Etihad Airways has finalized engine sale and lease back deals worth $367 million with Mubadala Development Corp.’s Sanad Aero Solutions and Ireland’s Engine Lease Finance Corp. (ELF).

With these agreements Abu Dhabi-based Sanad will purchase and lease back five General Electric GE90 and six Rolls-Royce Trent 500 engines to Etihad, which is also based in Abu Dhabi, while the ELF accord involves six Rolls-Royce Trent 700 and six IAE International V2500 powerplants.

All 23 engines are spares; 16 are already owned by the airline while the remaining seven are future deliveries.

Both transactions are 10-year operating leases.

“These spare engine sales and lease back transactions provide the airline with a long-term financing solution for its entire spare engine fleet while mitigating residual value risk and providing competitive cost of ownership over the long term,” says Etihad President and CEO James Hogan.

Sanad, which was launched in February 2010 by Mubadala with multi-million dollar deals with Etihad and its German partner Air Berlin, says the latest agreement helps cement Abu Dhabi’s aerospace aspirations. “We are excited to expand our relationship with Etihad Airways through this transaction. It is another significant milestone in our shared mandate to establish Abu Dhabi as a global aerospace hub and expands the foundation for further cooperation and partnership between our companies,” says CEO Troy Lambeth.

This is also a follow-on deal for ELF, a Shannon-based company owned by Boston’s BTMU Capital, which itself is a wholly-owned subsidiary of The Bank of Tokyo Mitsubishi UFJ, Ltd.