VOL.19, NO. 2, APRIL-JUNE 1992

Transcription

1 VOL.19, NO. 2, APRIL-JUNE 1992

2 A SERVICE PUBLICATION OF LOCKHEED AERONAUTICAL SYSTEMS COMPANY Editor Chares I. Gae Art Director Cathy E. Howard Vo. 19, No. 2, Apri-June Foca Point Now at ship 2000 and counting, the Hercues boasts a proud pedigree. 3 Fue Quantities Update The main fue tank capacity vaues given in most of the manuas need updating. Here are the new figures. 8 Instrumentation Test Set This mutipurpose tester wi satisfy today s stringent accuracy and capabiity requirements. Ship 2000! The Line Breeds True Few who witnessed the inaugura fights of the eary C- 30A Hercues aircraft in the spring of 1955 coud ever have imagined it. The very first airpane to ro off the assemby ine is sti in service and earning its keep 37 Years ater. Most woud have been even more increduous had they been tod that the production ine turning out the geaming new turboprops woud aso sti be earning its keep neary four decades ater. And in championship stye! In May of this Year, the Lockheed production faciity in Marietta, Georgia, proudy deivered its 2000th Hercues. It is appropriate that the new owner shoud be the Kentucky Air Nationa Guard. Today s Hercues, an updated and much improved version of the origina, is a thoroughbred in every sense of the word. There is nothing in the history of aviation that even remotey matches the record of the Hercues aircraft. Long the mainstay of both miitary and commercia airift around the word, the Hercues has been in continuous production for more than a third of the time since the Wright brothers taught the word how to fy A New Generator Contro Unit for the Hercues An updated system offers greater reiabiity, easier maintenance, and higher-quaity eectrica power. Simuated Engine-Out Contro Speeds Engine-out simuations invove controabiity factors that deserve cose study and attention. Photographic Support: John Rossino Covers: Our front cover shows the 2000th Hercues aircraft during a test fight. The ground shots on the back cover offer some additiona views of the historic aircraft shorty before it was deivered to the Kentucky Air Nationa Guard on May 15, It was, as some have said, a case of the right airpane at the right time. But in the aerospace business there is no more unforgiving chaenge than the test of time. A record of achievement ike that of the Herk takes a ot more than uck; it has to be earned. It took a unique combination of engineering exceence, designedin versatiity, and uncompromising quaity to transform yesterday s high-tech concepts into today s most capabe airifter. It is no coincidence that the same combination of quaities that opened the doors to yesterday s achievement are aso pointing the way to tomorrow s success. An eary C- 13OA tries its wings over Marietta. J. L. GAFFNEY - DIRECTOR FIELD SUPPLY TECHNICAL RM&S CUSTOMER SUPPORT SUPPORT PUBLICATIONS DESIGN TRAINING J. D. Adams J. L. Baiey A. G. Hunt H. D. Ha S. S. Cark

