ENGINEERING DRAWINGS

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Table of Contents

INTRODUCTION

The Program Support Directorate (PSE-A) personnel located in Albany establish engineering drawing requirements for Statements of Work and Contract Data Requirements Lists for Marine Corps procurement programs.  These requirements are provided to the Program and Data Managers for contractual implementation.

The information on the following pages is provided to help Program Managers, Project Officers, and Logistics Managers better understand the requirements and needs for engineering drawings.

LEVELS OF DRAWINGS

Level of Drawings – In 1975, DoD-D-1000B established three levels for defining engineering drawings; Level 1 – Conceptual and Developmental Design, Level 2 – Production Prototype and Limited Production, Level 3 - Production.

Much confusion arose between the differences between the requirements for Levels 2 and 3.  What was required in a level 3 package that wasn't required in a level 2 package?  The requirements were open to interpretation.  Level 1 and 3 requirements were clearly understood.  Depending on who you were talking to, the definition of what was required for level 2 drawings would best be categorized as anywhere in between the other two levels.

In an unsuccessful attempt to clarify these issues, Amendment 3 to DoD-D-1000 added an Appendix in 1983 titled GUIDE FOR APPLICATION AND TAILORING OF THE SPECIFICATION.  Ultimately, DoD-D-1000B was cancelled and superseded by MIL-T-31000 in 1989.  This deleted what was known as level 2, separated what was level 1, and redefined the three levels as Conceptual, Developmental, and Product drawings.  This document finally clearly defined the three levels.  In addition, Commercial drawings were added.

MIL-T-3100 was inadvertently cancelled without replacement on 1 June 1996 and then subsequently reinstated on 9 August 1996.  On 9 June 1997, MIL-T-31000 was reclassified as a detail specification, MIL-DTL-31000A, in order to fit with the new acquisition reform guidelines.  As this document is a detail specification (requires a waiver for use), the level/stage of drawings required is defined within the appropriate Statement of Work paragraph instead of reference to the military specification.  Wording is very close to the definition contained in MIL-DTL-31000A.

TYPES OF ENGINEERING DRAWINGS

There are four different types of engineering drawings used in Government for the acquisition of spare parts and end items.  The four types of drawings and associated lists as described in MIL-DTL-31000A are Conceptual, Developmental, Product, and Commercial.  The first three are representative of the state of design maturity which the end item has achieved as it evolves from concept to production.  The fourth type, Commercial, is representative of items for which the design efforts have already been completed.  To help better understand the differences, a brief description of each follows.

CONCEPTUAL DRAWINGS

Conceptual Drawing Package – A Conceptual Drawing Package is a collection of sketches and text that document basic concepts of how an item may be developed to meet operational requirements.

Intended Use – Conceptual Drawings are used to help determine if the basic concept for meeting an operational requirement is feasible.

Requirements – Conceptual Drawings only have to define the concept.  These drawings may be in a graphic form and include appropriate textual information required for analysis and evaluation of the concept.

DEVELOPMENTAL DRAWINGS

Developmental Drawing Package – A Developmental Drawing Package is a collection of data intended to document a specific design approach and the fabrication of a developmental model/prototype for test or experimentation.  These drawings capture the basic design of equipment/weapons systems developed from a concept.

Intended Use – During the System Development and Demonstration Phase, the production contractor uses the drawings as a starting point for additional design efforts.  During the System Demonstration subphase, the Developmental Drawings are used for updating to meet Product Drawing requirements.

Requirements – Developmental Drawings may vary from simple sketches to complex drawings, or a combination of both.  The development of testing/acceptance requirements and the establishment of sources for component parts are not required under this effort.

When are Developmental Drawings needed? – Developmental Drawings should be acquired when the Government is paying for the development of a model/prototype and anticipates competition of the production contract, or if funding is questionable for production.  Normally if the development and production of an item are covered by one contract, Developmental Drawings should not be required.

Cost considerations – Developmental Drawings cost significantly less than Product Drawings as quality assurance, testing, and establishment of sources are not required to be documented within the drawing package.  These drawings are not intended for, nor are they to be used in, the procurement of component parts.  See Appendix A, paragraph 2.

