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Open letter to Sikorsky
Quote from ~ Flight International, Feb 8-14, 2005
"Sikorsky has decided not to bid for the US Army's Armed Reconnaissance Helicopter and the Light Utility Helicopter programmes and is instead looking further ahead. "With the business growing, we have the luxury to look at what is the next big thing we do that is not 'me too'" says Pino [senior vice-president marketing and commercial programs]. "By the end of the year we will be better able to tell what the next breakthrough might be."" ___________________ Dear Sikorsky, A long sixty years after the inception of the helicopter, you appear to be acknowledging the need for a second-generation craft. Perhaps, you will take this opportunity to finally put rotorcraft research and development back on the correct track; the track where it was, before being pushed off to the side by the tail rotor. The German Side-by-side Focke Fw 61 and the Intermeshing Flettner Fl 282 were the world's first viable rotorcraft. Both of these craft had latterly displaced twin main-rotor configurations. Unfortunately, meaningful pursuit of the lateral configured helicopters was never done in North America. I humbly suggest that the preeminent second-generation large rotorcraft will have an Interleaved configuration [http://www.unicopter.com/1121.html ], with; ~ extremely rigid rotors, ~ active blade twist, with reverse velocity utilization, ~ low tip speed, plus large chord, ~ pusher propellers or fans, ~ no wings (no compound design). This configuration appears to offer a number of significant advantages and few disadvantages, when compared to the contending tilt rotor configuration. Yours provocatively; Dave Jackson |
#2
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Interesting. They're right in that both the ARH and LUH are supposed
to be quickie buys of off-the-shelf aircraft. (We'll see about that.) Without a small product in-house and ready to go, they were out of the game. Sikorsky has done some studies of telescoping tilt rotors -- the blades slide out to maximum rotor disk diameter for hovering, back in for cruise. I believe they've also looked at folding tilt rotors that jacknife back in cruising flight. Both a long ways out, I think. Hopefully, there is something viable in their design studies. The X-Wing came to zilch when the government cut off the money. Trouble is, NASA is no longer funding rotorcraft research, and the military services still go off in separate directions. HW |
#3
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I wonder if the "next big thing" is a bigger push into UAVs? Sikorskys
UCAR proposal used Kamans intermeshing rotor system and claimed some remarkable advancements in speed. Of course the Army pulled the plug on DARPAs UCAR program, but maybe Sikorskys already interested in intermeshing rotor concepts. I hope you get a response from Sikorsky. But why limit your proposal to one company? There are a lot of small companies looking for break through technologies for advanced UAVs. Have fun, CTR |
#4
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Dave your obvious hatred for the tail rotor makes me believe that you have
been injured by one at one time or another. As the editor of Experimental Helo magazine, I get exposed to alternative methods such as you suggest. No one has demonstrated that they can be economically produced. The addition of another complete rotor with the accompanying transmission and control systems add both construction, maintenance costs. The primary savings available would be in the fuel saved over the tail rotor machine. Would it be enough? Simple issues such as tracking and balancing blades gets more complex with the co-axial and intermeshed rotor systems. I would expect that both of these modes of propulsion would have more modes of vibrations excitation that would have to be dealt with. I'm having enough trouble getting 2/rev vibrations under control with a simple two bladed, tail rotor machine. I can't imagine the difficulties that I would encounter with the machine that you describe. Have you built and de-bugged your design yet? Concepts are one thing, operational ships are another. History has said that all of the major helicopter mfrs. have visited the idea of getting rid of the tail rotor and gave it up for a myriad of reasons. While technology has relieved some of those reasons, the physics remain. With all that said there is one co-axial helicopter that has been test flown that is being prepped for the homebuilt market: The Ezycopter. I know of no one flying the intermeshing rotors in a ship that competes price wise with an equivalent