Lub ntsiab yog ib feem ntawm lub aircraft. aircraft ntaus ntawv

Invention ntawm lub dav hlau pub tsis tau tsuas yog nqa tawm ib qho kev laus npau suav ntawm noob neej - yuav tsum yeej xwb lub ntuj, tab sis kuj yuav ua tau ib lub ceev tshaj hom kev thauj. Tsis zoo li balloons thiab airships, dav hlau me ntsis nyob rau ntawm lub vagaries ntawm huab cua, yuav mus ntev mus nyob rau kev kub ceev. Cheebtsam ntawm lub aircraft muaj cov nram qab no cov yam ntxwv pab neeg: cov ib tis, fuselage, tus Tsov tus tw, tsaws iav, ib lub hwj chim cog tswj systems, ntau yam khoom.

hauv paus ntsiab lus ntawm cov lag luam

Aircraft - lub aircraft (LA) yog hnyav dua cov huab cua, txawm peem rau nrog ib lub hwj chim nroj tsuag. Nrog rau qhov no tseem ceeb heev ib feem ntawm lub aircraft los tsim tus tsim nyog thrust rau davhlau - kev khiav hauj lwm (tsav) dag zog yuam uas yog tsim nyob rau hauv hauv av los yog nyob rau hauv lub davhlau lub cav (kiv cua los yog cov dav hlau engine). Yog hais tias lub ntsia hlau nyob rau hauv pem hauv ntej ntawm lub engine, nws yog hu ua tus rub, thiab yog hais tias tus rov qab - thawb. Yog li, lub cav ua tus Translational tsab ntawv tsa suab ntawm cov aircraft txheeb ze mus rau lub surrounding nruab nrab (cua). Raws li, qhov cua tsiv txheeb ze rau lub tis, thiab hais tias tsim tau ib tug lifting quab yuam raws li ib tug tshwm sim ntawm lub Translational zog. Yog li ntawd, lub cav yuav kom nyob rau hauv cov huab cua xwb yog ib yam davhlau ceev.

Yuav ua li cas yog lub npe ntawm tus aircraft

Lub cev muaj cov nram qab no:

• Fuselage - yog lub cev lub ntsiab ntawm cov aircraft, txuas mus rau hauv ib tug tag nrho tis (tis), Plumage, fais tshuab, chassis thiab lwm yam. Lub fuselage accommodated cov neeg coob, cov neeg caij tsheb (civil aviation), cov khoom thiab payload. Nws tej zaum kuj yuav muab tso rau (tsis yeej ib txwm) roj, chassis, xyaw, thiab lwm yam .. d.
• Lub motors siv rau tsav lub zog ntawm tus aircraft.
• Koojtis - ua hauj lwm nto, tsim los nqa.
• Vertical tus Tsov tus tw tsim rau tuav, ntsuas thiab directional stability ntawm lub aircraft txog ib ntsug axis.
• Kab rov tav Tsov tus tw tsim rau tuav, ntsuas thiab directional stability ntawm lub aircraft hais txog ib tug kab rov tav axis.

Cov tis thiab fuselage

Lub ntsiab yog ib feem ntawm lub aircraft qauv - tis. Nws tsim lub tej yam kev mob rau qhov ua kom tiav ntawm lub ntsiab uas yuav tsum tau rau davhlau txuj - lub xub ntiag ntawm lub nqa. Cov tis yog txuas mus rau lub cev (fuselage), uas tej zaum yuav muaj ib qho kev zoo, tab sis raws li deb li sai tau nrog tsawg heev aerodynamic luag. Yuav kom qhov no kawg, nws muab ib tug yooj yim nco-streamlined zoo.

Lub pem hauv ntej ib feem ntawm lub aircraft yog siv rau kev tso kawm ntawm tus cockpit thiab radar tshuab. Thaum lub rear yog ib tug thiaj li hu ua tus Tsov tus tw. Nws ua hauj lwm pab kom muab cov kev tswj thaum lub sij hawm sib ntaus.

Tus tsim ntawm feathers

Xav txog qhov nruab nrab dav hlau, tus Tsov tus tw feem ntawm uas yog ua raws li cov classic tswvyim, ntse tshaj cov tub rog thiab pej xeem cov qauv. Nyob rau hauv cov ntaub ntawv no, lub kab rov tav Tsov tus tw yuav comprise ib taag ib feem - stabilizer (los ntawm Latin Stabilis, ruaj khov) thiab ib tug movable - elevator.

