Je pense que les infos sur cette familles sont disséminés dans différents autres sujets.
Cette famille importante constitue une cheville ouvrière de l'USMC.
Un petit point sur le programme de modernisation de la version SUPER -E en version -K
Programme de 156 appareils.
Les -E sont actuellement très utilisés et malgré le recourt au cimetière de Davis Montan AFB pour cannibalisation, la période 2012-2015 va être difficile : pb d'approvisionnement en pièces détachées.
En outre au taux d'utilisation actuel, les premières cellules arriveront à bout de potentiel (6120 heures) en 2011 ... par paquet de 15 annuellement.
Le CH-53K atteindra les capacités opérationnelles initiale en 2014-2015.
Les specs du CH53K indiquent un transport de 13T à 110 NM, y compris dans des conditions HOT et HIGH.
Nouvelle motorisation GE38... je suis curieux, je vais aller gratter un peu de ce côté.
CH-53K: The U.S. Marines’ HLR Helicopter Program
12-Jan-2010 10:48 EST
The U.S. Marines have a problem. The CH-53E Super Stallion medium-heavy lift helicopters they rely upon to move troops, vehicles, and supplies off of their ships are wearing out. Fast. Yet the pace demanded by the Global War on Terror is relentless, and usage rates are 3 times normal. Attrition is taking its toll, and CH-53s are being recalled from “boneyard” storage at Davis-Monthan AFB in Tucson, AZ, in order to maintain fleet numbers in the face of recent losses and forced retirements. No flyable spare airframes are left, and by 2012-2015, replacements will be urgently needed.
Enter the Heavy Lift Replacement (HLR) program, also known as the CH-53X and given the formal designation CH-53K in April 2006. The 156-helicopter program will define the future of the US Marine Corps’ medium-heavy lift capabilities. To fulfill that goal, Sikorsky received $3.04 billion for System Development and Demonstration (SDD), to include 4 SDD aircraft, 1 ground test vehicle, and associated program management and test support. Initial Operational Capability isn’t set to happen until 2016, however, which risks a helicopter gap unless other measures are taken.
DID describes the CH-53K’s requirements, covers some of the potential improvements, and notes the treacherous political waters this program will need to survive, in order to wind up delivering US Marines the tools they’ll need to survive. The latest news involves a number of firsts and risk reduction efforts for the program, as it prepares for a critical year in 2010…
•The HLR Program Lifts Off
•The CH-53X / CH-53K [updated]
•HLR Program: Contracts, Events & Milestones [updated]
•Appendix A: Flying Between Scylla and Charbydis: Navigating The Political Shoals (April 2006)
•Appendix B: Interesting Ideas: The CH-53X Skycrane Concept
•Appendix C: Additional Readings & Sources
The HLR Program Lifts Off
On average, existing CH-53E aircraft are more than 15 years old, have over 3,000 flight hours under tough conditions, and are becoming more and more of a maintenance challenge with a 44:1 maintenance man-hours:flight hours ratio. Not to mention the resulting $20,000 per flight-hour cost ratio. According to Jane’s Defense Weekly, a 1999 analysis showed that the existing fleet has a service life of 6,120 flight hours, based on fatigue at the point where the tail folds. The USMC expects that the existing fleet will start to reach this point in 2011, at a rate of 15 aircraft per year.
The HLR program calls for 156 new-build helicopters derived from the CH-53E Super Stallion, with initial flight tests in 2010-2011 and initial operating capability in 2014-2015. US Navy PMA 261 is responsible for the program, and the program manager in February 2007 is Capt. Rick Muldoon.
In an August 2005 decision, the US Navy released an Acquisition Decision Memorandum (ADM) authorizing the HLR program to work toward Milestone B approval in Fiscal Year 2006. If granted by the Pentagon’s Defense Acquisition Board, Milestone B approval authorizes a program to move into the System Development and Demonstration (SDD) phase, the next step required under Department of Defense procurement procedures.
That go-ahead was eventually given. A Dec 22/05 decision by the under secretary of defense for Acquisition, Technology and Logistics gave the estimated $4.4 billion program the green light. In April 2006, a $3 billion April 2006 “Cost Plus Award Fee” contract for the System Development and Demonstration (SDD) phase was signed with Sikorsky. Sikorsky is currently conducting competitions to select suppliers, and is still making awards on that basis.
