Abstract Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LH 2) or ambient-temperature compressed hydrogen (CH 2). These vessels offer the advantages of LH 2 tanks (low weight and volume), with reduced disadvantages (fuel flexibility, lower energy requirement for hydrogen liquefaction and reduced evaporative losses). The work described here is directed to verify that commercially available pressure vessels can be safely used to store LH 2. The use of commercially available pressure vessels significantly reduces the cost and complexity of the insulated pressure vessel development effort. This paper describes a series of tests that have been done with aluminum-lined, fiber-wrapped vessels to evaluate the damage caused by low temperature operation. All analyses and experiments to date indicate that no significant damage has resulted. Required future tests are described, which will prove that no technical barriers exist to the safe use of aluminum-fiber vessels at cryogenic temperatures.