3 Fue Quantities Update R ecent studies conducted by the U.S. Air Force and Lockheed have shown that the fue capacity vaues given for the Hercues aircraft in much of the authorized documentation need to be updated. Operationa Suppement T.O. C-130B-IS-263 aready refects some of these changes as they appy to USAF airpanes. The tabes that accompany this artice offer a broader seection of data and incude the correct capacities for a tanks instaed in the more prevaent configurations of the airpane. Note that the vaues shown in the tabes for externa tanks are for the Lear Sieger PN 305JOO units, the type currenty being instaed in new production Hercues aircraft. Other kinds of externa tanks wi have different unusabe and usabe fue voumes and weights. The new fue voumes appy to aircraft Lockheed seria number LAC 4542 and up, and to earier airpanes which have had their outer wings repaced with either FY 73 (LAC 4542) or FY 84 (LAC 4992)-type outer wings. Modifications to improve the outer wing structure and update the fue system have contributed to the changes in fue capacities of the main tanks. The changes amount to a reduction of approximatey 3.5% in the capacities of these tanks. The fue quantity indicating system is not directy invoved. Carefu checking has determined that its accuracy is we within the imits required by thespecification. Further studies to estabish the overa effects of the fue quantity changes on the airframe are in progress. Estabishing the New Vaues The Lockheed tests to estabish current tota fue capacities were conducted on two new Hercues airpanes on initia fueing after roout. These aircraft were seected as typica baseine airpanes, and were not equipped with either refueing pods or exposion-suppressant foam. The tota capacities in voume and weight obtained from these studies are shown in Tabe 1. No attempt was made to confirm or revise the unusabe fue voumes in these tests. The tabes thus show the existing unusabe fue voumes, which have been retained, and the resuting usabe fue voumes. JP-4 and JP-5 under standard-day conditions were used as the bases for the weight cacuations. Tabe 2 shows fuei capacities for non-usaf Hercues aircraft equipped with refueing pods but no foam. Tabe 3 contains the voumes and weights for USAF aircraft equipped with foam. For these USAF aircraft, the tota fue figure shoud be understood to mean the by W. G. Moses, Aircraft Structures Engineer, Senior LASC Aeromechanics Department tota capacity minus the fue that is dispaced by the dry foam. Tabe 4 shows the corresponding vaues for USAF C-130 airpanes equipped with refueing pods. The effects of foam on tank capacities were determined by Warner Robins Air Logistics Center. Unusabe Fue - Two Standards The tabes show two sets of unusabe fue voumes for airpanes without foam. Both are in current use. The differences between them arise from differences in the way the numbers have been derived. The first set of vaues are those empoyed by the USAF. These voumes for unusabe fue are the same as originay used for C- 130B and C-130E modes. The usabe fue voumes for airpanes with foam in the tanks appy ony to USAF Hercues aircraft. The other set of figures show the unusabe fue voumes that have been certified by the FAA for civi modes of the Hercues. These vaues are aso used for miitary modes, except for those operated under USAF technica orders. The resuting usabe fue voumes are thus appicabe to most non-usaf Hercues aircraft. Reviewing the Structura-Limit Fue Weights It shoud be noted that the fu-fue weights shown in the tabes for JP-4 (6.5 pounds per gaon) continue to define structura-imit fue weights for aircraft with hard struts. Simiary, the fu-fue weights shown for JP-5 (6.8 pounds per gaon) are the structura-imit fue weights for aircraft equipped with soft struts. Since the main tank voumes are reduced, it might be supposed that a fue with higher density coud be used to produce the same aowabe fue weights as previousy empoyed. Unfortunatey, this is not the case. The purpose of the new outer wing designs was to offer enhanced fatigue resistance in critica areas and incorporate improvements to the fue system. Athough the changes resuted in a better outer wing, some weight was added in the process. Design requirements resut in a tota weight imit for the outer wing which is the sum of the structura, system, and fue weights. The decrease in fue capacity, in effect, compensates for the increased weight of the empty wing. Substituting a fue with a higher density to offset the reduced voume woud therefore not be appropriate and, if used, coud ead to restrictions for ground operation of the airpane. Lockheed SERVICE NEWS V19N2

4 IN U.S. GALLONS TABLE 1. FUEL CAPACITIES -HERCULES AIRCRAFT WITHOUT REFUELING PODS, NO FOAM IN POUNDS (Fue weights based on 6.5 Ibs. per gaon for JP-4; 6.8 Ibs. per gaon for JP-5.) TANK TOTALS UNUSABLE USABLE USAF OTHER USAF OTHER JP-4 JP-5 JP -4 JP-5 JP-4 JP-5 JP-4 JP-5 JP-4 JP Lockheed SERVICE NEWS V19N2

5 IN U.S. GALLONS TABLE 2. FUEL CAPACITIES -HERCULES AIRCRAFT WITH REFUELING PODS, NO FOAM IN POUNDS (Fue weights based on 6.5 Ibs. per gaon for JP-4; 6.8 Ibs. per gaon for JP-5.) Lockheed SERVICE NEWS V19N2

6 FUEL CAPACITIES -USAF C-130 AIRCRAFT WITHOUT REFUELING PODS, WITH FOAM IN U.S. GALLONS LEFT EXT RIGHT EXT I TOTAL IN POUNDS (Fue weights based on 6.5 Ibs. per gaon for JP-4; 6.8 Ibs. per gaon for JP-5.) 6 Lockheed SERVICE NEWS V19N2

7 TABLE 4. FUEL CAPACITIES-USAF C- 30 AIRCRAFT WITH REFUELING PODS AND FOAM IN U.S. GALLONS IN POUNDS (Fue weights based on 6.5 Ibs. per gaon for JP-4; 6.8 Ibs. per gaon for JP-5.) Lockheed SERVICE NEWS V19N2

