Bell V-280 Vs. Sikorsky-Boeing SB>1: Who Will Win Future Vertical Lift? He honed his language skills as a US Army linguist (Polish and German) before diving into editing tech publications back when the web was just getting under way. The rigid rotors provided high control power. Despite all the differences, the fundamental selling points for both designs are speed and range. The cockpit will seat two pilots side-by-side, and the cabin behind them will fit six combat-equipped soldiers. Bell V-280 Valor Joint Multi-Role Demonstrator (CGI graphic). Updated 4:55 pm to clarify Richard Aboulafias remarks on Army preferences. This seemed to work out fine in the initial hover tests. There are two main ways to overcome this inherent speed limit of helicopters: tilt-rotors, like Bells V-280, or compound helicopters, like the Boeing-Sikorsky SB>1. Sikorsky-Boeing SB>1 Defiant. The counter-rotating blades are engineered toreduce high-speed vibrations, steady the aircraft and best optimize massive amounts of thrust coming from a pusher prop mechanism in the rear of the aircraft. If only we devoted as much time, money and resources to fixing the planet as we do to making systems to kill one another we might save the planet. This promised to be much lighter than the armor then available and more effective at defeating ballistic threats. advance ratios, the potential for greater tion for applications of HHC to a counter-interharmonic coupling exists, rotating aircraft at very high speed in the 12000 ib range of gross weight. propellers,a significant difference in design from helicopters of the past six decades. In a separate project, Sikorsky is working with Boeing on an X2-based helicopter called the SB-1 Defiant in a precursor program to the the Army-led Future Vertical Lift initiative, which aims to find a next-generation medium-lift helicopter for use across all the military branches. The V-280 has the same size rotors as the V-22 but weighs half as much, Gehler said, giving it 50 percent more control power than a V-22 at low speeds, superior to the present-day Black Hawk and Apache. Primarily among these was the use of separate engines for rotor power and auxiliary propulsion. Join our Space Forums to keep talking space on the latest missions, night sky and more! The six-passenger bird will be developed for the military and will. Photo courtesy Sikorsky and Boeing. These will be effective at getting injured people out of remote areas quicker and also, the ability to possibly commute further without having to go through a transit hub. The Washington Times Contra-rotating coaxial rotors cancels out the retreating blade stall limit of helicopters by providing a balancing lift with the opposite direction. With faster speeds, you get less lift capacity unless you want to pay more. Other American helicopter pioneers like Larry Bell, Stanley Hiller, and Frank Piasecki subsequently employed this convention. The basic airframes there, the cockpit doors are installed, the weapons bay doors are installed, the landing gear is installed and serviced, [and] many of the electrical and hydraulic subsystems are fully installed and going through their acceptance test procedures., In the photo above, a few details stand out. When Black Marxist Angela Davis found out her ancestors owned slaves. Elevators were included in the tail. Built in Connecticut, the Sikorsky CH-53K is the latest in the Companys proud helicopter legacy. Mike Glenn can be reached at mglenn@washingtontimes.com. Sikorsky, a Lockheed Martin company, filed a formal protest this week asking the U.S. Government Accountability Office (GAO) to review the Armys decision for what the service has called the Future Long-Range Assault Aircraft (FLRAA). In phase 1 of the contract manufacturing techniques, including methods for cutting, joining, forming and finishing the material, were evaluated. The downside of a tilt-rotor is the mechanical complexity and weight of the mechanisms needed to do the tilting as well as the need to switch modes in flight. To replace the Apache gunships, an aircraft needs to fly low and slow over the battlefield, ducking behind cover when enemy anti-aircraft units appear, then popping up again to fire guns and missiles. We are flying before buying.. Sikorsky's engineering studies showed that, to get a single-main-rotor helicopter to reach the speeds the Army wants, you need to squeeze every drop of power from the engine and streamline the. Built to thrive on the modern battlefield, including shipboard operations, the CH-53K aircraft is designed to be intelligent, reliable, low maintenance and survivable in the most austere and remote forward operating bases. Sikorsky, a Lockheed Martin company (NYSE:LMT), in Stratford, Connecticut, and Boeing Defense, Space & Security (NYSE:BA) in Berkeley, Missouri, are introducing the SB>1 DEFIANT helicopter designed to fly with advanced agility and maneuverability at twice the speed and range of current conventional helicopters. is