CD Aviation Services (CDAS) has acquired Supplemental Type Certificate (STC) SA1024SO, authorizing the installation of Honeywell TPE331-5-252K engines on Twin Commander 690, 690A, and 690B aircraft.
The STC supports aircraft conversions from the TPE331-5-251K configuration to the -252K configuration, incorporating the Woodward fuel system. This expands CDAS’ capability to support Twin Commander operators with a more widely supported and serviceable engine configuration.
The conversion is performed in accordance with Honeywell Service Bulletin SB 72-0216, which enables the transition from Bendix to Woodward fuel control systems as part of the engine configuration upgrade. The STC provides the required airframe approval for installation on the Twin Commander platform.
As operators continue to evaluate long-term support and maintenance considerations, many are moving away from legacy Bendix-based configurations due to decreasing parts availability and limited overhaul support. The -252K configuration offers broader parts availability, expanded overhaul capability, and greater familiarity across the maintenance network.
“This STC provides operators with a clear and practical path forward when evaluating engine upgrades or addressing long-term support concerns,” said CD Aviation Services. “Our focus is on delivering solutions that improve aircraft reliability, maintainability, and overall lifecycle support.”
The STC applies to Twin Commander 690, 690A, and 690B aircraft. Installation availability, scheduling, and program details are available through CD Aviation Services.
Operators interested in learning more about the conversion or planning upcoming maintenance events are encouraged to contact CD Aviation Services for additional information and quoting.
About CD Aviation Services
CD Aviation Services specializes in the maintenance, repair, and overhaul of Honeywell TPE331 engines and GTCP36 APUs, supporting operators across agricultural, business, cargo, and regional aviation markets. With facilities in the United States and Europe, CDAS provides turbine engine support backed by FAA and EASA certifications and more than 30 years of industry experience.