Our team in Lakeland recently finished a Blackhawk XP67A Engine+ upgrade on a Beechcraft King Air 350. Brochures cover the performance numbers, so this post doesn’t repeat them at length. It walks through what the project involved in our hangar, from ordering the engines to shipping the old ones back, and what we’d tell any King Air owner who’s thinking about the same upgrade.
The Aircraft and the Upgrade
The King Air 350 is one of the most capable turboprops in general aviation, and its owners tend to fly it hard and far. For owners who want more performance at altitude without moving to a different airframe, the Blackhawk XP67A Engine+ upgrade is one of the most significant changes they can make.
The upgrade replaces the factory PT6A-60A engines with new Pratt & Whitney Canada PT6A-67A engines and adds 5-blade composite propellers, all under Blackhawk’s STC. It’s more than an engine swap. The point of the upgrade is to change how the aircraft climbs, cruises, and handles demanding conditions.
What the Upgrade Is Designed to Deliver
Blackhawk publishes these figures for the King Air 350 with XP67A engines:
- Faster cruise: a maximum cruise speed of 343+ KTAS, against roughly 293 KTAS for a stock aircraft at FL280
- Faster climb: up to a 55% reduction in time to climb
- Higher safety margins: more power means better single-engine performance and a higher service ceiling
- More airport options: stronger climb and altitude performance help in hot-and-high conditions
- A quieter cabin: the 5-blade composite propellers run smoother and quieter in the cabin and cockpit
- Engine coverage: a P&WC Enhanced New-Engine Warranty of 2,500 hours or 5 years, prorated to the 3,600-hour TBO
Our job is to make sure the aircraft that rolls out of our hangar delivers on those numbers.
How We Handled the Project, Start to Finish
We managed the project from the engine order through return to service. Here is the work in order.
1. Ordering and coordinating the engines. We ordered the new PT6A-67A engines from Blackhawk Aerospace and coordinated delivery to our facility. Engines are built to order, so we scheduled the hangar slot around their arrival to keep the aircraft’s downtime as short as possible.
2. Removing the original engines. We removed the factory PT6A-60A engines and propellers, then prepared the nacelles and mounts for the new installation.
3. Installing the new engines and propellers. Our technicians installed the PT6A-67A engines and the new 5-blade composite propellers to Blackhawk’s STC drawings.
4. Connections, rigging, and run-up testing. We completed every system connection the installation requires, rigged the engine and propeller controls, and ran the engines on the ground to confirm they were performing as they should.
5. A full Phase 1–4 inspection, at the same time. While the aircraft was in the hangar, we completed Phase 1 through 4 inspections alongside the engine work. With the engines off, we could reach areas that are normally hard to access. Doing both together also meant the owner got the aircraft back with a fresh inspection cycle, instead of scheduling a second visit later.
6. Post-installation inspections and documentation. We inspected the completed installation and documented everything needed for return to service: the STC paperwork, the new engine logbooks, the flight manual supplement, and our own work records. On a King Air, clean records protect the aircraft’s value as much as the work itself does.
7. Returning the cores to Blackhawk. The upgrade works as an exchange, so we prepared the original engines and shipped them back to Blackhawk.
Why Experience on the King Air Matters Here
An STC gives you the drawings. It doesn’t give you familiarity with the airframe. Our team works on King Airs year-round, from progressive phase inspections to landing gear inspections and unscheduled maintenance. That background shaped this project in three concrete ways:
- We combined the upgrade with the inspection cycle. Lining up the Phase 1–4 work with the engine installation made the most of a single hangar visit.
- We managed the logistics end to end. The owner didn’t have to coordinate engine orders, deliveries, or core returns. We handled them.
- We kept the owner informed. Regular updates and photos went to the owner throughout, and those photos are the ones you’re seeing in this post.
“From the day the kit arrived to the day we signed it off, the XP67A Engine+ Upgrade was the most complete package I’ve installed. Everything was there, everything fit, and the documentation was spot on. My team and I couldn’t be happier with how this King Air 300 turned out.”
Mike Naab, Director of Maintenance, Double M Aviation
Thinking About a Blackhawk Upgrade for Your King Air?
Every aircraft and every mission is different. If you’re weighing an engine upgrade, start with these questions:
- Where are your engines in their life? Time remaining to overhaul affects when an upgrade makes the most sense.
- What’s coming up on your inspection schedule? Combining the upgrade with phase inspections can reduce total downtime.
- How do you fly the aircraft? Typical altitudes, mission length, and the airports you use all affect how much you’ll gain.
- Which propeller option fits your operation? Blackhawk offers 5-blade composite propellers from both MT and Hartzell.
- When do you want the aircraft back in service? Engines are built to order, so it pays to plan ahead.
We’re happy to go through your aircraft’s records with you and help you work out whether the upgrade makes sense.
Bring Your King Air to Double M Aviation
We support King Air B200 and B300/350 aircraft well beyond major projects like this one. That includes progressive and phase inspections, turbine engine maintenance, and day-to-day service. To see every model we work on, visit Aircraft We Service. For more on keeping a King Air on schedule, read our guide to King Air maintenance schedules.
Ready to talk about your aircraft? Contact our team or call 863-940-3450 to plan your next project.