8 S E by Wiiam C. Turbyfied, Eectronics Engineer, Senior Eectronic Support Equipment Engineering Department T he functionaity and mobiity requirements demanded by today s miitary and commercia aviation communities have created unique probems with regard to test equipment. The equipment used to test aircraft components must be versatie, easiy transportabe, and reiabe. At the same time, it must aso be abe to meet the broad spectrum of accuracy and capabiity standards set by maintenance organizations. Individua pieces of singe-function equipment designed to check specific components may have been acceptabe in the past, but the reaities of today s aerospace maintenance environment are dictating new eves of appicabiity and performance. There is a rea need for a singe, ightweight package that wi combine mutipe testing capabiities. At Lockheed Aeronautica Systems Company, we are meeting this chaenge by buiding a unique, new generation of test equipment. One outstanding product that has resuted from this effort is the portabe, practica, and highy reiabe PN ES Instrumentation Test Set. This test set is a versatie and powerfu unit designed to test aircraft instrumentation components at organizationa, fied, and depot eves. It is housed in a rugged, transportabe case that offers true portabiity. This aows easy transfer of the unit to the particuar repair shop where it is required. When teamed with the PN ES ( ) Interface Kit that contains the adapters and cabes appropriate to the instrumentation being checked, the test set is capabe of functionay testing an impressive variety of indicators and associated transmitters. To be considered truy mobie and mutifunctiona, test equipment must be easy to set up and require a minimum of documentation to operate and maintain. The Instrumentation Test Set estabishes standards of performance in this category. A circuitry for simuating instrument parameters and measuring transmitter outputs are contained in the test set itsef. Instructions to the operator, pu-down and pop-up menus, and on-ine hep are dispayed on the buit-in fat-pane graphics dispay. Operator input is provided through use of the test set s numeric key pad. Depending on the unit under test, seected vaues of simuated parameters are presented on the dispay in an easy-to-read format, as are the measured vaues of transmitter outputs. The software routines necessary to adapt the unit for the particuar instrumentation systems to be checked are oaded into the tester by the use of externa cartridges. These cartridges and the cabe assembies required for interfacing with the capabiities that wi be tested are contained in separate kits. This aows each user to configure the test set for his particuar needs. The PN ES Interface Kit, which aows testing of Hercues aircraft instrumentation components, is avaiabe now. However, provision has been made to expand the test set to accommodate new instrumentation as required. Other interface kits for different aircraft wi become avaiabe as needed to meet customer requirements. This wi greaty increase the tester s vaue over time. In addition to being easy to use and expandabe, the test set aso offers outstanding dependabiity. Incuded among its features are buit-in sef-test and caibration procedures that ensurehigh reiabiity. Simuated signas from the test set are ooped back to monitor circuitry, permitting an interna test of the equipment s operation and accuracy. This type of sef-testing capabiity gives 8 Lockheed SERVICE NEWS V19N2

9 the user additiona assurance that the equipment is functioning propery and providing accurate resuts. When used with the appropriate interface kit, the Instrumentation Test Set provides the means to test the foowing components and systems: Transmitters for pressure systems (oi, hydrauic, and fue) may aso be connected to the test set and checked if an additiona dead-weight tester (not suppied with the test set) is provided. Aieron trim tab position indicators Eevator trim tab position indicators Fue fow indicators Fue fow power suppies Fue pressure indicators Fue quantity indicators Hydrauic pressure indicators Landing gear position indicators Oi cooer position indicators Oi pressure indicators Oi quantity indicators Oi quantity transmitters Rudder trim tab indicators Tachometer generators Tachometer indicators Temperature indicators Torquemeter indicators Turbine inet temp. indicators Wing fap position indicators For further information concerning the PN ES Instrumentation Test Set, and for ordering information, pease contact: Customer Suppy Business Management Department 65-11, Lockheed-LASC, Marietta, GA Teephone: ; Fax Teex LOC CUSTOMER SUPPL Lockheed SERVICE NEWS V19N2 9

