Replacing The Aging CH-46 CSC 1993 SUBJECT AREA - Aviation EXECUTIVE SUMMARY Title: Replacing the Aging CH-46 Author: Major Gary L. Willison, United States Marine Corps Thesis: The Marine Corps currently recognizes that CH-46 helicopters are no longer capable of conducting the medium lift mission. The Marine Corps must replace these helicopters with a fleet of aircraft capable of conducting the mission for the next 25 years. Background: Marine CH-46 helicopters are now technically obsolete and are rapidly approaching the end of service life. Outdated systems and growing maintenance concerns emphasize the need to replace these helicopters with aircraft capable of performing medium lift missions well into the 21st century. Inadequate payload, insufficient fuel endurance, and primitive navigation and communication systems limit the aircraft's capabilities. The cockpit lighting system is incompatible with night vision goggles. To correct the medium lift problem the Marine Corps is exploring two replacement alternatives for the aircraft. The primary alternative is the MV-22 Osprey, a tilt- rotor aircraft. The second alternative is the purchase of existing or new helicopter technology. Acquisition of the MV-22 instead of a helicopter alternative is more expensive, causing a debate over which aircraft to purchase. The MV-22 satisfies the forecasted needs and requirements of the Marine Corps for the next 25 years. The less expensive helicopter options do not meet the range and airspeed requirements of the future. Acquisition of a helicopter replacement for the CH-46 will only be an interim solution to the medium lift problem. Recommendation: The Marine Corps should replace the aging CH-46 helicopters with a fleet of MV-22 Osprey aircraft. REPLACING THE AGING CH-46 OUTLINE Thesis: The Marine Corps currently recognizes that CH-46 helicopters are no longer capable of conducting the medium lift mission. The Marine Corps must replace these helicopters with a fleet of aircraft capable of conducting the mission for the next 25 years. I. Problems with the CH-46 A. Inadequate payload B. Insufficient fuel endurance C. Outdated aircraft lighting systems D. Primitive navigation and communication systems E. Increasing maintenance requirements II. CH-46 Replacement Options A. Upgrade existing helicopter technology B. MV-22 Osprey III. Proposed helicopter options A. Alternative aircraft B. New helicopter development IV. Debate over cost A. MV-22 vs. helicopter alternatives B. MV-22 performance and cost reduction studies V. Real-world scenario A. Eastern Exit (NEO in Mogadishu, Somalia) B. MV-22 and Eastern Exit REPLACING THE AGING CH-46 The Marine Corps has used CH-46 Sea Knight helicopters for medium assault support missions since the early 1960's. Over the years these versatile transport helicopters have been used in Vietnam, Beirut, Grenada, the Gulf War, and most recently, Somalia. CH-46's have been used in every humanitarian relief and noncombatant evacuation mission involving Marine Expeditionary Units in the last three decades. In the future, roles and missions assigned by the Warfighting CINCs will inevitably require the continued use of medium lift helicopters. Unfortunately, Marine CH-46 helicopters are now technically obsolete and are rapidly approaching the end of service life. Outdated systems and growing maintenance concerns emphasize the need to replace these helicopters with aircraft capable of performing medium lift missions well into the 21st century. The Marine Corps currently recognizes that CH-46 helicopters are no longer capable of conducting the medium lift mission. The Marine Corps must replace these helicopters with a fleet of aircraft capable of conducting the mission for the next 25 years. PROBLEMS WITH THE CH-46 Many problems with the CH-46 contribute to the aircraft's obsolescence. A major problem with the CH-46 aircraft is the inadequate payload. The CH-46 was designed to accommodate a total gross weight of 24,300 pounds. Recent weight restrictions due to stress on the aircraft's dynamic components have reduced the helicopter's maximum gross weight to 22,000 pounds. The weight restrictions apply to internal and external cargo alike. The resulting payload reduction means that instead of carrying 24 combat loaded troops the aircraft now carries a maximum of 12. Insufficient fuel endurance is another problem with the CH-46. The aircraft has to refuel every 90 to 100 minutes. In a shipboard environment, while conducting an over-the- horizon heliborne assault, CH-46's have to refuel every time they return to the ship. This causes a delay in the rapid buildup of combat power ashore, particularly at night or in adverse weather. Internal cells or expanded stub-wing fuel tanks adding 60 to 90 minutes of endurance are often used, but the additional fuel significantly reduces available payload. The standard CH-46 cockpit lighting system is not compatible with night vision goggles. Before flight operations requiring goggles, a blue light kit suitable for night vision devices must be installed over the cockpit instruments. Installation