N555NR

HISTORY OF FLIGHTOn January 2, 2023, about 1135 mountain standard time, an Embraer EMB-505, N555NR, was substantially damaged when it was involved in an accident at the Provo Municipal Airport (PVU), Provo, Utah. The pilot sustained fatal injuries, two passengers sustained serious injuries, and one passenger sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

The airplane’s manager reported that the airplane was in a heated hangar, where the temperature was about 60°, and the ramp area in front of the hangar was heated with radiant heat. He stated that they would typically preflight the airplane inside the hangar, so that the only thing left to do before boarding the airplane was refueling. He spoke with the pilot about 30 minutes before the accident, and they discussed the planned flight to Chino, California, along with the weather and braking action. He recalled that the pilot did ask him about deicing, and he told the pilot that if he needed to deice the airplane, to call the fixed-base operator (FBO). However, their truck was out of service, so he told the pilot to call another FBO if he needed to deice. Personnel from the other FBO reported that while their deice truck was operational, the accident pilot did not contact them on the day of the accident. The airplane manager stated that they only had to deice twice in the previous 8 years.

A witness who was removing snow from the ramp area reported that the airplane was in a hangar near his location and remained there until 1055. The witness stated that he watched the airplane be refueled and estimated that the pilot started the engines around 1110 or 1115, around the same time light snow began to fall, and within a few minutes the snow had covered the areas he plowed.

The fueler stated the airplane was parked in the hangar when he arrived to fuel the aircraft. About 5-10 minutes later, the pilot pulled the airplane out onto the ramp and the fueler repositioned his truck to service the airplane with 350 gallons of Jet-A fuel. The fueler stated while he was completing refueling the airplane, the pilot mentioned that they were trying to get out before the weather. The fueler added that he observed what appeared to be unfrozen water droplets on the wings during the refueling, which he estimated took about 5 minutes.

After refueling the airplane, the fueler returned to the FBO. Upon exiting the fuel truck, he observed the airplane taxi past his location. As he walked toward the FBO, he heard the airplane and turned around to watch it. He stated that the airplane was starting its takeoff roll on runway 13, and appeared to “pull up steep,” roll to the left, and the left wing impacted the ground. The refueler stated that at the time of the accident, the precipitation was snow and a misty rain, with light to medium intensity, along with a light breeze out of the north.

Additional witnesses at the airport observed the airplane takeoff, ascend to about 20 to 30 ft above ground level (agl), and then both wings wobbled “back and forth.” The airplane then banked to right, and then banked “hard left” as the left wing struck the ground.

Review of FDR and CVDR data revealed that at 1118:24, the cockpit area microphone captured the pilot describing to a passenger how to enter the cockpit and where to sit. At 1120:47, the right engine was started, followed by both engine anti-ice switches being commanded on, and the left engine anti-ice commanded off 4 seconds later. The left engine was then started, and its anti-ice was turned back on seconds later. At 1129:, the wing stab anti-ice system was commanded on, and the pilot made the comments “we’re gonna get wing stab arm” followed by “yep, wing stab arm, we got that” followed by the Wing Stab anti-ice switch being commanded off, along with a recorded “click” sound. The Wing Stab anti-ice switch remained off until the end of the recorded data.

The FDR and CVDR captured that at 1130:, the pilot performed an ice condition test and confirmed the ice sensor functioned. About 6 seconds later, the pilot commented “wing stabs gonna be on, on, on, probes are on, engines are on, wing stabs on.” The sound similar to the airplane’s wheels moving over a hard surface was captured at 1130:48.

At 1134:28.5, the pilot briefed the takeoff, and said he was going to perform a static takeoff, commenting that he would “run up the engines with the brakes on and release them so that we have less effect of that slush on the runway.” The left and right engine thrust lever angles along with N1 speeds of both engines increased at 1135:25, followed by the ground speed increasing 7 seconds later.

At 1135:48, the indicated airspeed reached recorded V1 and VR values of 103 knots, which coincided with the pilot’s verbal call outs “there’s vee 1 and rotate.”

