I've got a new girl now...
... and she's a lot like you... (Honeymoon Suite, 1980s)
From the very first oil change in 55R we've done oil analysis, first through AOA Labs and then through Blackstone Labs, whose reports are more personalized and give opinions on what is happening and why. Beginning last year we noticed aluminum particulates increasing, followed shortly by increasing iron. The oil filter, always cut open and checked at each change, never showed metal. But as the levels reached cautionary ranges we began the move to replacing the engine. We'd been through this before, putting a remanufactured one into "Dimples" in 2007, but what to do this time?
Greg Wright had the answer: A PPONK. Essentially a modified O-470 engine with O-520 cylinders and a few other changes, the PPONK (the developer's last name spelled backwards) develops around 270 horsepower (40 more than the stock O-470), gives longer recommended time between overhauls (2000 hours versus 1500), and has a reputation for smoothness and reliability. The small premium in price for the increased performance was worth it to us, so in early March we dropped 55R off in Greg's capable hands for babysitting till the engine shop, Aero Engines of Winchester, was done with his. A month later, ours went in.
(long pause)
Mid-May came, and the engine appeared ready to go. The timing for pickup was perfect as I was in Maryland visiting Mom and Dad at the same time, so Greg picked me up at Dulles on my arrival in a Sun Country aluminum tube and hauled me to Winchester. The performance was eyewatering - more on that later. But on the second flight the new propeller sprayed red dye all over the windshield, indicating a faulty seal, so we gave the plane back to Tom for keeping while the propeller got reworked.
(short pause)
The end of June found all of us in Maryland for summer vacation. 55R was ready, with a reworked, freshly painted prop hanging on the nose and a new electronic engine analyzer (EI UBG-16 for those of you shopping for one) in the panel to help monitor what I was doing to the engine. Greg, Dad and I flew to Ohio to see Larry Stanford; lunch with Phil Sprang occupied us while Larry, left unfairly at his shop, measured up the panel for new metal, and we beat feet home ahead of an advancing storm. A few days later, the Minnesota Sheltons boarded 55R Airlines for the trip home.
Wow. It's still 55R but she's a new girl now, with a different heart inside the cowl. Some comparisons before and after the PPONK treatment:
Takeoff - shortened by 200-300 feet
Climb - increased by 300 feet per minute
Cruise - increased by 15 knots true airspeed for 2 gallons per hour more
Maximum range - similar, about a 5% decrease
Smoothness - vastly improved
Approach - DIFFERENT. It's easy to get near redline on airspeed, and control forces are higher
A great example of the change was our return flight, 850 nautical miles from Tipton Airport to Anoka with an average 20 knot headwind, very typical of a westbound cruise. With the O-470 our groundspeed of 110 knots would result in a 7:45 flight time; with the PPONK, groundspeeds were in the 125 knot range, shaving almost an hour off (6:48 flight time). We climbed higher more easily, getting out of the summer bumps faster. And the smoothness was noticeable after landing at Anoka, when we all bounced out of the airplane like we had flown from Duluth and not halfway across the country.
Pretty cool.
I'll have more details as I gain experience with the engine. Stay tuned.
From the very first oil change in 55R we've done oil analysis, first through AOA Labs and then through Blackstone Labs, whose reports are more personalized and give opinions on what is happening and why. Beginning last year we noticed aluminum particulates increasing, followed shortly by increasing iron. The oil filter, always cut open and checked at each change, never showed metal. But as the levels reached cautionary ranges we began the move to replacing the engine. We'd been through this before, putting a remanufactured one into "Dimples" in 2007, but what to do this time?
Greg Wright had the answer: A PPONK. Essentially a modified O-470 engine with O-520 cylinders and a few other changes, the PPONK (the developer's last name spelled backwards) develops around 270 horsepower (40 more than the stock O-470), gives longer recommended time between overhauls (2000 hours versus 1500), and has a reputation for smoothness and reliability. The small premium in price for the increased performance was worth it to us, so in early March we dropped 55R off in Greg's capable hands for babysitting till the engine shop, Aero Engines of Winchester, was done with his. A month later, ours went in.
(long pause)
Mid-May came, and the engine appeared ready to go. The timing for pickup was perfect as I was in Maryland visiting Mom and Dad at the same time, so Greg picked me up at Dulles on my arrival in a Sun Country aluminum tube and hauled me to Winchester. The performance was eyewatering - more on that later. But on the second flight the new propeller sprayed red dye all over the windshield, indicating a faulty seal, so we gave the plane back to Tom for keeping while the propeller got reworked.
(short pause)
The end of June found all of us in Maryland for summer vacation. 55R was ready, with a reworked, freshly painted prop hanging on the nose and a new electronic engine analyzer (EI UBG-16 for those of you shopping for one) in the panel to help monitor what I was doing to the engine. Greg, Dad and I flew to Ohio to see Larry Stanford; lunch with Phil Sprang occupied us while Larry, left unfairly at his shop, measured up the panel for new metal, and we beat feet home ahead of an advancing storm. A few days later, the Minnesota Sheltons boarded 55R Airlines for the trip home.
Wow. It's still 55R but she's a new girl now, with a different heart inside the cowl. Some comparisons before and after the PPONK treatment:
Takeoff - shortened by 200-300 feet
Climb - increased by 300 feet per minute
Cruise - increased by 15 knots true airspeed for 2 gallons per hour more
Maximum range - similar, about a 5% decrease
Smoothness - vastly improved
Approach - DIFFERENT. It's easy to get near redline on airspeed, and control forces are higher
A great example of the change was our return flight, 850 nautical miles from Tipton Airport to Anoka with an average 20 knot headwind, very typical of a westbound cruise. With the O-470 our groundspeed of 110 knots would result in a 7:45 flight time; with the PPONK, groundspeeds were in the 125 knot range, shaving almost an hour off (6:48 flight time). We climbed higher more easily, getting out of the summer bumps faster. And the smoothness was noticeable after landing at Anoka, when we all bounced out of the airplane like we had flown from Duluth and not halfway across the country.
Pretty cool.
I'll have more details as I gain experience with the engine. Stay tuned.
posted by The Minnesota Sheltons at 10:53 AM
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