In-air oil changes? What?! How did they do it?

kicktireslightfires

kicktireslightfires

Pre-takeoff checklist
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kicktireslightfires
I was reading in the latest issue of Plane & Pilot about the Hacienda, the C172 that back in 1958 flew continuously for 64 days -- over 1,500 hours. OK, the in-air refueling is impressive alone -- they fly low over a long road while a fuel truck hoists a fueling hose up to the wing, the pilot gets out on a ladder and tops up the tanks while remaining airborne -- but how in the world did they effect in-air oil changes every 50 hours? How do you perform an oil change on a running engine to begin with, much less do so while you're in the air?????????????????????? And they didn't just swap the oil, they also changed the oil filter every 50 hours, too! Come to think of it, how did they even keep enough oil onboard for the THIRTY (30) oil changes they needed to perform? Oil weighs 7.6 lbs per gallon, 2 gallons required per oil change = 456 lbs of oil they would have needed to have onboard! WOW
 
I would imagine they plumbed in 2 remote oil filters that could be valved off one at a time while they changed the other one. They also had to have a way to monitor engine oil level during flight. Most likely a sight glass arrangement. The article I read said they pumped fresh oil in to add oil as needed. As far as oil on board, it was passed up on a rope as needed just like everything else they did, food, water, toiletries, clothes, and fuel.
 
They were changing the oil every other day...ugh. I guess they had nothing else better to do.
 
Is that plane still hanging from the ceiling at McCarren? Unbelievable story.
 
I really wonder if oil changes in the usual sense are even needed. Just keep adding fresh oil as the crankcase oil is consumed and sent out the exhaust pipe. IOW a continuous oil change. Should you want a greater rate of "oil change" then simply connect a hose with a valve to the oil drain and open as desired.

My 1964 C-210 with a Continental engine has no oil filter just a screen so unless the screen fills up with debris there is really nothing to do and it has never shown more than a few tiny flecks of carbon at oil changes.
 
Aviation stories like this never cease to amaze me. Thanks for sharing, had never heard/read about this one before.
 
kicktireslightfires said:
I was reading in the latest issue of Plane & Pilot about the Hacienda, the C172 that back in 1958 flew continuously for 64 days -- over 1,500 hours. OK, the in-air refueling is impressive alone -- they fly low over a long road while a fuel truck hoists a fueling hose up to the wing, the pilot gets out on a ladder and tops up the tanks while remaining airborne -- but how in the world did they effect in-air oil changes every 50 hours? How do you perform an oil change on a running engine to begin with, much less do so while you're in the air?????????????????????? And they didn't just swap the oil, they also changed the oil filter every 50 hours, too! Come to think of it, how did they even keep enough oil onboard for the THIRTY (30) oil changes they needed to perform? Oil weighs 7.6 lbs per gallon, 2 gallons required per oil change = 456 lbs of oil they would have needed to have onboard! WOW
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I read that the DC-3 had a way to add oil from inside the plane for those thirsty big radials.
 
L.C. Gray said:
I would imagine they plumbed in 2 remote oil filters that could be valved off one at a time while they changed the other one. They also had to have a way to monitor engine oil level during flight. Most likely a sight glass arrangement. The article I read said they pumped fresh oil in to add oil as needed. As far as oil on board, it was passed up on a rope as needed just like everything else they did, food, water, toiletries, clothes, and fuel.
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Since the latest engines have oil filters one might think that they are essential but really are not. My Conti IO-520a Just has a fine screen which seems to be all that is needed. In fact it isn't even essential since its main purpose is to warn if the engine is generating metal particles. I wonder if this plane had an oil filter.
 
I remember reading about a Ford Tri-motor that I think was out by the Bahamas, or in the Caribbean. They had to shut down one of the motors on one of the sides. Sometime later, the motor on the opposite side developed a low oil level situation. So one of the crew climbs out the strut and drains oil out of the shut down engine, into a leather chart bag. Then they climb back through and to the other strut and engine, and add the oil to the other engine with the low oil level.
 
kicktireslightfires said:
I was reading in the latest issue of Plane & Pilot about the Hacienda, the C172 that back in 1958 flew continuously for 64 days -- over 1,500 hours. OK, the in-air refueling is impressive alone -- they fly low over a long road while a fuel truck hoists a fueling hose up to the wing, the pilot gets out on a ladder and tops up the tanks while remaining airborne -- but how in the world did they effect in-air oil changes every 50 hours? How do you perform an oil change on a running engine to begin with, much less do so while you're in the air?????????????????????? And they didn't just swap the oil, they also changed the oil filter every 50 hours, too! Come to think of it, how did they even keep enough oil onboard for the THIRTY (30) oil changes they needed to perform? Oil weighs 7.6 lbs per gallon, 2 gallons required per oil change = 456 lbs of oil they would have needed to have onboard! WOW
Click to expand...

The refuelling sounds incredible. Even at 50 knots speed, for a 5 minute duration one would need a 5 mile stretch of road. Climbing the ladder, opening the fuel cap etc would take a couple of minutes. They couldn't have had more than 3 or 4 minutes to pump the fuel while maintaining a perfectly parallel flight path over the fuel truck.
 
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