Gran Capitan

Hybride d'helicoptère et d'avion

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Un autre projet compound de Chinook proposé fin janvier 2009 par Piasecki :

http://www.flightglobal.com/articles/2009/01/26/321544/piasecki-reveals-new-look-for-hot-rod-chinook.html

http://www.flightglobal.com/assets/getAsset.aspx?ItemID=27219

avec une augmentation de lift de 30% et de vitesse jusqu'à 250 kt

http://www.flightglobal.com/assets/getAsset.aspx?ItemID=27218

Piasecki Aircraft has revealed new images of a Boeing CH-47 Chinook transport helicopter augmented by ducted-fan thrusters, which can be vectored to boost maximum speed to 250kt (462km/h) or lift capacity by 30%.

The conceptual drawings, which reveal twin thrusters mounted on either side of the Chinook's mid-fuselage, were made public in a patent application published in mid-January. According to Piasecki's description, the vectored thrust is controlled by differential pitch propellers and horizontal vains.

The patent filing is an extension of Piasecki's ongoing experiments with the X-49A vectored thrust ducted propeller system, a Sikorsky UH-60 modified with a tail-mounted ducted fan and wings.

Piasecki

© Piasecki

So far, the US Army has not created a requirement to augment the speed or lift capability of its helicopter fleet. However, Boeing acknowledges making a "minor" investment in the Piasecki project. In an interview, Phil Dunford, vice-president and general manager for Boeing Rotorcraft, said the compound rotor concept has potential.

"There is a potential for the compound to be a capability that extends the current configuration of our aircraft into something quicker, with modifications to our aircraft that aren't as big maybe as a brand new programme," Dunford said.

Toutefois on peut rappeler qu'EADS est aussi en discussion avec Boeing sur le projet d'hélico lourd , mais que le Chinook est le moins intéressant des 3 sur la charge utile : cette technologie le rendrait plus compétitif et ramènerait sa charge utile autour de celle d'un VAB (mais son espace cargo est par contre trop limité : Internal Length 9.3m ; Internal Width 2.3m ; Internal Height :

2m)

A suivre ?

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une maquette d'un projet Viper cobra VTDP :

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Piasecki and Boeing also schemed this VTDP-equipped compound helicopter, the Viper Cobra, "a couple of years ago" as a high-speed escort for the US Marine Corps' MV-22 Osprey tiltrotor. The fuselage is new, but the rotor comes straight from the Chinook and cockpit from the Bell AH-1W SuperCobra.

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A&C en parle suite à une gaffe de Rolls-Royce. Les deux hélices propulsive et anticouple sont là pour contrer le brevet de sikorsky

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Peut-être (enfin ?) qq chose du côté d'eurocopter avc cet X3 dont on ne sait pas grand chose qui serait évoqué à héli expo 2009

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http://www.flightglobal.com/blogs/the-dewline/2009/02/heli-expo-r-r-lifts-veil-on-eu.html

Finalement on est plus dans la logique du fairey rotodyne que d'un hélicoptère léger d'attaque comme Sikorsky et Piasecki :

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Plus dans ce type d'appareil comme le Carter Copter :

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que dans cette variante du X2 :

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C'est toutefois bon signe que le premier constructeur mondial ne se désintéresse pas du créneau des hélos plus rapides :

une machine comme le tigre pouvant se cacher dans les aspérités du relief mais aussi échapper à des tirs en prenant de l'altitude rapidement serait vraiment très redoutable...

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Peut-être (enfin ?) qq chose du côté d'eurocopter avc cet X3 dont on ne sait pas grand chose qui serait évoqué à héli expo 2009

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http://www.flightglobal.com/blogs/the-dewline/2009/02/heli-expo-r-r-lifts-veil-on-eu.html

On commence à en savoir un peu plus :

un "hélicoptère hybride" de 8t , 16 m de diamètre et 220 kt de vitesse max.

