Retardation
Unlike contemporary U.S. bombs of similar power it did not use a parachute to retard its fall, instead, the blunt nose was intended to slow the fall of the weapon sufficiently to permit the bomber to escape the detonation, and ensured that Yellow Sun did not encounter the transonic and supersonic shock waves that had caused much difficulty with barometric fusing gates that had plagued an earlier weapon, Blue Danube.
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