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==Tecnica==
Il Boeing 777 è un [[monoplano]] bimotore con [[Ala (aeronautica)|ala]] bassa a [[freccia alare|freccia]], ampia [[fusoliera]] a sezione circolare, [[carrello d'atterraggio]] [[Carrello d'atterraggio#Carrello triciclo|triciclo anteriore]] e [[impennaggi]] in coda di tipo tradizionale. Nonostante l'aspetto esteriore convenzionale, però, il 777 ha introdotto un gran numero di tecnologie innovative, tra cui: un sistema completamente digitalizzato di controllo del volo mediato dal compuer ([[fly-by-wire]]);<ref name=fbw>{{cite news|last=North |first=David |title=Finding Common Ground in Envelope Protection Systems|work=Aviation Week & Space Technology |date=28 agosto 2008|pages=66}}</ref> un'[[avionica]] basata su software completamente configurabile; un ''[[glass cockpit]]'' con interfacce a [[Schermo a cristalli liquidi|cristalli liquidi]] [[Honeywell]];<ref>{{Cita|Birtles 1998|p. 57.}}</ref> e il primo impiego della [[fibra ottica]] nell'avionica di un aeroplano civile.<ref>{{Cita|Norris e Wagner 1996|p. 47.}}</ref> Per quanto riguarda le soluzioni tecniche, la Boeing si basò anche sul lavoro già svolto sul progetto del jet regionale Boeing 7J7, poi cancellato, il quale utilizzava tecnologie simili a quelle poi installate sul 777.<ref name=7j7>{{cite web|last=Sweetman |first=Bill |url=http://www.airspacemag.com/history-of-flight/prop-fan.html?c=y&page=5 |title=The Short, Happy Life of the Prop-fan |work=[http://www.airspacemag.com/ Air & Space]|date=1° settembre 2005|accessdate=9 luglio 2011}}</ref> Nel 2003 la Boeing cominciò a proporre l'opzione di un cockpit con ''electronic flight bag'' (borsa di volo elettronica), un sistema computerizzato di interfaccia e gestione delle informazioni progettato per ridurre la quantità di materiale cartaceo necessario per il volo (il quale normalmente trova posto nella vera e propria "borsa di volo" del pilota).<ref>{{cite web|last=Corliss|first=Bryan|url=http://www.forbes.com/2003/11/05/1105boeingpinnacor.html |title=New Boeing 777 Boasts Breakthrough Video System |work=[[Forbes]] |date=5 novembre 2003|accessdate=9 luglio 2011}}</ref>
=== Fly-by-wire ===
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===Struttura e sistemi===
Le ali del 777 sono basate su un [[Profilo alare|profilo]] [[Profilo alare#Profili supercritici|supercritico]] che, insieme a un
La struttura comprende una gran quantità di [[materiali compositi]], che costituiscono il 90% in peso dello "scheletro" dell'aeroplano.<ref>{{Cita|Norris e Wagner 1996|p. 35.}}</ref> La sezione principale della
[[File:Emirates Boeing 777-200LR First Class Suite.jpg|thumb|170px|Una suite di prima classe su un 777-200LR della [[Emirates Airlines|Emirates]].]]
