Production Engineering for the Civil Market Rif R. B. iflcilKTyRE Executive Euiftneer, de Havillaud Ctiitadu HIS paper specifically refers to the civil market so that some of country’s point of view, it would be a serious loss if an aircraft concern wasT the problems of designing, pro- not able to turn its facilities effectively ducing and selling aeroplanes can be to war machines in time of emergency, discussed in terms which are common One point of difference between to most competitive manufacturing en- the civil and military tnarkets is that terprises. In addition, The de Havil- a military agency has some .idea of the land Aircraft company has always kind of aeroplane it is lookinu for and been interested in the civil side of perhaps the quantities it requires, at least initially, whereas in the civil mar ket the aircraft company must, on its own initiative, study the overall market situation and discuss R. B. MeINTYRE as deeply as possible. The final de cision to proceed udth design and pro duction rests solely with the company and the results of this decision are easily measured by standard business yardsticks, as the venture develops. WTere the potential market is made up of a large number of small operat ors. the companv will probably have to make its own financial arrangc- aviation and has accumulated some ex perience in designing for. and selling to, civilian operators. Perhaps the most salutary thing about engaging in the civil market is that the operators, just like the pro ducers, must be commercially respon sible, with clear commitments, and must stand or fall according to their achievements. In an industry which is , young and in which technical develop- j ment is rapid, design progress must I be made quickly enough to meet com- ; petition but not so quickly as to pass ^ outside the reach of the customer's ’● pocket. Sustained commercial solv- ; ency is the criterion by which a com- ● pany mav be judged. ; It has been said that the civil mark- I et involves a producer in excessive } commercial risks. The element of ! risk cannot be denied. Confidence in i the company’s technical ability, esti- ' mation of price and market trends, ; effect of government policy and inter- | national situations—all these must be ' reduced to a calculated commercial risk. However, some of the risk is good since it does provide incentive. Without it there is less interest and ' less real progress. * Close Association; At this point the military side of aviation should be mentioned. While the civil and mili tary are two different spheres, the tech nical problems of the two sides are quite closely associated. It is almost necessary for a concern which wishes to keep in the lead to concern itself cept of the jdan. with both sides. Apart from anv tech- (3) The mechanics of assembly of nical considerations, and from the ' the overall plan. requirements with many different operators, often Thein various countries. companv must then trv to conceive an aeroplane which will penetrate this civil market A Plan for Airframe Production By DEAy 1*. STOWEEL Assistuut to the Presitleut, Canadair LUuiied N TOD.A.Y’S never ceasing search for higher productivity, the con certed efforts of the members of all groups engaged directly or indir ectly in production arc a prime re quisite. To assume fully their share of this total effort, management must ' devise in advance the scheme of action for these groups. It is intended that the scope of this discussion be confined to a study of a pre-formulated method 1 of getting the production job done. .After analyzing the subject, it seem ed reasonable to present three basic I The first fundamental cliaractcristic would seem to he that the plan be all inclusive. That is. it should place a time or quantitative value (or both) on each operation or element of production. It is suprising how often one finds Engineering working to a plan. Tooling working to a plan.- Proc urement working to a jdan. and .Vfanufiicturing working to a plan, on a given project, each going in the same general direction but with no real co-ordination as to lime or effort between the resjiective operations. There should be one plan that forms the central strand, around which ail related operations are woven. It should: (1) -Set forth the objective, (2) Sjiecity how. when and by whom the ]dan is to be executed, and aspects: (1) The fundamental characteristics of such a plan. (2) The data available that will in fluence the frame of reference or con- .-I/RCR.