• Hi Guest! Forum rules have been updated. All users please read here.

US Joint Heavy Lift

yasotay

CLEARANCE: Top Secret
Senior Member
Joined
Oct 19, 2006
Messages
1,972
Reaction score
72
[quote author=CammNut]JHL - US Army-led programme for a heavy-lift rotorcraft able to carry Future Combat Systems vehicles around the battlefield; this is not yet a programme of record, and might yet be merged with AJACS; four concept design and analysis contracts, now completed, covered designs in two speed ranges - the Boeing Advanced Tandem Rotor Helicopter and coaxial-rotor Sikorsky X2 Technology Crane at the lower speed; the Bell Boeing Quad Tilt Rotor and Sikorsky X2 Technology High Speed Lifter at the higher speed; and Frontier Aircraft's Optimum Speed Tilt Rotor. Karem designed the precursor to the Predator UAV and the Frontier Systems (now Boeing) A-160 Hummingbird long-endurance unmanned helicopter, which has an optimum-speed (variable RPM) rotor. There is a patent for the OSTR rotor, but I have not found anything on the overall vehicle design for JHL.[/quote]

Actually there are five JHL concepts in three speed bands.

The Sikorsky X2 Lifter and Boeing ATRH (Advanced Tandem Rotor Helicopter) at <170 knots
The Sikorsky X2 High Speed Lifter in the 170-240 knot band
The Bell/Boeing QTR (Quad Tilt Rotor) and Karem Industries OSTR (Optimum Speed Tilt Rotor) in the 240-300(+) band.

All of the teams are now finishing their work on their concept aircraft.

As to the USAF doing ESTOL... exceedingly doubtful. Best they will do is STOL. Unless dictated to by outside forces they will not do SSTOL, ESTOL, or VTOL for a lifter.

On JMR, it may be an attack airframe, but there is also a more ambitious program to make it a common airframe for both attack and utility missions. This could range from just dynamic components (rotors, drivetrain, engines) on mission specific airframes or a return to a (Armed Utility and/or Mi24) concept that would fill a multitude of missions.
 

CammNut

CLEARANCE: Secret
Joined
Feb 1, 2007
Messages
296
Reaction score
3
Here is another of the JHL contenders - Boeing's Advanced Tandem Rotor Helicopter, supposedly drawing heavily on the design of the XCH-62 Heavy Lift Helicopter, which was built but never flown and last year was scrapped by the US Army's aviation museum in Ft Rucker because it had deteriorated dangerously...
 

Attachments

CammNut

CLEARANCE: Secret
Joined
Feb 1, 2007
Messages
296
Reaction score
3
Those of you following the Joint Heavy Lift (JHL) proeject will know that the "dark horse" in the race is Karem Aircraft's Optimum Speed Tilt Rotor (OSTR). Abe Karem designed the precursor to the Predator UAV, and the A160 Hummingbird long-endurance unmanned helicopter with optimum speed rotor (subsequently acquired by Boeing). Now Karem has applied the optimum speed concept to a tiltrotor.

The OSTR was one of five configurations studied under the 18-month JHL concept design and analysis phase that ended earlier in 2007 - and the most influential. The US Army Aviation Applied Technology Division took the results of the CDA studies and produced a "One JHL" design called the High Efficiency Tilt Rotor (HETR), which looks a lot like Karem's OSTR.

Now AATD plans to award three 24-month contracts to further refine tiltrotor configurations for an even larger, Airbus A400M-sized JHL: most likely the Bell Boeing Quad Tilt Rotor, Sikorsky Variable-Diameter Tilt Rotor - and Karem's OSTR. The plan is to select one for an X-plane flight demonstration by 2015.

Anyway, here are some images of the TRS65 OSTR from a presention given by Karem earlier this year:
 

Attachments

flateric

CLEARANCE: Above Top Secret
Staff member
Top Contributor
Senior Member
Joined
Apr 2, 2006
Messages
8,781
Reaction score
204
Very interesting - I'm thinking to dig into all old posts to get all JHL stuff gathered here. Dear Yasotay, can we hope that you will continue with the other JHL concepts studied - even if they were considered un-competitive ones? Of course, if this doesn't implement one's problems.
 

yasotay

CLEARANCE: Top Secret
Senior Member
Joined
Oct 19, 2006
Messages
1,972
Reaction score
72
Well I will be happy to post what I can, however Camm appears to know more than I.

"Sikorsky Variable-Diameter Tilt Rotor"

That was not one of the original five efforts. If this is in fact going to be funded then it is a new start to the JHL effort. I believe that the follow on work will involve the high speed efforts, as the requirements analysis has shown that for the distances they want to operate these aircraft (250NM radius at ~26 ton), the high speed concepts are more viable.

From David Harvey's column at the RotorHub-

AUSA: Bell’s Ewing Ties Quad Tiltrotor JHL Response To Realistic Appraisal Of Challenges.

