Low-Intrusive Fiber Optic Plug for TPS Materials (FiberPlug)

Table of Contents

Motivation

Prior flight systems for ablative Thermal Protection System (TPS) spectroscopy (Fire II) used a complex system of multiple windows to provide an optical path that was protected from reentry heating. Due to the weight and complexity of this system, this approach has not been retried on any flight system reentering at orbital velocities (>8 km/s).
The Fiberplug concept embeds optical sapphire fibers in a stepwise fashion below the surface of a “plug” of ablative material within the ablative TPS. As the TPS burns off, new fibers are exposed. All the while, spectroscopic data is being recorded by the spectrometer.

Plasma layer formation analysis and modeling.
EDA is currently designing and optimizing a fiber optic plug and simulating hypersonic reentry conditions in the plume of a 80kw plasma arc jet.

EDA is working with Reentry Plasma Experts by supporting their Computer Models with experimental data from EDA’s 60kW arc-jet vacuum-facility. Working with various ablators and sappire fiber optics, EDA is gathering experimental evidence to support Models as needed.