-IFTs ways in which produciion engineering help shorten these intervals and establish the manufacturing program at the earliest possible date. If the production engineer could wait until all design details were sta bilized, until all flight trials had been pleted and Certificate of Air- rthiness obtained, and until all ments. If a large operator is interested in the project it is likely that he will want to participate in the financing scheme in order to secure an option on the early production machines, in no way impede the work of the design organization in turning out a first-class aeroplane, although it rightly gives such a cus tomer much freedom in planning many interior details and special equipment. It also commits the com pany to meet specific delivery dates and prices, and may call for guaran teed performance of the aeroplane. Foresight Necessary: In ail this, the company strives to judge the market for some years ahead because from the time of deciding to design an air craft for a certain purpose to the time when it will be available for delivery in quantity, some years must inevi tably pass. Remembering that aviation is young and rapidly developing, it is important to reduce this interval as much as possible. If a demand exists, the aim must be to fill it quickly before the market situation changes or CREDIT IS DUE can . . , to the Society of Auto motive Engineers, with whose kinri permission these two articles are being reprinted in Aircraft. Both articles were originally presentetl as papers at the SAE International Pro duction Meeting, held in To ronto’s Royal York Hotel last October 29 and 30. This should com wo drawings were issued on a production basis, his work would be greatly sim plified. From a competitive point of before one’s competitors try to fill it. view in aviation this would be an im- Before production deliveries of an aeroplane begin there are two easily recognized intervals: (1) The period from initiation of possible situation because the time in volved would be far too great. We must take it as axiomatic chat time does not permit waiting for all these design to the first flight of the proto- items to be completed before starting production. The trend is towards in creased overlap between the prototype stage and production. Consequently the risks of modification are greatly increased. This overlap, which may not be common to other industries, introduces an interesting relationship between the design and production sides of the company. type. (2) The period from the first flight of the prototype to the beginning of production deliveries. Each of these periods is generally anywhere from 1 to 4 years depending on the size and nature of the aero¬ plane. These time intervals are usually regarded as excessive! It is the main purpose of this paper to discuss the I Continiieil on pane 46) erally in this business it extends over a period of several years for any given program. In each phase of devolpment, the Tools that take longest to build gen erally take more design time and so the last to be released to the shops. Special equipment for testing, because of its long procurement time, must be plan must present a coherent picture, ordered before complete test pro cedures and specifications are avail able. Usually, because of the time element, initial lots of fabricated parts must be released for manufacture prior to completing assembly and installation planning. Custotner programs are not always readily phased into the opti mum manufacturing plans. However, in spite of these difficulties, to fail to set these problems out in their true perspective, one to the other, will surely lead to confusion and cost at a later date. are Major operations are not left un planned nor is the plan allowed to shade oil into vague generalities. When a specific answer is not known, the best possible assumption is made in the light of knowledge at the time. In the early analysis of the plan, it is this second characteristic, evolution through stages, that makes it difficult to attain the all inclusive characteristic. Flexibility a Must: The third funda mental characteristic is that the plan must be flexible. One of the predom inant factors in aircraft production is The second fundamental character- the ever-changing nature of the in dustry. It has been jokingly said that in this business there is nothing con stant but the change. The fact that its detail aitd scope. In its simplest today, after building substantial quan- form. it sets forth the time element cities of one particular model, we are still processing 7^50 changes per week, reminds one that there is a fair amount DEAN P. STOWELL (3) Set up means of appraisal by management. Difficult Objective: This is not easy to attain. The normal release of data throughout the successive steps in the production process does not lend itself to a smooth dovetailing of operations. For example. Engineering necessarily requires more time to design castings and forgings than simple sheet metal details, yet the procurement and fac tory people need these designs first because of their longer flow times. istic is this — the plan must evolve through several phases of develop ment. each of which contributes to ) for the major processes of production, namely Engineering, Tooling and Manufacturing. In its broadest sense, as we shall see later, it embraces the detailed analysis of Men, \fachines aiul Material. It may cover a span of only a few months, but more gen- of truth in this statement. There are many factors that force revision of an otherwise stable pro gram. To name a few. there are: < Continued on page 43) January, 1954 9 ‘difficulty wouhJ be that between the ■north and