Supports the rear wing at the maximum airspeed load case with simplified, separated load paths.
Aluminium swan necks take the drag load, carbon fiber rods resist the lift load, and cables ensure lateral stability. Each member has one job, which is what allows the whole mounting to weigh 0.94 lb.
No part-specific design process is documented. The Rear Wing subsystem design process applies: 1. 2D ANSYS sweeps to optimise element positions and angles of attack for each candidate element count. 2. Verify positions in 3D and increase stack angle of attack where 2D over-predicted. 3. Run integrated half-car runs with the current undertray iteration so element interaction is captured rather than assumed. 4. Full-car yaw runs to check performance when the front stack is reduced. 5. On-track validation with tufting on both surfaces and Flo-Vis oil during constant speed and skid pad.
FEA at 110 mph with a 115 lbf drag load: maximum stress 8.31 ksi, maximum resultant deformation 0.0327 in, factor of safety 4.80. Rod buckling analysed separately.
Swan necks are three-axis CNC milled. Individual member thickness is limited by manufacturability and by handling rather than by stress.
Aluminium swan necks, CFRP rods, steel cables.
CR22 Issue Log, 2024-02-10, Aero. A rear wing cable failed from a bad crimp during a drive day. The cables are what provide the wing's lateral stability, so the failure mode is a loss of lateral constraint rather than a loss of lift reaction. Crimp inspection is now a pre-drive check.
0.94 lb on both CR25 and CR26I. From the cost report drawings and CAD: Dimensions called out on the cost report drawings. These are the figures printed on the drawing, not a labelled specification; open the drawing itself for what each one refers to. CR26E-RW-Swan neck drawing (mm): R6.35, 6.35, 36.87, 694.09 Source: Cost report drawings: CR26E/Aerodynamics/Cost Report & Drawings/Rear Wing/pdfs/CR26E-RW-Swan neck drawing.PDF Quantity per car, as costed: 2
Nothing in CrimsonStorage covers these yet.