An improved transmission line or waveguide that can tolerate damage from ordnance fragments without severe degradation of performance. Ordnance fragment penetration into a waveguide tends to produce jagged inward protrusions or loose metal chips of the type which can cause arc-over and high standing wave ratios. The present invention provides a transmission line or waveguide made of a brittle nonconductive material such as plastic or composite material which is coated on the surfaces bordering the interior volume with a solder, conductive paint, or other conductive material. Thus, any penetration of the waveguide will leave a clean hole without jagged protrusions which could precipitate arcing and degrade the waveguide VSWR. An alternative embodiment comprises the construction of the waveguide walls from a brittle conductive material which would leave a clean hole after penetration.