the south stations, there would be thousands of square miles of territory not covered by radar. Thus, once a hostile aircraft had penetrated the northern screen, there would be no way of telling in what direction it was heading. The net result would be that the alarm would have to to all potential targets, where the possibilities of an air raid would bring about a complete work stoppage, on a nation-wide basis. Obviously, an enemy could make Canada’s industry almost completely inactive, simply by sending aircraft through the northern screen at frequent intervals. These aircraft would not actually have to press home an attack, since in bringing work to a halt, their mission would have been accomplished. In this instance, a “spoof” raid would be as effective as a genuine attack. The apparent answer would be to have radar stations completely blanket ing all of Canada from north to south, and east to west. According to Mr. Claxton: “Rich as our countries are, the combined resources of Canada and the U.S. in men, materials, and money are not equal to undertake such an immense task even if it were possible.” Thus, the McGill fence has been developed. The indications are that it sort of an automatic electronic r i.-rrort fr‘'«nionH of mnti- luicinent k’uve no doiJl>t us to their sincere Hpprec'iiition of the importiiiioe, dixiiily and uni(iucnesH of the indiviiiuii). HiivinK ex|)lorf«i some of the chuniclui i.slics of the plan, wu cun turn our utlention to the seconer day call for a higher proportion _ of hard dies, the breaking down of operations t^'to smaller segments, more positions in the sub-assembly and assembly lines, and pos sibly mobile jigs and moving production lines. Certain programs, primarily miiiury, have as one of the stipulations that such thinking must be embodied in the desi^s for tools and production but that moderation must he practised in the actual production for peace time programs. It is entirely possible for an exceptionally able production and tooling organization to go a long w-ay toward setting up a 20 or 20 ship program on high volume methods without incurring costs in excess of those arising from a more conservative approach. Such an accomplishment would most cer tainly result in a distinct competitive advantage. . , Thus the individual operator is faced with the paradoxical situation that says hand “do something new and bold and dif ferent in order to gain the iiotential iid- the other production growth from initial delivery to peak rale. Highly Accurate: For the detailed analysis of this jiroblcm we are indebtcil to Mr. P. J. Stanley of the College of Aeronautics. Cran- field. Mr. Stanley has exploilelies that the doubling of the cumu lative plane number results in reducing the unit man hour expenditure to 8091 so that if 10.000 direct man hours were expended on the 100th plane, cumulative plane number 200 would require 8.000 direct man hours. If. instead of a reduction from 10.000 to 8,000. the drop is from 10.000 to 7,500 man hours, the trend would desciibe a 75% curve. It is often possible and desirable to analyze the aircraft by the types of labor comprising the total direct labor effort. Each type of direct labor has its own learning curve. Theae. when combined in the proper propor tion. result in an overall learning curve for the aircraft. Thus, presented with a variety of typical learning curves, the individual producer must make the decision as to which one will be used in estimating man hour requirements. The second set of data influencing the frame of reference relates to the rate of and Jai>an. a available to n con- Aside from certain tip of output are of the samc_ those found in other types of build-up. "Using this basic assumi'tion, Mr. Stanley has constructed a family of curves which illustrate a wide range of : . thus variation in the acceleration rate. These curves are identified by a steepness. Once a particular curve has been selected from the family of curves, it is easy to develop a logical calculation of acedera- in steepness and “R” index of I i STEEL AND ALUMINUM FOR AIRCRAFT on one STEEL - tubing stainless, chroniemolv, and low carbon grades, also sheets in stainless and low carbon grades. in vantage available’’, and says hand, “use caution : historical data does not disclose any .successful operation that varies to any considerable extent from custom . However, this is a decision that must be made if we are to complete the frame of reference for the plan. on The fourth set of dataMiscellaneous: . contributing to the concept of the plan is comprised of the miscellaneous assortment of statistics used as jiarametcrs of magnitude Such figures as: (1) the (2) the (3) the and achievement, number of Engineering drawings, numiier of parts and assemblies, number of tools by type, (4) the number of tools per part number, (5) the percentage distribution of man hours by aircraft com ponent, and (6) the amount of material labor dollar, are typical of the statistics ALUMINUM “ bars, sheets and tubes. ]>er falling into this group. As the pieces of the plan are gradually assembled into the