Sting (fixture)

The rear end of a sting usually has a conical fairing blending into the (wind tunnel) model support structure.

Critical length of a sting (beyond which its influence on the flow around the model is small) is mostly dependent on Reynolds number.

The part of the sting entering the model is a thin aerodynamically shaped blade so as to minimize disturbance of the flow; see figure.

Stings often attach, at the front end, to internal wind tunnel balances to measure the forces on the model.

Therefore, most stings have a central bore through which the cables from a balance or other in-model instrumentation can be conducted without exposure to the airflow.

AGARD-C standard wind tunnel model on a sting fixture (CAD model)
AGARD-C wind tunnel model on a bent sting (CAD model)
A hypothetical wind tunnel model on a Z-sting (CAD model)
A CAD model of a monolithic internal six-component wind tunnel balance. The tapered rear end of the balance fits into a female taper on a sting (cable for connecting to the data acquisition system not shown); the model attaches to the cylindrical surface at the left side of the balance