Issue No. 4, Oct-Dec
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Focal Product Support: Commitment, Cooperation, Communication A SERVICE PUBLICATION OF The Lockheed Aeronautical Systems Company LOCKHEED AERONAUTICAL Product Support organization is determined to provide SYSTEMS COMPANY the highest level of service to each of our customers and every one of our airplanes. This level of support Editor is focused toward our personal commitment to our Charles I. Gale customers, quick and open lines of communication to provide information and receive feedback from our Art Director customers, and full cooperation with our customers Cathy E. Howard to develop a team approach to support. Vol. 20, No. 4, October-December 1993 The support arena has undergone vast change in John Gaffney recent years and LASC Product Support has had to CONTENTS evolve to keep pace and meet our customers’ needs. This evolution has resulted in the customer becoming 2 Focal Point more and more prominent in the market place, competition intensifying, and change John L. Gaffney, Director itself becoming constant. LASC Product Support Product Support has made changes and continues to make changes to respond 3 Ramp Hook Retainer to market conditions. Our customers indicated they wanted: Mislocation Playing mix and match with the A “one-stop shop” for all support services. We have become that “one- hook retainers makes cargo ramp stop shop.” Any element of support needed by a customer can be rigging an exercise in frustration. obtained from a single source within LASC Product Support. 10 Making a Ramp Hook Retainer Competitive prices. We are finalizing teaming arrangements which will Identification Tool allow us to offer customers a full spectrum of parts-new, used, and This locally manufactured shop aid overhauled-at competitive prices, all under the auspices of the original can correctly identify the retainers equipment manufacturer. even when they are installed. Quick response times on requests for spare parts quotes. We had been 17 Hercules Operators Update able to respond on an average of 30 days. We have continued to reduce A new Service News feature that time, and we have set a goal of reaching two days or less within the section offers maintenance updates next six months. and news notes of interest to all Hercules operators. Continued superior delivery performance. Our spares delivery performance is above 99%, and we are aiming higher. Covers: Scheduled for delivery later this We are interested in your ideas. How are we doing? What can we do better? year, the first of eight new C-l 30 airlift- If you have any comments or suggestions, let me know. You can call me directly ers being built for the Wyoming Air Na- at I-404-494-31 11, fax me at l-404-494-751 8, or write me at LASC, Dept. 62- tional Guard is put through its paces over 10, Zone 0213, Marietta, Georgia 30063. I look forward to hearing from you. the Lockheed manufacturing facility at Sincerelv. Marietta, Georgia. These new H-models represent the most advanced C-l 30s ever built, with new, high-tech navigational, defensive, and operating systems. Photos John L. Gaffney by John Rossino. Director, LASC Product Support J. L. GAFFNEY - DIRECTOR FIELD SUPPLY TECHNICAL RM&S CUSTOMER SUPPORT SUPPORT PUBLICATIONS DESIGN TRAINING C. A. McLeish J. L. Bailey A. G. Hunt H. D. Hall S. S. Clark C-130 RAMP HOOK RETAINER MISLOCATION by MSgt David E. Crerar Wyoming Air National Guard he cargo ramp and door system of the Hercules troops, vehicles, and supplies to be paradropped to Taircraft is a purpose-built, ruggedly designed feature wherever they are needed. When the ramp is closed and that is one of the many assets that make the C-130 the locked, it seals tightly for pressurization, and in effect world’s favorite multipurpose airlifter. Like the airplane becomes part of the fuselage structure. itself, the ramp is highly versatile. Its design permits a wide range of adjustment during loading operations. Locking the Ramp Cargo can be transferred to and from vehicles of almost any height, and the ramp can be lowered completely for Proper functioning of the Hercules ramp system is direct access from the ground. in many ways dependent on the functions of its locking system. When a modern aircraft is pressurized and This versatility extends to flight operations as well. flown at altitude, its airframe normally undergoes a The ramp is designed to be opened in flight to allow certain amount of distortion. This results in dimensional Lockheed SERVICE NEWS V2ON4 3 changes and alterations in the relative positions between the longeron at these three stations. This arrangement is the airframe components. The cargo ramp locking required because all ramp latches are set at a constant system of the Hercules airlifter is designed to ac- angle relative to the flat floor of the ramp. The hook