Tag Archives: PT6A

The PT6A – The Legend Tells Its Story


It’s the remarkable story of a remarkable engine. With more than 51,000 engines delivered to power some 130 different applications, the PT6 engine can tell quite a story of creativity and transformation. While we had a lot to choose from, we’ve put together a list of milestones for the engine as we mark its golden anniversary.

1957 – P&WC assembled a team of 12 talented young engineers after studies showed a market opportunity for 500 shp (shaft horsepower) class turboprop engines in the aircraft market then powered by piston engines. P&WC saw an opportunity to channel some of the profits from its piston engine spare parts business towards the development of gas turbine engines smaller than those made by its U.S. parent.

Twelve key men on the PT6 engine design team: Gordon Hardy, Jim Rankin, Fernand Desrochers, Fred Glasspoole, Ken Elsworth, Allan Newland, Pete Peterson, Hugh Langshur, Jean-Pierre Beauregard, Elvie Smith, Dick Guthrie and Thor Stephenson.

Twelve key men on the PT6 engine design team: Gordon Hardy, Jim Rankin, Fernand Desrochers, Fred Glasspoole, Ken Elsworth, Allan Newland, Pete Peterson, Hugh Langshur, Jean-Pierre Beauregard, Elvie Smith, Dick Guthrie and Thor Stephenson. © Library and Archives Canada. Reproduced with the permission of Library and Archives Canada. Source: Library and Archives Canada/Credit: Bruce Moss/Weekend Magazine collection/PA-167966.

1963 – It’s what our celebration is all about. In December 1963, P&WC shipped the first PT6 production engine, the PT6A-6, to Beech Aircraft Company for its Beech 87, which later became the King Air. The PT6A-6 was a highly innovative gas turbine that represented a significant advance in technology from the traditional piston-driven engines used to power small aircraft.  Gas turbines have a higher power to weight ratio than piston engines.

The first PT6 production engine.

The first PT6 production engine. P&WC Archives (Records and Information Management).

1967 – Piper’s PA-31 Navajo took its first flight powered by PT6A-20s. Piper had enjoyed enormous success building light aircraft since the 1930s, but it took P&WC years of effort to get Piper to adopt turbine engines and move away from their traditional reliance on piston-driven engines.

1968 – P&WC’s ST6L73 engine (a derivative of the PT6A without the gearbox second stage) entered into service as an auxiliary power unit (APU) for the Lockheed L1011 airliner.

1968 – Bell Helicopter placed its initial order for P&WC’s first turboshaft, the PT6T Twin-Pac® engine

1970 – P&WC’s PT6T Twin Pac® entered into service. It is two engines coupled in a single package to power medium-sized, twin-engine helicopters.

1970 – The United States Military ordered 294 Bell 212s under the designation UH-1N equipped with PT6T Twin-Pac® turboshaft engines. Delivery also began in 1970.

1973 – The second-stage power turbine was introduced on the PT6A-41. This was a step change in engine power and efficiency.

1979 – An Air Tractor agricultural aircraft is powered by a PT6A engine and flies to the National Agricultural Aviation Association convention in Las Vegas – the first time such a combination was displayed in public.

5 Quick Tips For Servicing Your Engine’s Oil System

This article originally appeared on the P&WC Airtime Blog.

Our expert shares 5 oil maintenance best practices that will help give you a clear picture of your oil status and keep your engine performing optimally.


If your engine oil is at a level below the minimum, the oil supply during operation may be insufficient. Conversely, a level that exceeds the maximum may impede proper operation of the air/oil separator or breather, leading to possible bearing seal distress and loss of oil through the engine breather tube.

An oil level that’s too high or too low could also result in oil pressure fluctuations, low-pressure indications and engine damage.


To perform engine oil system servicing effectively, you should continuously monitor your oil consumption. Careful monitoring will give you advance warning of abnormal oil consumption allowing you to carry out preventive troubleshooting.


For more accurate results, we recommend recording oil consumption data over at least 10 hours of accumulated flight time and plotting the data for oil consumption trend analysis. This will give you a more realistic portrait of your engine’s functioning.

On a related note, be wary of oil level readings taken when the aircraft is parked on uneven ground, since they may not be accurate.

Aircraft attitude may affect engine oil level readings, especially in the case of helicopters, which land on all kinds of uneven surfaces. You shouldn’t use readings taken when the aircraft is resting at an angle.



Always check and service your engine oil system at the same time, based on the instructions in the engine maintenance manual. Typically, the designated time is around 15 to 30 minutes after shutdown. This is fundamental to obtaining reliable and accurate oil consumption trend data. If you wait longer than the indicated time to check the oil level, it may affect the readings, since hot oil in a still-warm engine has more volume than cold oil.