10 A New Generato Contro Unit for the ercues by Larry Arnod, Staff Engineer C-130/L-100 Eectrica Design Group T he eectrica power system of the Hercues airifter has recenty been updated to provide the aircraft with a system that wi offer greater reiabiity, easier maintenance, and suppy higher-quaity power to the using subsystems. Beginning with Lockheed seria number LAC 5271, the 40/50 KVA generators instaed on the engines and the APU are controed and monitored by new, PN generator contro units (GCUs). The modifications to the eectrica system required to incorporate the new equipment were designed to have the east possibe impact on the overa aircraft eectrica system instaation. None of the changes affect the generators or any of the associated wiring in the wings and nacees. The GCUs are instaed on the second shef of the underfoor eectrica contro and suppy rack. The new units repace the votage reguators, generator contro/ protective panes, and frequency-sensitive (underfrequency) reays. Looking aft at the shef from right to eft, the GCUs are designated No. 1, No. 2, APU, No. 3, and N O. 4. The aircraft wiring has been changed to route a the signa and contro ines to the generator contro units instead of the ensembe of equipment- votage reguator, generator contro pane, and frequency-sensitive reay-that each GCU repaces. The overhead contro pane in the fight station has aso been modified. The contro switch for each generator is changed from a four-position rotary to a twoposition rotary switch. The new positions are ON and OFF/BESET. Automatic Configuration The GCUs are designed to provide the contro and monitoring of the 40/50 KVA generators instaed on the engines and APU, and to operate automaticay with either the Bendix or the Leand (GE) generator. Each GCU provides the foowing functions: Votage reguation Undervotage monitoring Overvotage monitoring Underfrequency monitoring Overfrequency monitoring Differentia faut protection Generator contactor contro Status ights The votage reguation is designed to provide highquaity eectric power that meets the steady-state and votage transient requirements of MIL-STD-704D. The GCU monitors the permanent magnet generator (PMG) input from the main generator to determine the type of reguation to provide. If the PMG votage is 30 VDC, the generator is Bendix and the reguator for the Bendix generator contro fied is seected. If the PMG votage is 108 VAC, the generator is a Leand and the reguator for this type generator contro fied is seected. This seection is done automaticay and requires no action on the part of the aircraft operator s maintenance personne. With this feature, it is possibe to operate an aircraft with a mix of generator types without having to match the generators to a particuar votage reguator. 10 Lockheed SERVICE NEWS V19N2

11 System Monitoring Each GCU aso provides system monitoring of the generator output and contros the contactor which ties the generator to the aircraft oads. If any of the monitored parameters are outside the design imits, the generator contactor wi be deenergized and the GEN OUT ight iuminated. In some cases, the generator wi aso be deenergized. System monitoring incudes: 1. UNDERVOLTAGE - If votage drops to 95 VAC or beow for more than 4 seconds, the ine contactor wi open, the generator wi deenergize, and the GEN OUT ight wi iuminate. The generator can be reset by pacing the contro switch to OFF/RESET and then back to ON. front ofthe GCU indicates to the maintenance technician which modue to repace. The four LED indicators are used to indicate the nature of a system faiure during BIT and norma operation. If the GCU trips during norma use, the LEDs wi iuminate in a pattern to indicate what caused the system trip. The operator shoud ook at the GCU LED indicators before attempting to reset the system. Norma checkout procedures, as we as troubeshooting, wi be much simper with the new GCU. Prefight checkout wi take a fraction of the time previousy needed and require ony one person. 2. OVERVOLTAGE - When votage exceeds an inverse time curve of 5 vot-seconds above 130 VAC, up to a maximum of 190 VAC, the ine contactor wi open, the generator wi deenergized, and the GEN OUT ight wi iuminate. The generator can be reset by pacing the contro switch to OFF/RESET and then back to ON. 3. UNDERFREQUENCY - If the frequency drops beow 365 Hertz, the ine contactor wi open and the GEN OUT ight wi iuminate. When frequency rises above 375 Hertz, the ine contactor wi cose and the ight wi go out. 4. OVERFREQUENCY - If the frequency exceeds 440 Hertz, the ine contactor wi open and the GEN OUT ight wi iuminate. When the frequency drops to 430 Hertz, the contactor coses and the warning ight wi go out. 5. DIFFERENTIAL FAULT - If the difference between the current at the generator terminas and the current at the contactor terminas exceeds 35 amps, indicating a feeder faut, the ine contactor wi open, the generator wi deenergize, and the GEN OUT ight wi iuminate. The GCU cannot be reset after detecting a differentia faut unti a power sources are removed from the GCU. BIT Capabiity The GCU has buit-in-test (BIT) capabiity which is used to verify that the monitoring circuits are performing propery. The BIT is initiated with a pushbutton switch on the front of the unit. This test can be done at any time that power is on the aircraft, whether the generators are on or not. When the button is pushed, four LED indicators on the front of the GCU wi iuminate for approximatey 10 seconds and then go out if the GCU passes a of the interna tests. If a test fais, one or more of the LEDs wi remain iuminated to indicate that nature of the faiure. An LED truth tabe on the The BIT wi hep to isoate a probem by dispaying information that shows the operator the type of faiure invoved. Troubeshooting is aso simpified by the fact that there are fewer ine repaceabe units (LRUs) in the system. Substitution is aso a practica approach for troube anaysis, since a GCUs are identica and interchangeabe. The new generator contro units are designed to be highy reiabe and easy to maintain. The MTBF for the units is expected to exceed 20,000 hours. This wi significanty reduce the maintenance requirements for this portion of the aircraft eectrica system, and ower the overa cost of operating the Hercues. Lockheed SERVICE NEWS V19N2 11

