Gulfstream recently issued maintenance and operations letters (MOLS; click link and scroll to bottom of page) regarding ground spoiler checks for GIIB, GIII, GIV, and G450 operators as a result of the ongoing investigation into the December 2021 fatal crash involving a GIV-SP. The twinjet hit the ground during an attempted landing at Las Americas International Airport in Santo Domingo, Dominican Republic, killing all nine on board.
This information “re-emphasizes the critical importance of performing a full verification of spoiler functionality on the ground, as detailed in the respective aircraft flight manual or operation manual.” In addition, the MOLS noted the necessity of adding visually identifiable marks to the hydraulic lines to ensure they are connected to the correct actuator ports.
“Failure to reconnect hydraulic lines to the appropriate actuator ports may result in improper operation of the ground spoilers, including asymmetrical deployment and operation during flight, which could lead to loss of control,” it added.
The preliminary report released by the Dominican Republic CIAA in January noted that both the right ground spoiler and flight spoiler actuators were removed and replaced during maintenance just before the planned flight to Orlando, Florida. The aircraft was seen taxiing for departure with the three spoilers on the right wing still extended. Later, an image of the airplane in flight showed the right-wing spoilers were still extended while the ones on the left wing were not.