Lub stabilizer ua hauj lwm pab rau impart stability aircraft txog lub transverse axis. Yog hais tias lub aircraft qhov ntswg yuav poob, ces, raws li, aft fuselage, nrog rau plaub sawv li. Nyob rau hauv cov ntaub ntawv no, cov huab cua ceev nyob rau hauv lub qaum nto stabilizer nce. Generated siab stabilizer rov qab (ntsig txog, thiab fuselage) rau nws tus thawj txoj hauj lwm. Thaum tsa lub qhov ntswg ntawm lub fuselage ntawm huab cua khiav yuav kom lub siab nyob rau hauv qis saum npoo stabilizer, thiab nws yuav rov qab mus rau nws cov thawj txoj hauj lwm. Qhov no yog qhia tsis siv neeg (tsis muaj tsav kev pab) LA stability nyob rau hauv lub longitudinal dav hlau nrog rau kev hwm rau cov transverse axis.

Lub tsheb ntawm cov aircraft kuj muaj xws li ib tug ntsug tus Tsov tus tw. Ib yam li ntawd, kab rov tav, nws muaj ib tug taag ib feem - cov keel, thiab mobile - ko tw nyoob hoom. Keel muab stability dav hlau tsab ntawv tsa suab hais txog nws cov ntsug axis nyob rau hauv cov kab rov tav dav hlau. Lub hauv paus ntsiab lus ntawm cov lag luam yog zoo li qhov kev txiav txim ntawm lub stabilizer fin - tsis keel qhov ntswg deflected mus rau sab xis mus rau sab laug, lub siab nyob rau txoj cai-tes dav hlau nce thiab rov qab keel (thiab cov fuselage) mus rau lub yav dhau los txoj hauj lwm.

Yog li, nrog rau kev hwm rau ob axes ntawm davhlau stability yog ensured Plumage. Tab sis muaj lwm axis - longitudinal. Yuav kom muab automatic zog stability txoj kev uas axis (nyob rau hauv lub transverse dav hlau) glider tis console txheej txheem tsis horizontally tab sis nyob rau ntawm ib lub txheeb ze rau txhua tus lwm yam yog li ntawd lub xaus ntawm lub consoles deflected upward. Xws li ib tug kev kho tsa tsab ntawv «V».

tswj tshuab

Control chaw - ib qho tseem ceeb qhov chaw ntawm lub aircraft rau kev tswj cov aircraft. Cov no muaj xws ailerons, rudders thiab qhov siab. Control yog muab nrog hwm rau tib peb axes nyob rau hauv tib lub peb dav hlau.

Ua haujlwm of Elevator - ib tug movable rear ib feem ntawm lub stabilizer. Yog hais tias lub stabilizer muaj ob nkhaus, ntsig txog, muaj ob elevator uas thim upward los yog downward, ob qho tib si synchronously. Nrog nws, tus tsav yuav tau hloov lub aircraft davhlau altitude.

Ko tw nyoob hoom - ib tug movable rear ib feem ntawm lub keel. Thaum nws yog deflected mus rau ib sab los yog lwm nws tshwm sim aerodynamic dag zog yuam uas rotates lub dav hlau txog ib ntsug axis dua los ntawm qhov chaw ntawm loj nyob rau hauv kev coj rov qab los ntawm cov kev taw qhia ntawm txawv ntawm cov kauj log. Kev sib hloov tshwm sim raws li ntev raws li tus neeg tsav tsheb tsis rov qab lub kauj log rau hauv nruab nrab (uas tsis yog-deflected txoj hauj lwm), thiab LA yuav nqa tawm lub zog nyob rau hauv ib tug tshiab kev coj.

