Date: 201412
Local time of day: 1201-1800
Location: IAD.Airport, DC
Flight conditions: VMC
Weather elements / visibility: Rain
Light: Daylight
Aircraft: Embraer Phenom 300
Operator: Fractional
Operating under: Part 91
Flight plan: IFR
Mission: Passenger
Flight phase: Landing
ATC / advisory: Tower IAD
Aircraft component: Normal Brake System
Component problem: Design; Malfunctioning
Reporter organization: Fractional
Reporter function: First Officer; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Confusion; Human-Machine Interface
Anomaly: Aircraft Equipment Problem Less Severe; Ground Event / Encounter Other / Unknown
Detector: Person Flight Crew
When detected: In-flight
Result: Aircraft Equipment Problem Dissipated; General Maintenance Action
Contributing factors: Aircraft; Weather; Human Factors
Primary problem: Ambiguous

Narrative: I was the pilot flying. Runway 19L at IAD is grooved; but the runway was wet from recent showers. The temperature was warm enough that there was no chance of ice. The wind was light; around 5 knots; and mostly down the runway. When the airplane touched down; I applied the brakes firmly; but not excessively hard. The airplane continued straight down the center line of the runway; but slid somewhat 'sideways;' with the nose and tail maybe 20 degrees off center. (The nose was to the right of the center line) I let off of the brakes and steered the plane back straight; allowed it to slow naturally a few seconds and then re-applied the brakes and slowed it down to exit the runway normally. During this event; I did not feel any type of pulse from the brake pedals; like you often do when the anti-skid system activates. I believe that the airplane was either 'hydro-planning' or that the brake-by-wire system was not working effectively. I have over 450 hours in this type of airplane and 150+ landings; and have never before felt the sensation of 'sliding;' even when landing on runways contaminated with snow. We wrote the brake system up to be inspected for proper operation and no defects were found. We flew the same plane after it was released from maintenance; and it seemed to brake normally on subsequent landings.There have been several Embraer Phenomenon incidents where the airplanes have gone off of 'wet' runways. I do not know if the problem lies within the braking system; the tires; or something environmental like the white painted markings on the runways themselves; but special caution needs to be taken when landing on a 'wet' runway; even if the runway is 'grooved.' This aircraft type is capable of landing and stopping on short runways under 'dry' conditions; but the estimates for landing roll on 'wet' or 'contaminated' runways may not be conservative enough. I submit this report only to share my experience in hopes that we can find a common link with other incidents; and make the operation of these airplanes safer for all of us.




Synopsis: EMB300 First Officer experiences a brake malfunction during landing on a wet grooved runway. The aircraft yawing 20 degrees right; but the aircraft continuing down the centerline. The brakes are released and reapplied and braking appears normal. Maintenance is advised but no faults can be detected.