Between 1135:50 to 1135:55, the recorded pitch angle started to increase. As the gear weight on wheels indication for the left and right mains transitioned from ‘GND’ to ‘AIR,’ the airplane started a roll to the left, progressively increasing over time, and a stall warning activated at 1135:53.7 before the CVDR stopped recording.

At no time throughout the recorded CVDR audio did the pilot ask others to look at the airplane’s wings or audibly announce he was looking at the wings.

Personnel from Duncan Aviation, one of the two fixed-base operators (FBO) located at the airport, reported that their deice truck was out of service. Personnel from the other FBO reported that while their deice truck was operational, the accident pilot did not contact them on the day of the accident. PERSONNEL INFORMATIONThe pilot held type ratings for CE-500, CE-525S, and EMB-505 airplanes. His most recent recurrent training in the accident make/model airplane was in May 2022. AIRCRAFT INFORMATIONThe airplane was equipped with a Wing and Horizontal Stabilizer Anti-Icing System (locations depicted in figure 1), which was designed to prevent ice formation and remove any ice formed on the leading edges of the wing and the horizontal stabilizer. The system was activated by a 3-position “Wing Stab” switch on the ice protection panel, which is located just below the lower right corner of the left primary flight display.

The switch could be placed in 3 different positions:

ON (up): activated the wing and the horizontal stabilizer anti-ice

systems.

OFF (middle): deactivated the wing and the horizontal stabilizer anti-ice

systems.

ICE SPEED RESET (down): reset the Stall Warning and Protection System (SWPS) to non-icing schedule and removed the SWPS ICE SPEED message.

Figure 1: Airframe Ice and Rain Protection System Deice Systems (Source: Phenom 300 Pilot’s Operating Handbook, Volume 1)

The airplane’s Pilot’s Operating Handbook, Section 2-15, Cold Weather Operation, DEICING/ANTI-ICING FLUID APPLICATION, stated in part:

Airplane surfaces contaminated by ice, frozen precipitation or frost must be deiced before departure. The airplane must be anti-iced when the risk of freezing precipitation exists at dispatch or freezing precipitation is actually taking place. While deicing removes ice, anti-icing protects against additional icing for a certain period of time, called holdover time. A combination of both deicing and anti-icing may be performed based on the judgment of the flight crew and procedures developed by the operator. The choice of the correct method and fluid to be applied must be done according to the weather condition, available equipment, available fluids and the holdover time.

Deicing and anti-icing fluids lower the freezing point of frozen precipitation thus delaying the accumulation of contamination on the airplane. When applied to a clean surface, the fluid forms a thin layer that has a lower freezing point than precipitation. The fluid is highly soluble in water, thus the precipitation or ice melts on contact with the fluid. These fluids also delay the onset of frost on airplane surfaces. As the ice melts, the fluid dilutes with the water, thereby causing the mixture to become less effective or to run off. Ice can begin to form again after enough dilution has occurred and the freezing point begins to rise.

Deicing/anti-icing fluids are not intended to provide icing protection during flight. The fluid must flow off the surface during takeoff. Embraer has performed flight tests to investigate the effects of approved fluids on performance and handling characteristics. The flight tests demonstrated these fluids did not have a measurable effect on takeoff and climb performance.”

The POH continues later in the same section:

The pre-takeoff contamination check is normally accomplished either from inside or outside the airplane within 5 minutes prior to beginning takeoff.

When inspecting the wing, during the pre-takeoff contamination check, look at the entire upper surface and not only at the leading edge or wing tip. Although the wing tips can be seen from the cockpit, almost the entire wing is visible from a cabin window. Therefore, it is strongly advised that the visual inspection be done by a crew member from the cabin. Additionally, the crew should ask for the assistance of trained and qualified personnel outside the airplane to assist in the pre-takeoff and check to make sure that the tail and fuselage, which are not visible from the cockpit or cabin, are free of any ice contamination.

It is the pilot's responsibility to decide whether or not to accept the airplane for flight. If contamination is suspected, the airplane should return for additional deicing or anti-icing. Takeoff in conditions of moderate and heavy freezing rain is not approved.

The POH further stated that “to prevent frozen contamination on airplane surfaces deice and anti- icing operation requires that fluids be distributed uniformly over surfaces. In order to control uniformity, all horizontal surfaces must be visually checked during fluid application. Th...