Don’t Rain on My B-2
The B-2 is in trouble again. In August, a congressional study determined that the bomber's stealth is compromised by rain or even high humidity. Worse, the problem seems impossible to fix. A recent operational evaluation apparently concluded that the bomber's availability was only 22%, and that on average it suffered three losses of stealth per hour—presumably on a clear, dry day.
Rain is a problem because its droplets are detectable by radar. Instead of clinging uniformly to the bomber's special shape, droplets follow lines of turbulent airflow, and the shape they form is definitely non-stealthy. As many airplane passengers have observed, when humidity is high micro-clouds form along lines of air flow, sometimes with dramatic visual consequences. Again, these micro-clouds are visible to radars; after all, that is how weather radars work.