Category Archives: Agriculture

A Thrush is “Reborn” with Upgrades & a PT6A-41

It was in 2010 that Thrush Aircraft introduced a new engine mount design for the 510 series Thrush, specifically the then newly certified H80 GE turboprop engine. The extension was approximately 18 inches forward of the hopper, creating a mini-storage area and eliminating the lead-shot ballast ring. Not only did this improve flight characteristics by moving the CG, but removed nearly 300 pounds of “dead” weight.

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The P-750 XSTOL and the P&W PT6-34 Engine

Pacific Aerospace describes its flagship product, the P-750 XSTOL, as the world’s first Extremely Short Take-Off and Landing (XSTOL) aircraft and as the best in the world for the missions it was designed to accomplish. Bold claims from the New Zealand based company, to be sure, but not without foundation, as it can boast some pretty impressive performance. Much of that performance can be credited to the Pratt & Whitney PT6A-34 engine that powers the plane, but more on that in a moment.

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A Look at the PT6A-67F Powered Air Tractor AT-802 Series

When Air Tractor AT-802A, bearing serial #0700 took off last month for its home in Valencia, Spain, the occasion was not just an airplane production milestone. It also happens to be the 25th anniversary year marking FAA Type Certification of the 800-gallon capacity agricultural and firefighting airplane. Jim Hirsch, president of Air Tractor remarked, “It’s been almost 27 years since the first AT-802 test flight over Olney, Texas. The airplane had to overcome some initial hurdles, but the 802 series has become a popular aircraft that is used all over the world for a wide variety of highly specialized applications.” He continued, “Over the years we’ve focused on improving the flying qualities and handling characteristics of the 802 so that it is as enjoyable to fly as our smaller models. This makes for an extremely productive aircraft that keeps pilot fatigue at a minimum—which is another reason for the airplane’s success.”

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Pratt & Whitney Canada’s PT6A-140AG Engine Achieves Seamless Entry Into Service on Air Tractor’s AT-502XP

Marking a successful entry into service (EIS), roughly 25 PT6A-140AG-powered AT-502XP aircraft have been delivered to customers around the world since certification. The EIS of Pratt & Whitney Canada’s latest engine for aerial application aircraft is progressing and as the application season in the Northern Hemisphere winds down, the engine has been performing very well. Pratt & Whitney Canada (P&WC) is a subsidiary of United Technologies Corp. (NYSE:UTX).

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Understanding Fuel Contamination in the PT6A

The customer had sent in an exchange set of fuel nozzles at his normal change interval of 300 hours. The nozzle set appeared to be reasonably typical in appearance; however, every one of the nozzles exhibited streaking during the spray check as received! Nine of the nozzles cleaned up during the cleaning process and spray checked ok. Five nozzle tips had to be replaced to be able to return the set to service. This was unusual for this operator, and he sought for ideas as to what might be the problem.

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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

What Is The True Cost Of A Grounded Agriculture Plane?

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It sure is fun to pull off to the side of the road and watch those agricultural planes do their work. These planes make a sweet sound as they swoop over country roads to spray a field. The lightweight plane is maneuverable and the pilot knows it. Going upside down, twists and turns are all part of the game. But most people don’t understand just how crucial the old “Ag plane” is to the business of farming crops. Continue reading What Is The True Cost Of A Grounded Agriculture Plane?

The History of the Agriculture Plane

Most commonly known as crop dusters, agriculture planes also perform many other functions to assist farmers.  Although most crop dusters are used to spray crops with pesticide, some agriculture planes are used for seeding fields and fertilizing crops as well.  Flying an agricultural plane takes special skills, as these planes usually fly at lower altitudes and must be maneuvered around obstacles as they attempt to keep seeds and chemicals contained to the fields and not on nearby homes or roadways. Covington Aircraft has been offering agricultural plane aircraft engine maintenance in its long history, and we hope you learn a bit from this brief history of agricultural planes.

Curtiss-JN4-Jenny-300x165First Agriculture Planes

The first agriculture plane was not actually a plane at all, but a hot air balloon with mobile tethers.  John Chayton used the device to spread seed over a valley floor in New Zealand that had been swamped in 1906.  In 1921, the U.S. Agriculture Department and the Army Signal Corps joined forces to develop modern crop dusting.  On August 3 of that year, John A Macready piloted a modified Curtiss JN4 Jenny to spread lead arsenate to eliminate catalpa sphinx caterpillars near Troy, Ohio.  The first commercial crop-dusting planes were owned by Daland Crop Dusting, which was co-founded by Lt. Harold R. Harris, a test pilot who flew alongside Macready.

Crop Dusters

Originally, agriculture planes used dry chemicals in order to treat crops, which is how they earned the name “crop dusters.”  Today, the planes use liquid products in order to fertilize or treat fields for pests.  It is estimated that agriculture planes provide up to 25% of the crop production products used in farming.  Because they cover a larger area in a shorter time, crop dusters are the preferred method for farmers who manage large fields.  Because some pests and diseases can cause significant damage in a short period, farmers rely on agriculture planes to control such problems.


In the 1970s, environmental concerns were raised regarding the use of agriculture planes to spread pesticides, which led to more stringent regulations regarding the chemicals that could be used via aerial application.  Agriculture planes and techniques used by pilots have been improved significantly over the past few decades and present day aerial application are considered to be very safe for both people and the environment.

Agriculture planes are a vital part of the farming industry as they control pests, increase crop production and sometimes provide irrigation to areas where rainfall has been less than normal.  For more information on agriculture planes or to learn more about engine repair for your agricultural plane, visit