performing tail rotor ship. It just doesn't seem possible to make a ship with the additional main rotor system and transmission system and control system that can compete with the standard tail rotor ship. If I'm proved wrong, a bottle of single malt scotch whiskey is yours. -- Stuart Fields Experimental Helo magazine P. O. Box 1585 Inyokern, CA 93527 (760) 377-4478 (760) 408-9747 general and layout cell (760) 608-1299 technical and advertising cell www.vkss.com www.experimentalhelo.com "Dave Jackson" wrote in message news:XNO0e.778773$8l.282021@pd7tw1no... Quote from ~ Flight International, Feb 8-14, 2005 "Sikorsky has decided not to bid for the US Army's Armed Reconnaissance Helicopter and the Light Utility Helicopter programmes and is instead looking further ahead. "With the business growing, we have the luxury to look at what is the next big thing we do that is not 'me too'" says Pino [senior vice-president marketing and commercial programs]. "By the end of the year we will be better able to tell what the next breakthrough might be."" ___________________ Dear Sikorsky, A long sixty years after the inception of the helicopter, you appear to be acknowledging the need for a second-generation craft. Perhaps, you will take this opportunity to finally put rotorcraft research and development back on the correct track; the track where it was, before being pushed off to the side by the tail rotor. The German Side-by-side Focke Fw 61 and the Intermeshing Flettner Fl 282 were the world's first viable rotorcraft. Both of these craft had latterly displaced twin main-rotor configurations. Unfortunately, meaningful pursuit of the lateral configured helicopters was never done in North America. I humbly suggest that the preeminent second-generation large rotorcraft will have an Interleaved configuration [http://www.unicopter.com/1121.html ], with; ~ extremely rigid rotors, ~ active blade twist, with reverse velocity utilization, ~ low tip speed, plus large chord, ~ pusher propellers or fans, ~ no wings (no compound design). This configuration appears to offer a number of significant advantages and few disadvantages, when compared to the contending tilt rotor configuration. Yours provocatively; Dave Jackson |
#5
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Hi Stu,
"Dave your obvious hatred for the tail rotor makes me believe that you have been injured by one at one time or another." No. It was the rotorcraft industry that was injured when Igor got too eager to get something off the ground. "No one has demonstrated that they [twin lateral main rotors] can be economically produced." Henry Ford proved the economies of large-scale production. To design and produce a few 'Ford type' cars in a local machine shop would cost more than a half-million dollars per car. Unfortunately, in rotorcraft there is one civilian helicopter for every half-million people. "If you build a better mousetrap, the world will beat a path to your door." "It just doesn't seem possible to make a ship with the additional main rotor system and transmission system and control system that can compete with the standard tail rotor ship." I agree. For today's homebuilder; the price, the building, the displaying, and the pride of flying a craft with limited stability, is the pleasure and it is the market. The gyrocopter is epitome of this. However, for mass acceptance, the single-rotor equivalent of the 'unicycle' must be morphed into the twin-rotor equivalent of the lower cost 'bicycle'. How old is the Scotch whiskey? Dave Not coincidentally |
#6
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Dave: I just drove down hiway 395 where there were a bunch of "mass
accepted" automobiles and drivers that I wish were in drivers ed a bunch longer. I think that if everyone of those drivers were in an intermeshing helicopter headed toward the ski area, we would have aluminum showeres to end all showers. If the death of the tail rotor leads to providing these guys with a helicopter, I will vote to keep the tail rotor. BTW I don't seem to have much trouble flying the tail rotor. I would have trouble in an auto rotation in a ship where the controls need to be reversed. I think 10 yr old scotch ought to do it. Even older, if we share it. Stu "Dave Jackson" wrote in message news:S5%0e.785167$Xk.347264@pd7tw3no... Hi Stu, "Dave your obvious hatred for the tail rotor makes me believe that you have been injured by one at one time or another." No. It was the rotorcraft industry that was injured when Igor got too eager to get something off the ground. "No one has demonstrated that they [twin lateral main rotors] can be economically produced." Henry Ford proved the economies