Washington DC:- Bell’s Alan Ewing - in charge of the company’s quad tiltrotor development effort - says here that any flying prototype to emerge from current design studies will be limited to the power range of the current V-22 engines.

But scaling up beyond that will require a new engine initiative. Engines with the requisite power are out there, he says, but they will have to be modified and qualified to operate through the rotational angles required in a tiltrotor design.

Ewing shows that Bell (which is working with Boeing, but not yet on any type of formal business basis) is moving steadily ahead on the design challenges inherent in developing a vehicle capable of meeting presumed JHL (Joint Heavy Lift) targets.

A defined design requirement is awaited, but is still considered some way off while requirements issues are under study by various DoD and service agencies.

The Army, however, issued a statement at ‘AHS63' (The most recent AHS forum, held this past May in Virginia beach, Va.,) committing to tilt engine technology as the preferred approach of choice.

In the meantime, more detailed work that will lead to a preliminary design review next year is underway on what Bell is currently calling a ‘B2A-26-6' quad tiltrotor concept design - B2A for the second iteration of design, 26 for its payload (in tons) and 6 because it will be able to fly a 250nm radius at that weight at a density altitude of 6,000 ft.

But, Ewing stresses, the design group is ready to get working on whatever mission design emerges from the current joint requirements process. He anticipates the ‘quad’ could get larger as a result.

The design work facing the two manufacturers is enormous. Currently only about 30 engineers are engaged on the project, but Ewing says it will ramp up shortly and could reach 250-300 not far down the road.

Ewing admits aspects of the blade and hub design are still in early analysis to determine the types of loads and moments any design will incur.

Current thinking is targeting a four-blade layout 38 ft in diameter, but he admits that could change and go larger, again depending on requirements.

More precise information on the hub moments and other factors likely ‘seen’ by the design will emerge from NASA Langley wind tunnel testing set to begin later this year.

An associated problem is actuation of blades. ‘We have actuators now, so I don’t think scaling them will be a problem in terms of weight and drag,’ he told a meeting here.

Bell is studying two alternative ways to handle blade mounting - either as ‘gimbaled’ blades in case there’s a blade-fold requirement from the maritime community, or a design based on direct attachment elastomerics, along the lines of a hingeless blade configuration for a conventional helicopter.

Ewing updated the audience on how much detailed design - down to a frame-by-frame fuselage schematic - had been done in the last year. The baseline ‘B’ version was frozen this past March is awaiting an internal report.

He said Bell and Boeing are still some way away from defining work-share on the project and for now both are using ‘best practices’ as they work together on concept definition.

Bell management is scheduled to look at required ongoing investment to proceed to next steps next week, Ewing said. This stage will include a flight test of a 70 percent scale prototype perhaps within two or three years.

The US Army, meanwhile, is currently working to get kick-off funding for JHL prototype development into its key Program Objective Memorandum (POM) funding plans for 2010 onwards.

Although the Army will (notionally) become the main sponsor for JHL, Ewing confirms USAF has been requesting regular updates on the aircraft - which could end up operating routinely at 30,000 ft. ‘Although I have to say we haven’t been over there (to USAF) lately,’ he said.

In summary, Bell/Boeing’s work is an undeniably exciting project to anyone interested in the future of rotorcraft technology - a genuine push into a future replete with challenges in almost all the aerodynamic domains of the future.

The team has taken a long-term - visionary - view and as a result is clearly ahead of potential competitors in coming to terms with some of these issues.

It is a case study, perhaps, in how to ‘do’ aerospace R&D in the current environment - a commitment to company funded IRAD started early, and as realistically tied as Ewing and his team can calculate to breakthrough, future requirements.

‘We certainly are keeping going,’ he says, and we realise no models are perfect but some are useful,’ he commented wryly at he beginning of his presentation, drawing from a well known quotation.

Equally clearly this is no mere ‘scale-up’ of a V-22 either. It’s a whole new aerospace ‘big project’ in the making which Ewing admits will make heavy demands on the Bell and Boeing resource base.

- David S. Harvey
 

CammNut

CLEARANCE: Secret
Joined
Feb 1, 2007
Messages
296
Reaction score
3
Because the US Army only plans to look at tiltrotors for the next phase of JHL, and its X-2 Crane and X-2 High Speed Lifter are out of the running, Sikorsky plans to dust off its VDTR work (which ended in the late 1990s with windtunnel tests, I think) - although it will continue to refine the X2 designs in case something changes. Bell Boeing and Sikorsky also plan to take a closer look at AATD's HETR "reference design" to see if it is achievable.

They are waiting for a new performance specification from the Army, but they already know JHL will have to be bigger than C-130-size as the FCS vehicles are no longer 20t and more like 26t, heading for 30t.