of the kit is inconvenient and time-consuming. Pilots have difficulty reading the cockpit instrumentation because the kit does not adequately illuminate all the instruments. Most pilots must rely on tiny lights known as lip-lights mounted on their helmets to help them see the cockpit gauges. The searchlight on the CH-46 requires an infrared lens to make the light compatible with night vision goggles. This lens is mounted by squadron avionics personnel when the cockpit blue light kit is installed. After installation, if pilots must fly without goggles, the searchlight is not visible to the naked eye. This situation is a potential flight hazard, particularly when landing at an unlit field or zone. The CH-46 is not equipped with a dual searchlight system that would enable the pilot a choice while airborne. The pilot is limited to the searchlight configuration existing on the aircraft prior to launch. Navigation and communication systems on the CH-46 are primitive and unreliable. The Automatic Direction Finding (ADF) equipment is outdated and inaccurate. The TACAN system is only accurate to one half nautical mile because the Distance Measuring Equipment (DME) is not digital. Modifications have been made in recent years to add LORAN and Global Positioning Systems (GPS) to the aircraft. Since the aircraft was not originally designed with these navigational devices, they are mounted in awkward positions in the cockpit. The inconvenient locations increase pilot workload. The CH-46 lacks essential state-of-the-art navigation equipment necessary for adverse weather conditions and demanding night operations. Maintenance of the CH-46 has become a monumental problem with the aircraft. It is increasingly difficult to get replacement parts. Maintenance man-hours per flight- hour have gone from 17 to 40. Nondestructive Inspections (NDI) are necessary after every 10 hours of flight. This time-consuming task requires skilled technicians to inspect each rotorhead for cracks. Undetected cracks in the rotorheads could lead to catastrophic failure. The CH-46 is no longer cost-effective to operate. Marine Expeditionary Units (Special Operations Capable) are currently deployed around the world ready to respond to any crisis in support of the Warfighting CINCs. CH-46 helicopters are deployed as integral parts of these units. These aircraft will participate in any contingencies that may occur. The technical obsolescence of the CH-46, however, reduces its capability to support assigned missions. The missions often require flight operations in poor weather or at night. The missions require pilots to navigate over greater and greater distances in unfamiliar areas of the world. Expectations of mission success are high. With the New World Order comes a renewed focus on the littorals. The recent deployment of forces to Somalia reinforces this "from the sea" concept. CH-46 squadrons continue to provide support, even though the helicopters are no longer capable of performing the medium lift mission. The weight restrictions placed on the aircraft coupled with poor fuel endurance make them little better than utility helicopters. In an expeditionary situation such as Somalia, operations employing CH-46 support will require many forward refueling points. Clearly, the Marine Corps lacks a medium lift assault support aircraft that can conduct assigned missions into the 21st century. The Ch-46 cannot adequately support over-the- horizon missions at night or in adverse weather. The CH-46 is not reliable from a maintenance perspective. It is not equipped with the latest technologies in communications and navigation equipment. The CH-46 is not fully compatible with night vision goggles. It is not equipped with a dual searchlight that is functional with or without goggles. The aircraft does not have enough fuel endurance and can only transport 12 combat loaded Marines. CH-46 Sea Knight helicopters are no longer capable of conducting the medium lift mission. CH-46 REPLACEMENT OPTIONS Recognizing this need to replace the fleet of aging CH- 46 helicopters, the Marine Corps plans to correct the medium lift problem with one of two replacement aircraft alternatives. The primary alternative is the MV-22, a tilt- rotor aircraft. Marine Corps requirements for this aircraft are in the Joint Services Operational Requirement for the Advanced Vertical Lift Aircraft (JVX JSOR) of April 1985. (6) The second alternative is the purchase of existing or new helicopter technology. Marine Corps requirements for this aircraft are in the Revised Operational Requirements Document for the Medium Lift Replacement Aircraft (MLR ORD) of May 1992. (8) The MLR ORD option was developed after the cancellation of the JVX program. Cancellation of the JVX was due to budgetary constraints. Acquisition of either alternative as a replacement for the CH-46 would improve current Marine Corps capabilities. A careful analysis of the JVX JSOR and the MLR ORD reveals an interesting concept. Procurement of an aircraft meeting the minimum requirements of the MLR ORD will not satisfy the requirements of the JVX