Press Release

The XP67A Engine+ upgrade and seven-blade propeller are now available as a combined performance package for King Air 350s.

Issued by BLR Aerospace.

March 19, 2025

BLR Aerospace, a US developer of performance enhancing products for helicopters and fixed-wing aircraft, is pleased to announce that MT-Propeller Entwicklung GmbH in Atting, Germany has received supplemental type certificate (STC) approval from both the Federal Aviation Administration (FAA) and the European Union Aviation Safety Agency (EASA) for the seven-blade Whisper Prop system, now available for the King Air 300 series aircraft. As co-host of the King Air Gathering 2025 taking place 19 - 22 March in Phoenix, Arizona, BLR will showcase the new propeller, giving attendees a chance to see them in person.

As the worldwide distributor of MT-Propellers on the King Air and Beech 1900 platforms, BLR is excited to offer this advanced propeller option. The new seven-blade Whisper Prop is the quietest propeller available for the King Air 300 series. Its design is built on MT's proven natural composite technology, previously used in the five-blade propeller for the King Air platform. Each blade features a highly developed structural resin-infused wood core wrapped in carbon fibreglass composite skins, ensuring exceptional quietness, durability and efficiency.

“After years of commercial success with the five-blade Whisper Props, we are proud to offer our customers the added option of the extremely quiet seven-blade Whisper Prop,” said Clay Bringhurst, president of BLR Aerospace.

The seven-blade Whisper Prop features an optimised design that significantly reduces noise levels and minimizes vibration, providing King Air 300 series operators and passengers with the quietest, smoothest experience possible.