Focal. TOM in Product Support A SERVICE PUBLICATION OF LOCKHEED AERONAUTICAL SYSTEMS COMPANY. Editor Charles I. Gale. Art Director Anne G.

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2 A SERVICE PUBLICATION OF LOCKHEED AERONAUTICAL SYSTEMS COMPANY Editor Chares I. Gae Art Director Anne G. Anderson Vo. 18, No. 2, Apri - June 1991 CONTENTS Foca Bob Aycock TOM in Product Support The era of TQM-Tota Quaity Management-has begun, and the resuts have had a significant impact on our way of doing business and on the expectations of our customers. The concept of TQM originated in the U.S., but manifested itsef most strikingy in the business cuture of Japan. The products of Japan have earned the most convincing confirmation of product success: customer satisfaction. That success story needs no further description, but it contains a esson that can be app anywhere, The Japanese experience shows the immense an energetic program dedicated to impementing the principes of TQM across a broad spectrum of industria enterprises. It aso demonstrates the dramatic way in which TQM can enhance a manufacturer s abiity to meet the requirements of his customers Foca Point Bob Aycock, Manager, Product Support Star Quaity Program Engine Run Safety A practica guide to safe engine maintenance runs. Identifying GTC and APU starters They may ook simiar, but these starters are not interchangeabe. Eiminating NLG Fucrum Bearing Noise A reativey simpe repair can often eiminate NLG taxi noises. A New MLG Emergency Tiedown Fixture This new fixture offers sturdy support in MLG emergencies. Fap Jackscrew Interchangeabiity A handy guide for determining functiona equivaencies in fap drive components. Photographic Support: John Rossino Cover: Lockheed Aeromod Center and Foster Edwards Aircraft converted this Hercues airfreighter to a comfortabe, up-to-date, passengerconfiguration for Merpati Airines. At LASC, we are fuy committed to every facet of the TQM concept. We ca our TQM program Star Quaity, and we take our program goas seriousy. In Product Support, we have dedicated ourseves to achieving a very specific objective: improving our approach to customer service such that the customer s expectations wi not just be met; they wi be exceeded. How are we setting about to accompish this? To begin with, we are focusing on the basics. We are using TQM's proven methodoogies to identify cost drivers and eiminate inefficiencies wherever they may be found in the Product Support equation. Every day, in every activity we undertake, poicies and processes are being put to the test. Continuous improvement, one of TOM s most important principes, has become a way of ife. But this endeavor can ony succeed if dedication and resove are supported by the skis needed to bridge the gap between the idea and the rea. LASC empoyees are being trained to utiize new toos-statistica process contros, for exampe-to improve our systems and strategies. Our supervisors and managers are activey seeking guideines from the task performers themseves in forma, probem-soving Process Action Teams. Increasing empoyee invovement eads to a strengthening of capabiities at the point where the work is actuay being done. It is one of the surest ways of achieving fundamenta improvement in the tota quaity of products and services. These efforts are aready paying off in Product Support and throughout LASC. An indication of how we we are progressing is the Contractor Bue Ribbon awards that we have received from the Warner Robins. San Antonio, and Ogden Air Logistics Centers. We take specia pride in these achievements, but we know that it is just a beginning. Our commitment to TQM through our Star Quaity program is permanent and open-ended. It is part of a soemn pedge that our word-cass customers wi aways receive the wordcass support they deserve. Sincerey, Robert E. Aycock, Manager Product Support Star Quaity Program H. L. BURNETTE DIRECTOR FIELD SUPPORT SUPPLY SUPPORT TECHNICAL PUBLICATIONS RM&S DESIGN CUSTOMER TRAINING J. D. Adams J. L. Baiey A. G. Hunt H. D. Ha S. S. Cark