12 Fight Characteristics and Performance: by M. A. DeCastro Jr., Senior Engineer Product and System Safety Engineering Department W hich of the foowing situations wi produce the highest minimum speeds at which the aircraft can be controed? No. 1 engine faied, propeer feathered. No. 1 engine faied, propeer windmiing. No. 1 engine simuated out, throtte at fight ide. Under certain conditions, the engine-out simuation wi require higher speeds to maintain directiona contro than either of the other situations. Since simuated engine-out approaches and andings are an amost daiy occurrence, it is important for Hercues fight crews to be thoroughy famiiar with this characteristic and what can be done to prevent potentia probems in the traffic pattern. Minimum Contro Speed-Air (Vmca) The Vmca for an aircraft is the minimum speed at which the piot can maintain contro and continue straight fight. It is a precisey defined vaue that is determined by fight test and based on a set of constant conditions. In the case of the Hercues aircraft, the Vmca constants for one-engine faiures are as foows: Maximum power on the operating engines. No. 1 engine inoperative and the propeer windmiing on NTS. Fu rudder defection, or 180 pounds peda force. Five degrees bank away from the faied engine. Gear down. Faps at 50 percent. Minimum fying weight. These are the most critica conditions invoved in computing minimum contro speeds. The two-engine VMCA for the Hercues adds No. 2 engine faied and feathered, beed air off, and ony one hydrauic system operating at 3,000 psi to this ist of conditions. It is important to keep in mind that changing any of these constants wi affect the piot s abiity to contro the aircraft. For exampe, with one engine out, if the wings are kept eve instead of at the prescribed five degrees of bank, the speed at which directiona contro can be maintained increases by 9-12 knots. Simiary, ow rudder boost instead of high boost requires an additiona 13 knots above the charted Vmca for controabe fight. The aircraft cannot be controed at the charted Vmca given in the performance manua if any of the constants are changed in a way that adversey affects controabiity. Propeer Thrust Before we take a coser ook at the effect of engineout (or engines-out) simuations on controabiity, et us briefy examine the question of propeer thrust. We sedom think in terms of thrust in connection with the Hercues because our measure of engine power and performance is normay given in inch-pounds of torque. However, it is in terms of thrust that the physica effects invoved in engine-out simuations are best understood. At takeoff power, the engine-propeer combination produces approximatey 9,650 pounds of thrust per engine under static conditions, and 8,650 pounds at 100 KTAS at standard-day, sea-eve conditions. A propeer produces positive thrust by acceerating the air that passes over its bades. But under some conditions, air can actuay be deceerated when passing through a propeer. When this happens, the resut is a negative thrust vaue. Depending on the airspeed, a propeer at fight ide can produce as much as 2,000 pounds of negative thrust, as shown in Figure 1. Such negative thrust has cear impications for aircraft controabiity, but simpy knowing this as an abstract fact wi not be very hepfu. A thorough understanding of the probem is necessary if this knowedge is to be appied propery. 12 Lockheed SERVICE NEWS V19N2