Toutefois le brevet ci dessous , en français et datant de novembre 200 8, verrouille toute une gamme avec ailes hautes, basses,

mais aussi avec 2 hélices propulsives latérales ou une seule .

L'essentiel du brevet portant sur une chaine cinématique entrainant le rotor et la ou les hélices propulsives dans un rapport de proportionnalité.

Il n'y a donc pas 2 systèmes de moteurs entrainant l'un le rotor et l'autre les hélices.

http://v3.espacenet.com/publicationDetails/originalDocument?CC=WO&NR=2008142257A1&KC=A1&FT=D&date=20081127&DB=EPODOC&locale=en_GB

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Finalement tout le monde revient au Fairey Rotodyne, une machine des années 1960 qui déjà battait des records à l'époque. On n'a pas trouvé mieux depuis. http://en.wikipedia.org/wiki/Fairey_Rotodyne

Les projets similaire au Rotodyne existent mais ils sont rejetés par les grandes compagnies car moitié avion, moitié hélicoptère, ils ne rentrent pas dans la bonne "case" et chacun défend sa chapelle du tout avion (STOL) ou du tout hélicoptère (à rotors basculants comme le V-22 ou à rotors contrarotatifs comme le X2)... espérons un peu plus de courage et d'innovation du coté d'eurocopter !

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D'autant que ces diférents projets me semblent techniquement plus simple et plus sûr que les V-22 et autres versions à rotors basculants !

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Finalement tout le monde revient au Fairey Rotodyne, une machine des années 1960 qui déjà battait des records à l'époque. On n'a pas trouvé mieux depuis. http://en.wikipedia.org/wiki/Fairey_Rotodyne

Les projets similaire au Rotodyne existent mais ils sont rejetés par les grandes compagnies car moitié avion, moitié hélicoptère, ils ne rentrent pas dans la bonne "case" et chacun défend sa chapelle du tout avion (STOL) ou du tout hélicoptère (à rotors basculants comme le V-22 ou à rotors contrarotatifs comme le X2)... espérons un peu plus de courage et d'innovation du coté d'eurocopter !

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D'autant que ces diférents projets me semblent techniquement plus simple et plus sûr que les V-22 et autres versions à rotors basculants !

le rotor est entrainé par un turbopropulseur ? ou il utilise une partie des l'énergie des turbopropulseur existant ?

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le rotor est entrainé par un turbopropulseur ? ou il utilise une partie des l'énergie des turbopropulseur existant ?

Ni l'un, ni l'autre.

Dans le Fairey Rotodyne, un mélange d'air et de carburant est injecté dans des moteurs de fusées fixées aux extrémités des pales. C'était bruyant (même pour l'époque).

Ce système n'est pas efficace question consommation de carburant mais il n'est utilisé que pendants les atterrissages et décollages. Durant le vol, le Rotodyne se comportait comme un avion normal. Donc la consommation de carburant durant le trajet complet était inférieure à celle d'un hélicoptère.

Depuis cette époque de nombreuses sociétés proposent de faire revivre le concept. La plus connue, GBA (Groen Brothers Aviation),  propose de convertir des avions existants en Rotodyne( le C-130, ...). Elle a obtenu un contrat de la DARPA pour réaliser un prototype basé sur un jet de tourisme.

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Malheureusement, la société GBA a échoué a réaliser son prototype et est au bord de la faillite. Le point le plus bloquant était le bruit.  :O

Pourtant, c'était un appareil pour les militaires qui sont moins sensibles à ce genre d'arguments. ;)

J'ai peur que la majorité de ces projets ne proviennent de PME. Ils sont bons sur le papier en théorie. Mais combien de ces PME sont capables de voir tous les problèmes et de faire passer toutes les étapes d'un développement à leurs idées? :'(

Les grandes sociétés ne sont pas toujours mieux. Boeing a fait des superbes présentation de son X-50 Dragonfly. Un autre développement pour la DARPA...

