Texas Turbines Offers ‘Hot Rod’ TPE331Conversions

July 26, 2016 | Author: Bobby Bishop

There are Coke people and Pepsi people. Guys who drive Chevy trucks and Ford enthusiasts. Country music lovers and rock’n’roll fans. I guess you could call me a Honeywell TPE331 turboprop engine fanatic.

It all started about 20 years ago when Texas Turbine Conversions’ sister company Skydive Texas was looking to upgrade the pre-century TPE331-25A engine on our de Havilland DHC-3 Otter. It didn’t take us long to choose the then-Garrett TPE331. In fact, I knew that the TPE331 was the right choice the first time I flew it on a Porter and felt the great power response that this true pilot’s engine delivers. I remember thinking “this is a hot rod engine!”

Until then I only knew the TPE331 by reputation. It had been around a long time and was known for its power, reliability, performance and fuel economy. You might remember that the Porter PC-6 was made famous by Air America during the Vietnam War and all those aircraft were powered by the TPE331 under the harshest conditions imaginable.

As our Skydive Texas’ business grew, we moved up to a de Havilland Single Otter, which we also converted to a TPE331 power plant with great results. The Super Otter is a “work horse” carrying cargo and people in and out of short landing strips.

Then we certified the Supervan 900, which includes both the Caravan 208 and 208B. The engine modification allows the airplane to carry around 18 skydivers in a single-engine airplane which reduces fuel consumption improving the operator’s bottom line – making it a great choice for the industry.

Since it all started, Texas Turbines has sold about 150 TPE331 conversions to skydiving companies, hunting and fishing charters, special missions, passenger operators and private owners. We currently specialize in de Havilland DHC-3 Otter and Cessna 208/208B Caravan conversions.

We do many of the conversions at our Dallas-area facility and we have conversion partners located throughout North America and in Europe, South America, Africa and Australia, too. Let me add that the engine conversions are surprisingly economical with relatively quick return on investment for most operators.

This year the TPE331 celebrates its 50th anniversary. But make no mistake: this is not your father’s turboprop. Honeywell has continuously improved the engine over the years. The TPE331 engine family now includes 18 models and more than 108 configurations. More than 13,000 copies have been delivered and the engine has more than 122 million flight hours under its belt.

I’ve personally flown thousands of hours in airplanes powered by the TPE331 and thousands more in planes equipped with the Pratt & Whitney PT6, the TPE331’s main competitor. For me, at least, there’s just no comparison. But you don’t have to take my word for it – you can check out the online value calculator and compare for yourself. Or you can check our YouTube video that dramatically shows the two engines going head-to-head.

If you fly an Otter or a Caravan and are thinking about an engine upgrade, I’d welcome the opportunity to tell you about Texas Turbines’ conversion program and the Honeywell TPE331. I guarantee you’ll be impressed.

Bobby Bishop

Bobby Bishop is President of Texas Turbine Conversions. He can be reached at bobby@texasturbines.com.

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  • Bob Jackson

    Cost to convert my 1992 C-208B Cost for relish tray,are there any other items that would need to be added. C-GKLR has been running great,pilots love it.