13 C-130H Minimum Engine/Propeer Thrust vs Speed (Sea Leve - Standard Day) Figure Airspeed - Knots 160 The first thing we can do is convert thrust to some usabe vaue, since we cannot measure thrust directy in the fight station. If we express thrust effects in knots of airspeed, we can then appy a correction to the aready defined vaue of Vmca to derive a new minimum speed at which contro is possibe. Note again that this does not change charted Vmca in any way. We need a corrected minimum contro speed because we ve changed one or more of the constants in the Vmca definition. Simuated Engine(s)-Out Minimum Contro Speeds Figure 1 shows that the negative thrust effect of a propeer at fight ide begins at about 98 knots, hence the minimum touchdown speed for the aircraft in the performance manua. In cases where one engine is simuated out, the effect is such that at approximatey 109 knots the piot must begin increasing the minimum contro speed as the negative thrust makes itsef fet. The increase in minimum contro speed reaches a maximum of 8 knots over charted Vmca as the negative thrust buids toward a maximum of 2,000 pounds, after which the effect decreases to an average of about 5 knots above Vmca (see Figure 2). Athough two-engines-out simuations do require higher Vmca and are more difficut to hande, their reative effect on minimum contro speed is not as pronounced. Figure 3 shows that between approximatey 117 and 128 knots, the thrust effect requires an increase of up to 5 knots over the charted two-engine Vmca Outside of this range no increase is necessary, primariy because both rudder boost systems wi be operating and norma beed air is on instead of off. Throtte Setting Now that we know about the worst-possibe cases, et us see how the negative thrust penaty incurred in training simuations can be reduced or eiminated atogether. Variations in airspeed and propeer rigging resut in a fairy wide range of acceptabe torque (and therefore thrust) vaues for a propeer at fight ide. We can eiminate most of the effects of this variabe by setting the throtte(s) on the faied engine(s) so that torque is zero or sighty above. This does two things. First, it eiminates NTS activation and its accompanying yaw osciations. Second, it reduces the negative thrust enough to decrease the airspeed penaty by at east haf for oneengine-out simuations and eiminate it atogether for two-engines-out simuations. Thus, by setting the torque to zero, ony 4 knots needs to be added to the charted one-engine out Vmvca instead of 8 knots, and the need for any increase to two-engines-out Vmca is eiminated entirey. Figure 1,2, and 3 contain the zero-torque ines that iustrate this effect. Lockheed SERVICE NEWS V19N2 13

14 C-130 Three-Engine Air Minimum Contro Speeds Faps 50%, 180~b Max Peda Force, 5-Deg Max Bank Ange Figure Fight Manua Minimum Contro Speed - KCAS C-130 Two-Engine Air Minimum Contro Speeds Faps 50%, 5-Deg Max Bank Ange +I0 Figure Fight Manua Minimum Contro Speed - KCAS Lockheed SERVICE NEWS V19N2 14

15 Other Considerations Recent wordwide Hercues mishap investigations have shown that too few operators fuy understand the performance characteristics of the Hercues aircraft. Crews are fying into critica situations at atitudes and speeds which make recovery virtuay impossibe. Improper contro inputs during asymmetric thrust situations can cause immediate oss of contro. If yaw is increased rapidy to very high sidesip anges, the resut wi be a drastic oss of airspeed and a rapid ro toward the thrust-deficient wing. Recovery to baanced fight with coordinated contros and symmetric power must begin immediatey and may require as much as 5,000 feet of atitude. Regaining directiona contro is imperative; it may require nothing more than reducing power on the opposite symmetrica engine to something ess than takeoff power, provided the piot recognizes and makes proper aowance for the reduction in cimb performance. Maintaining the minimum speeds prescribed in the performance manua ony ensures that the aircraft can be controed under a very specific set of operationa conditions. Prevention-that is, aways maintaining an adequate speed margin during maneuvering-is the rea key to controing the aircraft. Pubished minimum contro speeds do not afford additiona margins for maneuvering, nor do they guarantee protection from further upsets if the given conditions change. Prompt, precise piot action must occur immediatey to avoid a departure from controed fight in such cases. Weight Recommendations for Fight Crews Make sure you fuy understand the aircraft s characteristics and know how to appy your knowedge in fight. Simpy knowing the performance definitions is not enough. Understand and respect the effects that any divergence from the defined parameters may have on performance characteristics. Use zero torque settings for a engine-out simuations. Aways know both the charted Vmca and the actua minimum contro speeds in a situations. Maintain sufficient contro margins during ow-speed fight. Lockheed SERVICE NEWS V19N2 15

16 -..U Lockheed Aemnautca System$ COmpany Customer Training Systems Department Lockheed - LASC Marietta, GA , 2002, 2003, 2004,...