I have some stuff on HETR, which I will post when I find it.
 

flateric

CLEARANCE: Above Top Secret
Staff member
Top Contributor
Senior Member
Joined
Apr 2, 2006
Messages
8,781
Reaction score
204
Before they gone, here they go as part of the past of JHL according to the last news.
These and other members of Sikorsky X2 family are here in dedicated thread started by CammNut

http://www.secretprojects.co.uk/forum/index.php/topic,2768.msg15857.html#msg15857

Joint Heavy Lift X2 Technology™ Crane

- 40 ton external lift
- Low life cycle costs
- Shipboard compatible
Efficient design
Very low empty weight fraction
- 0.47 at design gross weight
- 0.35 at max alternate gross weight
Excellent austere site capability
- Disk loading = 12 psf with load
- Only 7.5 psf without load
- Low tire footprint (CBR)
165 kt design cruise speed
Rapid load and unload
Low risk
Strong technical base for enabling technologies
Low unit cost

Weights
Design gross weight 106,800 lb
Max alternate gross weight 142,400 lb
Payload at design gross weight 40,000 lb
Empty weight 48,600 lb
Design mission fuel weight 15,800 lb
Rotors (each rotor)
Number of blades 3
Rotor radius 54 ft 1 in
Propulsion
Number of engines 2
Max rated power per engine (SLS/ISA) 10,500 shp
 

Attachments

flateric

CLEARANCE: Above Top Secret
Staff member
Top Contributor
Senior Member
Joined
Apr 2, 2006
Messages
8,781
Reaction score
204
Joint Heavy Lift X2 Technology™ High Speed Lifter

- 20 ton internal lift
- 240 kt cruise speed
- Shipboard capable

Helicopter-like attributes
- Hover efficiency
- Low-speed stability
- High speed without transition
- Maneuverability
- Agility
- Safe descent/autorotation
- Nap of the earth flying capability
Achieves 240 knot cruise capability
Simple rotor system
Auxiliary propulsion is clutched off in
hover and is not flight critical
Low vulnerable area

Weights
Design gross weight 158,400 lb
Max alternate gross weight 211,200 lb
Payload at design gross weight 40,000 lb
Empty weight 96,500 lb
Design mission fuel weight 19,500 lb
Rotors (each rotor)
Number of blades 4
Rotor radius 55 ft 0 in
Propellers (each propeller)
Number of blades 9
Propeller radius 5 ft 8 in
Propulsion
Number of engines 3
Max rated per engine (SLS/ISA) 13,900 shp
 

Attachments

yasotay

CLEARANCE: Top Secret
Senior Member
Joined
Oct 19, 2006
Messages
1,972
Reaction score
72
HETR = High Efficiency Tilt Rotor

It has, with more than a passing glance, a lot of similarity with the Karem OSTR, aerodynamically. The idea is that the government will take the best of each of the projects and include them in the new requirement.

While there is much discussion at having to go to 30 ton capability, the requirement has not gone to that. It is all very interesting, however without some serious engine S&T work, it is all moot.
 

yasotay

CLEARANCE: Top Secret
Senior Member
Joined
Oct 19, 2006
Messages
1,972
Reaction score
72
Found this over at Flightglobal.

http://www.flightglobal.com/articles/2006/11/07/210369/full-tilt-ahead-what-will-follow-the-v-22.html

The picture from flight I have but it is marked proprietary (as is most of my JHL material) :-\

Of all of the JHL efforts, the QTR is the most mature. Bell (and some Boeing) has been working on this concept for almost ten years.
 

Attachments

flateric

CLEARANCE: Above Top Secret
Staff member
Top Contributor
Senior Member
Joined
Apr 2, 2006
Messages
8,781
Reaction score
204
It's how all that started - from September 2005 Vertiflite. BTW, where's Mike Hirchberg? Haven't heard from him for a while
http://www.vtol.org/news/issues905.html

AATD Awards Joint Heavy Lift Contracts
http://www.boeing.com/news/releases/2005/q3/nr_050922p.html

The US Army Aviation Applied Technology Directorate, in cooperation with its Joint Service and NASA partners, has awarded five 18-month Concept Design and Analysis (CDA) contracts for a Vertical Takeoff and Landing (VTOL) Joint Heavy Lift, (JHL) rotorcraft. In order of their design cruise speeds, the five concept vehicles chosen for study are the:

Sikorsky X2C, X2 Technology Crane coaxial rotor (165 knots)
Boeing ATRH, Advanced Tandem Rotor Helicopter (165 knots)
Sikorsky X2HSL, X2 Technology High Speed Lifter advancing blade compound helicopter (245 knots)
Bell Boeing QTR Quad Tilt Rotor (275 knots)
Frontier Aircraft OSTR Optimum Speed Tilt Rotor (310 knots).