PRODUCT DRAWINGS

Product Drawing Package – A Product Drawing Package is a collection of product engineering data related to the design and manufacture of an item or system.  Product Drawings contain all of the descriptive documentation needed to ensure the competitive procurement of spare parts or end items.

Intended Use – Product Drawings are used to maintain proper configuration control, support quality assurance functions, provide technical data for competitive procurement of spares and end items, and as the major source of technical information for logistics support throughout a system's life cycle.

Requirements – Product Drawings, supplemented by equipment specifications and quality assurance procedures, shall contain enough information to allow any component manufacturer to purchase materials and components, manufacture, test, inspect, and deliver articles identical to or interchangeable with those delivered by the original manufacturer.

When are Product drawings needed? – Product Drawings should be acquired when the Government is paying for development and/or production of an item, component or system to capture the design paid for by the Government.  For example, drawings should be acquired for production of research and development programs that require; 1) additional development, 2) modification to meet specialized requirements, or 3) specialized racking, stacking, and interface requirements.  The impact of not buying Product drawings or tailoring away certain requirements are provided in Appendix A.

COMMERCIAL DRAWINGS

Commercial Drawing Package – Commercial Drawings are drawings for end items that were developed by the contractor prior to the award of the contract at his/her own expense.  Unless the Government purchases rights for these drawings, the drawings provide the contractor's proprietary engineering and design information for commercially developed items, off-the-shelf items, or items not developed at government expense.

Intended Use – As these drawings are normally proprietary to the original contractor, they may only be used for purposes internal to the Government; such as, development of repair and maintenance procedures, determination of safety requirements, development of test and application program sets, etc.

Requirements – Commercial Drawings are prepared in accordance with the design documentation practices of the contractor or supplier of the item.

When are Commercial Drawings needed?  -  These drawings are normally needed for items that are truly Commercial Off-The-Shelf/Non-Developmental Items (COTS/NDI).  Unless the Government purchases the rights for these drawings, this type of drawing cannot be used for procuring spare parts or end items.  As the purchase of rights if normally cost restrictive, this type of drawings should only be acquired when the end item and its components are to be supported by the contractor for the life cycle of the equipment, the Government did not pay for any development, and no competitive procurement of parts using these drawings is anticipated.

If life cycle support by the contractor is not wanted, acquisition of product control drawings or performance specifications is recommended as an alternative method for supporting procurement of spare parts for this type of equipment.

PRODUCT DRAWINGS AND PROVISIONING DATA

As mentioned earlier, product drawings are drawings that are acquired for the purpose of documenting the design of the equipment purchased for use in procurement and a variety of other functions.  Provisioning Data, better known as Engineering Data For Provisioning (EDFP), is made up of product drawings, catalog pages, commercial drawings, photographs, sketches, or any other form that provides the descriptive information needed for assignment of National Stock Numbers (NSNs).

Even though EDFP may contain engineering drawings, cost less, and serve to fill the initial issue of spare parts, the data should not be confused with the product drawings required for the long-term support of the equipment.  Most contracts that contain requirements for product drawings should also have separate requirements for EDFP.  The requirements for these two deliverables should not be treated as the same.  Each has its own intended purpose and neither can be used in place of the other.  Figure 1 below is provided to show some of the differences between the two.

ENGINEERING DRAWINGS IN SUPPORT OF COTS/NDI

The strategy currently being used by the Government is to reduce the costs required to buy equipment by purchasing COTS/NDI.  This reduction comes largely from elimination of costs associated with design and development.  As discussed earlier, the main purpose of engineering drawings is document the equipment design where the Government paid for development.  Therefore, engineering drawings are not normally required.

Possible alternative solutions for engineering drawings in support of COTS/NDI equipment for different acquisition strategies are provided in the following sections.

COTS/NDI EQUIPMENT ACQUIRED WITH LITTLE OR NO MODIFICATION

Where equipment is being purchased with little or no modification, engineering drawings for use in competitive procurement are normally cost prohibitive and should not be acquired.  Purchase of spare parts will normally be sole source to the original manufacturer.  The following options apply.