3 by R. M. Guidice, Senior Engineer Product and System Safety Engineering Department A C- 30 ros over its chocks and continues on for 300 yards before hitting a hangar. Another Hercues jumps its chocks, runs into a power cart, veers off the ramp, and hits a tree. In a third incident, a C-130jumps its chocks and hits another C- 30. A tire breaks out, and both aircraft are burned beyond repair. The scenarios may sound improbabe, but these and a number of simiar events have a happened during a famiiar and unremarkabe activity: the maintenance engine run. The post-maintenance engine run is basicay a routine procedure. It is performed safey iteray hundreds of times per week throughout the Hercues feet, a over the word. Unfortunatey, there are aso times when critica points of safe procedure are forgotten, overooked, or otherwise eft out of the process. Too many Hercues aircraft have coided with obstructions or each other, and have been damaged beyond economica repair after their engine-run crews ost contro. Among major Hercues ground mishaps on record, the engine run is the most common scenario. Weighing the Cause Factors Investigation of these mishaps has reveaed some common threads or cause factors that emerge repeatedy in cases of engine runup incidents. Typicay, they invove: Faiure to foow estabished procedures. Inadequate system knowedge. Insufficient training. Let us examine these cause factors more cosey and see what kinds of preventive remedies can be offered. The first cause factor is most often manifested when the crew does not foow the before starting engines checkist propery. What happens next is that the auxiiary hydrauic pump switch may not be turned on with emergency brakes seected, or the brake seector 3

4 This aircraft was damaged beyond repair as the resut of an engine-run accident. Inadequate training is the singe most important cause of such mishaps. switch may be eft in the norma position. This resuts in the engines being started with no main anding gear brake pressure avaiabe. The second cause factor is evidenced by two very common misconceptions. The first misconception is that once set, the parking brake wi hod the aircraft for an indefinite period of time, even without the aircraft hydrauic system being pressurized. This, of course, is untrue. When the parking brake is set and the aircraft hydrauic systems are shut down, the brake pressure sowy beeds off through the system return ines. Within two hours, the parking brake wi no onger be effective. Faiure to understand this point has ed some crews to set the parking brake and then turn off the auxiiary pump with emergency brakes seected, ony to have the aircraft jump the chocks at a ater time when a high power setting was appied. training wi prevent most of these types of probems from deveoping. Up, Over, and Away It is worth noting that the forces attempting to move the aircraft during an engine runup are quite significant. One is wing ift. Fifty-four feet, or 41% of the tota wing span, is swept by the diameter of the propeers. The wind bast generated by the props suppies a arge amount of ift with this much wing area affected. This The wing of this airifter sustained severe damage when it stuck a hangar after the engine-run crew ost contro. The other common misconception is that chocks wi hod the aircraft under power. This is aso not true. Chocks were designed to prevent an aircraft from roing out of its parked position when the aircraft is competey shut down. Ony the brakes can hod the aircraft with engine power appied. The third cause factor is inadequate training. That inadequate training is at the heart of many engine-run mishaps is amost painfuy obvious. Investigations have reveaed that when faced with sudden, unexpected movement of the aircraft, the engine-run crew often simpy did not know what to do. Athough there was no mafunction of any aircraft system, a disastrous coision with another soid object usuay resuted. Thorough 4 Lockheed SERVICE NEWS V18N

5 force is trying to ift the aircraft up and over the chocks. This tendency is even more acute at ighter gross weights, and reativey ight gross weights are normay the case during a ground runup. Another is thrust. Under standard-day conditions, each T56-A-15 engine and 54H6O prop produce approximatey 9,650 pounds of static thrust at fu takeoff power. With a four engines running, this amounts to 38,600 pounds of thrust acting on the aircraft. This combination of thrust and ift can easiy cause the aircraft to cimb up and over ordinary chocks if the brakes are not appied. Under these conditions, the airpane wi aso acceerate at a rate that can starte anyone not accustomed to the takeoff performance of the Hercues. It is for these reasons that Lockheed recommends that engines be run to fu power ony in symmetrica pairs during maintenance checks. With a quaified piot on board, the trainee shoud practice taxiing the aircraft, using the brakes, and reversing the propeers. The trainee shoud experience the acceeration rate accompanying a norma takeoff ro. The training program itsef shoud incude the foowing procedures: Locating the aircraft in an engine runup area cear of obstaces. (The iustration at the bottom of this page and the text on page 6 provide more detaied information on this). Briefing the crew on emergency procedures, incuding those actions to be taken shoud the aircraft jump the chocks. Mishap Prevention There are two areas in which any operator can make significant strides in ground mishap prevention. The first is ceary in the area of training. The engine-run crew is just as important as the fight crew when it comes to training, for it is the same mutimiion doar asset that is entrusted to both. The instruction both receive shoud be commensurate with that responsibiity. Some guideines to foow when setting up an engine run training program are: Foowing a norma checkists appropriate for the appicabe mode of Hercues. Ensuring that quaified personne occupy both piot seats. Ensuring that a engine-run crew members in the fight station are wearing seat bets, and have seats adjusted so that maximum brake peda defection can be achieved. Verifying that proper brake pressure is avaiabe with the auxiiary system pump turned on prior to setting the parking brake. The training shoud incudea norma and emergency procedures invoved with ground operations of the aircraft. Ensuring that the auxiiary hydrauic pump is on with emergency brakes seected, from before engine start unti after engine shutdown. Lockheed SERVICE NEWS V18N 5