The CDA contracts are for conceptual/preliminary design of a baseline aircraft and specific design excursions to identify the impact of payload, range, environmental conditions, and shipboard compatibility on aircraft size, performance, operational suitability, cost, schedule, and development risk. The is a JHL VTOL rotorcraft that supports future Joint concepts of operations (CONOPS). These include mounted and dismounted vertical envelopment; executing operational maneuver and sustainment operations at extended ranges simultaneously into unprepared, complex terrain locations under extreme environmental conditions; and overcoming enemy anti-access strategies in Joint expeditionary operations from land and sea bases.

The JHL baseline design specification is to carry an FCS/Stryker/LAV Vehicle over a 250 nautical mile (nm) radius, under 4000 foot density altitude and 950 Fahrenheit (4k95) conditions, from/to land or sea bases and operating areas. Eight specific excursions to these conditions will also be investigated that include lighter and heavier cargo (16 to 26 tons), shorter and longer mission radii (210 to 500 nm), more extreme environmental conditions (6,000 ft at 95�F), and full compatibility with a future ship.

The CDA is part of the overall multi-year (FY05-07) JHL Concept Refinement effort focused primarily on supporting the joint requirements definition process. The CDA is the technical pillar of activity designed to inform the joint requirements analysis with credible rotorcraft design concepts and performance projections that can reasonably be matured to a Technology Readiness Level 6 by 2012.

The CDA contracts deliverables include aircraft designs with substantiating data, a specification document, a technology development strategy, and cost/schedule estimates for a Component and Technology Demonstration phase in a large-scale flight vehicle.

###



Boeing receives two study contracts from U.S. Army for Joint Heavy Lift

Sept. 23, 2005 -- The U.S. Army has awarded Boeing [NYSE: BA] two contracts to perform conceptual design and analysis of vertical-takeoff-and-landing concepts for the Joint Heavy Lift (JHL) program.

One contract, worth $ 3.4 million, goes to Boeing Phantom Works for its Advanced Tandem Rotor Helicopter (ATRH). Boeing proposed the ATRH in the Army's low-speed category, which is for vehicles that fly between 160 and 200 knots.

The other contract, worth $3.45 million, goes to the team of Bell Helicopter, a Textron company (NYSE: TXT), and Boeing Phantom Works for the QuadTiltrotor (QTR) aircraft, which was entered in the high-speed category of 250 knots or more.

"These awards are important first steps toward defining a next-generation military weapon system -- and a great opportunity to demonstrate how cutting edge technologies can be applied to meet joint service needs," said Ron Prosser, Boeing Phantom Works vice president and general manager of Integrated Defense Advanced Systems. "Boeing has been developing multiple configurations to help our customer better evaluate its requirements for Joint Heavy Lift."

The Boeing Advanced Tandem Rotor Helicopter exploits the system maturity, the extraordinary VTOL cargo-handling versatility and the unsurpassed maritime suitability of the tandem rotor platform, which uses two equally-sized rotors that spin in opposite directions for lift.

The ATRH will maximize the benefits of advanced technologies and lean approaches, and will capitalize on emerging technologies that improve weapons system effectiveness and operational costs.

Bell Boeing's QuadTiltrotor is an evolutionary application of the tiltrotor technology utilized in the V-22 Osprey. The QTR is a tandem-wing, four-proprotor aircraft with a large cargo fuselage and a rear-loading ramp.

Four turboshaft engines, each mounted in one of four tilting wingtip nacelles, power the proprotors through interconnected transmissions for redundancy. The QTR design will be sized, refined and analyzed over the next 18 months to determine program requirements and feasibility of further development.

The purpose of these contracts, according to the Army, is to define the "art of the possible," the "science of the probable" and the "design of the affordable" for a JHL VTOL rotorcraft that enables future joint concepts of operations.

Contractors will provide preliminary conceptual/preliminary designs for baseline aircraft, and will identify the impact of variations in payload, range, environmental conditions and shipboard compatibility on aircraft size, performance, operational suitability, cost, schedule and development risk. Each award is for 18 months.

The Boeing Phantom Works participation is through its Advanced Rotorcraft Systems team. Phantom Works is the advanced research and development unit and catalyst of innovation for Boeing. It provides advanced system solutions and innovative, breakthrough technologies that reduce cycle time and cost while improving the quality and performance of aerospace products and services.

Through its Integrated Defense Advanced Systems group, Phantom Works provides these system and technology solutions to Boeing Integrated Defense Systems, one of the world's largest space and defense businesses.
 

hesham

CLEARANCE: Above Top Secret
Joined
May 26, 2006
Messages
23,872
Reaction score
922
Hi,

the USA new projects,AMT-T;ATT and AMT-H.
http://www.globalsecurity.org/military/systems/aircraft/amt.htm
 

Attachments

yasotay

CLEARANCE: Top Secret
Senior Member
Joined
Oct 19, 2006
Messages
1,972
Reaction score
72
Actually hesham those are all ancient pictures of concepts that are now part of the Joint Heavy Lift effort being worked on in the US.
 