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In riferimento alle diverse varianti, la Boeing e le compagnie aeree spesso contraggono il nome dell'aereo (777) fondendolo con il numero della versione (200 o 300) in una forma sintetica (772 o 773).<ref name=IATAcode>{{cite web |url=http://www.jal.co.jp/en/5971/readme/ships_info.html |title=About our operating aircraft |work=[http://www.jal.co.jp/en/ Japan Airlines] {{en}} |accessdate=10 luglio 2011}}</ref> Il sistema di designazione dei modelli d'aereo dell'Organizzazione Internazionale per l'Aviazione Civile ([[ICAO]]) prevede l'aggiunta di una lettera che identifica la casa produttrice (B772 o B773).<ref name=ICAOcode>{{cite web|url=http://www.icao.int/anb/ais/8643/ |title=ICAO Document 8643|work=[[Organizzazione Internazionale dell'Aviazione Civile]]|accessdate=10 luglio 2011}}</ref> Dopo il numero che specifica la lunghezza, le diverse designazioni possono o meno riportare un'altra lettera che si riferisce all'autonomia (il Boeing 777-300ER può essere designato come 773ER,<ref>{{cite news|url=http://www.smh.com.au/news/business/air-nz-must-ask-shareholders/2007/09/11/1189276720074.html |title=Air NZ must ask shareholders |work=[http://www.smh.com.au/ Sydney Morning Herald] |accessdate=10 luglio 2011 |last=John |first=Danny |date=12 settembre 2007}}</ref> 773B,<ref>{{cite news|url=http://www.atimes.com/atimes/China_Business/GL03Cb06.html |title=Cathay Pacific puts its trust in Boeing |work=[http://www.atimes.com/ Asia Times Online] |accessdate=10 luglio 2011 |date=3 dicembre 2005}}</ref> 77W<ref>{{cite web|url=http://www.aircanada.com/en/about/fleet/77W.html |title=Air Canada – 777-300ER (77W)|work=[http://www.aircanada.com/ Air Canada] |accessdate=10 luglio 2011}}</ref> o B77W<ref name=ICAOcode/>).
===777-200===
Il 777-200 è stata la versione iniziale per il mercato A. Con un'autonomia massima di 9 695 kilometri (5 235 miglia nautiche), la versione 200 era pensata essenzialmente per le compagnie che operano voli domestici all'interno degli [[USA]].<ref name=eden_112/> Il primo 200 fu consegnato alla [[United Airlines]] il [[15 maggio]] [[1995]],<ref name=Boe_777_back/> e al luglio 2011 nove<!-- JAL e International contate come una sola --> compagnie aeree avevano ricevuto in totale 88 esemplari.<ref name=777_O_D_summ>{{cite web |url=http://active.boeing.com/commercial/orders/displaystandardreport.cfm?cboCurrentModel=777&optReportType=AllModels&cboAllModel=777&ViewReportF=View+Report |title=777 Model Orders and Deliveries summary |work=[http://www.boeing.com/ Boeing] |date=Marzo 2011 |accessdate=10 luglio 2011}}</ref> Il modello Airbus che è diretto concorrente del 777-200 è l'[[Airbus A330|A330-300]].<ref>{{cite web|url=http://www.highbeam.com/doc/1G1-80189598.html|title=Aerospace Notebook: Conner's best bet – Let it ride on the 777s but airlines aren't ready to commit to 200LR model |work=[http://www.seattlepi.com/ Seattle Post-Intelligencer] |last=Wallace |first=James |date=19 novembre 2001 |accessdate=10 luglio 2011}}</ref>
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===777-
The 777-200ER ("ER" for Extended Range), the B-market version of the −200, was originally known as the 777-200IGW for its increased [[gross weight]].<ref>{{Harvnb|Eden|2008|pp=112–113}}</ref> The −200ER features additional fuel capacity and an increased [[maximum takeoff weight]] (MTOW) over the −200.<ref name="Boe_700-200-200ER_specs"/> Aimed at international airlines operating [[transatlantic flight|transatlantic]] routes,<ref name=Eden112/> the −200ER's maximum range is {{convert|7700|nmi|km}}.<ref name="Boe_700-200-200ER_specs"/> In addition to breaking the eastbound [[great circle]] "distance without landing" record, the −200ER also holds the record for the longest ETOPS-related emergency [[Diversion airport|flight diversion]] (177 minutes under one engine), on a United Airlines flight carrying 255 passengers on March 17, 2003, over the Pacific Ocean.<ref>{{cite web |url=http://www.aviationtoday.com/asw/categories/commercial/Still-Tops-for-ETOPS_2351.html |title=Still Tops for ETOPS |work=Air Safety Week |date=April 14, 2003 |accessdate=May 23, 2009}}</ref><ref>{{cite web|url=http://www.aviationtoday.com/asw/categories/bga/Divert-Details_2255.html |title=Divert Details |work=Air Safety Week |date=March 24, 2003 |accessdate=May 23, 2009}}</ref>