• Acquire no engineering drawings or performance specifications and depend on contractor or reverse engineering for support of the equipment.
• Acquire Commercial Drawings for purposes internal to the Government, (i.e., development of test equipment/sets, organizational maintenance, limited configuration management, etc.).  Depend on contractor or reverse engineering for support of the equipment.
• Acquired tailored Product Drawings to include Control Drawings/performance specifications (See Appendices B and C) for the end item and its major components.
• Acquire performance specifications in lieu of drawings.  (See Appendix C)
• Pay the original manufacturer for his design/development and acquire full disclosure unlimited rights Product Drawings.

COTS/NDI EQUIPMENT ACQUIRED WITH MARINE CORPS UNIQUE MODIFICATIONS

Where equipment is being purchased with Marine Corps unique modifications (i.e., rugidization, racking and stacking for use in vehicles and shelters, development of interface devices/cables, etc.), additional design and development will be required by the manufacturer. Engineering drawings to document the effort completed at Government expense should be acquired.  The following options apply:

• Acquire tailored Product Drawings to include Control Drawings/performance specifications (See Appendices B and C) for items developed at contractor's expense and full disclosure drawings for items developed at the Government's expense.
• Acquire Product Drawings to include unlimited rights for items developed at Government expense and limited rights for items developed at contractor expense.  The proprietary drawings would be limited to uses internal to the Government.  Items covered by drawings with limited rights would require contractor support or reverse engineering for procurement.
• Pay the original manufacturer for his design/ development and acquire full disclosure unlimited rights Product Drawings.
• Acquire performance specifications.  (See Appendix C)
• Acquire Commercial Drawings for purposes internal to the Government and depend on contractor or reverse engineering for support of the equipment.
• Acquire no engineering drawings or performance specifications and depend on contractor or reverse engineering for support of the equipment.

COMMON MISCONCEPTIONS

Good Level 2 drawings are all that is needed

Many people still use the antiquated term of "Level 2" drawings.  Even within the DoD community the term is still commonly used.  In lieu of providing Product Drawings contractors offer to provide "Level 2 Plus", "Good Level 2", or "Level 2 Modified" drawings that will serve the same purpose at a lower cost.  The term "Level 2" was replaced by "Developmental" in 1989.  The new definition clearly states that these drawings will not suffice for the competitive procurement or manufacture of spare parts and end items.

Product drawings require the contractor to divulge proprietary information

While Product drawings may require that proprietary information be provided if the Government pays for the rights in data, this does not necessarily mean the Government is asking for the rights whenever Product drawings are specified.  Product drawing requirements provided for Marine Corps equipment do not require the contractor to release rights in data or proprietary information (as shown in Appendix D).  In lieu of this information, control drawings (like what is provided in Appendix E) are required which define items in performance terms such as form, fit, and function.  For items developed at Government expense, full disclosure drawings should be required.  No proprietary information should be provided for items within an Engineering Data Package (EDP).

For example, in COTS/NDI equipment a Product drawing package would consist of a top drawing showing the assembly and configuration of the end item, control drawings for each commercially developed piece of equipment, and full disclosure drawings for the racking, stacking, interface devices/cables, and all other items developed at Government expense.

Once an NSN is assigned the part will always be available and drawings will not be needed.

Just because an NSN has been assigned doesn't mean that drawings are no longer needed.  Once parts that were initially provisioned have been expended, the engineering drawings are used for the purchase of additional spare parts.  If engineering drawings are not available for use, the parts must be purchased from the original manufacturer or an alternate source if available.  If the sources no longer manufacture the item, are not interested in providing the part, or have gone out of business, the part must be reverse engineered to develop the engineering data or the NSN cancelled.  (See also Product Drawings and Provisioning Data).

