Choix de moteurs et exclusivités
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lequebecois
Inscrit le 11/02/2007 |
# 26 mars 2009 21:51 | |
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Des nouvelles de Pratt & Whitney : - Le premier PW4000 au standard Advantage70 a fait son premier vol sur un A330-200 destiné à Air Comet. http://www.pw.utc.com/vgn-ext-templatin ... mt=default - El Al conclut une ententte de 1 an avec le constructeur pour nettoyer ses moteur de 747 et 777. Cela permattra au transporteur d'économiser 1.2% en carburant, diminuer de 15 degré Celsius les gaz d'échappement et diminuer les émissions ainsi qu'augmenter le "time-on-wing". http://www.pw.utc.com/vgn-ext-templatin ... mt=default _________________ Le bonheur est une pause entre deux emmerdes ! Adepte de la discutaille du coin du comptoir du café de la gare |
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Beochien
Inscrit le 13/02/2007 |
# 30 mars 2009 13:17 | |
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Un article de fond, avec les approches techno, assez bien divulguées pour le GTF de P&W ckez ATW , de février, pas vu ici je crois ... - Intéressant : La techno du Fan, le démo était en titane plein, les autres options évaluées, Titane creux, façon RR, composite etc ... noter aussi, que la plus faible vitesse du fan est un avantage pour le poids, précautions anti "Bird - Strike" et aubes cassées peuvent être revues à la baisse ... - Comparatifs "Poids" intéressants ! - Les écos dans les clous de ce qui s'annonçait ! - Des précisions sur les divers "Coeurs" limités à 30 000 lbs ! Peut être un peu court à mon avis perso surtout pour la next-gen 737-320 qui, même s'ils s'allégent de qq tonnes, pourraient aussi grandir ... pas vraiment un bon calcul à mon avis ... et une impasse pour d'eventuelles re-motorisations ... Leurs choix à P&W ...cet abandon du dévlpt vers le haut à court-moyen terme ... Ou tout n'est pas dit, peut être ...spéculons ... Entre P&W et Airbus, beaucoup trop de silence radio ... ça peut aller dans les 2 sens ... - Aucun intérêt immédiat ! - Ou un développement non annoncé pour l'instant pour laisser Boeing dans le doute qq mois de plus, qui sait! - Ce que l'on sait est qu'Airbus et AF pensent, voire exigent les 15%, P&W offre 12%, il ne manque que 2-3 points et qq 3000 lbs pour couvrir la gamme jusqu'au A321 ! Impossible sous 3-4 ans ?? Je pense perso le contraire ! A Suivre -------------- ATW, Extrait --------------- http://www.atwonline.com/magazine/artic ... cleID=2220 Big Gains The company has set aggressive performance targets for the baseline GTF, including a 12% improvement in fuel burn (and equivalent cut in carbon dioxide emissions) and a 40% reduction in maintenance costs compared to the V2500 and CFM56-5B/7B engines in service today, with a 55% reduction in NOx emissions relative to CAEP6 and a cumulative 20 dB decrease in noise levels from Stage 4. The dramatic cut in NOx emissions comes from the rich-quench-lean TALON (Technology for Advanced Low NOx) combustor. The newest version, TALON X, is being developed in partnership with NASA for the GTF. Central to most of the other improvements is the gear system that enables the fan to operate independently of and at a slower, more optimum speed than the low-pressure compressor and turbine. "The fan will turn at about one-third the speed of the LPT, whereas in a conventional engine the fan turns at the same speed," Saia notes. In the case of the GTF, the LPT will operate at 8,500-9,000 RPM with the fan running at approximately 2,800-3,000 RPM. This results in substantially greater efficiency and less noise at the front, while the LPC and LPT can be run at much higher speeds, likewise maximizing their efficiency. Because it is running slower, the fan and the bypass ratio can be significantly larger and the characteristic flow disruption at the tip of the blade is minimized. "The slower you can make the blade, the less loss of the actual airfoil," he explains. Noise reduction is "a key element." Saia suggests the quietness of the GTF could result in noteworthy operational savings arising from the ability to use preferred runways and more optimum flightpaths. On a 500-nm. mission, 3 min. saved avoiding a noise abatement track results in a 3.5% fuel burn saving, he says, while the ability to use a more preferential runway can