Checking the level as recommended by the engine maintenance manual can also help you identify issues. For instance, if you checked the oil level shortly after shutdown, then come back the next morning and notice that it’s notably lower, internal static oil transfer may have occurred overnight.

In a situation like this, do not simply refill the oil tank. If you do, there may be too much oil in the system and it could overflow via the engine breather. Perform troubleshooting instead to resolve the matter. On a PT6A engine, the cause could be a leaky oil filter check valve.


Likewise, you should always service your oil system to the same level. If you fill the oil tank to the maximum one day and to the minimum the next, it could skew your data. No matter what the oil level indicator configuration is, we recommend always servicing your engine oil system to a level somewhere between the minimum and maximum.

If you keep your oil levels at the maximum all the time, it could increase your oil consumption rate, since some oil has a tendency to exit through the engine breather. This could even happen at one or two quarts below the maximum, so you should adjust accordingly and service the oil system to a level where consumption is acceptable.



When topping up your engine oil tank, be sure to use an appropriate filling device such as a funnel or fluid servicing cart with the appropriate attachment. Using the wrong device could lead to spills and leakages, as well as an inaccurate oil usage recording.

You should also exercise caution when inter-mixing different brands or types of oil and always follow the recommendations in the applicable engine maintenance manual and oil service bulletin. When permitted, switching to another kind of oil might require additional maintenance, such as oil analysis and filter inspection, paying attention to carbon deposits. As different oils may have different properties. And in some situations, such as engines that have accumulated a lot of hours, switching oil type may be prohibited.

The best thing you can do is to stick with the same brand and type of oil. If you have to change, always check the applicable engine maintenance manual and oil service bulletin first to see whether you can and what oil brands and types are acceptable.


Putting these handy tips into practice while also following the standard procedures in your maintenance manual will allow you to maintain a normal main oil pressure during engine oil system servicing.

With the help of P&WC’s new Oil Analysis Technology –which is 100 times more sensitive than other oil monitoring technologies on the market –your engine oil can also provide you with insights into the health of bearings, gears, carbon seals and other engine parts. By analyzing data taken from periodically collected oil samples, this technology monitors engine health on wing and supports predictive and preventive maintenance without intrusive inspections. To learn more, check out Oil Analysis Technology Makes Proactive Maintenance Easier.

pt6-a engine

Pratt & Whitney Canada Innovates Pay-Per-Hour Maintenance with the Launch of New Coverage Program

ESP®ecially for Your PT6 engine and new engine ESP plans: Enrolling today

ORLANDO, FLORIDA–(Marketwired – Oct. 27, 2016) – With more than 10,000 engines already enrolled in its pay-per-hour maintenance plans, Pratt & Whitney Canada (P&WC) is once again raising the bar with the introduction of a leading-edge Eagle Service Plan™ (ESP) maintenance program tailored to PT6A customers, as well as a major enhancement to its current ESP plan offering. Each maintenance plan optimizes aircraft availability and performance while protecting and enhancing the value of the aircraft investment. P&WC is a subsidiary of United Technologies Corp. (NYSE:UTX).

The ESP plan is a simple, cost-effective pay-per-hour engine coverage program that provides long-term costs and ensures a planned and preventative approach to maintenance. Being launched are: ESPecially for Your PT6 engine, which provides the first 400 hours of coverage for free to customers of new PT6A engine-powered aircraft; and an enhancement to P&WC’s current ESP plan offering, which enables customers to apply their ESP plan investment toward a new engine of the same model or a new engine conversion at time of overhaul.

“We continue to push ourselves to think outside of the box – about how we best serve our customers as well as deliver the greatest value and return on investment,” said Satheeshkumar Kumarasingam, Vice President of Commercial Services. “We’ve proven the bottom-line value of the ESP plan to thousands of customers as a unique solution that delivers a planned approach to OEM-backed engine maintenance. And we continue to innovate our maintenance coverage options with the launch of new and enhanced programs. Today’s announcement is a testament to the program’s ongoing evolution in delivering comprehensive pay-per-hour coverage.”

ESPecially for Your PT6 engine plan: First 400-hours of coverage at no cost

This past July, P&WC introduced the ESPecially for Your PT6 engine plan to aircraft OEMs as a way to support new aircraft sales and deliver optimal value to customers of new PT6A engine-powered aircraft. The plan includes P&WC’s world class ESP program with the first 400 hours of engine coverage at no cost to customers, representing a value of up to $50,000 per engine toward future maintenance. Additionally, after the first 400 hours of no-cost coverage customers will receive a reduced ESP plan rate until their first overhaul.

kodiak pt6a

“In three months since we launched ESPecially for Your PT6 engine plan, the enrollment in the program has been outstanding,” said Kumarasingam. “With the PT6A engine, we’re delivering innovative hardware and responsive care – . In fact, we’re seeing interest from aircraft OEMs to incorporate ESPecially for Your PT6 engine plan into their own maintenance packages to offer the most comprehensive ‘tip-to-tail’ aircraft coverage.”