F-14D

I really did change my personal text
Senior Member
Joined
Oct 4, 2007
Messages
1,731
Reaction score
8
As has been posted elsewhere, the Army has now eliminated all concepts except Tilt-Rotor for being unable to meet the requirements (there is more than one Tilt-Rotor concept in contention), especially if the payload required increases. Bell Boeing are now offering two Quad Tilt-Rotors, depending on the payload Army wants.

.
 

Attachments

LowObservable

CLEARANCE: Top Secret
Senior Member
Joined
Oct 18, 2006
Messages
2,169
Reaction score
24
Yasotay - My point is that, in my considered opinion, a 30-ton-payload Quad Tilt Rotor is not a realistic idea. Let alone statements that it will cost no more than an A400M.
 

fightingirish

CLEARANCE: Top Secret
Senior Member
Joined
Jun 3, 2006
Messages
2,133
Reaction score
103
This picture of the Boeing ATRH concept is featured in Popular Mechanics.



Source: http://www.popularmechanics.com/technology/military_law/4245924.html?series=36

Edit: Picture not more available at Popular Mechanics.
 

Attachments

TinWing

CLEARANCE: Top Secret
Senior Member
Joined
Jan 3, 2006
Messages
888
Reaction score
9
LowObservable said:
Yasotay - My point is that, in my considered opinion, a 30-ton-payload Quad Tilt Rotor is not a realistic idea.
Realistic? Not in the least.


LowObservable said:
Let alone statements that it will cost no more than an A400M.
Well, in truth, the A400M is going to cost a great deal more than originally anticipated, closer in magnitude to the C-17 than the C-130J. The current exchange rate environment is working against Airbus on every level.
 

yasotay

CLEARANCE: Top Secret
Senior Member
Joined
Oct 19, 2006
Messages
1,972
Reaction score
72
TinWing said:
LowObservable said:
Yasotay - My point is that, in my considered opinion, a 30-ton-payload Quad Tilt Rotor is not a realistic idea.
Realistic? Not in the least.


LowObservable said:
Let alone statements that it will cost no more than an A400M.
Well, in truth, the A400M is going to cost a great deal more than originally anticipated, closer in magnitude to the C-17 than the C-130J. The current exchange rate environment is working against Airbus on every level.
Interesting. I would certainly to see some empirical data to support it being unrealistic. I have been through enough meetings and reviews (and grillings of industry) to believe that it is possible. I will agree that an engine capability is required for some of the concepts (but not all). 30 ton is to allow for weight growth over the life span and to pick up the heaviest of the FCS. Most of the lift is for 24-26 tons. The real VTOL requirement is for mid point so STOL TO is likely at max gross. I would not pretend to tell you that the aircraft will not be expensive, however the capability to not be reliant on fixed facilities and all the modern badness attendant in them is what drove the US Army to look in this direction in the first place. Not to mention on ships (NAVAIR has actually done the math and said it can be done).
 

LowObservable

CLEARANCE: Top Secret
Senior Member
Joined
Oct 18, 2006
Messages
2,169
Reaction score
24
I think many things are possible, in terms of the sheer technical ability to do them. And the QTR has the advantage of splitting the lift four ways and thereby steering clear of the problems of vast torque.
I do think it's going to be hugely expensive and complex, and the risk (as with V-22, as with F-35B) is that containing OEW is extremely challenging and absolutely necessary, because significant OEW growth, in a machine that already has a high OEW fraction, quickly eats all the payload.
Operationally, the issue is one mentioned in terms of the Mil V-12 (and analogous to "LO's Unifying Theory of Why Civil VTOLs Don't Work"). Once you've got enough space for a few of these monsters to play around it, you don't need much more space to put in a 750-foot runway, and other options open up.
 

yasotay

CLEARANCE: Top Secret
Senior Member
Joined
Oct 19, 2006
Messages
1,972
Reaction score
72
LO - I will have to think about the space comments for civil work. I can agree with you that getting acceptance with the civil crowd for anything with propellers is a challenge these days. I don't know if you have seen any of the work NASA has done in the last few years regarding STOL and VTOL to alleviate congestion in the major air hubs, there is some compelling data their. It would likely be as valid for SSTOL as it would be for VTOL

Interestingly I will tell you that one of the points made to the USAF about large VTOL over large STOL is that in the space that it takes to land one (USAF standards) STOL platform you can with a wide safety margin land as many as ten VTOL (even QTR). So a MOG one landing point for a fixed wing is a MOG ten for VTOL. Also without requirements for back taxi and off load area (VTOL is not as particular about the status of the landing strip) they could off load in far less time than the fixed wing. Just to poke fun, the Army showed how a normal eighteen hole golf course could be used to land a mechanized battalion in a fraction of the time needed to do so with fixed wing... even if they could make the Par 4 dogleg left.
 