reduce fuel burn 0.4% for every minute saved. Historically, the drawbacks to using a gearbox in a jet engine have been reliability and added weight. Pratt says neither is an issue today. Saia claims that the company's gear system adds less than 1% in weight while permitting the powerplant to be 10% lighter than today's engines. The availability of lighter materials certainly plays a role, but the savings is largely because the core can be run at its optimum speed, resulting in far more efficiency. This means fewer stages and airfoils, driving down maintenance costs as well. Today's narrowbody engines have around 3,500 LPT and LPC airfoils while the GTF will have 2,000. Lowering the fan speed also saves weight. Saia explains: "When you slow the blade down, the impact damage of a bird or of a fan blade release is a lot less because you don't have all that velocity impact on the airfoil or on the containment case . . . We can get a lot of weight out of the fan structure just because of the lower velocity of the blade." As for reliability, officials note that Pratt has spent more than a decade developing geared technology. "We flew our geared PropFan in 1988-89 [in cooperation with Allison] and we did a PW2000 demonstrator in 1992-93 and then we did a Pratt Canada ATFI [Advanced Turbofan Engine] in 2001-02," Saia recalls. The GTF demonstrator project got underway in 2004, which means the engine-maker will have nine years of experience before it enters service. Fewer Fan Blades The engine will have 18 wide-chord swept blades compared to 22 on Pratt's PW4084 for the 777 and 38 on its earlier 747-400 engine. The blades in the demonstrator are solid titanium but the company is looking at three options for production engines: Hollow titanium, a lighter hollow metallic material and a composite similar to that used in large propellers. It is working with sister company Hamilton Sundstrand on the last. "They've been doing a lot of research and development on very large wide-chord [composite] propellers. They are responsible for the propeller on the A400M [military transport]. They've also been doing work with high-speed architecture," Saia points out. Pratt's plan is to use the lightweight metallic material for the MRJ and CSeries applications. He speculates that "it might be that we would use a lightweight metal in some thrust classes and the composite lay-up for a different thrust class," while cautioning that the company is still very much in the development stage. _________________ JPRS |
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Beochien
Inscrit le 13/02/2007 |
# 2 avril 2009 02:18 | |
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La FAA n'est plus ce qu'elle était ! Comique ! Sévére rebuffade contre GE, qui suggérait de changer (Suaviser) certaines lignes d'un AD concernant : Des joint du CF34 qui ont causé un non réallumage des 2 moteurs, aprés un flame out causé par 2 pilotes de CRJ200, qui s'amusaient à amener leur avion au plus haut (Sans pax) jusqu'au point de décrochage à 41 000 pieds ... Excès de friction des joints du moteur, et ce n'est pas reparti ! Crash au bout ! Changement mineur sur les CF34, mais trés symbolique ! La FAA ne semble plus se laisser dicter les régles du jeux par GE ! Les temps ont changé ! Un retour en arrière sur les conditions de la certification, épreuve des contained failures du Fan, du Genx* ... * Chez tout les motoristes, il fallait retenir une pale complète qui se détache ... et GE avec sa technologie "magique" a "convaincu" la FAA qu'une 1/2 aube de fan suffirait ... on se rappelle ! On n'en est pas là, mais attention au premier pépin concernant le Fan du Genx, ça pourrait chauffer après, si la ligne dure est maintenue ! ------------------------ De Flightglobal, L'article -------------------------- http://www.flightglobal.com/articles/20 ... nacle.html FAA mandates GE CF34 changes stemming from Pinnacle crash By John Croft The US Federal Aviation Administration (FAA) has concluded that "excessive" friction between the static and rotating portions of a certain seal inside the General Electric CF34 turbofan engine under certain high-power, high-altitude conditions is unsafe and must be corrected. A final rule to be published tomorrow calls on US operators of some 2,450 CF34 engines to replace the original 4-step air balance piston seals with 8-step seals