of large-scale production. To design and produce a few 'Ford type' cars in a local machine shop would cost more than a half-million dollars per car. Unfortunately, in rotorcraft there is one civilian helicopter for every half-million people. "If you build a better mousetrap, the world will beat a path to your door." "It just doesn't seem possible to make a ship with the additional main rotor system and transmission system and control system that can compete with the standard tail rotor ship." I agree. For today's homebuilder; the price, the building, the displaying, and the pride of flying a craft with limited stability, is the pleasure and it is the market. The gyrocopter is epitome of this. However, for mass acceptance, the single-rotor equivalent of the 'unicycle' must be morphed into the twin-rotor equivalent of the lower cost 'bicycle'. How old is the Scotch whiskey? Dave Not coincidentally |
#7
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On 2005-03-25 02:08:39 -0500, "Dave Jackson" said:
A long sixty years after the inception of the helicopter, you appear to be acknowledging the need for a second-generation craft. Sikorsky has built something like thirty-odd distinct types of helicopter and experimental rotorcraft. Sikorsky's second-generation craft was arguably the S-55 (H-19). You claim a speed advantage for your design. When you've flown something faster than the S-69 ABC, come back to the group and tell us how inept they are at Sikorsky and how great you are. Otherwise, you just sound like an empty windbag. The German Side-by-side Focke Fw 61 and the Intermeshing Flettner Fl 282 were the world's first viable rotorcraft. There was this Spanish cat named Juan de la Cierva... ever hear of him? He's in these things called books... Both of these craft had latterly displaced twin main-rotor configurations. And neither could match the performance of the initial Sikorsky helicopters. Or many others. It's also worth noting that Igor Sikorsky and Bill Hunt & Michael Buivid (his engineer & fabricator) considered, and even flew, many, many alternatives to what is now the common penny-farthing arrangement of main and tail rotor. Sikorsky, Bell, Hiller, Robinson... what a bunch of losers... Unfortunately, meaningful pursuit of the lateral configured helicopters was never done in North America. Yeah, Kaman is actually an Ethiopian concern under deep cover. This configuration appears to offer a number of significant advantages and few disadvantages, when compared to the contending tilt rotor configuration. For one thing, it's only a paper design that doesn't have to fly... heck of an advantage... cheers -=K=- Rule #1: Don't hit anything big. |
#8
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Excerpt from initial posting;
A long sixty years after the inception of the helicopter, you [Sikorsky] appear to be acknowledging the need for a second-generation craft. Kevin O'Brian's replies; Sikorsky has built something like thirty-odd distinct types of helicopter and experimental rotorcraft. Statement of Roger Krone, Senior Vice President Boeing Army Systems; "The Chinook was developed in the late 1950s, less than a decade after the B-52 bomber entered service. Since then, two follow-on bombers have been fielded, but no new heavy-lift helicopter." Meaningful advancements come about through revolutionary change not evolutionary change. Bell is perusing the tilt-rotor configuration. What's new at Sikorsky? _______________________ You claim a speed advantage for your design. When you've flown something faster than the S-69 ABC, come back to the group and tell us how inept they are at Sikorsky and how great you are. Otherwise, you just sound like an empty windbag. Reports on the S-69 ABC [http://www.UniCopter.com/0891.html] suggest that this craft could have flown even faster, if the lateral vibratory dysimitry had been reduced by using 4-blade rotors. But, I'm probably 'windbagging' you with information that you must already know. ______________________ The German Side-by-side Focke Fw 61 and the Intermeshing Flettner Fl 282 were the world's first viable rotorcraft. There was this Spanish cat named Juan de la Cierva... ever hear of him? He's in these things called books... You're right, I'm wrong. The word 'rotorcraft' should have read 'helicopters'. ______________________ Both of these craft [Focke Fw 61 and the Flettner Fl 282] had latterly displaced twin main-rotor configurations. And neither could match the performance of the initial Sikorsky helicopters. Interesting comment, particularly when one considers that they both were built before the Sikorsky R-4B. In actual fact, the Flettner surpassed the Sikorsky