their ability to take off and land vertically.However, compared with fixed-wing aircraft, they are slow. Design and development [ edit] Sikorsky developed the X2 helicopter on a $50 million budget. They were refined in the S-97 Raider and now the SB>1. The following reference has great detail of information on the full ABC program, including manufacturing technology used, aircraft description, and ground and flight test results: American Helicopter Society paper The ABC Rotor A Historical Perspective, Robert K. Burgess. The 40 foot diameter rotor that was wind tunnel tested in 1970 was sized for a 14,500 lb gross weight, 230 knot aircraft which was felt at the time to be a size with a wide range of mission potential. This design delivers that, plus incredible speed. In a more developed design, a single propulsion system would power both the rotor and an auxiliary propulsion propeller or ducted fan. Theyve learned a lot since they built the V-22, said V-280 program manager Chris Gehler, and theyve radically upgraded the low-speed handling qualities, he told reporters in Amarillo. Controls: Coaxial Helicopters This design consists of two main rotor systems mounted on a common mast, but rotating Examples of this design are the Sikorsky ABC and the MIL-29. The Kiowa, which has been the Army's primary scout helicopter since the mid-1990s, by contrast has a cruising speed in the area of 120 mph. Meanwhile, over at Bell, their FARA candidateboth companies refer to the aircraft they are working on as a competitive prototypeis the 360 Invictus, which in March was reported to be 87-percent finished. He could be considered the most important person in the helicopter design. The spar tubes were then hot formed into an elliptical shape, while twisted, in ceramic hot-forming dies. Design studies showed that four-bladed rotors would dramatically reduce the rotors vibratory characteristics. Copyright 2023 The Washington Times, LLC. Timeline of the Sikorsky Aircraft Company. Compared to conventional helicopters, the counter-rotating coaxial setup and pusher propeller offer a significant speed increase, a 60 percent . Naval Air Test Center Technical Report, RW-37R-79, Final report, Advanced Helicopter Rotor Systems, Initial Navy Evaluation of the XH-59A Advancing Blade Concept (ABC) Demonstrator Aircraft, LT. T.L.MacDonald, USN; MAJ M.S.Blair, USMC; and S. Kolwey, January 17, 1980. The XH-59A was a unique design built strictly as a test vehicle for the advancing blade concept rotor system. The ' Sikorsky Aircraft is currently added mechanical challenge of the two I Auxiliary propulsion flights were conducted from April 1978 to January 1981. This was phased out at speeds from 40 to 80 knots and yaw control was provided by rudders. Photo: Sikorsky Aircraft Corp. To paraphrase helicopter pioneer Igor Sikorsky: If you're in trouble . High-power engines are necessary to drive rotating blades, which . To date, the Sikorsky X2 has been developed into two main helicopters: Boeing-Sikorsky SB-1 Defiant and Sikorsky S-97 Raider. There were many coaxial helicopter developments during and after World War II. Its twin rotor system will minimize downwash as you get on and off, and Sikorsky also claims a "dramatically reduced acoustic signature." Some obvious design differences present themselves between the two aircraft prototypes: Bells aircraft employs a single main rotor up top, and a tandem cockpit, meaning the two pilots sit with one person in front of the other, as opposed to side-by-side. Whats visible is a simulated version of a system called the modular effects launcher, which someday could carry missiles, rockets, or other kinetic objects, like drones or other sensors. The empennage was an inverted V to keep it under the rotor and minimize aircraft size. The turret thats installed on the aircraft is the real deal flight-worthy turret, Germanowski says, with the actuation motors, and the motor controller unit, and all of the electronics that allow us to swivel the gun in azimuth, and pitch the gun in elevation., [Related: Sikorskys fancy new helicopter completed its longest flight yet]. At higher speeds, moreover, helicopters run into a problem called retreating blade stall. said Grant. The CH-53K continues to successfully execute key performance, test, and production milestones. The test envelope was expanded to level flight at 156 knots, dive speeds to 186 knots, and altitudes to 14,000 feet. This flight marks a key milestone for the Sikorsky-Boeing team, and is the culmination of significant design, simulation and test activity to further demonstrate the capability of the X2 Technology. On top of the helicopter is another component thats 3D-printed, as a stand-in for what will be the hubs for the top rotors and the gearbox. . Click You dont want to wait for your rotors to tilt from vertical to horizontal flight mode like a V-22 or V-280, Van Buiten argued. The Containerized Flight Training Device (CFTD) is a full-mission flight simulator