontruction • WOOD (Spruce) • STEEL & ITS ALLOYS (Strong ) • ALUMINIUM & ITS ALLOY (Commonly ue) • TITANIUM ALLOYS (!e"t #"rr$er) • MA%NESIUM ALLOYS ( t$me l$g'ter t'"n AL) • LASTICS & COMOSITE MATEIAL

$unction of Aircraft %tructure eneral  &he tructure of mot flight vehicle are thin +alled tructure (hell)

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/eit a""lied load (Aerodynamic load acting on the +ing tructure)  Provide the aerodynamic ha"e  Protect the content from the environment

4efinition Primary tructure5 A critical load+#earing structure on an aircraft. 'f tis structure is se-erel$ damaged( te aircraft cannot fl$. %econdary tructure5 0tructural elements mainl$ aerod$namics. Fairings( for were te wing meets te locations on te leading or wing.

to pro-ide enanced instance( are found #od$ or at -arious trailing edge of te

$uelage %tructure BA0'C 0T1UCTU1E T6PE0 &/6%% &YPE - P/A&& &/6%% - 'A//E &/6%% MOO!O76E %EM3-MOO!O76E

T1U00 T6PE "ost earl$ aircraft used tis tecni&ue wit wood and wire trusses and tis t$pe of structure is still in use in man$ ligtweigt aircraft using welded steel tu#e trusses. Te truss t$pe fuselage frame is assem#led wit mem#ers forming a rigid frame e.g. #eams( #ar( tu#e etc7 Primar$ mem#ers of te truss are 8 longerons. Tere are two t$pes of truss structure.

+ P1ATT T1U00

+ WA11E9 T1U00

P1ATT T1U00 ! Earl$ da$s ! Wooden or metal structure ! Great weigt ! Difficult to streamline ! Bo4 wit tu#ular longerons : -ertical mem#ers

Diagonal mem#ers of tu#ing or solid rods

WA11E9 T1U00 • Longeron * only D$"gon"l Mem+er • ,orce tr"n-er to e.ery ot'er tructure • C"p"+le to c"rry ten$on * compre$on • e/uce "mount o- 0e+ 0or1 • More p"ce 2 trengt' 2 r$g$/$ty • #etter tre"ml$ne

0tringers

Four longerons

Warren Truss 0tructure of an airplane

";9;C;
form of

tis

structure uses fi#erglass clot impregnated wit pol$ester or epo4$ resin( instead of pl$wood( as te s3in.

0E"'+";9;C;
0emi+monoco&ue 0tructure of an airplane

Te most common airframe construction is semi+monoco&ue

0emi+monoco&ue 0tructure of an airplane

Basic 0tructure "em#er Terms 3ert$c"l Mem+er • ,ormer • ,r"me • $ng • #ul1'e"/ Long$tu/$n"l Mem+er • Longeron • Str$nger

'ing %tructure "an$ ig+wing airplanes a-e e4ternal #races( or wing struts( wic transmit te fligt and landing loads troug te struts to te main fuselage structure. 0ince te wing struts are usuall$ attaced appro4imatel$ alfwa$ out on te wing( tis t$pe of wing structure is called semi-cantilever. A few ig+wing and most low+wing airplanes a-e a full cantilever wing designed to carr$ te loads witout e4ternal struts. Te principal structural parts of te wing are spars( ri#s( and stringers. Tese are reinforced #$ trusses( '+#eams( tu#ing( or oter de-ices( including te s3in. Te wing ri#s determine te sape and tic3ness of te wing =airfoil>.

'ing %tructure

'n most modern airplanes( te fuel tan3s eiter are an integral part of te wing structure( or consist of fle4i#le containers mounted inside of te wing. Attaced to te rear( or trailing( edges of te wings are two t$pes of control surfaces referred to as ailerons and flaps. Ailerons e4tend from a#out te midpoint of eac wing outward toward te tip and mo-e in opposite directions to create aerod$namic forces tat cause te airplane to roll. Flaps e4tend outward from te fuselage to near te midpoint of eac wing. Te flaps are normall$ flus wit te wing?s surface during cruising fligt. Wen e4tended( te flaps mo-e simultaneousl$ downward to increase te lifting force of te wing for ta3eoffs and landings.