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Les deux prototypes se sont écrasés et le programme est abandonné... :-[

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Un exemple de ce que pourrait être une application du VTDP au Cobra :

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US Army contract to develop a compound helicopter incorporating the Piasecki Vectored Thrust Ducted Propeller (VTDP) concept for the AH-64 Apache and AH-1W SuperCobra is nearing completion. Programme objectives have been met or exceeded by both the AH-64 VTCAD and AH-1W VTCAD configurations, resulting in increased maximum level flight speed to over 370km/h; 50% improvement in longitudinal acceleration and deceleration capability in level flight; 50% decrease in turn and pull-up radius at speeds in excess of 175km/h; and handling qualities that are at least as good as those of the baseline AH-64 Apache and AH-1W SuperCobra. In addition, tactical simulations have confirmed superiority of VTCAD over standard Apache and AH-1W SuperCobra. A separate US Navy contract involves investigation into application of VTDP technology to the AH-1W(4BW) four-blade rotor configuration. The Navy contract also includes ground testing of the full-scale VTDP and additional flight controls simulation and testing of the 4BW/VTDP configuration. Piasecki has also proposed flight demonstration of this technology on an AH-1W(4BW) to the Navy.

Le problème est que le projet date de 1996...

Sauf que depuis il y a le X-49A

à suivre

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http://www.aviationweek.com/aw/blogs/defense/index.jsp?plckController=Blog&plckScript=blogScript&plckElementId=blogDest&plckBlogPage=BlogViewPost&plckPostId=Blog%3a27ec4a53-dcc8-42d0-bd3a-01329aef79a7Post%3a3c4293b5-65e7-4bc0-87bc-ef3e73332cd9

 

It's a Helicopter, it's an Aeroplane...it's DiscRotor

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DARPA's DiscRotor program is up and running - you can check the official website here. It's an effort - and not the first - to combine the vertical take-off and landing capability of a helicopter with the high speed and maneuverability of a fixed-wing aircraft. It might be the first to combine a retractable rotor that stops and stows with a swept wing and ducted propellers. And it doesn't have a tail.

Stopped rotors are not new. Neither are stowed rotors, or telescoping blades. But relatively little has made it off the drawing board and into the wind tunnel, let alone into flight. According to my ever-helpful vertical-flight history guru, the first disc-rotor may have been a compound helicopter studied in 1935 by Danish aviation pioneer Jacob Ellehammer.

The idea of stopping the rotor and turning it into a wing has been tried several times over the years, starting in 1937 with the Herrick Vertaplane, which converted only from fixed- to rotary-wing mode. After a few dead ends along the way - the Hughes XV-19A hot-cycle rotor/wing and the Sikorsky X-Wing among them - the stoppable rotor did get airborne, but only as far as hover. DARPA's canard rotor/wing Boeing X-50A Dragonfly flew in 2003, but both unmanned demonstrators crashed before transitioning to fixed-wing flight.

Telescoping blades also have a long history - it seems helicopter pioneer Arthur Young filed a patent for a variable-diameter rotor in 1962 and his VDR was tested on a Bell 47. Sikorsky has also studied variable-diameter rotors and tiltrotors. Germany's Bolkow even windtunnel-tested an extendable rotor/wing concept in 1958 (it was to be a rocket/ramjet-powered interceptor with tip-mounted rockets that turned the telescoping wing into a rotor for vertical landing - enough said.)

DARPA's DiscRotor program is intended to determine if the concept is feasible, and whether the drag of the disc and weight of the blade retraction mechanism and the cross-shafting required to drive the ducted props can be kept low enough to produce a practical vehicle. The promise is a 400kt cruise speed and significant maneuverability in fixed-wing mode and a helicopter-like disc loading and hover performance in rotary-wing mode. There is no talk of a flight demonstrator yet, only windtunnel tests to measure drag and look at transition.

