N327FL

On August 5, 2013, at 0848 central daylight time, N327FL, an Embraer S.A. EMB-505, multi-engine turbofan airplane, was substantially damaged during landing at Flying Cloud Airport (FCM), Eden Prairie, Minnesota. The two pilots were not injured. The airplane was registered to and operated by Flight Options, LLC; Cleveland, Ohio. Day visual meteorological conditions (VMC) prevailed at the time of the accident and an instrument flight rules flight plan had been filed for the 14 Code of Federal Regulations Part 91 positioning flight. The airplane had departed Pittsburgh International Airport (PIT), Pittsburgh, Pennsylvania, at 0731 eastern daylight time and was destined for FCM.Both pilots reported that the airplane had been on a fast and steep visual approach when it then landed on runway 10R at FCM. They also reported that the indicated airspeed was about 150 to 160 knots when the airplane touched down on the runway at some point after the 1,000 foot marker. The airplane departed the end of the 5,000 foot long runway and impacted an airport boundary fence and other obstructions before coming to rest upright on a four-lane highway about 1,000 feet from the runway surface. The impact resulted in substantial damage to both wings and the fuselage.

A hand written takeoff and landing data card prepared by the flight crew before their arrival at FCM showed their expected landing weight was 14,000 pounds, their calculated Vref speed was 106 knots, and the Vap speed was 110 knots, with the flaps set at position 3. The airport elevation was noted as 906 feet. The space on the card for runway required was blank and did not have an entry.

Data on page PD35-3 in the Quick Reference Handbook (QRH) showed landing performance for an EMB-505 airplane landing at an airport at an altitude of 1,000 feet at a landing weight of 14,000 pounds, with the flaps set at position 3. When the airplane was flown at a Vref speed of 107 knots and a Vap speed of 110 knots, the expected dry runway unfactored landing distance was 2,378 feet, the expected wet unfactored landing distance was 3,000 feet, and the expected wet factored landing distance was 4,600 feet.

A combination voice and flight data recorder (CVDR) was removed from the wreckage and examined at the NTSB Vehicle Recorder Laboratory, in Washington, D.C. The cockpit voice recorder portion of the CVDR contained 2 hours and 4 minutes of excellent quality voice recordings. A cockpit voice recorder group was convened and a partial transcript was prepared for the last 32 minutes of the flight.

Data from the flight data recorder (FDR) portion of the CVDR recording contained about 107 hours of data. The accident flight was the last flight of the FDR recording and its duration was about 2 hours and 56 minutes, which included the portion of time during the preflight checks before departure from PIT.

An examination of the FDR data showed the following:

At 0846:40 the airplane was on final approach at an altitude of 2,510 feet mean sea level (msl), at an indicated airspeed of 177 knots, and was descending at 3,986 feet per minute. The airplane was then configured with the landing gear extended, the speed brake extended, and the flaps at position 1.

At 0846:40 the recorder values for both engines were about 30 percent N1, and they remained at this level until engine shutdown after the airplane came to rest.

Between 0846:40 and 0847:17 thirteen different aural warning unit (AWU) sounds were announced including multiple calls of: "whoop whoop pull up", "high speed", and "too low. terrain".

At 0847:02 the airplane was on final approach at an indicated airspeed of 186 knots, at an altitude of 1,329 feet msl, or about 423 feet above the airport, and was descending at 3,077 feet per minute.

At 0847:14 the AWU announced "two hundred".

At 0847:16 the flap lever was selected to position 2.

At 0847:18 the AWU announced "one hundred".

At 0847:18 the indicated airspeed was 168 knots and the flap lever was selected to position 3.

At 0847:24 the airplane crossed the runway threshold at an indicated airspeed of 158 knots.

At 0847:28 the airplane touched down on the runway. Indicated airspeed near the point of touchdown was between 145 and 148 knots and groundspeed was between 150 and 153 knots.

At 0847:29 brake pressures for both left and right braking systems began increasing to an initial local maxima of around 630 psi between about five and six seconds after the maximum wheel spin value was recorded. Left and right brake pressure values varied between about 140 and 740 psi until 0847:47.

At 0847:47 there was a recorded brake pedal displacement of about 35 mm of stroke for the right brake pedal and the FDR discrete for brake fail parameter changed to true. Brake pressures then dropped to a value of about 50 psi and remained near that value for the remainder of the recording.