6 Propery designed, cage-type chocks can go a ong way toward preventing jumped chocks incidents. Upgrading Faciities As important as training is, operators aso shoud not negect the importance of proper physica faciities in the prevention of engine-run mishaps. Aircraft shoud be parked for engine runs in an area that has either bast defectors or adequate space aft of the aircraft free of a objects ikey to be moved by the propeer bast. This area is defined in the appicabe Hercues operations handbook. Even more important is an obstruction-free area in front of the aircraft that is defined by a 60-degree cone with sides 600 feet in ength. Sometimes innovative approaches wi prevent the deveopment of potentiay dangerous situations. When C-130 production began at Lockheed s faciity in Marietta, Georgia, it became obvious that some unusua protective measures woud be necessary to prevent jumped chocks incidents. Ramp space arrangements made it necessary to run engines on aircraft that are parked approximatey 300 feet from and facing toward hangars. To prevent mishaps, a unique chocking system was devised. It consists of very arge, cage-type chocks which pin into stee pates anchored to foundation bocks in the ramp (see photo above). Aircraft cannot ro up and over these chocks. Once the main anding gear tires are up against them, the aircraft is competey secure. Sound knowedge of aircraft systems and adherence to we thought-out procedures wi aow safe ground engine run operations and hep ensure the protection of costy airift assets. 6 Lockheed SERVICE NEWS V 8N2

7 Iden tif ying A PU and G TC Starters There are severa ways to te which is the correct starter instaation. The most obvious is the part numby Dare1 A. Trayor, Service Anayst Coordinator Airift Fied Service Department Historicay, there has been some difficuty in distinguishing between APU and GTC starters for the various modes of Hercues aircraft. This has been of particuar concern in feets where some aircraft are equipped with APUs and others with GTCs. The starters for the APU and the GTC are neary identica in appearance (see photos above), and it is physicay possibe to insta either starter on either unit. Confusing the two types coud ead to a rea probem, however, because the starters rotate in opposite directions. Instaation of the wrong starter coud damage the starter and possiby the starter input shaft. bers. Part number starters are used on the PN APU, and PN starters for thepn S APU. On the GTC, usepartnumber , -6, or -9 starters, as appicabe. A cose visua inspection of the cutch ratchet on the starter wi indicate the direction of rotation, but an easier way to determine the direction of rotation is to examine the starter end cap and note the position of the brush rigging screws reative to the ground termina. As shown in the accompanying figure, there is a 90-degree difference in the aignment of the brush rigging screws on the two different starters. Carefu attention to these detais wi hep precude damage to the units and ensure smooth maintenance operations. The position of the brush rigging screws reative to the ground termina is a usefu kev to identification Lockheed SERVICE NEWS V18N2 7

