What was found
CREW REPORTED SLAT FAIL WHILE EN ROUTE TO DCA, DECLARED EMERGENCY AND DIVERTED TO IAD AND LANDED WITHOUT INCIDENT. MAINTENANCE WAS DISPATCHED TO THE A/C, TROUBLESHOT AND FOUND RT O/B NR 2 SKEW SENSOR AT FAULT. REPLACED THE RT O/B NR 2 SKEW SENSOR PER EMB AMM. PERFORMED OPS CHECK AND FOUND GOOD PER EMB AMM. A/C WAS RELEASED BACK INTO SERVICE.