There are a few disc-rotor concepts already out there, as this video from Gerbino Flight Systems illustrates. It's about 8 minutes long, but stick with it to see what can only be described as a VTOL version of that fine Australian flying machine, the GAF

http-~~-//www.youtube.com/watch?v=TN_yvkcoihA

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En tout cas, un concept qui mériterait de sortir des cartons et avec un peu d'audace et un prototype comme démonstrateur ça pourrait faire changer les mentalités sur les appareils hybrides !

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il pourrait faire awacs en meme temps  :lol:

C'est exactement ce que j'ai pensé en voyant le concept.

Le problème c'est qu'une configuration d'avion classique avec des ailes nuit à la portance du rotor, c'est compliqué de concilié les 2 sans faire de sacrifices, sinon ces hybrides seraient déjà entré en service.

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Sikorsky unveils mock-up X2 armed scout

By

Stephen Trimble

on May 4, 2009 1:39 PM | Permalink | Comments (0) | TrackBacks (0) |ShareThis

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Sikorsky today has unveiled this mock-up for a light tactical helicopter (LTH) based on the X2, a developmental coaxial rotor aircraft capable of 250kts.

The unveiling comes at the Army Aviation Association of America convention in Nashville.

The X2 LTH is likely Sikorsky's prime candidate for the Army's armed scout helicopter contract. The at least 18-month delay for the ASH program announced last week should help Sikorsky's chances. The company needs the time to continue testing the X2 prototype, which first flew late last year.

http-~~-//www.youtube.com/watch?v=oLNyiqB7jgE

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Après cette adaptation réaliste pour un future proche relativement du proto X-2

voici un you tube "future aviation" avec au début un concept proche du défunt X-50 dragonfly de rotor transformable en ailes fixes qui renvoie au hypothèse d'un Escort V-22.

par contre la suite dérive dans des concepts à la Star War ... sympa à regarder mais bon, pas tout à fait pour tout de suite...

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le début est extrait d'un film avec sharzy "6th day"

Schwarzy ! Pour un Alsacien tu as oublié comment cela s'écrit  :lol:

Tu vas voir Wolfmoy, BPCs va finir par nous faire un montage vidéo de tous les films de SF et séries fantastiques pour nous présenter les Viper de Galactica Battle star, les Faucon Millenium de Star Wars, les aéronefs de Stargate Atlantis, les prototypes de Terminator, les ... :lol:

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Schwarzy ! Pour un Alsacien tu as oublié comment cela s'écrit  :lol:

Tu vas voir Wolfmoy, BPCs va finir par nous faire un montage vidéo de tous les films de SF et séries fantastiques pour nous présenter les Viper de Galactica Battle star, les Faucon Millenium de Star Wars, les aéronefs de Stargate Atlantis, les prototypes de Terminator, les

BD-5 comme dans JAMES BOND...

Plus sérieusement le X2 LTH ferait un très bon candidat comme appareil  d'escorte du V-22

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Plus sérieusement le X2 LTH ferait un très bon candidat comme appareil  d'escorte du V-22

je ne connais pas leur vitesse de croisière respective mais le X2 c'est 250kts max ( a quelle altitude ) et l'Osprey c'est 300kts a je ne sais qu'elle altitude ( plafond max FL250 ) pas sur que les deux soient compatibles  :rolleyes:

sinon le concept est sympa mais c'est un Kamov mieux profilé et avec un turboprop propulsif  :lol: ............

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je ne connais pas leur vitesse de croisière respective mais le X2 c'est 250kts max ( a quelle altitude ) et l'Osprey c'est 300kts a je ne sais qu'elle altitude ( plafond max FL250 ) pas sur que les deux soient compatibles  :rolleyes:

sinon le concept est sympa mais c'est un Kamov mieux profilé et avec un turboprop propulsif  :lol: ............

C'est clair que ce n'est pas tellement mieux qu'un Kamov dont j'ai même vu une photo d'un Ka-50 avec mini-ailes pour en améliorer la vitesse.

