Aeronautical Engineers (AEI) has unveiled plans to launch the first Boeing 737-900 Extended Range Special Freighter (B737-900ERSF), following in the footsteps of the successful 737-800 freighter.
On October 22, 2025, AEI, a passenger-to-freighter (P2F) aircraft conversion specialist, confirmed that the B737-900ERSF program had begun with the goal of introducing the largest narrowbody freighter to its fleet.
Licensed by Boeing as a third-party provider, AEI is aiming to achieve Federal Aviation Administration (FAA) Supplemental Type Certification (STC) in 2029.
This will be followed shortly after by approvals from the European Union Aviation Safety Agency (EASA) and Civil Aviation Administration of China (CAAC).
“This is a strategic move to address the increasing demand for higher capacity narrowbody freighters,” said Robert T. Convey, AEI Senior Vice President of Sales and Marketing. “With the global e-commerce and express markets continuing to grow, the B737-900ERSF will provide operators with the right blend of payload, volume, and economics.”
AEI said that the new freighter will “offer unmatched volume and payload advantages over existing B737 freighter platforms”.
The Boeing 737-900 Extended Range Special Freighter features include:
- Main Deck Payload: up to 57,700 lbs. (26,173 kg)
- Total Cargo Volume: 7,273 cu. ft. (207 m³)
- Up to 12 pallet positions (in 88″x125″ ULD configuration)
- ANCRA cargo loading system
- Seating for five supernumerary passengers (Standard)
- Class E Main Deck compartment with rigid 9G barrier and smoke detection
- Reinforced Floor Structure to support high-density freight and e-commerce packages
- 180-minute ETOPS option available
- Auxiliary Fuel Tank retained for extended range
In 2021, AEI told Air Cargo Management that there could be a future in a Boeing 737-900ER freighter with a potential market of up to 200 aircraft.
According to ch-aviation, current operators of the Boeing 737-900ER include Alaska Airlines, Delta, Turkish Airlines and United Airlines.