whole, this kind of data is used as a check in order that wc may develop a rational picture in all phases of the operation as measured by past perform ance. For example, if our plan is based on release of 20.000 Engineering drawings, the other factors being equal, it is reason able to plan for a related number of tool designs, shop orders, tools, etc. Later in the development of the plan, but still early in the ivciual accomplishment of data is a barometer to indicate changes All to aircraft specifications. a WE CARRY A WIDE VARIETY OF SPECIFICATIO^’S IN SEGREGATED STOCKS AND RELEASE NOTES CAN BE FURNISHED TO DEPARTMENT OF TRANSPORT OR R.C.A.F. REQUIREMENTS I the over-all program, the same used as between actual and assumed conditions. There are, no doubt, many more criteria that influence the decision-making necessary for the conception of a plan. However, the ones mentioned are representative of the other.s and. .suffice to say. the problem is c ( 1 t V SPECIALIZED DRUMMOND, McCALL & CO. LIMITED MONTREAL - TORONTO - WINNIPEG AIRCRAFT44 rni.'iii (lutes lor these -.ume items. '!'» do this. ;i time cycle chart is construcUdl that >ets forth flow times for the first nneJ suhne«iuent air craft in the Drottrum. UsinK times (1) The date of first delivery. (2) The peak jrroduction rate. C{) The acceleration curve to peak produc tion rate. Since time is of the es.sencc in most nir- craft proKram.s, a con.siderution of initial delivery datc.s usually boils down to visualiz- inir a.s accurately as possible what must take place between an assumed contract date and the completion of the first aircraft. In pen- eral. Emrineerintt. Plannintt. ToolinK and Production operations are anticipated and u block of time is allocated for each sufficient to assure operations. The elapsed time allowed for these operation.s is a function of past performance modified to conform to the ternu and conditions anticipated for the proposed proirram. Production Rate: the major assembly manufacturinir these curves and standard lead established for sub-a.ssemhlies, detail raw material and purchased parts.parts, the rtsiuircd completion dates for any part in any static of production can be de termined. When tnc production orders bcKin to flow to the shops, it is es.sentiai that depart mental man loads be developed as a j?uide for hirinii. This is essentially a function of the man hours as determined by the learn- ini? curve, and the scheduled rate of produc tion. These calculations, in conjunction with jitf and fixture calculations, are also used to determine factory space roejuirements. As proccssinic is released, machine loads confirmed and. where necessary, addi tional eliinneerformancc. The reasons may he obvious &c obscure anti the amount of analysis will vary accordinfrly. In nny case, efforts are directed toward keeidiiK a thoiDUKhly realistic, delaiUKl and ui'-to- date nlaii of oi'eralion in the hands of suiiervision at all levels and in all de))art- ments. In conclusion, the nictnre we have nl- lenii’ted to iiresent of "A Plan for Airframe T’mduclion” has for its hold outline the fjictor.s of comprehensiveness, flexibility, evolution, and enlightened work climate. It has for hackiiBound direct man hour i-e- iluctions. acceleration ciuves, production de- siCT and toolitip. and u variety of mis cellaneous statislic.s used as parameters of achievement and magnitude. It is framed in lllock considerations. Preliminary Detail con siderations and Final J>etail considerations, and is hunc on the wall of every super visor in every department involved in the program. This then is the picture ; the shadincs and colorings are infinite as they are directly related to the decisions made by the in dividual oi>erator. . * Ar a i Qjiality-Engineered Aircraft Hoselines and Fittings civil MARKET 1 (Coiifiiiiie/I from page 9) I Manufactured in Canada under license Aeroquip Corporation, Jackson, Michigan L'p and At ’Em Boys: To begin with, the l>roject must not he looked upon as "just another job" to be through. To achieve success all key personnel in the organization must have enthusiasm for their jobs coui>led with an intense faith in the project at hand. This enthusiasm must be ])resent to the great est degree in the design team and the pro duction team immediately as-sociated with the project: for it is from these people that most of the original thought comes and the success of the entire project may well depend on their efforts and ability. There should be no doubt about the imjiort- aiice of getting the i>rntotype into the air as quickly as ixjssihle. flies can the asses-sed and any difficulties cleared is usually at this stage that customers begin to press inquiries for delivery. The produc tion engineers must therefore lend great as sistance in speeding comi>letion of the proto type. Quality-Engineered Hydraulic Controls TPMJENCO PROGRESS AND ENGINEgPING COPPOBATlQN LIWITEP TORONTO. ONTARIO I Only when the jirototype soundness of the design be up. It V 72-7i STAPPORO ST. and it is here that very close liaison is called for between design, experiment and produc tion. If