Et puis avant il y avait le Cheyenne

Actuellement le VTDP de piasecki

et peut être l'hybride X3 de Europter

Et si on rajoute le projet de "future lynx" compound avec des ailes et une transformation en cours de vol des turbines en jet (un peu comme le premier concept du youtube "future aviation" - excuse moi philippe je ne sais pas tronçonner les vidéos de youtube pour ne pas faire du HS :lol:)

Et bien on a fait le tour des solutions hybrides pour hélico

qui ont tout une caractéristique majeure :

N'avoir pas été mise en production !

Sauf le V-22 Osprey qui va peut être modifier la donne via ses RETEX :

"“The way the Osprey collapsed the battle space in al Anbar -- in fact, indeed throughout all of Iraq -- is really something that amazed those who saw it perform,” he said. “The aircraft has tremendous range, and [impressive] speed with which it moves around the operational area.”

For example, Trautman said one of his commanders told him that when the Osprey arrived in Iraq, it turned his battle space from the size of Texas into the size of Rhode Island.

The Osprey’s speed and range, Trautman said, means a lot more support for Marines on the ground."

Ce qui pour une fois pourrait donner une (nouvelle) chance à un hybride en confirmant l'intérêt de l'augmentation de la vitesse, comme au niveau des débouchés civils il y a aussi un marché pour les plateformes pétrolières de plus en plus éloigné, peut être qu'enfin le marché va basculer...

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je ne connais pas leur vitesse de croisière respective mais le X2 c'est 250kts max ( a quelle altitude ) et l'Osprey c'est 300kts a je ne sais qu'elle altitude ( plafond max FL250 ) pas sur que les deux soient compatibles  :rolleyes:

sinon le concept est sympa mais c'est un Kamov mieux profilé et avec un turboprop propulsif  :lol: ............

Pour le V-22 Escort les pré requis étaient :

The basic mission requirements and constraints dictate that the vehicle must:

    * Be capable of operating from the same class of Navy ships as the V-22 (LHA, LPH, and LHD). I.e. - must be able to fit into the ship elevators and hanger decks.

    * Have a two-man crew.

    * Have a maximum hover-out-of-ground-effect(HOGE) disc loading of 20 lbs/ft2 at maximum takeoff gross weight (TOGW) to minimize erosion and blowing dust from unpreparedsurfaces during VTOL operations .

    * Have a vertical rate of climb (VROC) of at least 1,000 feet per minute at TOGW, standard sea level, maximum rated engine power (MRP).

    * Have a dash speed of at least 400 knots at an altitude of 3,000 feet, MRP.

    * Be able to sustain a 5.0 g turn at TOGW, flying at 250 knots at an altitude of 3,000 ft.

    * Have a weapons load consisting of: internal or turreted 20 millimeter cannon+1500 rounds of ammunition, 4 AIM-9L air-to-air missiles, and 4 AGM-114 air-to-ground missiles.

http://www.globalsecurity.org/military/systems/aircraft/v-22-escort.htm

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Pour le X2 on a un peu plus de détails sur la stratégie de Sikorsky :

" Originally Posted by Ares

May 4, 2009 - Watch out for on-the-spot reporting later from Bettina Chavanne at the Quad-A show, where Sikorsky has taken the wraps off a full-scale mockup of its X2 Technology Light Tactical Helicopter (LTH) concept.

A much smaller model of the coaxial-rotor LTH has been making the rounds of the shows for a year or so now, so the mockup's unveiling at the Army Aviation Association of America show is significant. The Army is looking for an armed reconnaissance helicopter to replace the cancelled Bell ARH-70, but says its recent request for information showed nothing was available off the shelf to meet its requirements. So it's gone back to square one and started a new analysis of alternatives.

