Engineering Drawings

WHAT:

Engineering Drawings are a collection of data related to the design and manufacture of an item or system.  Drawings evolve, maturing as design matures.

The drawings document the level of design maturity achieved and are used for future development; as well as supporting quality assurance functions, maintaining configuration, and procurement of spare parts and systems.  Engineering drawings are the major source of technical information for logistics support throughout a system's life cycle.

There are four types of drawings:

• Conceptual Drawings.  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.  The drawings are used to determine if the requirements are feasible.
• Developmental Drawings.  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/weapon systems developed from a concept.  They are not intended for, nor are they adequate for use in, the competitive procurement of component parts.
• Product Drawings.  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.
• Commercial Drawings.  A commercial drawing package is for end items 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.

A Decision Tree provides a process for selecting the appropriate type drawing requirements to be placed on contract.

WHEN:

Whenever there is any design development involved, engineering drawings are created to document the design.  Engineering drawings should be acquired when the Government is paying for development/production to capture the design paid for.  For developmental programs or commercial programs with some development included, the Government is paying for design/development and should obtain ALL the drawings for which it paid.

Conceptual drawings may be appropriate when there is a high technical risk for the development/design and the Government needs to have confidence that the contractor's design effort is feasible.

Developmental Drawings are considered when the contractor is developing a developmental model/prototype for delivery/evaluation before a production decision is made.  Product Drawings are the drawings needed for the Product Baseline.  They are not accepted until after the Physical Configuration Audit is completed and all audit findings and drawing discrepancies have been corrected or resolved.  (See notional engineering drawing timeline)

Commercial Drawings are not acquired for commercial acquisitions where there is no development effort, as the Government would not normally have rights to the data.  In lieu of drawings, the contractor would be required to deliver maintenance manuals and provisioning information (Provisioning Parts Lists and Engineering Data for Provisioning) to support the logistics strategy and maintenance concept.

WHO:

It is ultimately the responsibility of the Program Management Team to obtain the necessary engineering data needed to support a system.

Contracting for Drawings.

• The Program Support Directorate (PSE-A) personnel located in Albany are responsible for providing guidance in this regard.  The following services are normally provided:
• Development of contract requirements (SOW paragraphs, CDRLs, TDP Option Worksheet with tailoring requirements to the DID)
• Assignment of drawing numbers
• Review and acceptance of drawings
• Signing the drawing sheets on behalf of the PM.

Entering Drawings to the Configuration Status Accounting Activity.

• The Program Support Directorate (PSE-A) personnel located in Albany send the accepted master drawings to the CSA Activity.
• The CSA Activity signs the DD Form 250 receiving the engineering drawing package; loads the drawing package into JEDMICS^[1]; and enters the configuration status information into CMIS ^[2].

The Program Manager or his designated data manager is responsible for signing the DD Form 250 approving the contractor delivered drawing package and authorizing payment to the contractor.

HOW:

Terms and Definitions

General References

Specific References

• MIL-STD-100, DoD Standard Practice for Engineering Drawings (Cancelled and replaced by ASME Y14.100 and Y14.34M)
• ASME[3] Y14.24M, Engineering Drawing Types
• ASME Y14.34M, Associated Lists
• ASME Y14.35M. Revisions to Engineering Drawings
• ASME Y14.100M, Engineering Drawing Practices
• Statement of Work, CDRL, and Tracking Tool (SCATT),
• Engineering Drawing 101 – Introduction to Requirements for Engineering Drawings

Drawings are prepared and delivered by the contractor in accordance with the Contract Data Requirements List (CDRL) and the specified Data Item Description (DID).  A DD Form 250 is used by the contractor to document Government acceptance and approval of the drawings.  A Process Flow for Drawing Approval shows the actions and activities involved in reviewing and signing drawing sheets, approving drawing packages, and submitting drawings for incorporation into the Configuration Status Accounting activity systems.  When Government format and numbers are required, the contractor should request a block of numbers.  Electronic samples can be provided upon request.

To obtain access to JEDMICS, a request must be submitted to the Supply Chain Management Center at Albany, GA.

Do's

• Insure requirements for engineering drawings are in place if the Government is paying for any development
• Get guidance from the engineering drawing experts
• Insure requirements are enforced
• Insure drawing requirements include how proprietary items will be documented
• Maintain the configuration management of your system after fielding

Don'ts

• Confuse the requirements for engineering drawings with the requirements for Engineering Data For Provisioning (EDFP) and Provisioning Parts List (PPL)
• Believe that drawings are not needed for equipment just because it has Contractor Logistics Support
• Agree to changes in drawing requirements without first getting guidance from the experts
• Ask for drawings without putting requirements in place (especially in contracts with developmental laboratories)
• Cite the standards required for engineering drawings as "for reference/guidance only"

Lessons learned – Engineering Drawings

Engineering Drawings Vs. Data For Provisioning - As engineering drawings are often used for provisioning purposes, care must be taken not to confuse requirements for engineering drawings with Engineering Data for Provisioning (EDFP) and Provisioning Parts Lists (PPL).  Each has its own intended purpose.  Drawings are prepared to the level of design while provisioning data is to the level of maintenance.

Commercial Off-The-Shelf /Non-Developmental Items - 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.

Changes to Engineering Drawing Requirements – Many times changes to requirements for product drawings are offered or recommended as methods for reducing costs or improving delivery schedules.  Care should be taken in changing/reducing the requirements placed in the contract, as the majority of the time, the ability to support future procurement of the parts will be affected.

Levels of Engineering Drawings – Many people are still using the outdated "Levels" (Level 2 and 3) to describe/discuss engineering drawings.  This creates much confusion as the new terminology relates to the design maturity a system has achieved.  There is no correlation between the old levels and the new terms (concept, development & product).

Product Drawings and Proprietary Rights – There is a common misconception that when product drawings are required, the contractor is required to release rights in data or proprietary information to the Government.  The fact is, items developed at the contractor's expense or proprietary to the contractor are documented in performance terms within the product drawing package by the use of vendor item/control drawings.

Commercial Items and Drawings - As discussed earlier, drawings are not needed where COT/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.

Engineering Drawings and MIL-DTL-31000A – Many people believe that since waivers will not be approved for the use of MIL-DTL-31000A, drawings cannot 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.  The use of MIL-STD-100 does not require a waiver as it has been designated by DoD as a standard practice.

National Stock Numbers and Engineering Drawings – Many people believe that 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.  The original EDFP and PPL data, if retained, can assist in the reprocurement of parts when drawings are not available.

[1] Joint Engineering Data Management Information and Control System

[2] Configuration Management Information System

[3] American Society of Mechanical Engineers

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