Thrush 510G

With each pass, Thrush test pilot Terry Humphrey would put the airplane into a 60-degree climbing turn, unload the wing and slice an arc back toward the tree line, barely avoiding the pines before aggressively jabbing forward on the stick to get us back down on the deck — the sprayers coming on — as we’d tear across the field in the opposite direction.

Our airplane's 800 s­hp General Electric H80 turbine engine did easy work as the speed again increased to 145 mph. Then we were pointing skyward once more, sprayers off, slicing another arc up and over and back toward the field to hit a corner we'd missed. The nose of the Thrush 510G agplane pointed sharply at the earth on the return path, ­little other than the dusty ground and lush, leafy rows of peanut plants visible until, mercifully, the nose came up, the wings leveled and, with an almost imperceptible pop, the sprayers came back on for another pass.

Throughout this dizzying roller-coaster ride, Humphrey deftly handled the controls in the front seat while I observed from the back, bracing myself for something bad that might happen at any moment as we barely cleared the trees or dove back toward the ground at angles reserved for hard-core aerobatics, dogfighting and, of course, “aerial application” — what most people think of as crop-dusting, and a misnomer since the majority of spraying done nowadays is with liquid insecticides, fungicides and fertilizers rather than the powdered chemicals commonly used in the past.

Rebirth of a Brand
The Thrush 510G is the latest product from Thrush Aircraft, the Albany, Georgia, maker of spray agplanes reborn under new ownership a decade ago. Amazingly, the Thrush model we flew traces its roots to 1956, when aircraft designer Leland Snow built the prototype of what would become the Snow S-2 crop-duster. The Aero Commander division of Rockwell International bought the design in 1965 and built a factory at the Albany airport five years later to produce the airplane. The name changed to the Rockwell Thrush, and then again to the Ayres Thrush when Fred Ayres, a top Rockwell International dealer and airplane designer in his own right, bought the company in 1977. Snow had designed the original airplane with an open cockpit and 450-horsepower Pratt & Whitney R-985 radial engine. Rockwell substantially redesigned and improved the S-2, flying it for the first time in 1966 and fitting it with the more powerful Wright R-1300 Cyclone seven-cylinder radial engine.

In 2003, Georgia businessman Payne Hughes bought the struggling Ayres operation and renamed it Thrush Aircraft. He has spent a good deal of money since then upgrading the factory and improving the Pratt & Whitney PT6-powered 510P, 550P and 710P (the numbers represent the total gallons the airplanes’ hoppers can accommodate).

The company’s most ambitious plans to date are revolving around the certification effort for the GE-powered 510G, an airplane featuring far more than a different engine under the cowl.

Here again, designers took a proven product and upgraded it with more power and a long list of other changes, including a welded steel frame that is powder-coated externally and oiled internally for exceptional corrosion protection. Hughes also directed his engineers to redesign everything forward of the firewall, a change that provides lots of extra space for the pilot’s overnight bags plus avionics and allowed Thrush to remove 250 pounds of ballast required in the 510P model.

The GE H80 engine began life as the Walter 601M, first run in 1967 by Walter Aircraft of the Czech Republic. It delivers 50 more horsepower than the available PT6-34AG in the Thrush 510P, while also burning less fuel. GE gained certification of the H80 in March, and Thrush has been test-­flying the 510G ever since as the company awaits the final FAA sign-offs needed to start selling the new model.

I had the chance to visit the Thrush factory in July and came away impressed by the company and its products. Although the factory itself is more than 40 years old, it’s a first-rate operation that I was surprised to find buzzing with activity. Thrush will build more than 50 airplanes this year, the highest production rate since the boom times in the 1970s and huge improvement over recent years, when sales slowed to a trickle.

The Thrush product family has gained footholds in more than 80 countries and is used today for spraying all sorts of crops, from wheat, cotton and peanuts to bananas, rice and just about anything else you can think of. Thrush agplanes are used by some of the biggest names in agriculture, including Del Monte and Dole, and even for drug eradication by the U.S. State Department in South America. (Humphrey knows all about this sort of operation too — flying for the State Department a few years back, he was shot down by a shoulder-fired rocket while spraying a coca field with herbicides in Colombia. He showed me pictures of other agplanes he flew that came home riddled with bullet holes.)

The Big Business of Ag Spraying
For me, one of the biggest surprises after visiting Thrush was learning just how sophisticated the aerial application business has become over the years. The image of the ag pilot as popularized in American movies is of a rough-around-the-edges loner who gets cheap thrills from taking risks. Now, it's probably true that your average ag pilot isn't going to be as polished as, say, the crew of a Gulfstream G550 at a Fortune 500 company, but still, he's probably just as smart — and is almost certainly a better pure stick-and-­rudder pilot.

He might even be better paid. New ag pilots fresh out of flight school earn $40,000 to $50,000 a year, but experienced pilots can make more than $100,000 and the top earners can pull in more than $200,000 a year. As is the case with many flying jobs, how much a pilot makes depends on how much he flies. Aerial application generally pays by the acre, with a pilot typically receiving a cut of perhaps 20 percent. So, for example, if a farmer pays $6 an acre for spraying, the pilot’s one-fifth share would be $1.20. An ag pilot’s day can last 12 or 14 hours, and the acreage can quickly pile up.

It’s no wonder that pilots love the turbine Thrush and its 150 mph top working speed. In a business where time really does mean money, being able to get the job done quickly and move on to the next farmer’s fields can make a big difference in an ag pilot’s earning potential.