8 ELIMINATING NLG FULCRUM BEARING NOISE by W. F. Starkey, Customer Suppy Liaison Representative Suppy Saes and Contracts Department Hercues operators occasionay report hearing grinding or popping noises coming from the vicinity of the NLG whee we of certain aircraft during taxi. These noises can be annoying, and their origin is often difficut to track down. Random mechanica sounds are readiy transmitted through the meta structure of the fuseage, and the ambient noise eve makes pinpointing the exact ocation difficut. Troubeshooting NLG taxiing noises can turn out to be a time-consuming and exasperating affair, and frustration sometimes eads to overreaction. In one case, an operator removed and repaced an entire NLG assemby to get rid of grinding noises that were originating in the forward part of his airpane during taxi. The strategy worked, but such a drastic-and costy-expedient is usuay unnecessary. An aircraft that is written up for unusua NLG noises during taxi shoud first be systematicay checked to eiminate a the more obvious candidates for noise generation. These woud incude such items as oose bots, worn whee bearings, tire or whee imbaance, and uneven tire pressures. After a of these possibiities have been rued out, another potentia cause shoud be considered. Grinding or popping sounds from the nose whee we during taxi may indicate the presence of wear in the PN YTA106A fucrum anti-friction bearings. These bearings have a number of critica functions to perform. They must support the weight of the nose of the aircraft during andings and operations on the ground, and they must aso operate smoothy during extension and retraction of the NLG strut. 8 Lockheed SERVICE NEWS V18N2

9 In addition to the stresses imposed by these important functions, the NLG fucrum anti-friction bearings are ocated in an area where they are exposed to a host of abrading and corrosive agents such as sand, sat, dirt, dust, and ice. Over a period of time, these environmenta hazards can take a to. It is no coincidence that the aircraft affected by wear in these areas have usuay been in service for a number of years. To check the condition of the fucrum anti-friction bearings, disassembe the NLG strut to the extent necessary to gain access to the bearings. Be sure to foow proper procedures as outined in the maintenance manua appicabe to your aircraft. Once the anti-friction bearings have been removed and ceaned, examine them for cracks, corrosion, and wear. The wear wi often be found to be uneven, with much of it concentrated in areas that have been supporting most of the oad. Worn bearings shoud be repaced. The inner race of new bearings shoud be ubricated with a fim of fresh, genera-purpose grease. If the inside diameter of the outer race is Tefon-ined, ony the inside diameter of the inner race need be ubricated. The strut shoud then be reassembed as described in the authorized maintenance instructions. If new bearings are not immediatey avaiabe, a temporary soution that wi usuay eiminate the noise is to rotate each bearing 90') and reinsta it. This serves to expose a different area to the oad, which ensures a better fit and heps protect the aready affected areas from further wear unti new bearings can be instaed. Hercues nose anding gear assemby-note PN YTAO6A anti-friction bearing. Lockheed SERVICE NEWS V8N2 9

10 i by Roy H. Webber, Staff Engineer Supportabiity Technoogy Department Aircrews a over the word know that the main anding gear (MLG) of the Hercues aircraft is a remarkaby sturdy and reiabe performer. In neary four decades of service in some of the most difficut operating environments on the panet, the Hercues MLG system has compied an enviabe record of safe and dependabe operation. But even the best and most rugged mechanica systems are subject to damage and interference from foreign objects, and the Hercues MLG is no exception to this rue. Occasiona damage which compicates owering the gear does occur. MLG Extension Backup Strategies It is for this reason that so many backup strategies are provided for the MLG extension system. They hep ensure the continued safe operation of the aircraft in the event of a MLG probem. In many cases where an eectrica mafunction prevents the MLG from extending propery, the aircrew can manuay acutate the anding gear contro vave to restore service. If this tactic is not successfu, or hydrauic pressure has been totay ost, the MLG can be extended manuay to accompish a safe anding. Gear extension probems that arise from mechanica damage or foreign object interference often require a quite different approach. When foreign objects jam critica components or the anding gear is otherwise mechanicay disabed, it is not aways possibe to ower the struts sufficienty to ensure a safe anding by using either the hydrauic or the manua gear extension systems. In such cases, disconnecting the vertica torque shaft universa joints may aow the gear to free-fa into position. If the gear wi not drop far enough using this strategy, the gear can sometimes be owered the rest of the way by using the emergency extension wrench suppied with the aircraft to rotate the screw jack on each anding gear strut. 10 Lockheed SERVICE NEWS V18N2