at the next life-limited parts replacement interval, a relatively inexpensive modification expected to take five hours per engine. The issue gained prominence in the investigation of the Pinnacle Airlines Bombardier CRJ200 crash in 2004. Both pilots were killed during the repositioning flight after purposefully stalling the aircraft at 41,000ft and experiencing a dual flameout that resulted in core lock of both engines. The crew initially misreported the situation to air traffic controllers, and ultimately failed to restart the engines. The aircraft crash-landed short of the airport in a Missouri neighbourhood. According the FAA, GE had found during the post-crash investigation "that under certain high-power, high-altitude engine shutdown events, interference between the rotating and stationary portions of the CF34's 4-step air balance piston seal can develop". After the airworthiness directive was first proposed in July 2008, the engine manufacturer requested that the FAA remove references to "excessive friction" in the seal. Instead GE said it would be "more accurate" to say that by reducing the friction, the modification would enhance the ability to restart an engine after flameout. GE also asked that the FAA change the AD's incident description stating "both engines experienced high-altitude flameouts" to reflect the fact that the engines flamed out after the pilots performed a high-altitude stall and upset. The FAA rebuffed GE on both requests however, saying that GE's proposed wording regarding "reduced friction" would suggest the seal change out "may not be adequate to address the inability to restart (the engines) due to the friction". Commenting on the AD GE says it respectfully disagrees that there is an unsafe condition in the engine, noting the rulemaking is a response to "an engine condition that is extremely rare". _________________ JPRS |
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Beochien
Inscrit le 13/02/2007 |
# 4 avril 2009 10:31 | |
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RR signe un accord de 350 millions de $ pour le "Total care" des BR 715 des B717 récemment loués par Boeing Leasing à Mexicana, du moins pour sa filiale low cost ....Mexicanaclick ! Des chiffres intéressants, voire surprenants .... 7 milions de $ par moteur ... sur "Presque 20 ans" ... bien plus cher qu'un moteur neuf ! Etonnant que Mexicana signe pour une si longue période, pour des avions usagés, qui auront bien du mal à rester aussi longtemps en service ... il doit y avoir un paquet de clauses de sortie, bien sûr ! Noter quand même que Mexicana s'intéresse aux C -Séries pour 2014 ou aprés ! http://lapresseaffaires.cyberpresse.ca/ ... series.php RR annonce aussi que 55% de ses moteurs bénéficient de contrats "Total care" sûrement un succés, et une rente des plus confortables probablement ! ------------- Dans toute les coms ce matin ! L'article de RR -------------------------- http://www.rolls-royce.com/civil/news/2 ... ntract.jsp Mexicanaclick awards Rolls-Royce $350 million contract Friday, 3 April 2009 Rolls-Royce has signed a long-term engine service agreement worth more than $350 million with Mexicana Group for the fleet of aircraft operated by its low-cost subsidiary, MexicanaClick. The TotalCare® agreement covers 25 newly leased Boeing 717-200s, powered by Rolls-Royce BR715 engines. Today, more than 55 per cent of Rolls-Royce’s modern jet engine fleet is covered by TotalCare or CorporateCare® service agreements. Ricardo Baston, Executive Vice President, Corporate Planning and Fleet Transactions, Mexicana Airlines said: “Mexicana prides itself on reliability, innovation and technology. We have relied on high-performance Rolls-Royce engines for nearly 20 years. Selection of the BR715 for MexicanaClick will bring class leading payload and reliable performance, supported by Rolls-Royce’s world class TotalCare program.” Lewis Prebble, Rolls-Royce Vice President of Customer Business said: “We are delighted to begin the next chapter in this long-standing relationship. TotalCare will deliver tailored and comprehensive engine services for Mexicana, underpinned by deep engine expertise that only we can provide.” The Boeing 717-200, for which Rolls-Royce provides the sole power plant available, is the quietest, most efficient airframe and engine combination in its class. The BR715 offers operators benefits such as: noise levels far below current [Chapter 4 noise rules] regulations; emissions well below current ICAO regulations; and up to 25 per cent improved fuel burn relative to previous generation power plants. Specific fuel consumption (SFC) levels are the lowest in its thrust class, enabling outstanding aircraft range. _________________ JPRS |