After we’d finished spraying the peanut fields, Terry and I headed about 25 miles south before cutting into the pattern at a private farm strip where we landed and met up with Rick Lott and his 19-year-old son, Shelton. Rick has been an ag pilot for more than 25 years. His father was an ag pilot before him, and as is the case in a line of work that tends to run in the family, Shelton is learning to fly and hopes to be sitting behind the controls of a Thrush agplane himself one day soon.

Rick allowed me to climb aboard his airplane, a nearly new, single-seat Thrush 510P, which he’s flying while he awaits delivery of a 510G on order. What caught my eye was the Ag-Nav differential GPS system in the cockpit of Rick’s airplane. The technology allows an ag pilot to load a map of the field he’s about to spray into the unit’s memory and then follow commands provided by a light bar on the nose that includes left-right indications similar to those of an ILS. The beauty of the system is that it lets the pilot fly a perfect circuit and ensure that every square inch of cropland has been sprayed with no overlap. After the flight, the pilot can eject the data card and give it to the farmer as a record of what was sprayed.

Flying the Thrush
The two-seat version of the 510G is designed primarily for pilot training, although some buyers like having the extra seat so they can bring along a spotter or relief pilot or even extra gear. When flown as a trainer, the instructor sits in the rear seat, where the visibility isn't great and the instrumentation is sparse. On the ground, the view from the back seat is especially poor, owing to the Thrush's tailwheel configuration.

Once Terry landed back at Albany, he asked the tower for permission to taxi to a quiet area of the airport so we could switch seats. To my surprise, the change involved both of us getting out of the airplane and standing on the wing while the engine still ran, the propeller wafting a steady flow of warm jet exhaust over us. I scrambled into the front seat as quickly as I could as Terry gave me a briefing on the controls and instruments.

Once I was settled in, I realized the view from the front seat was much better. If I sat up tall, I could even see some concrete ahead over the nose. For the taxi back to the active runway, Terry had this advice: "Just pretend it's a P-51," he said over the intercom. Actually, with its long, tapered nose and tail-low stance, the airplane was sort of reminiscent of a Mustang. Taxiing and takeoff were similar to that of other tailwheel airplanes I've flown, although none of them had this much power or weighed as much. On the ground, the Thrush's handling reminded me of a Pilatus PC-12 — but one with a tailwheel — maybe not surprising since the 510G's max takeoff weight of 10,500 pounds is nearly identical to that of the Pilatus.

In the air, it was a totally different story. The takeoff run was about what I’d expected, with slight forward pressure required to make the tail come up, followed by slight back pressure to raise the nose and get us climbing at 100 mph. Once we reached 1,000 feet I leveled us off and was surprised to find the airplane seemed to want to keep climbing. Then I looked out each window to the left and right and realized what was going on.

With the nose about where I thought it ought to be to maintain straight-and-level flight, the wings still showed a climb. This was due to the fact that the Thrush in level flight rides slightly tail-high and nose-low. I eased the stick forward to put the wing’s chord line level with the horizon and noted the view out over the nose, which fell away dramatically.

Next, I tried some aggressive turns. That’s when I got my second lesson in flying a Thrush. The airplane has a wide wing, a relatively short fuselage, a big tail and lots of adverse yaw to overcome. It all adds up to an airplane that demands coordinated use of the stick and rudder to keep the ball centered. Let it sling out to one side even a ­little and it will want to travel a lot as the airplane lurches in protest.

After some time at the controls, my touch improved. Performing a series of Dutch rolls gave me a good feel for the Thrush, which is quite responsive and has the maneuverability you’d expect of an airplane designed for aerial application. Next I performed some simulated spray runs at altitude to give me the chance to see if I could come close to matching Terry’s handling over the peanut fields. I decided I’d need a few more hours of practice and instruction — still, of all the flying jobs a pilot might consider, ag spraying would have to rank near the top in terms of fun factor.

That's why I was so surprised to learn that the aerial spraying industry is facing a looming pilot shortage as the current crop of pilots nears retirement. I would have guessed pilots would be lining up to do this sort of work. But as Rick and Terry explained, ag flying tends to run in families, and when an ag pilot's kids don't have the desire to follow in their parent's footsteps, a pilot supply line runs dry.

Returning to Albany to try my hand at landing the Thrush, I found it easy to maintain the 510G’s 90 mph approach speed and ideal glidepath toward the numbers at the power setting Terry suggested. I touched down on the main wheels, slightly tail-low right on the centerline, feeling rather proud that my first landing was a greaser. That’s when I got my third lesson of the day in the Thrush.

During the rollout I never shifted the position of my feet on the ­rudder pedals so that I could press the toe brakes. As the speed slowed and rudder effectiveness lessened, the big taildragger began to wallow on the runway, my feeble corrections with the rudder failing to get the job done. Terry stabbed at the brakes to straighten us out, and I thanked him for the help. It was a lesson I’d need to experience only once.

Thrush is offering the 510G for about the same money as the Pratt-powered 510P. The airplane I flew for this report carried a list price of $869,000 — downright affordable for big farms that think nothing of spending hundreds of thousand of dollars for a new combine. Not surprisingly, many are buying their own airplanes and bringing aerial spraying duties in-house. The trend is helping to fuel demand for airplanes like the turbine Thrush 510G.

For pilots who view the low-and-fast flying of aerial application as a fun challenge, a new career as an ag pilot beckons. After my experience in the 510G in Georgia, I’ll never look at crop-dusters the same way again.

View our Thrush 510G photo gallery.