At 0847:50 indicated airspeed was 68 knots when the airplane exited the runway surface.

At 08:48:07 indicated airspeed and groundspeed had become approximately zero knots.

FDR data for the emergency / parking brake lever discrete showed the brake to be on at the start of the flight and was then moved to the release position for taxing during the airplane's departure from PIT. The emergency / parking brake lever remained off for the remainder of the flight and was not activated during the landing at FCM.

Instructions in the QRH for a loss of normal braking on page EAP12-5 showed that when the yellow BRK FAIL message is illuminated the emergency / parking brake lever should be gently applied.

Embraer reported that the brake-by-wire system is designed such that if a failure occurs in either pedal transducer, then the system will declare a brake failure and close the main brake system shut-off valve. The brakes could then be controlled by the emergency brake system using the emergency / park brake handle. There is no anti-skid function when using this emergency brake system.

Recorded data from the brake control unit (BCU) and the FDR indicated that the brakes initially operated normally during the landing roll with the anti-skid operating. During landing, the pedal displacement gradually increased over 17 seconds until the BRK FAIL message illuminated and failure of the normal brake system occurred. The displacement of the right pedal suggests that this failure occurred as a result of over travel of the pedal beyond the mechanical stop.

The recorded data also showed that during the accident landing the emergency / parking brake handle was not actuated and remained at the off position.

Wreckage examination:

A postaccident examination of the engines and the airframe revealed no evidence of mechanical malfunctions or failures that would have precluded normal operation.

The BCU was examined at the manufacturer's facility. The BCU passed a full functional test and it was returned to service.

Airport Information:

The FAA Airport/ Facility Directory, North Central U. S., indicated that FCM was a towered airport with a field elevation of 906 feet mean sea level (msl). The longest runway was 10R-28L, which was an asphalt runway 5,000 feet long by 100 feet wide. Runway 10R was oriented to 098.8 degrees true and 99.9 degrees magnetic. Records show that the asphalt surface was not grooved and did not have a porous friction course overlay.

Meteorological Information:

At 0838 the recorded weather data from FCM revealed that the wind was from 150 degrees at 4 knots, 6 miles visibility in mist, few clouds at 200 feet above ground level (agl), an overcast ceiling at 7,000 feet agl, temperature 18 degrees C, dew point temperature 17 degrees C, with an altimeter setting of 29.89 inches of mercury. Remarks indicated that rain ended at 0819 with a one hour precipitation of 0.01 inches. At 0737 FCM reported that there had been a one hour total of 0.14 inches of rain. At 0653 FCM reported that the daily total rainfall had been 0.81 inches.

At 0847:43 a security camera video frame capture photo showed the aircraft parking ramp adjacent to the runway was wet and there were pools of standing water. Photos of the roadway surface taken between 0857 and 0901 showed the pavement was wet. At 1035 a photo of the runway surface showed the pavement was wet and had several areas of standing water.

Additional Information:

FAA AC 120-108 states "A stabilized approach is a key feature to a safe approach and landing (and is) characterized by maintaining a stable approach speed, descent rate, vertical flight path, and configuration to the landing touchdown point ... at a rate of descent no greater than 1,000 feet per minute (fpm)"

FAA Safety Alert for Operators - SAFO 15009 Date: 8/11/15

Subject: Turbojet Braking Performance on Wet Runways

"Several recent runway landing incidents/accidents have raised concerns with wet runway stopping performance assumptions. Analysis of the stopping data from these incidents/accidents indicates the braking coefficient of friction in each case was significantly lower than expected for a wet runway as defined by the Federal Aviation Administration (FAA) in Federal Air Regulation (FAR) 25.109 and Advisory Circular (AC) 25-7C methods. These incidents/accidents occurred on both grooved and un-grooved or non-Porous Friction Course overlay (PFC) runways. The data indicates that applying a 15 percent safety margin to wet runway time-of-arrival advisory data as, recommended by SAFO 06012, may be inadequate in certain wet runway conditions."

FAA Advisory Circular AC No: 91-79A - Date: 9/17/14

Subject: Mitigating the Risks of a Runway Overrun Upon Landing

Paragraph 6, c, (1): "A 10 percent increase in final approach speed results in a 20 percent increase in landing distance."

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Paragraph 6, j.: "Landing distances in the manufacturer-supplied AFM provide performance in a flight test environment that is not necessarily representative of normal flight operations. For those operators conducting operations in accordance with...