Ailerons (los ntawm Fabkis Aile, tis.) - qhov tseem ceeb ntawm cov aircraft, uas yog rooj noj qhov chaw tis panels. Lawv yog siv rau cov kev tswj ntawm lub aircraft txog lub longitudinal axis (nyob rau hauv lub transverse dav hlau). Txij li thaum lub ob tis panels, thiab cov ailerons thiab ob tug. Lawv ua hauj lwm synchronously, tab sis, nyob rau hauv sib piv rau lub elevators, tsis deflected mus rau ib sab, thiab sib txawv. Yog hais tias ib tug aileron yog deflected upwardly, lwm down. Nyob rau tis console qhov twg aileron deflected upward lifting dag zog yuam yog txo, thiab qhov chaw uas downward - yuav tsub kom. Thiab lub fuselage ntawm aircraft rotates nyob rau hauv cov kev taw qhia ntawm cov tsa aileron.

xyaw

Tag nrho cov aircraft yog nruab nrog ib tug propulsion system uas pub tsim ceev, thiab yog li ntawd muab ib tug lifting quab yuam. Xyaw tej zaum yuav muab tso nyob rau hauv sab nraum qab ntawm lub dav hlau (raug dav hlau aircraft), pem hauv ntej (small-engine tsheb) thiab cov tis (pej xeem aircraft, thauj, bomber).

Lawv muab faib ua:

• Reactive - turbojet, pulsating, dual-Circuit Court, txog-txaus.
• Ntsia Hlau - Piston (kiv cua uas tau tsav), turboprop.
• Missile - kua, khoom.

lwm yam systems

Ntawm cov hoob kawm, lwm qhov chaw ntawm lub aircraft yog tseem ceeb heev. Chassis cia aircraft hle thiab daim av nrog nruab airfields. Muaj amphibians, qhov twg tshwj xeeb floats yog siv es tsis txhob ntawm lub chassis - lawv tso cai rau koj mus hle thiab daim av nyob qhov chaw twg qhov twg muaj ib lub cev ntawm cov dej (hiav txwv, dej, pas dej). Paub cov qauv ntawm lub teeb aircraft nruab nrog skis, siv nyob rau hauv cheeb tsam uas muaj kev ruaj khov daus cover.

Niaj hnub nimno aircraft yog crammed nrog rau hauv cov khoom, kev sib txuas lus kiag li lawm thiab kis tau tus mob ntawm cov ntaub ntawv. Nyob rau hauv cov tub rog aviation siv sophisticated riam phom systems, lub hom phiaj tshaaj thiab teeb liab hluav.

kev faib

By lub sij hawm dav hlau raug muab faib ua ob pawg: pej xeem thiab cov tub rog. Lub ntsiab yog ib feem ntawm tus neeg nrog caij aircraft yog yus muaj los ntawm muaj nruab hav zoov coob uas xam nrog occupying ib tug loj ib feem ntawm lub fuselage. Ib tug txawv feature yog lub portholes nyob rau sab hauv lub cev.

Civil Aircraft yog muab faib mus rau hauv:

• Neeg nrog caij - lub zos airlines, lub ntsiab cov neeg nyob ze (ntau yam ntawm tsawg tshaj li 2000 km), cov phem (khwv yees li ntawm tsawg tshaj li 4000 km) ntev (deb ntawm tsawg tshaj li 9000 km) thiab intercontinental (ntau ntau tshaj 11 000 km).
• Cargo - Lub teeb (luj ntawm cargo mus txog 10 tonnes), medium (load hnyav txog li 40 tons) thiab hnyav (ceeb thawj ntawm lub load tshaj 40 tons).
• Tshwj xeeb lub hom phiaj - muaj kab mob, ua liaj ua teb, txawj ntse (ice reconnaissance, ryborazvedka), hluav taws kub-sib ntaus sib tua, rau aerial photography.
• Kev Kawm.

Tsis zoo li cov pej xeem ua qauv, ib feem ntawm ib tug tub rog aircraft muaj xis alarm nrog portholes. Lub ntsiab yog ib feem ntawm lub fuselage tuav riam phom systems, khoom siv rau cov kev tshawb kawm, kev sib txuas lus, motors thiab lwm yam units.

By lub sij hawm niaj hnub ua tub rog aircraft (xws li cov tub rog kev pab raws qib uas lawv ua) yuav tsum tau muab faib mus rau hauv lub nram qab no: fighters, nres dav hlau, bombers (missile), reconnaissance, ua tub rog thauj, tshwj xeeb thiab koom haum pab chaw.

aircraft ntaus ntawv

Lub apparatus ntawm aircraft nyob rau hauv lub aerodynamic Circuit Court, los ntawm uas lawv tsim. Aerodynamic daim duab tsiag ntawv los ntawm cov xov tooj ntawm yooj yim hais thiab kev kho ntawm kev coj tus kheej cov chaw. Yog hais tias lub qhov ntswg ntawm lub aircraft nyob rau hauv feem ntau ntawm cov uas zoo sib xws qauv, qhov chaw nyob thiab geometry ntawm lub tis thiab tus Tsov tus tw tshooj no ua tau nyias txawv nyias li.

