Lessons Learned From Business Aviation Accidents

NTSB Probable Cause: “The pilot’s conduct of an approach in structural icing conditions without turning on the airplane’s wing and horizontal stabilizer deice system, leading to ice accumulation on those surfaces, and without using the appropriate landing performance speeds for the weather conditions and airplane weight… which together resulted in an aerodynamic stall at an altitude at which a recovery was not possible.”

Several aspects of this accident point to the importance of professionalism when operating an aircraft, especially as a single pilot.

“This pilot was plainly in a hurry, with very little time elapsed between engine start and taking the runway,” said NTSB Office of Aviation Safety Director Tim LeBaron, who served as the Board’s investigator-in-charge (IIC) for this accident. “Throughout our investigation we found several basic things that all pilots should be doing every time they fly, which he simply wasn’t doing.”

While the accident pilot’s failure to engage aircraft deicing systems in snowy conditions may have been an oversight, LeBaron noted the investigation found the pilot had briefly engaged deice earlier in the flight, indicating a possibly deliberate choice to avoid doing so on the approach due to the resulting higher Vref speed when landing on GAI’s 4,200-foot runway.

Mark Larsen, CAM, NBAA director of safety and flight operations, noted similarities to another Phenom 100 landing accident at Berlin, Germany Schonefeld Airport in February 2013, as well as a February 2021 accident at Le Bourget Airport in Paris.

“In its final report on the Paris crash, the French BEA cited essentially identical circumstances to Berlin and Gaithersburg,” he said. “All three accidents appear linked to concerns about the effects from deicing systems on landing performance calculations.”

Following the Gaithersburg accident, the NTSB issued three safety recommendations, including one for NBAA (A-16-014) to work with turbofan aircraft OEMs to develop enhanced training guidelines pertaining to risk management in winter weather operations.

The NTSB noted such guidelines are particularly important for single-pilot operators and in consideration of “pilot performance deficiencies” identified during the accident investigation.

“We found there was very little checking on system knowledge, especially on the recurrent level, and pilots had a lack of understanding of why we do things and why we put procedures in place,” said Daniel Ramirez, who was part of the accident investigation team as a technical advisor from the manufacturer.

NTSB Probable Cause: “The pilot’s failure to release the parking brake before attempting to initiate the takeoff [and] the flight crew’s delayed decision to abort the takeoff. Contributing to the accident was the lack of a NO TAKEOFF annunciation warning that the parking brake was engaged, and lack of a checklist item to ensure the parking brake was fully released immediately before takeoff.”

The presence of more than 6,000 feet of twin tire transfer marks on the taxiway and runway, leading to the burnt wreckage of the Citation Excel, presented NTSB investigators with “a pretty good idea what happened,” noted NTSB investigator and IIC Joshua Cawthra. “After that, our focus turned to the sequence of events that led up to the moment they took the runway.

The NTSB investigation revealed a combination of task saturation, impeded sightlines (that prevented the first officer from seeing the parking brake handle hidden by the captain’s left leg) and lack of redundant procedures and cockpit warning systems to prevent a departure attempt with the parking brake engaged.

While such an accident may seem like an outlier, Cawthra noted such incidents may happen much more often than many might think. “How many times do crews taxi for departure,” he noted, “and set the parking brake so they aren’t holding down the brakes while waiting?

“We can only get so much data on this type of situation, as sometimes the crew catches it,” Cawthra continued. “Of course, they won’t say why they aborted. They simply taxi back, let the brakes cool and then they take off. It’s probably something that happens much more often than we’re aware of.”

NTSB Probable Cause: Not Yet Released

From the Preliminary Report: “Multiple eyewitnesses observed the airplane before the crash. Some reported that the airplane caught their attention because of its low altitude and abnormal flight path into Runway 11.

According to witnesses, the airplane was in a nosedown attitude and steep left turn during its last few seconds of flight.”

Circling approaches represent one of the most challenging operations for business aviation flight crews, in part due to lack of training in real-world scenarios.

Michaela Satter, co-chair of the Loss of Control-Inflight (LOC-I) Working Group to the NBAA Safety Committee, recalled an audience comment from a presentation on this accident that she conducted with fellow working group co-chair Warren Pittorie at the 2022 NBAA Business Aviation Convention & Exhibition (NBAA-BACE).

“This pilot noted they regularly practice circling approaches during recurrent training, but usually at giant airports like New York LaGuardia or Chicago O’Hare,” she said. “There is very little training on real-world scenarios such as going into a high density-altitude airport between mountains after being kept high by ATC until they’re within a few miles of the field.”

The NTSB further noted that the Challenger crew had briefed for a straight-in approach to Runway 11, but ATC routed the flight toward Runway 22 with a circling approach to Runway 11.

“Flight crews must weigh ATC instructions against what you’ve already set up for,” Larsen said. “If that instruction presents significant challenges, you should inform ATC that you are unable to comply with that instruction and consider your options. You can request to fly the approach you’ve mentally prepared for, absent a larger hazard necessitating a change to your plan. As necessary, slow down or take a turn or two in holding to get everything set up and briefed prior to commencing the approach.”

In a March 2023 Safety Alert, the NTSB noted 10 fatal accidents between 2008 and 2023 involving circling approaches. “The [Truckee] flight crew had many options available to them that would have increased the likelihood of executing a stabilized approach and successful landing, such as requesting the approach they originally planned for, briefing the approach they accepted, or performing a missed approach procedure,” the alert stated.

Other non-standard elements to the accident approach were apparent mismanagement of the aircraft’s autothrottles, and deployment of both spoilers and full flaps earlier than normal on the approach.

“Scenarios like this are taught in primary training or toward your commercial pilot certificate,” Pittorie said. “Either we aren’t learning what we need to, or we’re forgetting those lessons. And, it’s all too common in these situations that we find the pilots take shortcuts, or do certain things that are either prohibited or just not recommended.”