in most performance categories - including maximum forward speed . But again, I'm probably 'windbagging' you with information that you already know. ______________ Unfortunately, meaningful pursuit of the lateral configured helicopters was never done in North America. Yeah, Kaman is actually an Ethiopian concern under deep cover. The phrase used was, 'meaningful persuit'. Charles Kaman left United Technologies with only a few thousand dollars in his bank account, after being told that they did not need two Chief Engineers. It appears that he took the intermeshing helicopter into a niche market because he could not compete head-to-head with his large former employer. Kellett was on the right track, when he tried to raise one million dollars to develop a rigid 3-blade intermeshing rotor. Unfortunately, the death of his test pilot appears to have been the demise of Kellett's aspirations. _____________ Rule #1: Don't hit anything big. Rule #2: 'Biggest' ain't necessarily 'Best' cheers Dave |
#9
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Dave Jackson wrote:
Excerpt from initial posting; A long sixty years after the inception of the helicopter, you [Sikorsky] appear to be acknowledging the need for a second-generation craft. Kevin O'Brian's replies; Sikorsky has built something like thirty-odd distinct types of helicopter and experimental rotorcraft. Statement of Roger Krone, Senior Vice President Boeing Army Systems; "The Chinook was developed in the late 1950s, less than a decade after the B-52 bomber entered service. Since then, two follow-on bombers have been fielded, but no new heavy-lift helicopter." Dave, I believe you many of your arguments have sound technical merit, but comparing heavy lift helicopter development to US bombers is not quite fair. Logistics helicopter to bomber development, or heavy-lift helicopter to heavy bomber, yes. I would disagree that the B-52 has had two successful follow-ons for heavy bombers, I would say just one: the B-1, which is a succussful heavy bomber. The B-2 is too revolutionary, specialized, expensive and produced in too few numbers- it is an apples to oranges comparison. It is a successful weapons system because warfare has changed- accurate munitions instead of carpet bombing. Meanwhile the B-52 continues to be successful at the heavy bomber mission. Similarly, the Chinook is still successful, and so is the H-53. The Boeing guy didn't mention the 53, even if admittedly he did state "new" heavy-lift helicopter. But there you have two and only two major types of aircraft that are still successful in each mission (heavy bomber and heavy lift helo). If you want to compare bombers, include the B-2 but also the B-58 and B-70, A-5, A-6, F-111, but on the helicopter side also include H-46, H-1, H-3, H-53, H-60, S-92, and now the rotary wing side doesn't look quite so stagnant. Revolutionary no, evolutionary yes. Food for thought anyway, I thought all of your remarks were interesting. |
#10
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On 2005-03-31 17:09:37 -0500, "Dave Jackson" said:
One shouldn't feed the trolls, but... "The Chinook was developed in the late 1950s, less than a decade after the B-52 bomber entered service. Since then, two follow-on bombers have been fielded, but no new heavy-lift helicopter." In the first place, he was mistaken. Two other, later developed, US military heavy-lift helicopters include the CH-53 used by the naval and air forces, and the S-64/CH-54 Tarhe. The Tarhe was retired from military use when continued improvement in the Chinook allowed the military to standardise on a single airframe. By the way, Erickson has resurrected the S-64 after acquiring the TC from Sikorsky and has four new airframes under construction. Then there's the KMAX but you seem to have some problem recognizing that the people that built that machine were serious. When the US cannot lift something with a Hook these days, they hire an Mi-26 like everybody else. Certainly the Mi-6, -10, and -26 qualify as heavy lift helicopters. All of which use rotorheads and controls that would be terribly familiar to anyone familiar with pre-Black Hawk Sikorsky practice. Meaningful advancements come about through revolutionary change not evolutionary change. Empty platitude. You are not allowed to spew empty platitudes until you actually become a legend, which would require you to do something, not just snipe at those who are. Bell is perusing the tilt-rotor configuration. What's new at Sikorsky? I think you mean "pursuing?" Well, let's see, at Sikorsky: 1. Continued sales and improvementg of the S-70. 