F-14D

I really did change my personal text
Senior Member
Joined
Oct 4, 2007
Messages
1,731
Reaction score
8
yasotay said:
LO - I will have to think about the space comments for civil work. I can agree with you that getting acceptance with the civil crowd for anything with propellers is a challenge these days. I don't know if you have seen any of the work NASA has done in the last few years regarding STOL and VTOL to alleviate congestion in the major air hubs, there is some compelling data their. It would likely be as valid for SSTOL as it would be for VTOL

Interestingly I will tell you that one of the points made to the USAF about large VTOL over large STOL is that in the space that it takes to land one (USAF standards) STOL platform you can with a wide safety margin land as many as ten VTOL (even QTR). So a MOG one landing point for a fixed wing is a MOG ten for VTOL. Also without requirements for back taxi and off load area (VTOL is not as particular about the status of the landing strip) they could off load in far less time than the fixed wing. Just to poke fun, the Army showed how a normal eighteen hole golf course could be used to land a mechanized battalion in a fraction of the time needed to do so with fixed wing... even if they could make the Par 4 dogleg left.
Mostly agree with this. Couple of thoughts. Regarding civil and propellers, with fuel being where it is, turboprops for regional use are selling like mad, and the 50 seat regional jet market has collapsed. There is another problem with civil VTOL. The increased margins required for civil operation aren't that much of a problem. The problem is the with the Neanderthals in local governments and the NIMBY or BANANA groups that won't allow heliports to be built or used. A CTOL is almost always more efficient than a VTOL, as long as you happen to have airports where you need them. If the has to always operate from an airport, then the economic justification for their operation goes away. The situation in Eurpoe is even more restrictive than it is in the US, sadly.

True STOL operations is even more of a non-starter for larger craft. Aside form the problems mentioned above, for true STOL operations passenger aren't going to put up with the rather violent conditions that occur in true STOL operations.

From the military point of view it's frankly more difficult to do true STOL (~750 feet) than it is to do V/STOL. Aside from how strong the aircraft has to be, you again have the violent maneuvering involved, which does wonders for securing your cargo, you've got to have clear areas at either end of your strip, so you can get down to the runway. A 750 foot strip carved out in a dense forest would really have ~ 500 feet available for STOL operatins, but would have 750 feet plus for VTOL.

Regarding the Army's JHL, at least one sign that it's feasible is that USAF is starting to find ways to kill it, including coming up with the "agile airlifter" concept, a critical requirement of which is that it has to be able to cruise at at least .82 Mach. JHL can't possibly do this, but no one has actually explained why an airlifter needs that speed.

As far as QTR goes, it is not the only Tilt-Rotor technology in contention. Its advantage is not that it has the best Tilt-Rotor performance, but that it is the lowest risk. The original QTR proposals, in fact were based on a stock V-22 wing/engine setup in front and the same thing in the rear with a stretched span, married to a bigger fuselage. As Army's payload requirements rose, this changed to more new technology, but the concept is the same and the bidders are the most experienced. Another fortuitous circumstance is that since the Marines heavy lift requirement is so critical, they were allowed to proceed with their CH-53K program (which ironically is powered by the engines reportedly originally selected for the V-22). This impacted the JHL program in that, while JHL is still required to be shipboard operable, it is no longer certain that it will be required to be shipboard stowable, simplifying the wing/engine design considerably.

I don't see any particular problem in meeting A400M payload specifications. Tilt-Rotor is actually not that complicated. I also don't see any reason why the aircraft might not cost less than an A400M in constant dollars. With a multi-national R&D and production program, it pretty much always casts more than what it would cost if just one nation was involved. The benefit for the member nations is that each nation's portion should be less than what it would cost them to do it alone. This artificially raises A400M's price. But there's another factor that's often overlooked in these discussions. While JHL's payload my grow to rival that of A400M, no one has claimed the JHL will be able to do everything that A400M can do. To cite just one example, JHL's range will only be a fraction of that of A400M. That's all the Army needs for what it wants it for. Of course, JHL will be far better than A400M in carrying external loads or doing crane operations, but I doubt if A400M's designers are losing any sleep over that. :)

"...the Army showed how a normal eighteen hole golf course could be used to land a mechanized battalion..."? Now that was a big mistake in trying to sell the concept to USAF. They might even consider it sacrilegious to conduct flight operations from a golf course! I mean, next to the runway itself, what is more important at a base than the golf course?
 

yasotay

CLEARANCE: Top Secret
Senior Member
Joined
Oct 19, 2006
Messages
1,972
Reaction score
72
"From the military point of view it's frankly more difficult to do true STOL (~750 feet) than it is to do V/STOL. Aside from how strong the aircraft has to be, you again have the violent maneuvering involved, which does wonders for securing your cargo, you've got to have clear areas at either end of your strip, so you can get down to the runway. A 750 foot strip carved out in a dense forest would really have ~ 500 feet available for STOL operatins, but would have 750 feet plus for VTOL."