Sikorsky, meanwhile, says it couldn't deliver the high-speed X2 LTH before 2017-18, so its strategy seems to be to offer the Army the carrot of a completely new capability - if it can soldier on for a few more years with a combination of Kiowa Warriors, Apaches and unmanned aircraft in the armed scout role. The X2 would bring high speed with helicopter agility and the ability to go from the hover to 250kt and back without any rotary/fixed-wing mode changes.

Sikorsky's X2 Technology demonstrator is due back in the air shortly after the final mods to prepare for high-speed testing - connecting the pusher prop, fairing over the rotor hubs and making the gear retractable. The company expects to pass its 250kt speed target by year end - which should mean the results will be available in time for consideration by the Army as it analyzes its alternatives."

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Des nouvelles d'uneautre voie dans les hybrides? plus proche du V-22 :

DATE:07/05/09

SOURCE:Flight International

Radical response

By Stephen Trimble

http://www.flightglobal.com/articles/2009/05/07/326090/radical-response.html

Stage lengths of between 185km (100nm) and 1,850km create a competitive problem for conventional air transport. For a typical 1-2h flight, would-be airline customers must pass through a non-flying gauntlet, from commuting to and from remote airports to facing clogged lines for security, check-in and baggage claim. It is often easier and cheaper to drive.

Now Abe Karem, a widely respected aerodynamicist and innovator, has entered the mix. As founder of Karem Aircraft, he has quietly launched a new programme called the TR53 AeroTrain, a 120-seat, optimum speed tiltrotor (OSTR) dedicated to solving the 185-1,850km air transport problem.

Since launching the programme last year, Karem Aircraft has started to acquire and build pieces of the TR53's advanced propulsion system, starting with the rotor and transmission.

...

The TR53 is the commercial spin-off of Karem's OSTR technology. Meanwhile, the US Army is also funding a Karem Aircraft/Lockheed Martin team to design the TR75, an OSTR with a 23m-diameter rotor to haul cargo. An advanced engine produced to support the army's Joint Heavy Lift (JHL) programme, if funded, may carry over to the civilian programme.

As the designer of the fixed-wing General Atomics Predator and rotary-wing Boeing A160 Hummingbird unmanned aerial vehicles, Karem has built a reputation over the past two decades as one of the US military's most technically agile and operationally successful innovators...

...Fairey cancelled the Rotodyne programme in 1962. The VTOL aircraft was doomed by its relatively slow cruise speed and the comparatively inefficient combination of a tip-jet driven rotor and twin propellers for vertical and horizontal propulsion. Military and airline orders were promised, but sales never materialised and the UK government withdrew funding support.

Karem's tiltrotor configuration is a seemingly unlikely approach to succeed where Fairey failed. The V-22 has proved valuable to the US Marine Corps and US Air Force as a uniquely capable transport. But the concept has not been embraced by airlines like previous military-proven technologies, such as jet transports.

According to Karem's approach, that failure is because the V-22 suffers from the same efficiency problem as helicopters. Their rotor speeds are relatively fixed to support vertical flight, leaving them grossly overpowered during cruise.

FUEL CONSUMPTION

As a result, rotorcraft are consuming substantially more fuel during cruise than a jet-powered fixed-wing aircraft. For example, says Karem, available seat-kilometre costs for a Sikorsky S-92 helicopter are more than 10 times greater than for a 737 on a similar journey.

Karem thinks he has solved this efficiency problem by inventing a method to change the rotor speed to support optimal levels for vertical lift and forward flight. OSTR technology also combines a light rotor system with stiff blades to achieve high efficiency over a range of speeds.

"The OSTR is about combining an efficient transport capability with a robust vertical take-off capability. One of the major challenges that must be overcome is the drastically different requirements on the rotor in hover and in high-speed forward flight," says Karem.

"To bridge this gap," he adds, "OSTR uses a variable speed rotor system that can vary RPM [revolutions per minute]. A cruise RPM might be 20-50% of a maximum hover RPM."