commodate such changes and still maintain positive retainers at stations 8 and 10, L and R are on a straight ramp locking and good pressure sealing. portion of the longeron. In these cases there is no difference in angle between the locking lugs and the In order to lock securely, and also distribute the retainer bases or the flats at the tops of mounting hole resulting structural loads to other parts of the airframe bosses. evenly, the entire system must be properly aligned and rigged. Complete ramp rigging procedures are spelled As soon as the primary cause of our ramp rigging out in the appropriate maintenance documentation for difficulties was recognized, the ramp hook retainers the various models of the Hercules aircraft. T.O. lC- were measured to determine their true identity. After 130B-2-2, for example, contains the procedure that measurement, they were carefully marked with a felt- applies to many C-130s operated by the U. S. Air Force, tipped pen and then installed in their correct locations. Air Force Reserve, and Air National Guard. The locking system of each of the affected cargo ramps was then rerigged and the aircraft released for flight. Although the details of the rigging procedure may Mission aborts and maintenance writeups involving the vary from model to model, all start out with the cargo ramp disappeared virtually overnight. fundamental assumption that the correct hardware is installed in the correct locations in the aircraft. Only More Than Just Chance when this is the case can the adjustments required in carrying out the ramp rigging procedure yield In reviewing what we had learned in the process of predictable results. Unfortunately, experience has solving this problem in our aircraft, it seemed to us shown that this assumption is not always justified. unlikely that such a large proportion of the C-130 aircraft assigned to the Wyoming ANG should show this Exercises on Location same discrepancy purely as a matter of chance. Sure enough, based upon our contacts with other C-130 Several years ago, we at the Wyoming Air National organizations and the opportunities our maintenance Guard (ANG) base in Cheyenne traced a number of personnel have had to examine aircraft belonging to operational difficulties involving missed block times and other units, we believe that the problem of mislocated occasional ground and air aborts to cargo ramp ramp hook retainers is widespread in the Hercules fleet. misrigging. This prompted a special-emphasis maintenance campaign within the unit to investigate and It is not difficult to visualize the consequences of solve the problem. The campaign was conducted on having cargo ramp hook retainers with incorrect each aircraft during isochronal overhaul so that there characteristics installed at various stations up and down would be adequate time available for a thorough study the sloping longerons. Such a situation is virtually of whatever causes might be uncovered. guaranteed to frustrate all attempts to achieve a properly rigged cargo ramp locking system. The findings of this program revealed first of all that none of our aircraft initially passed all the ramp rigging The result can be a plague of such discrepancies as criteria as outlined in T.O. lC-130B-2-2, paragraph 7- warning lights, ramp locks that will not latch in flight, 52, Fig. 7-3. Secondly, we discovered that only two of internal linkage rods bent from excessive ramp closure the nine assigned aircraft had the correct cargo ramp pressures, or locks that cannot be adjusted to the proper hook retainers installed as per the part numbers shown clearance. To better understand the nature of this in T.O. l-C-130B-4, Fig. 87. problem, let us take a closer look at the retainers and the role they play in the system as a whole. Hookretainers werefoundindiscriminately installed at all ten ramp lock stations. The most common Introducing the Hook Retainers misplacement found was a side-for-side swapping of hook retainers at stations 2R and 2L. This is probably so The cargo ramp hook retainers are bolted to the because these hook retainers “look right” when in these sloping longerons on both sides of the ramp opening at positions. The locking lug angles of the hook retainers the aft end of the cargo compartment (Figure 1). They at station 6,4, and 2 on both the left and right sides must serve as strike plates for ramp latches to engage when gradually tilt downward at increasing angles as one the ramp is closed and locked. moves forward at each of these stations. The result has a rather odd appearance to the untrained eye. Of the five hook retainers on each sloping longeron, three have individual, distinct angles on the locking lug Actually, the retainers are engineered this way to portion of the retainer to compensate for the slope of the compensate for the diminishing radius of the curve of longeron.