Your concept of STOL is at least far to low for the USAF (by at least half) and in fact is to short for even their SSTOL concepts. Needless to say, the Army is not impressed with USAF parameters.

"Regarding the Army's JHL, at least one sign that it's feasible is that USAF is starting to find ways to kill it, including coming up with the "agile airlifter" concept, a critical requirement of which is that it has to be able to cruise at at least .82 Mach. JHL can't possibly do this, but no one has actually explained why an airlifter needs that speed."

You have no idea how close to true that is. By the way USAF was not happy when shown that the MOG rate for VTOL made the Mach.82 irrelevant at anything under 600NM.

"To cite just one example, JHL's range will only be a fraction of that of A400M."

Only partially true. JHL has a requirement to be air refuel capable.

"...the Army showed how a normal eighteen hole golf course could be used to land a mechanized battalion..."? Now that was a big mistake in trying to sell the concept to USAF. They might even consider it sacrilegious to conduct flight operations from a golf course! I mean, next to the runway itself, what is more important at a base than the golf course? "


Yes I think that the Army briefer was physically thrown off the air base after showing such heresy, after which all of the 'blues' retired to the officers club to drown their consternation and ridicule the heathen they had allowed into their midst.
 

F-14D

I really did change my personal text
Senior Member
Joined
Oct 4, 2007
Messages
1,731
Reaction score
8
yasotay said:
"To cite just one example, JHL's range will only be a fraction of that of A400M."

Only partially true. JHL has a requirement to be air refuel capable.
[
You are, of course, 100% correct. My point was that the unrefueled range for a given payload would be far less than that of A400M, which is no problem for the users, given the role of JHL. Use of air refueling would be primarily for self-deployment.
 

hesham

CLEARANCE: Above Top Secret
Joined
May 26, 2006
Messages
23,872
Reaction score
922
Hi,

also from Flightglobal;
http://www.flightglobal.com/articles/2008/01/14/220796/heavy-duty-us-army-backs-tiltrotor-as-future-battlefield.html
 

Attachments

hesham

CLEARANCE: Above Top Secret
Joined
May 26, 2006
Messages
23,872
Reaction score
922
Hi,

the Boeing Advanced Civil Tiltrotor project.
http://www.flightglobal.com/pdfarchive/view/2002/2002%20-%203390.html?search=ducted%20prop%20aircraft
 

Attachments

yasotay

CLEARANCE: Top Secret
Senior Member
Joined
Oct 19, 2006
Messages
1,972
Reaction score
72
hesham said:
Hi,

the Boeing Advanced Civil Tiltrotor project.
http://www.flightglobal.com/pdfarchive/view/2002/2002%20-%203390.html?search=ducted%20prop%20aircraft
Alas, like the Sonic Cruiser, doomed before metal. Way to radical for consumers... and it has propellers for heavens sake! This is after all the 21st Century.
 

flateric

CLEARANCE: Above Top Secret
Staff member
Top Contributor
Senior Member
Joined
Apr 2, 2006
Messages
8,781
Reaction score
204
Damn, being a passenger, I'd think twice before going onboard. Even not watching Osprey fuselage AoA during climbing stage tonight. It looks damn dangerous, and QTR looks twice as.
 

fightingirish

CLEARANCE: Top Secret
Senior Member
Joined
Jun 3, 2006
Messages
2,133
Reaction score
103
Karem TR75 JHL
Karem Aircraft displayed models of both its latest TR75 Optimum Speed Tilt Rotor (OSTR) concept for the US Army's Joint Heavy Lift requirement, and the TR53 AeroTrain civil tiltrotor, which would be based on the 71%-scale demonstrator proposed for the JHL programme.

Karem TR53 AeroTrain

JHL is now being merged with the US Air Force's AJACS C-130 replacement, and there are no longer plans to build technology demonstrators, but Predator UAV designer Abe Karem says he is privately funding construction of a prototype rotor and drive system for the 120-seat AeroTrain.
Source: AVIATION WEEK - Ares A Defense Technology Blog - Ideas on Show at Helo Forum in Montreal (Posted by Graham Warwick at 5/2/2008 11:48 AM CDT)
 

hesham

CLEARANCE: Above Top Secret
Joined
May 26, 2006
Messages
23,872
Reaction score
922
Hi,

http://www.cbo.gov/ftpdocs/88xx/doc8865/11-30-Helicopters.pdf
 

Attachments

fightingirish

CLEARANCE: Top Secret
Senior Member
Joined
Jun 3, 2006
Messages
2,133
Reaction score
103
Mini - C-17 versus Mega V-22;) ;D
Funding realities have forced the U.S. Army and Air Force to merge their separate pursuits of a future heavylift tactical transport. The Army Joint Heavy Lift (JHL) and Air Force Advanced Joint Air Combat System (AJACS) - neither of which really were joint - have become the Joint Future Theater Lift (JFTL).