11 Figure 7. Norma anding configuration: the drag pin has fuy engaged the shef bracket (view ooking inboard). Securing the Latera Loads MLG emergency extension procedures are covered in detai in the authorized fight manuas for the Hercues aircraft, but a have the same basic objective: to ower the gear far enough so that the drag pins wi fuy engage the shef bracket. The drag pins react to much of the fore, aft, and side oads of anding and must be in proper position to ensure a secure and stabe anding configuration (Figure 1). If it proves impossibe to ower the gear far enough for the drag pins to engage the shef bracket fuy (Figure 2), or in situations where the shef bracket itsef has been damaged, some other method of securing the gear against these oads must be found. Historicay in such cases, aircrews have had to thread 0,000- or 25,000- pound capacity tiedown chains through the ower access pane openings in the whee wes and tie the anding gear struts on either side of the aircraft firmy together. This serves to hod them against the atera forces that might otherwise tend to drive the struts outward when side oads are appied during the anding. Empoying tiedown chains for this purpose works satisfactoriy when done propery, but there have aways been a number of compications associated with their use. For one thing, the chains are buky and difficut to maneuver through the access pane openings. They must aso be inked very tighty to be effective, which can present a safety hazard in case of sippage. Another probem is working room to secure the chains. A oaded cargo compartment is not usuay a very convenient pace to route severa sets of reinforcing chains. In Figure 2. In this case, the gear has not descended far enough for the drag pin to engage. Lockheed SERVICE NEWS V8N2 11

12 Figure 3. The MLG Emergency Tiedown Fixture for Hercues aircraft, PN normay configured tanker aircraft, with the fuseage tank occupying the midde of the cargo compartment, it is neary impossibe. A Better Aternative Fortunatey, there is now a highy practica aternative to the use of tiedown chains to secure the MLG struts in such situations. It is the MLG Emergency Tiedown Fixture, PN This unit, which has now been in production for about a year, is designed as a handy, easy-to-use repacement for standard cargo tiedown chains in MLG emergencies. The fixture is much quicker and simper to insta than the chains, particuary when the airpane is fuy oaded with cargo, and comes in a sturdiy constructed, compact case that is easy to carry and store (Figure 3). Equay important, stress anaysis has shown that the PN I tiedown fixture is significanty stronger than tiedown chains when used for this purpose, and more effective in securing the gear in position when the drag pins do not extend far enough to engage the shef brackets. Description and Use The PN unit consists of a short aoy stee beam, a hooked rod with a knured nut, a stee strap with a hook retaining pin, and a hoding too. In use, the pin Figure 4. The tiedown fixture strap in position, as seen from the MLG whee we. Lockheed SERVICE NEWS V18N2

13 Figure 5. The tiedown fixture s aoy stee beam propery positioned, as seen from the cargo compartment. end of the strap is inserted through the ower access window and guided around the affected strut with the hep of the hoding too (Figure 4). The hooked rod is inserted through the stee beam and can engage the hook retaining pin in the end of the strap when the beam is hed positioned at the access window (Figure 5). The knured cyindrica nut on the hooked rod is used to tighten the strap assemby and rod to the stee beam (Figure 6). Piers or a pipe wrench can be used on the knured knob to appy additiona tension on the stee strap. Landings with the MLG Emergency Tiedown Fixture instaed require observing the same restrictions that appy when chains are used; these are described in Figure 6. The PN I tiedown fixture fuy instaed. RETAINER CABLE the fight manua appicabe to your aircraft. A norma anding approach shoud be fown after notifying the contro tower of the difficuty and requesting that crash, fire, and rescue equipment be aerted. The minimum sink rate is used prior to touchdown, and the use of brakes shoud be avoided after contact with the runway. No attempt shoud be made to turn or taxi the aircraft unti the anding gear configuration has been made secure. The Lockheed MLG Emergency Tiedown Fixture, PN , has been approved for use by Lockheed Engineering. Ordinariy, two of these units shoud be obtained for each airpane in which they wi be used. For further information concerning the operation of this unit, and for ordering information, pease contact: Customer Suppy and Business Management, Dept 65-11, Zone 0577, Lockheed-LASC, Marietta, GA 30063; Teephone ; Fax ; Teex LOC CUST SUPPL. ASSY STRAP RETAINER ACCESS PIN DOOR PANEL Lockheed SERVICE NEWS V18N2 13