New Engine ESP Plan Option: Apply your ESP investment toward a new engine or new engine conversion at Time of Overhaul

For customers already enrolled in an ESP plan and contributing on a per-flying-hour basis, P&WC has enhanced the plan to allow customers to select a new engine of the same model or a new engine conversion upgrade at time of overhaul for an additional cost.

“Exceptionally simple and flexible, this ESP plan enhancement is applicable on all active P&WC engine programs and gives our customers the ability to choose how their investment in ESP pay-per-hour plan coverage is applied at the time of overhaul,” continued Kumarasingam. “In addition to a higher residual value and/or a performance upgrade, customers will have all of the advantages that come with a new engine – from first run warranty and a parts service policy in full, to improved aircraft resale value.”

About the Eagle Service Plan

Simple to use yet comprehensive, P&WC’s ESP plan is an engine maintenance service plan for which operators pay a fixed monthly fee based on engine hours flown. For all ESP programs, plan members simply select the level of coverage that best fits their operation and pay an hourly rate based on the number of hours flown each month. All coverage levels include:

  • Engine overhaul/refurbishment
  • Hot Section Inspection/refurbishment
  • Basic unscheduled engine maintenance
  • Basic unscheduled accessories repair
  • Recommended product support improvements at engine shop visits
  • Rental engine support

Visit us at NBAA BACE, booth 3239. Interested operators customers are invited to stop by the P&WC booth to speak with a customer service representative.

About Pratt & Whitney Canada

Founded in 1928, and a global leader in aerospace, P&WC is shaping the future of aviation with dependable, high-technology engines. Based in Longueuil, Quebec (Canada), P&WC is a wholly owned subsidiary of United Technologies Corp. based in Farmington, Connecticut, provides high-technology systems and services to the global aerospace and building systems industries.

Agricultural Planes & Turbine Aircraft Engines: A Match Made In Heaven

Af Planes and Turbine EnginesAgriculture planes are an integral part of the United States. The country has moved toward growing massive amounts of food per farm all across the country. These plots of land need to be seeded, fertilized and sprayed with pesticide in order for the farm to make food for the masses. The upkeep of huge plots of farm land can cost tens of thousands of dollars per year. As farmers and agricultural businesses try to turn a profit, they look for more creative ways to save money on the upkeep of their land. Continue reading Agricultural Planes & Turbine Aircraft Engines: A Match Made In Heaven

PT6 Celebrates Fifty Years Part 3

The PT6 engine from Pratt & Whitney was innovative, and has been a mainstay in small aircraft production for 50 years.  The engine could not have happened without the dedicated and talented team of 12 engineers, now known as the “PT6 Pioneers,” who created and developed the engine into the powerhouse that it is today.  One of those pioneers, Gordon Hardy, recently spoke to PT6 Nation about the historic creation of Pratt & Whitney’s first turbine engine.

Paper Sketches

A tour of Mr. Hardy’s home reveals displayed sketches of the PT6 when it was simply an idea on paper, and the faded ink demonstrates a time when technology used to design engines did not exist.   Today, engine parts are designed digitally from the casting process through to the final inspection.  The sketches Mr. Hardy has on display show how far the PT6 has come over the years.  Mr. Hardy credits his wife with being a huge support for him through the process as the early days required him to work long hours, keeping him away from the family for extended periods.  Mr. Hardy and his wife, Margaret, came to Quebec, Canada from England in 1957 to work as a designer at United Technologies.  He  joined the P6 Pioneers in 1963.

Our Baby

Mr. Hardy says that in the early development of the PT6, the engineers discovered here was a gap in the power range between 400 and 2,000 where there were not too many turbine engines available.  The engineers looked at the Beaver aircraft and determined that type aircraft that could benefit from a good turbine engine.  He says that it turned out to be the perfect type of engine for that aircraft.

Fundamental Architecture

Historic scan pt6 engine applicationThe center mounts on the engine enable fast removal of the power section, which enables inspections to be performed more easily.  The unique design of the engine allows maintenance to be performed both on and off the aircraft, making maintenance and repairs much easier.  When the PT6 was developed,  there was a fixed shaft engine available, but it had features that were not as appealing, according to Mr. Hardy.  Handling with fixed shaft engines was compromised as was the speed range, and the PT6 Pioneers realized that with a free shaft turbine, sections of the engine could be separated to provide better handling and speed.  This provided excellent flexibility over other engines.  The reverse-flow of the engine also allowed for a much quieter engine and was less susceptible to damage from birds or other debris.

