Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural MEL / CDL; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Weather / Turbulence
Flight Crew Took Evasive Action; General Maintenance Action
Aircraft; MEL
On initial climb out in moderate turbulence at 280 kts; FO (First Officer) side windshield wiper moved halfway down the windshield into an un-parked position while the wiper switch was selected in the off/park position on both sides. The Captain contacted maintenance who guided us to MEL XX-42-1. After reviewing this MEL we followed the guidance and slowed the aircraft to 250 kts and did not exceed it for the remainder of the flight. We notified dispatch and ATC of our operational restriction and they accommodated us. MEL XX-42-1 is associated with malfunction of the windshield wipers and directs crews to restrict airspeed to 250 kts should a wiper become stuck in an un-parked position. Normal operation in the SOP makes no reference to this limitation (only lists 250 kts as an operational speed) and therefore a pilot would not know about it unless they had experienced this malfunction before. The SOP should be revised to include this limitation so crews are aware of the correct action should this malfunction happen to them in flight.
First Officer reported windshield wiper failed out of park position; causing a reduction in performance penalty that the crew was unaware of.