JSOR. Conversely, procurement of an aircraft satisfying the minimum requirements of the JVX JSOR will exceed the requirements of the MLR ORD. The MV-22 Osprey is under development specifically to satisfy the requirements of the JVX JSOR. The Osprey will possess the capabilities needed to accomplish assigned medium lift missions into the early 21st century. Many similarities exist between the MLR ORD and the JVX JSOR. Both documents show a need for a replacement assault support aircraft suitable for the conduct of amphibious operations. The aircraft must operate in all climates and will have modern navigation and communications equipment. The documents require internal and external lighting system compatibility with state-of-the-art night vision devices and goggles. Seating for 24 combat-loaded troops and two crewmen, a winch system, and an external hoist system are other characteristics common to both documents. The MLR ORD and the JVX JSOR each requires that the replacement aircraft be capable of conducting external lifts of at least 10,000 pounds. Additionally, the ability to refuel from standard in-flight aerial systems and hover in- flight ship refueling systems is included in both alternatives. MLR and JVX requirements include head-up or helmet-mounted displays of essential tactical, flight, and systems information. Differing requirements between the two proposed alternatives clearly indicate that the MV-22 offers more capabilities. For example, the MLR ORD requires the replacement aircraft to cruise at a minimum airspeed of 180 knots with a desired airspeed of 200 knots. The JSOR requires a continuous cruise speed of 250 knots and a dash speed of 275 knots. Based upon these figures, it is possible to achieve a more rapid build-up of combat power ashore with MV-22 aircraft. In an over-the-horizon scenario, this quicker transfer of combat power ashore can determine the difference between the success or failure of a mission. Another difference between the two options is the requirement for self-deployment. The MLR ORD requires the replacement aircraft to have a self-deployment capability but does not stipulate specific range and time constraints. The JVX JSOR requires the MV-22 to have worldwide self- deployment capability with flight legs of at least 2,100 nautical miles. Although this objective must be accomplished without refueling, internal or external fuel tanks may be used to fulfill the requirement. The aircraft must have oceanic navigation systems and include provisions for weather radar. This ability to rapidly self-deploy on short notice is a distinct advantage of the MV-22. When the Warfighting CINCs are confronted with a crisis response situation, the capabilities of the MV-22 will offer them an extremely versatile option. (5:17) PROPOSED HELICOPTER OPTIONS Several helicopter alternatives to fulfill the requirements of the MLR ORD are being considered by the Marine Corps. These aircraft include upgraded versions of the CH-46, CH-60, CH-53, EH-101, AS-332, CH-47, and a new production helicopter. The existing aircraft all require extensive modifications and upgrades to improve performance characteristics. Even with the additional upgrades, these helicopter candidates do not meet the specified requirements of the MLR ORD. The new production helicopter could meet all requirements of the MLR ORD with exception of the speed and self-deployment capability. A new helicopter incorporating modern technology would take years to develop and would delay replacement of the CH-46 even further. (2) A brief comparison of capabilities between possible replacement helicopters shows that the EH-101 cruise speed of 144 knots is the closest to the MLR ORD requirement of 180 knots. The JSOR requires a cruise speed of 250 knots. The MLR ORD and JSOR require that the aircraft be capable of conducting an over-the-horizon assault with 24 troops as passengers. Only the CH-53 and CH-47 options fulfill this requirement. When comparing each aircraft's individual capabilities it is clear that none of the helicopter alternatives meet the requirements of the MLR ORD. Furthermore, there is not a helicopter that exceeds the others in every category. The faster aircraft do not offer the best lift capabilities. Wide differences exist in fuel endurance and range capabilities. Although any of the proposed replacement helicopters would improve Marine Corps medium lift capabilities, acquisition of such an aircraft would fall short of specified Marine Corps requirements. The replacement helicopter would be nothing more than an interim purchase. THE DEBATE OVER ACQUISITION COST The controversy over which option to follow deals with acquisition costs. An aircraft built to meet the requirements of the JSOR is more expensive than the purchase of a proposed upgrade of existing helicopter technology. In a period of declining defense spending, this issue has become central to the debate over which aircraft the Marine Corps should buy to fill the medium lift void. To save money and still get an aircraft to meet future operational needs, the Marine Corps is