Gordon Hardy, one of the PT6 Pioneers, made history when he assisted in the development of the historic Pratt & Whitney PT6 engine.  In the final part of this four part series, Covington Aircraft  talks about the innovation in an engine that was ahead of its time.  For more information about the PT6 or about aircraft maintenance services, visit Covington Aircraft online or contact us by telephone today.

Covington Aircraft: Internationally certified destination for Aircraft Engine Overhauls

Did you know that Covington Aircraft is internationally certified for maintenance, repair, and overhaul of PT6A turbine engines and R-985 and R1340 radial engines?

David Hamilton, aviation expert, is here for your needs and explains our global reach!

We’re excited about providing service to our customers here at home and worldwide in the Global Aircraft Community!

Covington Aircraft helps customers worldwide so no matter where you are, we can take care of you.  Whether your engine is being overhauled in our state-of-the-art Pratt &Whitney Canada approved facility, or we are coming to work at your location, Covington is your Global Aviation partner.

Call us from anywhere in the world or visit us on the web at covingtonaircraft.com

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Global Turbine & Radial Aircraft Engine Sales and Overhaul Company has long Local History

Find our more about Covington Aircraft at www.covingtonaircraft.com

It’s pretty cool to say you work for an aircraft company.  Hi everyone, I’m Aaron Abbott and I’m proud to say that I work for a company that has been around for almost 40 years.  When Covington Aircraft first started, it began working on the Pratt & Whitney R-985 and R-1340 radial engines as a way to take care of the air cargo industry.

Now, Covington Aircraft is one of the few OEM authorized MRO facilities in the world.  Still true to our beginnings we continue to overhaul and maintain the radial engines, but in the mid 90’s we added the Pratt & Whitney Canada PT6a series engines to our list of capabilities.  This allows us the ability to take care of the corporate and agricultural markets in a more effective way.

Covington Aircraft is not just a company that specializes in the overhaul and maintenance of aircraft engines, but also sets an example for other companies with its tried and true dedication to being a company entrenched in integrity.  Our word is our bond.  It is our goal as a company to provide the customer with dependable service, at affordable prices, and it is our commitment to do this with exceptional service.

We’re among the world’s leading maintenance, repair, and overhaul facilities, specializing in the PT6A turbine and R-985 and R-1340 radial engines and accessories.  And we are proud to offer the fastest turnaround time and lowest prices in the business.

We also offer 24 hour worldwide aircraft on ground support.

Feel free to contact us today at covingtonaircraft.com

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Aviation Engine Service Expert: David Hamilton

A discussion with an expert in airplane overhaul and maintenance and aviation engine service

IMG_60232David Hamilton knows a thing or two about aircraft repair.  As a teenager, he began working for Covington Aircraft part-time, helping them with their aircraft engine overhaul and aviation engine service business.  Now, over 25 years later, David is the Vice President and Operations Manager of the Covington Aircraft Engines Turbine Division.  But he isn’t focused on the past; he’s focused on the future of airplane maintenance, repair and overhaul.  Here’s an interview with David himself:

Walk us through a typical day.  What does your job entail now, and how has it changed from when you started?

David: “I started working part-time on overhauled aircraft engines when I was 15.  Covington is the only place I have ever worked.  Now, my job consists of organization of personnel, materials, facilities and parts to supply the needs and requirements of our customers’ work orders. I coordinate jobs through our facility for those same customers. I arrange purchases and sales of engines for our facility, coordinating exchanges, overhauls and repairs to meet any changing needs our customers may have.”

Where do you see Covington Aircraft going in the next 5 years?

David: “I see us growing in the PT6A market, as our relationships expand in the corporate and military markets. I also believe we will continue to be a leader within the AG market, supporting our faithful customer base. As the AG market moves more toward larger engines, I believe we will become the premier overhaul and maintenance shop to meet their needs. We owe the AG market a lot, not just in our customer’s faithfulness but for the lessons that will serve us well as we go after new business outside that market. We have a strong desire to grow, but not at the cost of our current customer base.

Being very customer-oriented, I believe the lessons we have learned in the AG market, concerning AOG situations and personal attention to individuals, are exactly what the Corporate and Military Markets are looking for. We intend to meet and exceed those expectations.”

For more information on David and the rest of the Covington Aircraft crew, visit our website or stop into our facility and learn more about commercial aircraft maintenance and overhauled aircraft engines.

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