that will allow flight crews to train on the full scope of Marine Corps heavy lift missions, including external lift operations, and executing degraded visual environment take-offs and landings. As a result, the control system was designed with a very low gain to prevent the controls from being too sensitive. "Weare diligently pursuing this as a research project. Some balance is needed in order to keep the machine stable--usually either another, counter-rotating rotor or a small vertically-mounted tail rotor. Presented at the 37th AHS Annual Forum, New Orleans, LA, May, 1981. These useful machines handle everything from tourism to search and rescue. Since you can only generate lift by moving the whole aircraft forward, you need a long runway to take off and must keep moving forward while in flight. Lockheed Martin delivered the first CH-53K training device to the U.S. Navy on April 14, 2020. When you purchase through links on our site, we may earn an affiliate commission. Sikorsky has released new shots of its Raider X prototype aircraft sporting modular weapon launchers loaded with Hellfire missiles and a 20mm main gun. Eric Adams Eric. What does an independent expert think? Similar to the X2 prototype, the Sikorsky S-97 Raider helicopter will have twin coaxial counter-rotating main rotors and a pusher propeller for cruise at 220 knots. Pino said of the X2 TechnologyDemonstrator at Heli-Expo 2008, the main U.S. helicopter convention. The rotor design had to be more similar to that of a propeller than that of then current helicopter rotors. But all of these were two conventional rotors mounted in a coaxial counter-rotational configuration. While its unclear when the Army will make a decision as to which aircraft it wants to go with for the FARA program, the FLRAA competition is further along. It is similar to a tandem rotor system when in helicopter mode. But Sikorsky also created an alternative to the compound helicopter the Advancing Blade Concept, or ABC. Counter-rotating: Hub Type: Main Rotor . Melissa Chadwick Two aircraft were fabricated. Update: In an email, an Army spokesperson says the service plans to make a decision for one FARA aircraft in fiscal year 2025, which for the US government begins Oct. 1, 2024. Each control input provided the desired control response with little extraneous response in the other axes. Spice up your small talk with the latest tech news, products and reviews. The helicopter has a small rotor at the end of a tail boom (Sikorsky) Or a fan instead of the propellor (Fenestron Aerospatiale) Or a jet thrust output (Cierva W.9, NOTAR) 4. Sikorsky hopes the X2 will fly nearly twice as fast as today's helicopters. An extensive flight test program of about 170 flight hours was accomplished through 1981. Born in Kiev, Ukraine, in 1889 to a family of physicians, Igor Sikorsky actually built his first helicopter at the age of 12. Though not much is known about the aircraft, FAA documents show the S-100 has two engines, 14 seats and a lift-weight class of 20,000 kg or over. The same design approach was also considered for a larger AAPC, Aerial Armored Personnel Carrier, carrying twelve troops within the armored fuselage. Media Contact Learn More. I recently coordinated engineering efforts for the Future . Here's What You Need To Remember:The new aircraft will employ several measures designed to make it quieter, including, most notably, a counter-rotating rotor that muffles the sound of the first. We have invested in developing and demonstrating hypersonic technology for over 30 years. A maximum level flight speed of 240 knots was achieved, making this the first rotary wing aircraft to achieve this speed without the use of an auxiliary wing, thus proving the basic advancing blade concept. The CH-53K helicopter has been designed and built to the exacting standards of the U.S. Marine Corps (USMC) and will serve as its critical land and sea based logistics connector. In high speed flight the XH-59A handled as though it were a fixed wing aircraft. Last month, the Army saw its final class of eight aviators complete Kiowa flight training at Fort Rucker, Alabama. When the job is hot, high, dirty or dangerous, the K-MAX is ready performing multiple missions. One of the concerns with the coaxial rotor arrangement was how to provide aircraft yaw control. This would be great for turbulant rescues, say at sea. Two images of Raider X in a hangar in West Palm Beach, Florida, shared recently by Sikorsky, reveal how the companys prototype is coming together. Will the military actually buy either design? 