Karem has already worked to tackle this problem for helicopters with the A160, a long-endurance UAV helicopter. The A160 features a Karem-designed variable speed rotor system. The A160 has demonstrated unrefuelled flight of nearly 20h, and is perhaps capable of 30h flight.

http://www.flightglobal.com/assets/getAsset.aspx?ItemID=28837

"In the same way that moving from a turbojet to a turbofan increases efficiency, the large-diameter rotor of the TR53 effectively provides a very high bypass ratio," Karem says.

The trade-off for the improved efficiency of a 16.2m-diameter fan, which compares with 1.55m-diameter CFM56 turbofan, is a "small price" for speed. While the 737 typically cruises at Mach 0.8, the normal cruise for the TR53 would be limited to Mach 0.6.

In hover mode, the aircraft consumes fuel at significantly higher rates. But Karem noted that helicopter mode flight should represent a "relatively small percentage" of overall flight time given a well-executed operation. "It should be noted that turbofan engines are particularly inefficient in on-airport operations including taxi, take-off and landing and low-altitude flight," adds Karem.

The extra fuel required to perform hover operations can be offset in cruise, where the engine's higher bypass ratio should yield fuel savings compared with even the most modern narrowbody aircraft. That advantage mean fewer carbon dioxide emissions with even the TR53's initial engines being the Rolls-Royce AE1107C, says Karem.

...

Karem says that he has not formally started soliciting letters of intent from airlines. And Karem Aircraft has decided not to market or exhibit the aircraft at the Paris air show next month. "However," says Karem, "we feel strongly that AeroTrain will be a game-changer when it comes to passenger transport."

The "game-changing" description is not mere cliche. Technology is not the only barrier for the TR53 concept to be fully realised. It requires the air transport industry and regulatory structure to adapt to an aircraft that does not require airports or even runways.

...

This may be the catch. Even if Karem can master the technical challenge of proving an efficient tiltrotor, its acceptance could be limited without a radical change in his customer's behaviour.

Karem's military customer has the advantage here. Army officials are motivated to abandon their dependence on airports and runways, which must be obtained and then defended, to move people and equipment long distances.

ET POUR COMPARER AVEC L'A400M . LE PROJET DE TR-75 SOUTENU PAR LOCKHEED MARTIN  8)

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TR75: HIGH PERFORMANCE FOR THE JHL MISSION

• Optimum Speed technology for enhanced performance

• More cruise efficient than existing cargo aircraft

• Operational disc loading of a CH-53

• Unique design features for safety and fault-tolerance

• High survivability for future conflicts

• High-speed cruise capability - Mach 0.6 / 345 knots

• 41,000 foot cruise ceiling, pressurized cabin

• Flexible high capacity aerial tanker - land or sea based refueling of rotary or fixed wing aircraft

• Capable of carrying M2 Bradley and outsized payloads

• 36 ton payload capacity

AVEC DE SURCROIT UNE EVIDENTE FACILITE AU SEA BASING

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• Economical large commercial-vessel designs as basis

• Up to 600 vehicles in climate-controlled stowage

• Range and speed to accompany CVN task force

• 16 VTOL spots for TR75 aircraft

• Optional higher-density aircraft stacking and storage scheme

• Two patents pending

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http://www.aviationweek.com/aw/blogs/defense/index.jsp?plckController=Blog&plckScript=blogScript&plckElementId=blogDest&plckBlogPage=BlogViewPost&plckPostId=Blog%3a27ec4a53-dcc8-42d0-bd3a-01329aef79a7Post%3a22567a02-9a59-4e2a-8553-07e369cb2829

Encore un helo bizarre ... birotor transversal ... avec tilt wing mais pas pas tilt rotor ...

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Il semble que la bascule des ailes permette d'incilner les rotor un peut plus qu'a la normale accroissant leur role de propulsion ... et reléguant la sustentation aux ailes.

Aux allure plus faible les aile se redresse et les rotor reviennent "a plat" fonctionnant comme un helo classique avec juste un petit peut de portance des ailes braquées.

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