Category Archives: Pratt Whitney PT6 Engine

Pratt & Whitney PT6 Celebrates 50 Years Part 2

The 12 engineers who gathered in 1957 to build the first turbine engine for Pratt & Whitney, and who can be considered the brains behind the PT6, created an engine in two sections that are easily separated for maintenance.  The creation of these engineers led to aviation history.

First Flight

beechcraft The PT6 first flew on May 30, 1961 as the power for a Beech 18 aircraft in Ontario, Canada.  Full-scale production began in 1963, and in December of that year, Pratt & Whitney shipped the first PT6 to Beech Aircraft Company to power their Beech 87, an aircraft that later became the King Air.  Experts said that the PT6 was an innovative gas turbine representing significant advances in technology, with great advantages over traditional piston-driven engines.  Much of this benefit was due to the higher power to weight ratio the PT6 offered.

Piper Milestone


In 1967, the Piper PA-31 Navajo first flew using a PT6 engine.  Despite enormous success building light aircraft engines since the 1930’s, Piper fought the adoption of turbine engines in their aircraft.  Instead, they preferred the more traditional piston-driven engines.  This marked an important milestone for Pratt & Whitney who had attempted to get Piper to switch to their turbine engines for many years.

Other Applications

 Although the Pratt & Whitney PT6 became the most popular engine for powering high-performance airplanes and helicopters, in its early days an industrial version known as the ST6 appeared in some interesting applications.  In 1966, the Thunderbird, a 10-meter boat owned by Jim Wynn, a racing-boat champion, used two ST6 engines.  It was one of only two boats out of 31 to complete the Sam Griffith Memorial Race on February 22, 1966, and although it came in first, it was denied official recognition as it was considered experimental.  The turbine engine powered Turbo Train was designed to provide passenger service between New York and Boston, and was supposed to be a centerpiece at Expo 67.  Unfortunately, it was not completed in time for the Expo, but by 1973, was regularly travelling at speeds of nearly 193 km in the Montreal-Toronto corridor.  In 1978, Andy Granatelli, President of STP, installed an ST6 in his custom-made Corvette after it was banned from use in the STP Indy cars by the USAC.

The PT6 not only has a long and colorful history as an aircraft engine, but in powering other types of vehicles as well.  Learn more about the PT6 and find out more about the aircraft maintenance services at Covington Aircraft by contacting them online or by phone today.

PT6 Celebrates Fifty Years Part 1

When it was developed in 1963, the PT6 was the first turboprop engine rated at 450 shaft horsepower, impressing Beechcraft to the point that the company chose to install the engine in their King Air line of turboprop twins.  Fast-forward 50 years, and Beechcraft still choose the PT6, although of ever-increasing power ratings, to power their engines.

 Before The PT6

beechcraftPratt & Whitney began development of the PT6 in the late 1950’s in an attempt to replace the manufacturer’s Wasp radial engines, developed during in the 1930’s.  In 1925, Frederick Rentschler, President of Wright Aeronautical, approached his brother, Gordon, and Edward Deeds, who were both on the board of Niles Bement Pond, convincing them that Pratt & Whitney Machine Tool, a subsidiary of Niles, should fund the creation of a new aircraft engine Rentschler and a colleage, George Mead, were developing.  The engine was to be a large, air-cooled radial design.  The executives at Pratt & Whitney saw an opportunity for growth and lent Rentschler $250,000, the use of the Pratt & Whitney name and space in their building to begin creating the new engine.  Rentschler left Wright Aeronautical and took over operations of Pratt & Whitney Aircraft Division, The first of the Wasp series debuted on December 24, 1925, quickly becoming one of the most widely used aircraft engines in the industry due to their superior speed, rate of climb and reliability.  Charles Lindbergh and Ameila Earhart both set records in Wasp-powered aircraft.

Wasp to Hornet

 With the development of the PT6 still a few decades away, Pratt & Whitney created the next line of radial engines, the Hornet, rated at 525 horsepower.  The dependability of both the Wasp and the Hornet made them very popular among commercial aircraft, and as the public use of air travel increased, so did the demand for Pratt & Whitney engines.  As it became apparent that the United States would enter World War II, President Franklin D. Roosevelt called on manufacturers to produce 50,000 aircraft a year for military use, requiring Pratt & Whitney to expand its workforce from 3,000 to 40,000.  Throughout the war, Pratt & Whitney continued to innovate, until, by the end of the war, their largest engine provided 3,600 horsepower.  However, radial engines were slowly being replaced by lighter turboprop engines.