conducting trade-off studies to determine if money can be saved by "designing out" features already incorporated in the MV-22 Osprey. These studies are being conducted to see if reductions in performance capabilities will translate into unit cost savings. The focus of the examination is to determine the level of mission degradation that will occur when various reductions in aircraft performance are implemented. Current unit cost for the MV-22 Osprey, as designed to meet the requirements of the JSOR, is $33.4 million. Implementation of all performance reductions currently under consideration would save $6.7 million (in FY92 dollars) per aircraft. (4) Structural changes to the MV-22 are the primary differences being considered in the effort to save money. The most significant of these changes is the replacement of the composite airframe for a less expensive metal frame. Other considerations include less capable avionics packages, the deletion of the vibration reduction system, and a more simplified rotor. Additionally, some of the specialized gear such as FLIR may be available as kits rather than installed in the aircraft upon delivery. (2) Although the trade-off study results are not scheduled to be finalized until August 1993, it appears that cost savings due to performance reductions will ultimately create greater life-cycle expenses for the MV-22. For example, a metal airframe will require extensive corrosion control maintenance over the life of the aircraft. The saltwater environment intrinsic to shipboard operations causes metal aircraft components to rust very quickly. The composite airframe feature of the MV-22 would eliminate this corrosion problem. (4) In addition, elimination of the MV-22's vibration reduction system may cause more rapid deterioration of aircraft components due to the increased vibration levels. THE MV-22 AND A REAL-WORLD SCENARIO Operation Eastern Exit, the January 1991 Noncombatant Evacuation Operation (NEO) in Mogadishu, Somalia, was a real-world scenario in which the MV-22 might have been extremely useful. The mission, although successful, could have been accomplished more efficiently with MV-22 aircraft aboard the USS Guam. The mission required two CH-53E aircraft to fly 460 miles over water to Mogadishu to insert a security force and then return to the USS Trenton. This flight required three aerial refuelings for each aircraft. Communications with the security force in Mogadishu indicated that evacuation by helicopter was needed due to the threat. The USS Guam and USS Trenton continued to steam at full speed towards the Somalian coast to get close enough to begin the evacuation of noncombatants from the American Embassy. Upon arrival, and under the cover of darkness, Marines flying CH-46 helicopters conducted the evacuation with the aid of night vision goggles. The Marine Corps, in a future Eastern Exit scenario, will be able to insert the security force with only one aerial refueling using the MV-22 as the medium lift platform. During the evacuation operation the mission can be conducted sooner since there will be no requirement to place the ships so close to the coast. Additionally, updated communications and navigation equipment in the MV-22 will enhance mission success. Finally, the MV-22 cockpit will be compatible with the use of night vision goggles making the aircraft easier to fly at night. This advanced equipment will decrease pilot workload and increase pilot situational awareness. Pilots will be able to concentrate more on safe execution of the mission. (7:20) In summary, the Marine Corps needs to replace the aging CH-46 with an aircraft that will meet the requirements of the next 25 years. An aircraft fulfilling the minimum provisions of the MLR ORD will only be an interim replacement. The best alternative for the longer term is the MV-22 Osprey. Superior range and airspeed potentials of the MV-22 over the proposed helicopter alternatives create a considerable advantage. These improved capabilities translate into greater flexibility and swifter response to unexpected crisis situations. The MV-22 is the medium lift aircraft best suited to replace the CH-46. BIBLIOGRAPHY 1. Darling, Col. Buck. "Warfighting the V-22." Amphibious Warfare Review Spring 89:26-31. 2. Decisions Options Paper. Aviation Weapons Branch, Headquarters Marine Corps, Washington, D.C. Feb 93. 3. Gisold, Maj. Gary. "The V-22 and the Future Threat." Amphibious Warfare Review Spring 90:18-22. 4. Hanifen, Maj. B. T. Telephone Interview. Aviation Weapons Branch, Headquarters Marine Corps, Washington, D.C. Feb 93. 5. Humston, LtCol. Douglas E. "Over the Horizon-2000." Amphibious Warfare Review Winter 89:17. 6. Joint Services Operational Requirement for the Advanced Vertical Lift Aircraft (JVX JSOR). Department of Defense April 85. 7. Lawrence, Col. W. S. "The V-22 Cockpit." Amphibious Warfare Review Spring 89:20. 8. Revised Operational Requirements Document (ORD) for the Medium Lift Replacement Aircraft (MLR). Quantico, VA: Marine Corps Combat Development Command, May 92.
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