Muaj cov nram qab no circuits LA ntaus ntawv:

• "Classical".
• "Ya tis".
• "Os".
• "Tailless".
• "Tandem".
• Convertible tswvyim.
• Ua ke tswvyim.

Aircraft los ntawm tus classical tswvyim

Xav txog qhov tseem ceeb ntawm cov aircraft thiab lawv cov functions. Classical (li qub) layout ntawm Cheebtsam thiab cov rooj sib txoos yog raug rau feem ntau pab kiag li lawm lub ntiaj teb no, txawm cov tub rog los yog pej xeem. Lub ntsiab caij - ib tug tis - kev khiav hauj lwm nyob rau hauv ib tug dawb huv undisturbed txaus uas ntws ntseeg nkaws tis thiab tsim ib tug tej yam lifting quab yuam.

Cov hneev nti ntawm lub khoom siv tes ua yog zog, uas thiaj li muaj qhov cheeb tsam yuav tsum tau (thiab chaw pib lub loj) ntawm lub ntsug stabilizer. Qhov no yog vim hais tias lub qhov ntswg ntawm lub fuselage ua destabilizing yawm sij hawm txog lub ntsug axis ntawm lub aircraft. Txo cov pem hauv ntej fuselage txhim kho lub xub ntiag rau pem hauv ntej hemisphere.

Qhov tsis zoo ntawm lub cev tswvyim yog raws li nram no:

• Txoj hauj lwm kab rov tav Tsov tus tw (HT) thiab ib tug sis tis perturbed kwj ho thiaj li nws ua hauj lwm zoo, necessitating siv ntawm feathers cheeb tsam loj (thiab chaw pib lub loj).
• ntsug tus Tsov tus tw (IN) los muab davhlau stability yuav tsum tau tsim ib tug tsis zoo nqa quab yuam, xws li downward. Qhov no thiaj li lub zuag qhia tag nrho efficiency ntawm lub aircraft: lub qhov ntau ntawm cov nqa, uas tsim ib tug tis, nws yog tsim nyog los noj cov nyhuv, uas yog tsim nyob rau hauv lub mus. nce tis cheeb tsam yuav tsum tau siv rau neutralize no phenomenon (thiab chaw pib lub loj).

aircraft ntaus ntawv rau ib tug "os"

Nrog cov qauv no, qhov tseem ceeb ntawm cov aircraft yog muab tso rau txawv tshaj nyob rau hauv "classical" qauv. Ua ntej ntawm tag nrho cov, cov kev hloov muaj kab-kab rov tav Tsov tus tw. Nws yog nyob rau hauv pem hauv ntej ntawm lub tis. Nyob rau hauv no cov tswvyim, ua nws thawj thawj lub dav hlau Bratya Rayt.

zoo:

• Vertical tus Tsov tus tw khiav hauv lub undisturbed flow, uas tsub kom nws ua hauj lwm zoo.
• Xav kom cov stability ntawm lub davhlau plaub tsim ib tug zoo nqa, piv txwv li nws yog ntxiv rau cov nqa ntawm lub tis. Qhov no tso cai rau kom txo nws cheeb tsam thiab, thiaj li, qhov hnyav.
• Ntuj "antispin" tiv thaiv: tau hloov cov tis ntawm supercritical cov ces kaum ntawm nres rau lub "os" cais tawm. Lub stabilizer yog teem li ntawd, hais tias nws tau txais ib tug ntau dua lub kaum sab xis ntawm nres tshaj li tus tis.
• Tsiv rov qab focal dav hlau nrog ua ceev thaum ib tug "os" no tshwm sim rau ib tug tsawg degree tshaj lub classical arrangement. Qhov no ua rau me kev hloov nyob rau hauv lub degree ntawm longitudinal zoo li qub stability ntawm lub aircraft, nyob rau hauv lem, simplifies cov kev tswj ntawm nws tus yam ntxwv.

