Designed for stealthy attacks upon particularly important targets, most notably the giant United States Naval Anchorage at Ulithi atoll and the Panama Canal, the 28 Seiran ("Storm from the Clear Sky") were never used, a case of "Too Little Too Late". A brilliant concept, the Seiran was part of a weapons system that required huge submarines to transport them to within range of their target. The I-400 class of sub was capable of carrying and launching three Seirans. The only surviving example of this unusual aircraft is fully restored and displayed at the Udvar Hazy Annex to the U.S. National Air and Space Museum at Dulles International Airport, near Washington, D.C. The Seiran in the illustration is the same Seiran, seen after launch from an I-400 submarine.