From what I was able to find out, he developed three flying boats.
1. MU-3 (SAM-2) - a training flying boat to replace Grigorovich's MU-2. At least one MU-3 was built and test-flown. Unfortunately an illness prevented Moskalev from finishing it and Shavrov's She-2 was adopted instead. Here's the only picture I could find:
2. SAM-11 "Bekas" (Snipe) - a liaison amphibian for the Navy. Again, the prototype was built and tested in 1938 but never adopted because the engine was put out of production.
3. SAM-16 - a short range reconnaissance amphibian. The development was almost completed by 1941 (a scale model was being tested in a wind tunnel) but entering of Soviet Union into WW2 halted the work.
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