Tsis zoo ntawm lub tswvyim "os":

• Los ntawm tshuam cov ndlwg ntawm feathering nws tshwm sim tsis tsuas yog nyob rau hauv lub tawm dav hlau me me thiab ces kaum ntawm nres, tab sis kuj nws cov "nrwg" vim lub yuav txo tau ntawm nws tag nrho lifting quab yuam. Qhov no yog tshwj xeeb tshaj yog txaus ntshai nyob rau hauv lub teb chaws vim hais tias ntawm qhov sib thooj ntawm takeoff thiab tsaws.
• Cov muaj nyob rau hauv lub rau pem hauv ntej fuselage tus Tsov tus tw impairs xyuas mechanisms ntawm lub sab hemisphere.
• Yuav kom txo tau qhov chaw ntawm lub hauv pem hauv ntej ntev ntawm mus rau pem hauv ntej fuselage yog tseem ceeb. Qhov no yuav tsub lub destabilizing yawm sij hawm, thiab, thiaj li, ua rau kom cov cheeb tsam thiab qhov hnyav ntawm lub tsev.

Aircraft ua rau ib tug "tailless"

Nyob rau hauv cov qauv ntawm cov hom yog tsis tseem ceeb, ib tug paub ib feem ntawm cov aircraft. Diam duab ntawm aircraft "beskhvostok" ( "Concord", "ua zaim muag", "Roob hluav taws") qhia tau hais tias lawv muaj tsis muaj kab rov tav Tsov tus tw. Lub ntsiab zoo ntawm no tswvyim yog:

• Txo cov frontal aerodynamic kuj, uas yog tshwj xeeb tshaj yog ib qho tseem ceeb rau aircraft thaum muaj kev kub ceev, xws li cruising. Qhov no thiaj li roj nqi.
• Loj tis torsional rigidity uas pab txoj kev aeroelastic yam ntxwv no tiav high yam ntxwv ntawm maneuverability.

disadvantages:

• Rau ntsuas nyob rau hauv ib co davhlau hom feem mechanization trailing ntug (flaps) thiab qhov tsim nyog los tswj tej chaw deflect upwards, uas thiaj li tag nrho cov nqa ntawm lub dav hlau.
• Thaum lawv tseem LA ntawm lwm yam uas lub kab rov tav thiab longitudinal axes (vim lub tsis tuaj kawm ntawv ntawm lub elevator), nws deteriorates cov yam ntxwv ntawm tuav. Qhov uas tsis muaj tshwj xeeb feathering ua tswj chaw nyob rau hauv lub rov qab ntug ntawm lub tis, mus nqa tawm (yog tias tsim nyog) xwb thiab ailerons thiab elevators. Cov kev tswj chaw yog hu ua elevons.
• Cov kev siv ntawm tus neeg kho tshuab txhais tau tias kom sib npaug rau aircraft impairs nws takeoff thiab tsaws yam ntxwv.

"Ya tis"

Nrog rau qhov no tswvyim, muaj zoo tsis muaj ib feem ntawm lub aircraft xws li cov fuselage. Tag nrho cov nqi uas yuav tsum tau kev tso kawm ntawm cov neeg coob, payload, cav, roj, thiab cov khoom yog nyob rau hauv nruab nrab ntawm lub tis. Qhov no tswvyim muaj cov nram qab zoo:

• Lub qis tshaj aerodynamic luag.
• Tus me tshaj loj ntawm cov qauv. Nyob rau hauv cov ntaub ntawv no, tag nrho cov loj ntog nyob rau tis.
• Txij li thaum lub longitudinal aircraft me me luaj li cas (vim tsis muaj kev fuselage), ib tug destabilizing caij nrog hwm rau nws ntsug axis yog negligible. Qhov no pub rau designers los yog txo tau qhov chaw ntawm NYOB RAU HAUV, los yog xaiv tawm ntawm nws (cov noog yuav paub ntsug tus Tsov tus tw yog tsis tuaj kawm ntawv).

Qhov tsis zoo yog cov complexity ntawm sustainability aircraft davhlau.

