The performance of a sequential decoder on data transmitted on a spacecraft link was demonstrated on February 26, 1968, culminating a series of experiments utilizing Lunar Orbiter V and the Deep Space Net (DSN) Echo station. It was demonstrated that sequential decoding can perform on a spacecraftlink as well as was predicted by theoretical results and laboratory experiments. Performance is significantly better than that of practical block codes. For example, an erasure probability of

can be attained using sequential decoding with

dB less signal-to-noise ratio than required to attain an error probability of

using a

biorthogonal code and maximum-likelihood decoding.