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lequebecois
Inscrit le 11/02/2007 |
# 8 avril 2009 16:10 | |
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Saudi Arabian Airlines choisi le Trent 772 pour les 8 (+ 4 options) A330 qui seront livré à partir de 2010. http://www.rolls-royce.com/civil/news/2 ... rlines.jsp (Dernière édition le 8 avril 2009 16:10) _________________ Le bonheur est une pause entre deux emmerdes ! Adepte de la discutaille du coin du comptoir du café de la gare |
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Beochien
Inscrit le 13/02/2007 |
# 15 avril 2009 23:17 | |
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Un article de Flightglobal, bien intéressant concernant les "Ultra-High By Pass " Vus de l'EU ! MTU a renoncé ! Comme quoi le Tx de 12 serait optimum pour làaSFC bravo pour P&W, 14 max pour le bruit, mais pas pour la conso , pour les Turbo-Fan, bien sûr ! RR et Snecma ... ça ne leur convient pas trop ... on verra, ils on leur solutions, pas forcément dans ce "Cadre" pour les résultats on attends 2015-16 à suivre ! ! ----------------------- L'article Flight Global ----------------------- http://www.flightglobal.com/articles/20 ... rgets.html Ultra-high-bypass engines to enable green targets By Rob Coppinger Europe's environmental engine targets for 2020 can be met using engines with a bypass ratio of 14, according to an analysis tool developed for the European Union's Environmentally Friendly Aero-engine (Vital) project. Europe's targets, set by the Advisory Council for Aeronautical Research in Europe (ACARE), are reductions of 50% in perceived noise, 80% in nitrogen oxides output and 50% in carbon dioxide emissions. The ratio is the difference between the fan drawn air going into and around the engine core. Today's engines' bypass ratios are less than 10. The bypass ratio of 14 was calculated by the Techno-economic Environmental Risk Assessment (TERA) 2020 tool. This uses a variety of data including plant costs to determine the optimal engine type. For Vital it will help the project determine which of the three engine architectures under study can achieve the ACARE targets. Snecma's contra-rotating concept, Rolls-Royce's direct drive design and MTU Aero Engines' geared system were the three turbofan architectures studied, although MTU does not intend to develop such an engine. Cranfield University TERA 2020 researcher Stephen Ogaji says that TERA shows a bypass ratio of 14 across the three architectures under study tended to give the results sought by ACARE. R-R and Snecma emphasise that TERA's results to date have been based on existing public domain data and not confidential commercial engine and airline operation data. The TERA 2020 tool also showed that a bypass ratio of 12 was optimal for fuel burn, not 14, which only improved noise. Beyond a ratio of 12, drag and wing integration issues were found to reduce specific fuel consumption. TERA 2020 will be used by Vital's participants and is being deployed for the EU validation of radical engine architecture systems, or Dream project, and the ongoing sixth framework New Aero Engine Core Concepts study. _________________ JPRS |
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Beochien
Inscrit le 13/02/2007 |
# 23 avril 2009 12:12 | |
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Un article du & avril, concernant la gamme Purepower de P&W ! ou l'on peut voir d'intéressantes informations, concernant le Scaling pour Mitsu et Bombardier sur un fond "Timing" favorisant un peu Bombardier ... qui vient juste d'accrocher son Wagon ! Plus un bon compte rendu des essais 747-340 ! Et qq indications sur les voies suivies pour les futurs développements ! L'aéro et le cooling interne oui ! Les combustors oui ! Et le réducteur à l'air de tenir ... et de ne pas chauffer tant que celà ! Les Fans ... balancent entre 2 technos ... Et pas grand chose côté T° de combustion, pour ne pas charger la maintenance peut être ... c'est bien, mais j'ai