The first −200ER was delivered to [[British Airways]] on February 6, 1997.<ref name="Boe_777_back"/> As of March 2011, −200ER deliveries to 33 different customers numbered 415,<ref name=777_O_D_summ/> ranking the −200ER as the most widely produced variant of the twinjet to date.<ref name=eden113/> As of July 2010, 434 of the variant were in airline service.<ref name=FI10/><!-- Updates require a newer reference. --> The competing aircraft from Airbus is the [[A340-300]].<ref>{{cite web|last=Wall|first=Robert |url=http://www.aviationweek.com/aw/generic/story_generic.jsp?channel=awst&id=news/10315p03.xml |title=Boeing's Interest Focuses on 747 Advanced, Not 787-10 |work=Aviation Week & Space Technology |date=October 30, 2005 |accessdate=March 20, 2009}}</ref>
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===777-300===
[[File:Emirates.b777-300.a6-emv.arp.jpg|thumb|alt=Aircraft landing approach. Front quarter view of twin-engine jet in flight with flaps and landing gear extended.|An [[Emirates (airline)|Emirates]] 777-300 landing at [[London Heathrow Airport]]]]
The stretched 777-300 was designed as an A-market replacement for [[747-100]]s and [[747-200]]s.<ref name=norris151>{{Harvnb|Norris|Wagner|1999|pp=151–152}}</ref> Compared to the older 747s, the stretched variant has comparable passenger capacity and range, and is designed to burn one-third less fuel and have 40 percent lower maintenance costs.<ref name=norris151/> The −300 features a {{convert|33.3|ft|abbr=on}} fuselage stretch over the baseline −200, allowing seating for up to 550 passengers in a single class high-density configuration,<ref name=norris151/> an arrangement adopted for heavily trafficked Japanese routes.<ref>{{Harvnb|Birtles|1998|p=67}}</ref> Because of the aircraft's length, the −300 is equipped with a [[tailstrike|tailskid]] and ground maneuvering cameras to aid pilots during [[taxiing|taxi]].<ref>{{Harvnb|Norris|Wagner|1999|pp=152–156}}</ref> The maximum range is {{convert|6015|nmi|km}},<ref name="Boe_700-300_specs">{{cite web|url=http://www.boeing.com/commercial/777family/pf/pf_300product.html |title=777-300 Technical Characteristics |work=Boeing |accessdate=March 20, 2009}}</ref> allowing the −300 to operate [[trunk route]]s previously flown by older 747s.<ref name=norris151/>
The first −300 was delivered to [[Cathay Pacific]] on May 21, 1998.<ref name="Boe_777_back"/><ref name=norris157/> Eight different −300 customers have taken delivery of 60 aircraft,<ref name=777_O_D_summ/> and all were in airline service as of July 2010.<ref name=FI10/><!-- Updates require a newer reference.--> However, following the introduction of the longer-range −300ER in 2004, all operators have selected the ER version of the −300 model.<ref name=777_O_D_summ/> The −300 has no direct Airbus rival, but the A340-600 is offered in competition.<ref name=Flug773A>{{cite web |url= http://www.flug-revue.rotor.com/FRtypen/FR777300.htm |title= Datafile: Boeing 777–300 |work=Flug Revue |year=2006 |accessdate=March 20, 2009 |archiveurl= http://web.archive.org/web/20080130005719/http://www.flug-revue.rotor.com/FRtypen/FR777300.htm |archivedate= January 30, 2008}}</ref><ref name=Flug773>{{cite web |url=http://www.flug-revue.rotor.com/FRtypen/FR77730e.htm |title=Datafile: Boeing 777-300ER |work=Flug Revue |year=2006 |accessdate=March 20, 2009 |archiveurl=http://web.archive.org/web/20080129232450/http://www.flug-revue.rotor.com/FRtypen/FR77730e.htm |archivedate=January 29, 2008}}</ref>
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[[File:PIA B777-200LR AP-BGY.jpg|thumb|left|The first 777-200LR built, in service with [[Pakistan International Airlines]]|alt=Aircraft landing approach. Front quarter view of twin-engine jet in flight with flaps and landing gear extended.]]
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