Drawings are not needed to support COTS/NDI equipment

As discussed earlier, drawings are not needed where COTS/NDI equipment is purchased with little or no modification, but in most cases equipment purchased for Marine Corps usage requires additional development to interface with existing equipment and/or installation in a shelterized or field environment.  Since contractors do not normally continue to stock parts uniquely required to support the Marine Corps, they have very little interest in retooling to remanufacture.  Engineering data should be acquired.  One of the most common problems related to the support of equipment is where engineering data is not purchased for items developed at Government expense.

Waivers will not be approved for Engineering Drawing requirements; therefore, drawings can not be acquired

While it is true that use of MIL-DTL-31000A in defining requirements for engineering drawings in contracts requires a waiver, this does not mean that drawings should not be purchased.  Drawings may be acquired by removing reference to the detail specification, extracting the applicable requirements, and placing them in performance terms in the Statement of work.  Even though many government specific requirements will not be enforceable, the majority needed to acquire a competitive package will.  Use of MIL-DTL-31000A "for guidance only" is not recommended.  The effect of this is the same as having no requirements at all.

SUMMARY

There are four different types of drawings as defined by MIL-DTL-31000A.  Conceptual Drawings document a design concept; Developmental Drawings document the design and development of a model/prototype; Product Drawings document the design and development necessary for manufacturing; and Commercial Drawings documents items developed at contractor's expense.  Of the four types, only Product Drawings support the competitive procurement of end items and spare parts.

As engineering drawings are often used for provisioning purposes, care must be taken not to confuse requirements for engineering drawings with those for engineering data for provisioning (EDFP).  Each has its own intended purpose.

COTS/NDI acquisitions require creative decisions to be made on how items are to be supported.  The DoD policy encouraging maximum competition, in many cases, conflicts with other policy that encourages procurement of existing commercial items.  Based on these decisions and the degree to which the item is truly commercial, there are several methods of acquiring engineering drawings for COTS/NDI equipment.

Contractor logistics support, life of equipment buys, warranties, guarantees, and promises are not intended for the long-term support of equipment.  The logistics community deals with problems created from the lack of data to support equipment on a daily basis for equipment that outlives its intended life.  These problems directly relate to the availability and readiness of Marine Corps equipment.

In determining and enforcing requirements for engineering drawings, managers and contracting officials should work closely with the Program Support Directorate (PSE-A) personnel located in Albany.  These personnel are available to assist managers in establishing the degree of competition and developing requirements for the acquisition of the appropriate engineering data and rights.

APPENDIX A

CHANGES TO REQUIREMENTS FOR PRODUCT DRAWINGS
THE IMPACT OF SUPPORT

Impact of not acquiring a Product Drawing Package – The most frequently encountered impediment to the internal support and competitive procurement of weapon systems and support material is the non-availability of adequate and accurate product drawings.  Changes to engineering drawing requirements can lead to the procurement of unusable spare parts, sole source support, reverse engineering, unreliable or inoperative equipment, or multiple configurations of the same item.

Cost considerations – A substantial amount of contract dollars is spent on technical data.  The Product Drawings, as the major component, are one of the most expensive data items purchased in the course of a system's acquisition.  Emphasis must be placed on the logistic support problems caused when adequate engineering data is not acquired, as opposed to reduction in contract costs related to tailoring of drawing requirements.  Below are listed some of the most common changes offered by contractors for reduction in costs and the impact of the changes to the Government.

1. Change – Use of contractor's format in lieu of Government format.

Impact – Due to the contractor retaining the original drawings and master patterns:

1. Control of the Government's configuration is virtually impossible to maintain.  After delivery of the Engineering Data Package (EDP), the Government will have little or no control over contractor changes.  Parts purchased using the contractor's part number may not work in the Government's configuration.
2. Competitive procurement of printed wiring boards is more costly as master patterns will have to be redeveloped.
3. The EDP cannot be maintained to reflect the latest configuration.

2.  Change – Downgrading drawings from Product to Developmental.

Impact – The following problems are created for the entire EDP;

1. The requirement for vendor item/control drawings is deleted.  (See paragraph 3 below.)
2. Developmental drawings do not provide the necessary design, engineering, manufacturing, and quality assurance requirements necessary to enable the procurement or manufacture of an interchangeable item.
3. Additional design effort is required for support of the equipment.