cru lire il y a qq temps que MTU bosse dur sur les développements turbines P&W , pour vers 2015-16 ! Entre les lignes ... on peut penser que simplement P&W n'est pas prêt côté températures ... Peut être un développement futur, ils ne sont pas prêts, MTU pour 2012, c'est évident ..... Noté aussi que P&W prends les essais de "containment "au sérieux ! Rien pour les 737 Ou le 320 .... mais, à ce niveau de développement du GTF, pour Bombardier et Mitsu, si A et B sont intéressés, les 15% demandés pourraient ne pas être loin ! S'ils s'en occupent, P&W, c'est peut être secret défense ..... garder un oeuil sur la question quand même !!!! ---------------------- Extrait de AIN ----------------------- http://www.ainonline.com/news/single-ne ... -c-series/ All told, the performance of the fan, of the low-pressure compressor and the fan-drive gear system met or slightly exceeded Pratt’s commitments for the MRJ and C Series, according to Saia. Cold-soak testing at altitude also confirmed that the GTF showed no less ability to perform a quick windmill start than a conventional engine. In fact, he said, it usually started a second or two faster than the average 60- to 65-second start times of a conventional engine. Meanwhile, tests on the thermal management system–largely a measurement of the difference between the temperature of the oil going into the fan drive gear system and the oil coming out–showed that gearbox heat rejection proved 6 percent less than engineers predicted, allowing designers to reduce the size of the heat exchanger. “Gear efficiency stayed stable from first flight to the 39th flight,” said Saia. “We found no degradation at all.” When Saia spoke with AIN in early March, he said he expected his engineers to have completely disassembled the gear system by the end of the month for a close inspection of any wear not implied in the temperature calculations. Using an all new “centerline” core, the PW1000G’s new compressor has undergone both new-condition testing and end-of-service clearance measurements, said Saia. Tests conducted on the new combustor installed on a PW6000 found that it yielded a 50-percent reduction in NOx, he added. The new turbine uses a completely new aerodynamic geometry to add efficiency and minimize airfoil count. Finally, a new internal cooling scheme has yielded more effective cooling without using more air, said Saia. Still undetermined remains what material Pratt will ultimately use for the fan blades, as it continues projectile testing on a proprietary hollow metallic design and a composite construction in Connecticut. Saia said a decision should come by the middle of the year. “It’s a pretty close horserace right now,” he said. “They both have features of merit, but we’ve got to get through these laboratory tests to really qualify the material…Whichever one we select we’ll probably still keep the other one working just because there might be an application on either a smaller engine or a bigger engine, where having a material substitution will help us for another model.” The company also continues to evaluate the respective merits of two different composite chemistries for the fan containment case, and plans to perform ballistic testing on each during the second quarter. --------------------------------------------- Et copié d' Aviation Week ... Pratt & Whitney designed its PurePower PW 1000G (geared turbofan) engine with maintenance in mind . . . from using fewer airfoils (shaped surfaces that produce lift and drag when moved through the air) to boosting on-wing serviceability. Bob Sais, Next Generation Product Family vice president for Pratt’s Commercial Engine Programs, said the company also didn’t include exotic materials in its PurePower engine because customers are generally more concerned about lowering maintenance costs than running engines hotter. Saia said Pratt estimates operators in Europe will save $1.88 million per aircraft powered by the PW 1000G per year compared to similar thrust engines. This savings comes from fuel savings, noise fees, emissions and maintenance costs. In the U.S., because of lower noise fees, the estimated savings is $1.33 million. (Aviation Week) _________________ JPRS |
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Vincent
Inscrit le 23/08/2005 |
# 23 avril 2009 16:12 | |
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