Wing 0tructure of an airplane

Wing 0tructure of an airplane

Wings t$pes

swept#ac3 Wing =A@>

delta wing =concorde> )aria#le+sweep wing =Tornado F@> 0et

of wings( tat ma$ #e swept #ac3 and ten returned to its srcinal position during fligt.

Wings t$pes

Wings Positions

Em"ennage %tructure Te correct name for te tail section of an airplane is empennage. Te empennage includes te entire tail group( consisting of fi4ed surfaces suc as te -ertical sta#ili*er and te ori*ontal sta#ili*er. Te mo-a#le surfaces include te rudder( te ele-ator( and one or more trim ta#s. A second t$pe of empennage design does not re&uire an ele-ator. 'nstead( it incorporates a one+piece ori*ontal sta#ili*er tat pi-ots from a central inge point. Tis t$pe of design is called a stabilator( and is mo-ed using te control stic3( 2ust as $ou would te ele-ator.

Em"ennage %tructure Te rudder is attaced to te #ac3 of te -ertical sta#ili*er. During fligt( it is used to mo-e te airplane?s nose left and rigt. Te rudder is used in com#ination wit te ailerons for turns during fligt. Te ele-ator( wic is attaced to te #ac3 of te ori*ontal sta#ili*er( is used to mo-e te nose of te airplane up and down during fligt. Trim ta#s are small( mo-a#le portions of te trailing edge of te control surface. Tese mo-a#le trim ta#s( wic are controlled from te coc3pit( reduce control pressures. Trim ta#s ma$ #e installed on te ailerons( te rudder( and5or te ele-ator.

Empennage of an airplane

Empennage 0tructure of an airplane

0par 0tringers

1i#s

0tringers 0ta#ilator 03in 0par

Empennage 0tructure of an airplane

Aircraft tails T$pes

0tandard5Con-entional Twin tail

T+tail )+tail5 )+#utterfl$ tail

Beec Beeccraft Bonan*a

Aircraft tails T$pes

,anding ear %tructure Te landing gear is te principle support of te airplane wen par3ed( ta4iing( ta3ing off( or wen landing. Te most common t$pe of landing gear consists of weels( #ut airplanes can also #e e&uipped wit floats for water operations( or s3is for landing on snow. Te landing gear consists of tree weels  two main weels and a tird weel positioned eiter at te front or rear of te airplane. Landing gear emplo$ing a rearmounted weel is called con-entional landing gear.

,anding ear %tructure Airplanes wit con-entional landing gear are sometimes referred to as tail weel airplanes. Wen te tird weel is located on te nose( it is called nose weel( and te design is referred to as a tric$cle gear. A steera#le nose weel or tail weel permits te airplane to #e controlled trougout all operations wile on te ground.

Landing Gear Arrangement

Po+er Plant Te power plant usuall$ includes #ot te engine and te propeller. Te primar$ function of te engine is to pro-ide te power to turn te propeller. 't also generates electrical power( pro-ides a -acuum source for some fligt instruments( and in most single+engine airplanes( pro-ides a source of eat for te pilot and passengers. Te engine is co-ered #$ a cowling( or in te case of some airplanes( surrounded #$ a nacelle. Te purpose of te cowling or nacelle is to streamline te flow of air around te engine and to elp cool te engine #$ ducting air around te c$linders. Te propeller( mounted on te front of te engine( translates te rotating force of te engine into a forward acting force called trust tat elps mo-e te airplane troug te air.

• W$ng o/ Mount 4 Commonly ue on commerc$"l "$rpl"ne $nce -uel $ c"rry on 0$ng 4 Le no$e 4 CL m"5 $ not " goo/ " -uel"ge mount 4 Y"0$ng moment e6ect 4 %roun/ cle"r"nce l$m$t"t$on '$g'er ge"r trut

Fuselage "ount • • • • •

Cle"n 0$ng 2'$g' CL M"5 2 'orter t"1e o67 No groun/ cle"r"nce l$m$t"t$on Le y"0$ng e6ect We$g't pen"lty A-t Cg7 "n/ lo"/ /$tr$+ut$on C"+$n No$e "n/ 3$+r"t$on