Vision of the PT6

In 1957, Pratt & Whitney saw an opportunity to channel profits from the piston engine spare parts business to the development of smaller gas turbine engines than those currently being manufactured in the United States. The company gathered a team of 12 young engineers after conducting market studies that found there was a need for a 500 shaft horsepower engine that could replace piston engines, such as the Wasp and Hornet.  In December 1963, Pratt & Whitney shipped the first of the PT6 series, the PT6A-6, a highly innovative gas turbine representing technology advances that were significant at the time.  Because gas turbines have a higher power to weight ratio than piston engines, the PT6 was perfect for aviation engines.

pt6aThe PT6 has enjoyed a rich and colorful history since it began production in 1963, and Pratt & Whitney is proud to celebrate the 50th anniversary of this timeless aircraft engine.  Learn more about the colorful past, pioneers who flew this engine and continuing evolution of an engine ahead of its time.  For more information on the PT6 or about aircraft maintenance, contact Covington Aircraft online or by telephone today.

Aviation Station: Landing Equipment/Landing Gear

landing gear

Pilots use cockpit controls that receive information from the engine, like the PT-6A, for optimum ground handling of turbo prop airplanes. However, without landing equipment and gear, the plane could not be controlled on the ground at all.  Landing equipment and gear are used for takeoff, landing, and taxiing of an airplane.

Conventional Landing Gear

Planes with two wheels forward of the aircraft’s center of gravity are known as conventional landing gear.  Often seen in older aircraft, pilots must brake carefully as, without a wheel at the front of the plane, the turbo prop airplanes pitch easily.  Because the tail is free to move in any direction, planes with conventional landing gear are difficult to control when landing or taking off, even with the cockpit controls found with the PT-6A engine.

Tricycle Landing Gear

Tricycle landing gear looks much like its name indicates, with one wheel on the nose of the plane and two main wheels.  This configuration makes the plane less likely to tip over and easier to handle on the ground.

Tandem Landing Gear

Used for very large aircraft, tandem landing gear has two sets of main landing gear, located one behind the other on the fuselage.  This allows planes with highly flexible wings to be better managed on the ground.  In some cases, small wheels are added to the tips of the wings to keep them from scraping the ground.

Cockpit Controls

Turbo prop airplanes, such as the PT-6A, often have cockpit power-plant controls for greater ground-handling capability.  Although these controls focus on propeller control, the propeller and landing gear often work in tandem, especially during takeoff and landing.   Because landing equipment and gear are a crucial part of the ground operations of any airplane, these cockpit controls found on the PT-6A play an important role in ensuring the safe takeoff and landing of turboprop airplanes.

Visit us at for more information about radial and turbine engines, such as the PT-6A.  Learn more about overhauls, maintenance and repairs, and be sure to find us on Facebook and LinkedIn.

Covington Aircraft PT6 Engine Trainings

Popular Training Highlight:
Pratt and Whitney PT6 Engine Series

At CovingtonAircraft, we have a variety of customers come in and ask us about the different PT6 Engine training opportunities we provide. We realize that not everyone knows we provide trainings and that we do more than aircraft overhaul and maintenance. We asked our Executive Vice President at Covington Aircraft, Aaron Abbott, about what makes us special when it comes to trainings and this is what he said.


What is our most popular training at Covington?

Aaron: “Our most popular training is centered around the PT6A engine series.  We have pilots and mechanics looking for PT6A Pilot Familiarization as well as Line Maintenance training.”

How much do the trainings cost?

Aaron: “Our trainings can be an extensive process, but it also meets a customer need, so we provide it as an added value service to our clients for FREE. We do offer some charged-based training, but it’s generally just to cover costs associated with different catering, materials or something along those lines.”

What is the farthest distance someone has traveled for a training?

Aaron: “We have people come to us on a regular basis from all across the states as well as from Central and South America.  We will also work with customers in order to set up and conduct trainings at their facilities around the world.”

At Covington Aircraft, we do our best to provide the types of training clients need, and we’re happy to help anyone who wants to learn safety and the art of maintaining an aircraft.

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