# GKN Revolves Around Aerospace Calculations

## Capturing the rationale of complicated equations

### Background

GKN Aerospace Engineering Services, the United Kingdom's leading aerospace design services organization, offers a full range of outsourced engineering and design services to the aerospace, marine and rail markets. Engineers provide calculations and designs of structures to customers that determine whether parts can be manufactured. These services range from the placement of a single engineer on a permanent or temporary basis to the execution of a total design package.

PTC Mathcad is used at GKN Aerospace Engineering Services by stress engineers who produce calculations and product designs that are shared among customers to check that calculations and designs are free of errors and parts are ready to be manufactured. A key element of this process is the ability to capture the rationale of complicated equations. PTC Mathcad is a visual design environment that allows engineers from all industries to draw from a variety of data sources during the design phase of a product and document all mathematical formulas and calculations.

GKN Aerospace Engineering Services needed a knowledge-based engineering product that could combine the simplicity of a word processor with visual diagrams of equations so customers could easily comprehend design principles and make amends to calculations. Previously, GKN Aerospace Engineering Services was using spreadsheets, which didn't have the capability that PTC Mathcad has to attach visual components.

### Information Can Be Easily Transferred

PTC Mathcad allows engineers at GKN to provide hard-copy calculation sheets as well as digital copy files that can be shared among customers.

GKN's customers benefit from PTC Mathcad digital files because information can be easily transferred, and calculations can be modified if needed. The hard copy is critical in the aerospace industry as it forms a part of contract documents and, in all cases, it is inspected by a validation organization like the Civil Aviation Authority. Once the analysis is complete, the second phase is to validate the calculation to make sure there aren't any errors. This involves complete recalculation to validate the original analysis.

Tony Garcia, principal stress engineer at GKN Aerospace Engineering Services, said, "PTC Mathcad has made our calculation sheets more comprehensible as it conveys analytical intent in a way that was not possible with spreadsheets. PTC Mathcad also allows us to redo calculations and permits customers to modify the analysis using different parameters if required."

### Reusable By Every Engineer

"About 10 or 15 years ago all calculations were done with pencil and paper on traditional calculation sheets," said Garcia. "PTC Mathcad now provides the facility to replicate everything you would previously do by hand but with a PC. Moreover, now that the process is captured digitally, it is much easier to correct mistakes or to repeat a similar analysis using different values.

"PTC Mathcad also has saved us time on training programs, with graduates coming into the company bringing the knowledge of how to use it, since PTC Mathcad is employed extensively at universities."

Most engineers in the technical department at GKN Aerospace Engineering Services use various versions of PTC Mathcad on multiple makes of PCs. "People tend to keep a whole series of PTC Mathcad worksheets instead of using reference notebooks containing their favorite formulas or industry-specific reference books or design manuals," added Garcia. "Once an analysis or problem has been translated or captured as a PTC Mathcad worksheet, it is portable and reusable by every engineer."

### About GKN Aerospace Engineering Services

Aerospace Engineering Services was recently formed from a number of established GKN businesses, including GKN Westland Design Services Limited (Design and Resource Groups) and Westland System Assessment Limited. It operates under the direction of the GKN Central Enterprise Development Unit (CEDU) as part of GKN Aerospace Services. By building on the proven track record of the businesses from which it was formed, Aerospace Engineering Services offers a total engineering outsource service to support customer products from initial concept through the end of their lifecycle. Within GKN Aerospace Services, Aerospace Engineering Services is responsible for the design engineering capability within the group.