lofting of JSF inlet duct

Lofting of Jet inlet duct

loft of space shuttle fuselage

Loft of Space Shuttle fuselage

Example of MDB Loft Book

Example of MDB Loft book

Bayden Engineering Group is the leader in surface lofting services. True Lofting is a dying artform and we are unsurpassed at complex surface creation. The following is a list of some of the Lofting programs Bayden Engineering Group resources have been used on:

  •      Northrop Grumman Inlet Duct
  •      Space Shuttle Left wing (in support of Columbia crash incident)
  •      Space shuttle fuselage
  •      X-33 Fuels tanks
  •      Dehaviland Dash 8-400
  •      Gulfstream G5
  •      Bell Helicopter (Model 230 and 430)
  •      General Dynamics F-16
  •      Bombardier

Select here to see lofting tutorials

In the aerospace industry, conic equations are used to describe the curves that are swept through space to generate surfaces. Conics are the curve of choice since they form smooth surfaces that are capable of creating laminar flow across surfaces. The military has used conics since they are a reproducible curves due to their mathematical equations. In addition, almost all existing aircraft used books full of conic equations to describe the lofts. these  "Master Dimension Books (MDB)" or "loft books"  are the only roadmap's available to obtain the true definition of aero surfaces. Bayden Engineering Groups team of seasoned loftsman are highly skilled at the interpretation of these conic equations and then re-creating the matching surface in today's high end CAD systems.

The advent of 3D surface definition has created surface "Hackers” (No concept of tangency, parameterization, patch count, etc.) who create surfaces that mey appear to be fine but the underlying equations for that surface are bad. Surfaces are the root geometry for all downstream CAD applications (solid modeling, NC programming, etc.). Some companies have attempted to convert point maps back into 3D surfaces which result in:

  • 4th order approximations
  • Gaps between adjacent surfaces
  • Curvature discontinuities
  • Un-usable surfaces for downstream applications A c
  • Curves made up from individual arcs

Bayden Engineering Group is the leader in aerospace legacy program services. Our staff is from the aerospace industry and understands the way programs were completed in the past, and how to use the high-tech tools of the present to transfer the design/build intent from old Mylars and MDB books to useful 3D datasets.

Our procedures for handling legacy lofting data is as follows:

  • We use MDB Mathematical Definition Book to obtain the equations for the conic curves
  • Use High end CAD systems to translate the conic curves
  • Generate surfaces from translated conic curves
  • Parameterize Surfaces from MDB Shapes
  • Bound (trim) generated surfaces labeled to match MDB elements iIdentically
  • Store surfaces into a database for public use

Our Lofting Quality measures include the following procedures:

  • Check for Curvature Control
  • Check for Tangency Control
  • Check for Dimensional Accuracy
  • Check for Patch Count
  • Check for Polygon Arrangement
  • Check for Correspondence Control Parameterization