14 by Tom Zembik, Service Anayst Airift Fied Service Department The wing faps are vita contro surfaces which extend to produce more ift by increasing the wing area and camber. This added ift serves to improve attitude contro of the airpane when fying at ow speeds. On the Hercues, two outboard and two inboard fap sections are ocated under the traiing edge of each wing. They are powered by pressure from the utiity hydrauic system, which drives a singe hydrauic motor. Power traves from the motor via the reduction gearbox, torque tubes, and jackscrews to drive the faps. No. 41 chaincouping with a 0.50 pitch, diameter x 0.25 roer, and a 16-tooth pitch diameter sprocket. Differences in appearance are not important. In a fap drive assembies that are identified as interchangeabe, the jackscrews and gearboxes are aso interchangeabe, regardess of manufacturer. With continued use, the fap jackscrews tend to wear on the surfaces where the shaft rotates inside the ba nuts. The operation of the jackscrews makes it possibe to raise and ower the faps. These jackscrews work in concert with the 90 gearboxes, connecting inks, and ba nuts which move up and down on the jackscrews as the wing faps are actuated. With continued use, jackscrews tend to wear on those surfaces where the shaft rotates inside the ba nuts, as we as in the bumper regions. The norma 50% fap takeoff and 100% fap anding settings wi aso tend to concentrate wear in these areas. Over time, this wi necessitate remova of the jackscrews and their repacement with new, compatibe units. Some Hercues operators have a combination of fap drive parts in their inventory and wi find it usefu to know which of these parts they can interchange. A parts must meet the technica requirements set forth by Lockheed Specification Contro Drawing In particuar, a jackscrew assembies must have an ASA 14 Lockheed SERVICE NEWS VSN2

15 The tabe beow shows a isting of part numbers and vendor cross references which shoud prove hepfu when you need to determine the interchangeabiity of the wing fap jackscrew assembies authorized for use on the Hercues aircraft. Using the Tabe To use the tabe, first ocate the Lockheed part or vendor part number for the unit you wish to repace in coumns 1 through 4. A assembies isted in the same row are interchangeabe. The tabe can aso be used to find additiona equivaent fap drive assembies. Continue aong the row to coumn 5 and match the aternate Lockheed part numbers isted there with the Lockheed part numbers shown in coumn 1. A assembies isted in the same rows as the matching coumn 1 entries wi aso be interchangeabe and acceptabe as substitute parts. The author and the Service News staff wish to thank Frank D. Middeton of Lockheed Engineering for his assistance in the preparation of this artice. LOCKHEED Part No. SARGENT Part No. WESTERN GEAR Part No. CALCO (CEF) Part No. LOCKHEED At. Part No. Actuator Position EA-O (1,2) 1641 E90(1) ,-13 Outboard EA-1 ~ 1642E85(1) Inboard (3) 457EA-5(1) ,-9,- 3 Outboard (3) 457EA-6(1) ,- 1,-1 5 Inboard (3,4) 4344EA-1, ,-5,- 3 Outboard (3,4) (3,4) 4344EA-2, ,-7,- 5 Inboard 8446M ,-9 Outboard (3,4) 8445M ,-7,- 5 Inboard 1 No further procurement panned by Lockheed. 2Service Buetin A updates 457EA-0 and 457EA-1 to the faisafe configuration of 457EA-5 and 457EA-6. 3 The -5,-7, and up actuators (and equivaent components under vendor PNs) are equipped with a faisafe nut per LER , 4 The -9,- 1,- 3, and -15 actuators (and equivaent components under vendor PNs) are extended ife units and the preferred spares. Lockheed SERVICE NEWS V18N2 I5

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