The two services are drawing up a joint requirement and plan an analysis of alternatives that will look at aircraft options ranging from 0ft VTOL (the Army's preference) to 1,500ft STOL (the Air Force's). They hope to complete the AOA by late 2009. While the desire is to find a single aircraft than can meet both services' needs, a senior Army officer says the effort could still result in two different aircraft - or two versions of the same aircraft.

Enter Boeing, which at the AHS International forum in Montreal last week showed its Joint Common Air-Lift System concept. JCALS has a common fuselage and avionics, but different wings and propulsion systems. The Air Force version looks like a mini-C-17 while the Army version looks like a bigger V-22 tiltrotor. Is such a thing possible? That will depend on whether JFTL can survive the Pentagon budget battles. Check out the story online on AWIN and in Tuesday's Aerospace Daily.
Boeing's JCALS: you want that with fixed wings or tilt rotors?



Source: Ares - A Defense Technology Blog
 

flateric

CLEARANCE: Above Top Secret
Staff member
Top Contributor
Senior Member
Joined
Apr 2, 2006
Messages
8,781
Reaction score
204
Wednesday, April 9, 2008
"The Program Formerly Known as Joint Heavy Lift"
Say farewell to Joint Heavy Lift, the U.S. Army's aspiration to a multi-service, next-generation heavy-lifter. The program, spearheaded by the Army Aviation Technology Directorate, seems to have been overcome by requirements creep and inter-service rivalry. It was aimed at satisfying intra-theater lift requirements of the Army's Future Combat Systems. But that program's target payload ballooned, most recently from 20 to 30 tons. That, in turn, dictated an aircraft on the order of a Lockheed Martin C-130, which tread dangerously close U.S. Air Force turf. Today, briefing at the annual gathering of the Army Aviation Assn of America outside Washington, a top Army requirements official referred to "the program formerly known as Joint Heavy Lift." The new name, said Col. Rick Stockhausen, director of concepts and requirements at the Aviation Warfighting Center, is Joint Future Theater Lift. It is a concept, he added, and is looking at lifting a 28-ton payload

http://www.aviationtoday.com/rw/military/utility/20952.html

Interesting, how NG will try to fit tilt rotors to this? =) Hmm, lift fans may be...But Lockheed AMC-X/AJACS surely out of the fixed wing/tiltrotor conversion game.
 

Attachments

LowObservable

CLEARANCE: Top Secret
Senior Member
Joined
Oct 18, 2006
Messages
2,169
Reaction score
24
Just when you thought that there was nothing left to be done to a Herk...
 

flateric

CLEARANCE: Above Top Secret
Staff member
Top Contributor
Senior Member
Joined
Apr 2, 2006
Messages
8,781
Reaction score
204
This is Herk-based AMC-X derivative *prototype* using JSF-tech shaft-driven lift-fans.
 

sferrin

CLEARANCE: Above Top Secret
Senior Member
Joined
Jun 3, 2011
Messages
11,937
Reaction score
277
You gotta wonder why they'd put a wing designed for stealth on a Hercules (and one with large high bypass engine fans visible at that).
 

yasotay

CLEARANCE: Top Secret
Senior Member
Joined
Oct 19, 2006
Messages
1,972
Reaction score
72
USAF and others rail at the huge expense of a C-130 sized tilt-rotor then shows the Army a B-2 like stealthy transports. One has to wonder at the cost of that sort of airframe and why a rotorcraft is too expensive.

By no means am I an engineer, but one has to wonder at what will happen to the airflow into the aft mounted engines of the Lockheed concept posted above. I also wonder about foreign object damage and the CG limitations of the concept. I have to giggle at the downwash impact of the design as well when folks question a tilt-rotor downwash for an aircraft of this size and weight.
 

TinWing

CLEARANCE: Top Secret
Senior Member
Joined
Jan 3, 2006
Messages
888
Reaction score
9
yasotay said:
USAF and others rail at the huge expense of a C-130 sized tilt-rotor then shows the Army a B-2 like stealthy transports. One has to wonder at the cost of that sort of airframe and why a rotorcraft is too expensive.
Considers the costs associated with the V-22, then multiply those costs by a factor of 3 or 4 for a "C-130 sized tilt-rotor." The term "tilt-rotor" should be considered to be an obscenity in defense aerospace after the long, painful development of the V-22.

On the other hand, a low observability, multi-role STOL transport remains a tantalizing prospect, assuming that JSF technology transfer results in relative affordable development, production, and maintenance costs.
 
Top