3. Change – Removal of requirement for vendor item and control drawings. (Vendor Item/Control drawings are drawings of items purchased by the contractor from other vendors.)

Impact – As no drawings will be available for items purchased off-the-shelf:

1. The contractor may offer a CAGE, part number and a short 3 to 4 word description instead.  The following problems are created:
1. No dimensional information is given to describe the physical characteristics of the item (i.e., interface, material, mounting and mating characteristics).
2. No performance characteristics or test requirements are given.
3. The accuracy of the remaining EDP cannot be determined due to the missing information as described in 1 and 2 directly above.
4. No alternate sources are provided creating a sole source of supply.
5. If the sole source alters configuration of the part, goes out of business, or no longer produces the part, reverse engineering will be required for support.
2. If catalog pages are provided instead, the following problems are created:
1. The information provided is usually proprietary and cannot be used for procurement.
2. Again, paragraphs3.a.(4) – (5) apply.

APPENDIX B

VENDOR ITEM/CONTROL DRAWINGS

Definition:

Vendor Item/Control Drawings – An engineering drawing that discloses sufficient information to ensure identification and procurement of interchangeable items.  The drawing shall include as applicable:

1. configuration, defined pictorially or by description;
2. dimensions of item envelope and their limits;
3. mounting and mating dimensions and their limits;
4. interface characteristics and their limits;
5. acceptance criteria;
6. performance, maintainability, reliability, environmental, and other functional characteristics;
7. schematic, interconnection, or other appropriate diagrams to define item function or provide interconnection information;
8. a manufacturer and item identification listed as a source of supply.  – ASME Y14.24M, Types and Applications of Engineering Drawings

Simplified Definition:

A vendor item/control drawing is an engineering drawing that provides only that information which will describe what is wanted/needed.  The drawing should not be a full design disclosure drawing of the item identified as the source of supply; rather, the item identified as the source of supply should meet the requirements of the drawing.  The vendor drawing should not define what you have, but the engineering information you needed to choose what was chose.

Figures B-1 and Appendix D are samples of full disclosure drawings.  Figures B-2 and Appendix E are samples of vendor item/control drawings.  The basic differences between the two as discussed throughout this document are displayed.

The contractor's full disclosure drawings provide specific details on how to build the item.  As the information is proprietary, the appropriate stamps are affixed.  If these drawings were purchased, they could not be used for procurement purposes.  Use would be limited to internal purposes only.

The vendor item/control drawings provide information that tells what the item must do.  There is no proprietary information on the drawings.  These drawings can be used for competitive procurement.

In addition, the drawings show the difference between level of repair and level of design as mentioned earlier in the section on Product Drawings and Provisioning Data.  Even though the vendor item/control drawings allow for procurement of the items, they do not provide information on any down parts.

Figure 2 – Sample of Contractor Formatted Full Disclosure Drawing

Figure 3 – Sample of Marine Corps Formatted Vendor Item/Control Drawing

APPENDIX C

VENDOR ITEM/CONTROL DRAWINGS AND PERFORMANCE SPECIFICATIONS

Definitions:

Performance Specification – "A specification that states requirements in terms of the required results with criteria for verifying compliance, but without stating the methods for achieving the required results.  A performance specification defines the functional requirements for the item, the environment in which it must operate, and interface and interchange characteristics."  - MIL-STD-961D, Defense Standardization Practices.

Vendor Item/Control Drawing – See Appendix B.

Similarities:

• Both performance specifications and vendor item/control drawings provide a means for procurement of equipment based in terms of performance rather than specific "how to build" requirements.
• Both may be used as a means for establishing and maintaining configuration control.
• Both allow for the purchase of state of art technology.
• Both allow for competitive procurement of assembly.

Differences:

• Vendor Item/control drawings do not have to go through the DoD Standardization Program coordination process for approval/change, and are maintained for approval/change and are maintained as a DoD document.  These specifications do not have to be processed through the Engineering Change Proposal process.

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