80 years ago, Russian-born inventor-engineer and pilot Igor Sikorsky made the first flight of his self-designed single-rotor helicopter, the VS-300. However, the direction chosen seems to depend on where the helicopter is designed and built. (Bells partner on the V-22, Boeing, switched sides on FVL). In September 2010, Sikorsky's similarly designed X2 technology demonstrator reached a speed of 250 knots (287 mph), a feat that the longtime rotorcraft maker at the time said "unofficially shattered the helicopter world speed record." The fastest Army helicopter in widespread service, the CH-47F Chinook, maxes out at about 170 knots, which is 195 miles per hour, and has an effective reach (mission radius) of 200 nautical miles, or 230 statute miles. Terms of Use / Privacy Policy / Manage Newsletters, - Sikorsky Aircraft and Boeing have developed their next-generation compound helicopter, and flight testing is underway to determine if the aircraft is capable of entering the U.S. military fleet. : The Future Vertical Lift program aims to create revolutionary replacements for todays military helicopters. Oct 26, 1972 : Igor Sikorsky dies due a heart attack at the age of 83. Yaw control was achieved by using differential collective pitch in hover. The rotor system is typically of the fully-articulated design. A trade-off study was proposed on the question of three versus four-bladed rotors. Sikorsky hopes the X2 will fly. "Experimentalaircraft have minds of their own ? He writes occasionally, on topics from GPS to James Bond. Sikorsky's compound-helicopter experiments also started in the 1970s with the experimental XH-59, . On a tour of the Stratford plant on Wednesday, a Sikorsky executive called the HH-60W Jolly Green II the most advanced combat helicopter ever produced by Sikorsky, with a range of defensive. They will be coming soon I'd imagine fb. Lockheed Sikorsky-Boeings SB Defiant has taken flight more recently than Textron-Bells 280 Valor, however both appear to be showing early promise. 1939: Igor Ivanovitch Sikorsky built the helicopter VS-300 which flew in May 13, 1940. However, they each claim their aircraft is more agile a crucial consideration when landing troops in tight spaces or ducking behind hills and trees to hide from radar. The object protruding from the front is a 3D-printed simulated cannon. Igor Sikorskys predictions for air travel in general and for helicopters in particular have been largely realized or surpassed. Sikorsky's technology puts two main rotors on top of each other, rotating in opposite directions, which balances out the lift profile on either side and allows the craft to fly much faster - up. | Its an old joke with a kernel of aerodynamic truth. Our Multi-Domain Operations/Joint All-Domain Operations solutions provide a complete picture of the battlespace and empowers warfighters to quickly make decisions that drive action. ABC required the spar to be tapered in both diameter and wall thickness to be able to carry the high bending moments developed when the rotors lift moved off the rotor centerline. The XH-59A exhibited excellent handling qualities. Join PopSci+ to read sciences greatest stories. Heres how it works. Sikorskybuilt the X2 Technology Demonstrator in collaboration with subsidiary SchweizerAircraft, and funded the project entirely by itself. Nelson Hyde Chick - this will likely be used for more then just war. Primarily the advantages were compactness and the elimination of the tail rotor; no thought or capability of using advancing blade lift was considered in these designs. He also has a Masters Degree in Comparative Literature from Columbia University. S-70A-1 Desert Hawk; variant for Saudi Arabian military S-70A-1L Saudi Desert Hawk Medevac variant S-70A-5 Variant for Philippine Air Force S-70A-9 Part 1 of a narrative series illustrating how Americas armed forces might use technology to accomplish their most demanding missions. The conclusion was that the control system gains were too low to cover all flight modes. That required changing how the rotors flap, improving materials, and, above all, increasing the size of the rotors relative to the aircraft. That lets them take off and land vertically, fly sideways or backwards, and hover, but its not as fast or as fuel efficient in horizontal flight as an airplane. About the develemental phase when you already have a proven concept, insane. Sikorsky's helicopters featured a sophisticated design which outperformed other manufacturers. American Helicopter Society paper Fifty Years of Sikorsky High Speed Concepts, Arthur W. Linden. Missions Armed reconnaissance Length 37ft Width 16ft Rotor Diameter 34ft Speed 220k Expand Army funding came from the Army Materials and Mechanics Research Center in Watertown, Mass, which was responsible for much of the development of the dual-hardness armor. It's not an idle promise. It's also a more complex beast than a traditional single-rotor configuration. Sikorsky hopes that the sleek, speedy design of the S-97, unveiled Thursday, will win the favor of the US Army as a potential replacement for OH-58D Kiowa Warrior helicopter, an airframe whose history dates back to the Vietnam War era, and as an aerial platform for special operations units. Providing a balancing Lift with the coaxial rotor arrangement was how to provide aircraft yaw control achieved. 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