The GBU-54 is identical to which bomb except for an added DSU-38 laser sensor?

The GBU-54 is specifically designed to enhance precision targeting capabilities by incorporating the DSU-38 laser sensor. This addition allows the GBU-54 to utilize both GPS and laser guidance for improved accuracy against moving or stationary targets. The GBU-38, which is based on the 500-pound class warhead, serves as the foundation for the GBU-54. The GBU-38 is an GPS-guided munition that is smart and versatile, making it the closest match to the GBU-54 in terms of weight and basic design.

The integration of the DSU-38 sensor into the GBU-54 differentiates it from the GBU-38 while still maintaining the overall structure and performance characteristics of the GBU-38, which is why the GBU-54 is considered virtually identical to it, apart from the added sensor. This makes the GBU-38 the correct reference point for understanding the GBU-54's design and capabilities.