When a first-generation Cirrus SF50 Vision Jet caught on fire while parked at Santa Monica Airport in Southern California on Dec. 27, 2019, it didn’t take long for photos and videos of the burning airplane to appear on social media. Speculation about the cause of the fire spread rapidly but Cirrus cleared up the questions around the accident with a service bulletin issued on February 7. The FAA followed with an emergency airworthiness directive (AD 2020-03-50) on February 14, which calls for compliance with Cirrus SBA5X-23-03.

The Vision Jet was substantially damaged in the fire, but no one was injured. According to the National Transportation Safety Board (NTSB) preliminary report, the pilot noticed “haze in the cabin accompanied by a faint smell of smoke” after entering the cabin and closing the door. “He continued to follow the checklists and after starting the engine, the smoke smell became stronger, and he decided to terminate flight preparations, and have a mechanic examine the airplane.”

The pilot shut the engine down and opened the cabin door. He saw smoke coming from the armrest near the right-center passenger seat. Although a mechanic came with a fire extinguisher, dense smoke poured from the cabin door followed minutes later by flames, “and by 11:55 the cabin was completely engulfed,” according to the NTSB. “The fire department arrived at 12:02, and the fire was extinguished.”

While the Vision Jet remained standing on its landing gear, the cabin was destroyed and the right wing root’s upper skin suffered thermal damage. Damage extended forward from the CAPS parachute enclosure aft to the engine inlet, but the engine and empennage were not damaged.

In a notice sent to customers on February 7, Cirrus explained that the root cause of the fire was “a potential malfunction of the audio interface circuit card, which can result in excessive heat generation. There are 12 of these cards on the SF50, all of which are located in the cabin. These cards provide the audio and microphone functions to the 1/8” (3.5mm) jacks located next to the passenger USB ports in the cabin; note these are not the audio/mic jacks for your aviation headset. This root cause issue will be resolved by removing the 12 circuit cards in the aircraft. We have issued Mandatory Service Bulletin SBA5X-23-03 to resolve this issue and it affects every SF50 in operation.”

According to Cirrus, within seven days of issuing the customer communication and service bulletin, Cirrus’s Assist mobile teams and factory and authorized service centers had brought 97 percent of the more than 170 Vision Jets in the field into compliance with the service bulletin and emergency AD. Cirrus plans to release a new service bulletin to reinstate the functionality of the inflight entertainment system and USB ports this week. Eventually, a new headset amplifier and microphone interface circuit card for the 3.5mm jacks will be made available.