2. Two new versions of the S-76, including a new purpose-built P&W motor for the S-76D. 3. Adapting the aerodynamic lessons learnt from the Comanche program to enhance the performance downline. 4. Integrating the Schweizer operation, which gives Sikorsky: a. a very successful training helicopter b. a leading VTOL UAV program c. "Hawk Works" -- a rapid prototyping shop that can't be done in the management/labor environment of the big winged S, but can be done in the boonies at Horseheads. 5. An uphill fight to sell the S-92 into US military contracts written specificially for the EH101 for political reasons. I said: When you've flown something faster than the S-69 ABC, come back to the group and tell us how inept they are at Sikorsky and how great you are. And you said: Reports on the S-69 ABC [http://www.UniCopter.com/0891.html] suggest that this craft could have flown even faster, Like which of your aircraft Dave? Oh, haven't actually designed, or built, or flown anything, have you? Accomplishment first, boasting later, if you please. In actual fact, the Flettner surpassed the Sikorsky in most performance categories - including maximum forward speed . Has it ever occured to you that maximum forward speed is not what actual helicopter (or airplane) buyers want? You could point out that a TBM700 for instance, goes twice as fast and almost three times as high as a Cessna Caravan, with a very similar powerplant. So why do buyers buy nine Caravans for every TBM? A Corvette goes much faster than a Ford pickup truck. Nonetheless, many ignorant buyers, some of whom even already own a Corvette, buy Ford trucks every year. The phrase used was, 'meaningful persuit'. I don't think operating a company that has had a good run for decades and which shipped thousands of helicopters is exactly meaningless -- especially when compared to the record of aircraft built and shipped that you are standing on when you slur these people. It appears that he took the intermeshing helicopter into a niche market because he could not compete head-to-head with his large former employer. So very queer that the market he wound up in -- shipboard operations -- was the same one that the Russian counterpart wound up in. Could it be that the complex intermeshing or coax systems are worth tolerating when compactness is of overwhelming importance. Once you could fold up a "real" helicopter, the jig was up for these types. Kaman's in trouble now not because of their own programs, but because MD Helicopters stiffed them on paying for airframes that they built for that firm (formerly part of Boeing, McDonnell Douglas, and Hughes, and now back in the Boeing camp again, at least as long as they are still in running for the two Army contracts). When you actually build real stuff you have to then face the challenge of getting real people to pay real money for it. As far as the impossibility of competing with former employers, how do you explain Frank Robinson? He also worked for a large helicopter company (a few of them in fact). And last year about 700 civil helicopters shipped from US plants, and over 600 of them came from his. Yep, you just can't compete with that big established cartel. One reason Frank pushes people so hard and is such a bear to work for, is that he KNOWS that it can be done and that for all the people looking at a drawing board and saying, "no way, you can't compete with Robinson in the piston market," there just might be one who knows that it can be done, too. The only way you make a sale is by having what the customer wants -- and in the helicopter world, we are talking about goods so expensive that it is usually a matter of need, a dispassionate choice of a business tool. Kellett was on the right track, when he tried to raise one million dollars The story of vertical flight is of necessity a story of many dead ends. Imaging conspiracies with which The Man kept the brotherhood down is not going to get anything accomplished. If you want to revolutionize the industry you could do what Kaman and Robinson and even Burt Rutan did -- get a basic engineering education, start at entry level in the industry and proceed to jobs of increasing responsibility. But you don't get to start as Chief Engineer and CEO, unless you want your ideas to die stillborn on your drawing board. I suppose that actually trying to build something, and seeing how damned hard it is, would threaten your self-image as a genius whose brilliance has condemned him to obscurity. No, your lack of actual output has condemned you to obscurity. And it's just that damned simple. Even Kellett is in the books, and for what he flew more than for what he didn't. cheers -=K=- Rule #1: Don't hit anything big. |
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