To date, industrial partners include:
•United Technologies: Program lead (Sikorsky); Integrated secondary power systems, Environmental control system, Computers for the fly-by-wire system, and Primary main and tail rotor actuators (Hamilton Sundstrand); Integrated fuel system, Aircraft hydraulics (Eaton);
•Aurora Flight Sciences: Fuselage – main rotor pylon;
•BAE Systems: Fly-by-wire integration, Cockpit seats and Cabin armor systems;
•Curtiss Wright, Inc.: Fly-by-wire components;
•EDO Corp.: Fuselage – tail rotor pylon & side sponsons;
•GE: GE38-1B engines;
•GKN Aerospace: Fuselage – aft transition;
•Goodrich: Tail drive system, Electrical power generation and distribution system;
•Northrop Grumman: Radar warning receiver;
•Spirit AeroSystems: Fuselage – Cockpit and cabin.
The CH-53X / CH-53K
The CH-53K’s maximum gross weight (MGW) will increase to 88,000 pounds, versus 73,500 pounds for the CH-53E. MGW with internal loads will be 74,000 pounds, compared to 69,750 pounds for the CH-53E. It is being designed to carry a cargo load of 27,000 pounds (13.5 tons) 110 nautical miles, operating at an altitude of 3,000 feet and an ambient temperature of 91.5 degrees Fahrenheit. This is nearly double the capacity of the current CH-53E Super Stallions, all in a helicopter that’s roughly the same size.
Those altitude and temperature qualifications matter, too, because “hot and high” conditions lower aircraft load carrying capabilities and combat radius – especially for helicopters. This reduced performance has recently been a factor during operations in Afghanistan and relief efforts in Pakistan, for instance, and has been a factor with earlier models of the C-130 Hercules as well. Figures for the CH-53K operating entirely around sea level and in cooler temperatures would be higher, but would not be double that of existing CH-53Es.
As an example of these variables at work, Sikorsky’s CH-53K brochure states that the improved CH-53K will have a maximum external load of 16.3t/ 36k lbs. Realistically, in an operation that carries an externally-slung load from sea level to a point 3,000 feet above sea level, with a total range there and back of 220 nautical miles/ 407 km, and 30 minute loiter at the landing zone, that same brochure gives its maximum mission load as only 12.25t/ 27,000 lbs.
Even at sea level, however, increased lift capacity will be important. As the Hummer’s fundamental lack of survivability begins to marginalize it on the battlefield, the Marines are leading the charge to field “MRAP” blast-resistant vehicle designs instead. While an up-armored HMMWV weighs about 9,100 pounds empty, the lightest Category 1 MRAP patrol vehicles check in at weights ranging from 16,000 – 31,000 pounds, and even the “light” JLTVs that will replace a large segment of the Hummer fleet are expected to weigh 14,000 – 20,000 pounds. Those weights mean that tactical operations to airlift mobile forces ashore beyond the beach, or within the zone of operations, will have only one helicopter available that can get the job done: the CH-53.
If the Marines think their existing fleet is seeing heavy use now, just wait.
The most important new addition to the CH-53K will be its GE38 engines. The military is hoping for 18% better specific fuel consumption, even though the engine would produce 57% more power than the similarly sized T64 engine. To improve maintenance and reliability, the GE38 is also expected to have 63% fewer parts.
Other technologies under consideration for the CH-53K include a “glass” [digital] cockpit that has high commonality and interoperability with existing Army and Navy helicopters, high-efficiency rotor blades with anhedral tips that are 11% wider, upgraded engines, a cargo rail locking system; external cargo improvements, survivability enhancements, and enhancements designed to extend service life.
The CH-53K program was going to use a “viscoelastic lag damper” for the rotors, in order to minimize vibration and stress. That was removed, in order to speed up deployment. A modified version of standard linear hydraulic dampers will be used instead. The Navy hopes for 2x reliability compared to the existing CH-53Es, but gave up the potential for 4x reliability.
An Affordable Solution To Heavy Lift [PDF] by Lt. Col. James C. Garman, MH-53E pilot in HMH-772 and a Senior Preliminary Design Engineer in the Sikorsky’s New Product Definition Group, describes the basic outlines of many low-risk CH-53X/CH-53K improvements. See also this interview with former HLR program manager Col. Paul Croisetiere. As he put it in a later NAVAIR release:
“Given the CH-53E’s operational costs and maintenance demands, heavy lift has built its reputation for excellence on the backs of our maintainers… We are going to take our maintainers somewhere they’ve rarely been before. Home for dinner.”
Several decades of weapon program history indicates that this is an unlikely goal. Instead, the trend is that these promises are made, but more advanced and complex weapons have more points of failure, and so require even more maintenance. If the CH-53K program can break that cycle, it would represent a landmark success in Pentagon weapons acquisition.
A Critical Design Review and Technology Readiness Assessments are scheduled for 2010. The first CH-53K, a flight test aircraft, is scheduled to make its first flight in FY 2011. Initial operating capability, or IOC, was originally scheduled in FY 2015 and is defined as a detachment of 4 aircraft, with combat ready crews, and prepared to deploy with all required equipment and spares. That is now expected to happen in FY 2016.