Of all the upgrades an owner can make to a Twin Commander, perhaps nothing is more consequential than going from Dash 5 to Dash 10 Honeywell TPE-331 engines. And now the conversion is once again possible, thanks to an exclusive deal between Honeywell and Twin Commander Factory Authorized Service Center National Flight Services.
Long at the top of nearly every owner’s wish list, the Dash 10 upgrade brings numerous benefits, including better performance and lower lifecycle costs. But for years Honeywell priced the conversion so high it didn’t make sense when compared to the overall airframe value. For the past few years National Flight Services, an award-winning Honeywell service center, has been working to try and re-introduce the conversion into the market. It was finally able to ink a deal with Honeywell, and now the Toledo, Ohio-based service center is the only Honeywell-authorized company in the world doing the upgrade.
“I think it’s the best conversion deal that’s been out there since we’ve been working on engines,” said Mike Converse, National Flight’s head of sales.
How it works
In addition to the engines, the upgrade also includes an airframe kit. Although National Flight has the resources to do the entire job, Converse encouraged owners to stay close to home and use their preferred Twin Commander Factory Authorized Service Center as the conduit to the process.
Every independently owned and operated facility has the capabilities to pull the engines, ship them to National Flight for overhaul and conversion, and rehang them. While the engines are going through the conversion, the Service Center can install the airframe kit and be ready to go when the powerplants arrive back at the facility.
Converse stressed that with such reasonable shipping rates and quick transfers, the overall downtime won’t be impacted.
Performance benefits
Twin Commanders are such great performers that it’s hard to imagine a major performance improvement from a more modern engine, but the benefits have been confirmed in testing.
- 160 shp increase per side
- Flat-rated torque to 16,000 feet
- 25-knot increase in cruise speed
- More than 2,800 foot-per-minute climb rate
- 1,833-foot balanced field length
- 7 percent reduction in fuel burn
In addition to performance improvements, the Dash 10 upgrade also provides some financial benefits.
Cost savings
They say there’s no such thing as a free lunch, but the Dash 10 upgrade pays for itself and then some. Let’s start with the cost. Converse said Honeywell is motivated to have owners opt for the upgrade, and National Flight thinks improving legacy airplanes is an important step in ensuring a robust market well into the future. So, the companies have priced the upgrade to be competitive with Dash 5 overhaul prices. Compared to overhauling Dash 5s, the upgrade only adds about $150,000 to the process. That’s not an insignificant investment, but when you compare it to the lifecycle costs, the balance quickly works in favor of the Dash 10s.
It starts with higher overhaul times. Dash 10 engines feature a 5,000 TBO. In addition, there’s only one, relatively inexpensive hot section inspection. In fact, the conversion essentially pays for itself just in the savings on that one inspection. Throw in the fuel savings, a significantly increased airframe value, and it’s clear why the upgrade was so popular when it was first released.
Among the many resources for owners to turn to when shopping for such a large upgrade, there’s no better source of information than other owners who have been through it. Converse is happy to help make connections, as are the folks from any of the Twin Commander Factory Authorized Service Centers.
Converse also mentioned some interest from a fleet operator who currently has a mixed fleet of Dash 5s and Dash 10s. He said the company has seen the lower lifecycle costs of Dash 10s and thinks the upgrade is a good investment. Given that smaller operators, including owner pilots, aren’t in the habit of spending money on questionable upgrades, that’s a positive sign.
National Flight Services has been in business for more than 65 years, and has been working on Honeywell TPE-331 engines for decades. Although the shop offers a full suite of Twin Commander parts and service, it’s most focused on engine repair, inspection, and upgrades. For more information see www.nationalflight.com.
