Measurements of air permeability is a useful both directly, to assess gas phase movement through soils, and indirectly as a proxy for soil hydraulic conductivity. Several designs have been presented for field-based air permeameters. However, none of these designs is suitable for use in rocky soils, such as those that are found in the desert Southwest. We designed an air permeameter that is used with a standard soil corer to facilitate insertion into desert soils. The soil-corer air permeameter (SCAP) design uses digital flow meters together with compressed air tank to measure air flow under low applied gradients. By virtue of its design, SCAP also allows for collection of soil samples for later laboratory analysis, allowing for more direct comparisons of in-situ air permeability with other soil physical and hydraulic properties. Finally, for cohesive soils, the soil sample can be extracted before testing, removing the need for approximate shape factors to account for divergent flow from the base of other designs. We show coupled measurements of in-situ and ex-situ air permeability, soil hydraulic conductivity, particle size distribution, and gravimetric water content measured in four field soils under varying conditions. Results demonstrate the dependence of air permeability on these soil properties and point to possible limitations in the use of approximate shape factors when interpreting air permeameter measurements.