"Tandem"

Scheme "tandem", thaum ob tug tis txheej txheem ib tug tom qab lwm yam, tsis tshua muaj siv. Cov tshuaj no yog siv los mus nce lub cheeb tsam ntawm lub tis nyob rau tib lub qhov tseem ceeb ntawm nws cov amplitude thiab ntev ntawm lub fuselage. Qhov no thiaj li cov kev load nyob rau tis. Qhov tsis zoo ntawm no tswvyim yog lub loj aerodynamic luag, muaj lub caij ntawm inertia, tshwj xeeb tshaj yog nyob rau hauv relation mus rau lub transverse axis ntawm lub aircraft. Nyob rau hauv tas li ntawd, los ntawm kev ua cov kev ceev ntawm lub davhlau hloov lub yam ntxwv ntawm longitudinal tshuav nyiaj li cas hauv lub aircraft. Cov kauj nto xws dav hlau tej zaum yuav muab pov tseg ncaj qha rau ntawm cov tis, thiab nyob rau hauv Plumage.

neej coj tswvyim

Nyob rau hauv cov ntaub ntawv no, cov tivthaiv qhov chaw ntawm lub aircraft tej zaum yuav ua ke nrog rau ntau yam ntxwv schemes. Piv txwv li, kab rov tav Tsov tus tw thiab muab nyob rau hauv lub fore thiab aft fuselage. Lawv yog cov thiaj li hu ua ncaj tswj ntawm lifting quab yuam yuav tsum tau siv.

Nyob rau hauv cov ntaub ntawv no, qhov ntswg kab rov tav stabilizers ua ke nrog rau cov flaps muab ntxiv nqa. suab caij uas tshwm sim nyob rau hauv cov ntaub ntawv no yuav tsum tau qhia rau kom lub kaum sab xis ntawm nres (lub qhov ntswg dag). Rau lub sij hawm no Parry tailplane muaj tsim taw tes rau txo lub kaum sab xis ntawm nres (lub qhov ntswg). Ua li no, tus quab yuam nyob rau hauv tus Tsov tus tw seem yuav tsum tau raws kev coj kuj upwards. Hais tias yog, ib tug nqa increment ntawm lub rau pem hauv ntej mus rau hauv lub tis thiab tus Tsov tus tw mus (thiab chaw pib nyob rau tag nrho lub dav hlau) tsis muaj tig nws nyob rau hauv lub longitudinal dav hlau. Nyob rau hauv cov ntaub ntawv no, lub dav hlau tsuas nce tsis muaj evolution nrog hwm rau nws cov centre ntawm loj. Conversely, thaum xws aerodynamic configuration ntawm cov aircraft nws yuav nqa tawm lub evolution ntawm qhov chaw ntawm loj nyob rau hauv lub longitudinal dav hlau tsis muaj kev hloov lub trajectory ntawm nws cov davhlau.

Muaj peev xwm mus ua tau xws maneuvers ho txhim kho qhov kev kawm cov yam ntxwv ntawm Maneuvering aircraft. Tshwj xeeb tshaj yog nyob rau hauv ua ke nrog nrog ib tug ncaj qha sab quab yuam tswj system, uas lub aircraft yuav tsum tsis txhob tsuas muaj tus Tsov tus tw, thiab kuj yog ib tug longitudinal nyo hau feathering.

convertible tswvyim

Apparatus dav hlau lub tsev los ntawm cov convertible tswvyim, txawv los ntawm destabilizer nyob rau hauv lub rau pem hauv ntej fuselage. Destabilizers muaj nuj nqi yog txo mus rau ib tug tej yam twg, thiab txawm tag nrho tshem tawm ntawm rov qab zog ntawm tus aircraft aerodynamic kom pom tseeb rau ntawm supersonic davhlau regimes. Qhov no yuav tsub lub maneuverability ntawm lub aircraft (uas yog ib qho tseem ceeb rau ib tug fighter) thiab tsub kom qhov ntau thiab thiaj li noj roj (qhov no yog ib qho tseem ceeb rau ib tug supersonic neeg nrog caij aircraft).

Destabilizer tej zaum kuj yuav siv rau takeoff / tsaws ntsiab lus pab kom txawm peem lub dhia dej hom, uas yog tshwm sim los ntawm txawv ntawm lub tsaws mechanization (flaps, lub flaps) los yog lub fuselage qhov ntswg. Thaum subsonic davhlau regimes destabilizer lus dag nyob rau hauv nruab nrab ntawm lub fuselage los yog ntsia tau rau hauv lub cua ntsuas cua lag luam (dawb do oriented downstream).