there is time, the final proauction tool should be made but only where the de signer feels that there is not too great risk of change. Sometimes the major portion of the production tool can b“ ma'’e, leaving certain sections "open” for future development as the de.sign becomes stabilized, jhis latter procedure is often successful in the case of the larger assembly fixtures. In the case of formed sheet metal parts it is best to produce drop hammer dies, stretch press dies, Hufford tools and rubber press tools right at the .start. The prototype will benefit from all such parts being prop erly and smoothly formed, and of course the later production benefits because of the tool development which has taken place early in the project. In other ca.ses, temi>orary tools can be made, but here the production engineer can ensure that such tools are adequate for at least 5 or l(i sets of parts which can be used in the initial production. He can also watch the behavior of the temporary tools to get a practical idea of how the production tools can be better designed, (4) The production engineer can observe the way in which various details assemble. Potential production difficulties can be dis cussed with designers and drawing changes pul in train. (5) The production engineer can arrange for some details to be fabricated in the pro duction shops on a short batch basis, relieves the load on and at the same lime begins to make the production departments aware of and inter ested in the new project. Again this is most likely to happen on those parts requiring special equipment such as presses, hammers, furnaces and the like. Modification Problem: In all this there is the ever jiresent risk of modification, amount of risk varies with every corajionent and with every detail of each component. By mean.s of smooth co-operation between design and produclicm these risks can be reason ably well assessed so that pro-'uction can be started earliest on minimum risk items. The succuBsfui completion of structural i--Bt:s and functional mock-up tests are events of great imiiorUmce to the protiuction man. unit iiassc.s test the risk of modification on lhat unit drops In our experience, the real key to the smooth transition between de.sign ami i>ro- duction is the Experimental Department. The main function of this department is to i>ro- duce prototype aircraft. It also deals with normal mock-ups, functional mock-ups, test pieces, structural tests and all special re quirements and develoi>ment work. This de partment should be as self-contained a.s pos sible, should be located close to the design department and be directly responsible to the Chief Engineer. The Experimental Department is also sponsible for prototype the actual flying of course being in charge- of the Chief Test Pilot and the flight programs under the control of the aerodynamics tion of the engineering department. Meeting Ground: The Experimental Depart ment is a kind of common meeting ground for the design and production engineers. During the prototype stage we have found it profitable to station a group of production engineers irght in the Experimental Shop in order to advise on all new details from a jiroduction angle. The following things can be done through this group: (I) Sugge.stions can be made directly to de signers before experimental drawings are pre- pared. These suggestions are made with a view to a certain method of manufacture making maximum use of existing production equipment. If the design demands the use of equiiiment not availaliie in the jilant, early con.sideration can be given to the locating of a competent sub-contractor or the possible- purchase of the reqiiire'd equipment. re- servicing an-i fivi'-g. ON SOURCE INSPEGED BONDED STOCK sec- AN and NAS Screws and Bolts. Out Specialty AN 509 and 525 — NAS 220 through 225. Drilled Fillister head AN 500 and 503, AN 4 through AN 10 diametet Bolts. Close tolerance Bolls. Special Bolts and Bushings. Aircraft Fittings. i 501 502 This the Experimental Shop /2-3 week delivery on mill runs AN 5 thru AN 10. For your requiremenis call— (2) The production group is able to draw ui> schedules of material, particularly cast ings, forgings, and extrusions, which have long delivery time.s thli.s giving the production department an early lead. (3) The production team is able to guide the Experimental Shop a.s to the best way of making the protoly|)(- parts. In some cases freehand m<-lhods can be used. This ajiplies particularly to machine shop items and simide sheet metal it(-ms where inicrclmngcatiiliiy can 111- achieved without tools or where it is not a factor. Mon- oflr-n some type of tiwiliiig is tieeiled The SALES CO., INC. Oiffribufori of Atreroff and Induslrlot Hardware 38 GRANT ST„ BUFFALO 13, N.Y. Telephone As e;icli Elmwood 1568 1569 considerably thus clearing AIRCRAFT46 niiiiiy (lajtiiils for iiroiluution. y Of ooursit there is iuldiliotml ^volvoil by the cJuiilication «f This (lii|>lieiition is broiurht by the for temporary tooliriK.

Production Engineering for the Civil Market

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