New Cessna 150 Owner

You really want to get the prop dynamically balanced on the airplane. It should only be a few hundred bucks, but it will more than likely pay for itself. The more vibration the prop makes, the more you are going to be paying for spinners, engine mounts, exhaust -- not to mention fatigue for you.

There's a guy who's always advertising mobile prop balancing so I'll check him out.
 
I actually like the idea, but it would murder the crank shaft with asymmetrical forces.
Did you actually watch the video? It's not just a broken two blade prop, the short side has a huge weight and the hub is some sort of gimbal. They flew with it and a two bladed prop and although it didn't shake the airplane to pieces and tear the engine off they found the performance disappointing. On paper a single blade prop should be more efficient because it'd be traveling through undisturbed air but I think that assumes the airplane is already traveling fast enough to make that a possibility, this experiment was done with a Cub, an airplane that can barely get out of it's own way on the best day. The big thinkers involved in the Rare Bear had a similar idea about reducing the number of blades from four to three and replacing the existing blades with a design more optimized for the RPM and airspeeds the airplane was running when all of the levers were pushed forward. And it was awesome to witness, that airplane at 500 mph and 4200 hp at 100' off the ground shook not only your insides but also the ground you were standing on. But it also came at a price, these modifications set up unforeseen harmonics, pilots used to talk about being able to hear the airplane coming up to pass them from behind as they were balls out in whatever fighter they were racing, their airplane wasn't the only one getting a bit fatigued by this phenomenon. Had unlimited funds been available the problem could've been managed, but now it's forever retired, not because it was unreliable, inefficient or unsuccessful. It'll never come back because of some very stout legal agreements and a loss of knowledge. Some folks say there's more than one example and I can tell you unequivocally there was only one prop ever built and it'll never fly again.
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Prop overhaul has finally been completed - and only a month after they received it :bang:

Question - does the prop get a new logbook with the overhaul, or is it noted in the old one?
 
@Murdoughnut - I'm N'thing the dynamic prop balance. It's worth it, you'll also learn some cool stuff if the person doing it lets you participate in it.

Having mine done smoothed several harmonics/vibes out in my airplane and made it much more pleasant to fly.
 
Prop overhaul has finally been completed - and only a month after they received it :bang:

Question - does the prop get a new logbook with the overhaul, or is it noted in the old one?

It should have an entry in the existing logbook, including total time since new and history of compliance with ADs and SBs, etc.

Which repair station did the work?
 
It should have an entry in the existing logbook, including total time since new and history of compliance with ADs and SBs, etc.

Which repair station did the work?

H&H props in Burlington, NC did it. I'm assuming they sent a sticker or something with it to throw in the log book.
 
H&H props in Burlington, NC did it. I'm assuming they sent a sticker or something with it to throw in the log book.
Like I said, it depends especially with props. I’ve gotten everything from a sticker in the existing logbook to a new logbook where I had to copy the entry and stick it into the old book. The repair station is required to do an entry for the overhaul but I found that A&Ps generally were lousy about propeller maintenance logs and to get them up to my standards I often had to do some sleuthing and make my best estimates for total time. Especially on the Hartzell props on the Beavers. But my logbooks always kept the FAA happy. Full page size logbooks, with entries printed out on sticker paper. I also had a table at the top where you could type the Hobbs time and it would auto populate TT, TSMOH, and TSHSI as applicable. And of course I updated it at various maintenance events and moved the book the proper binder when props or engines moved around the fleet.
 
H&H props in Burlington, NC did it. I'm assuming they sent a sticker or something with it to throw in the log book.

At the very least you should have a logbook entry IAW 43.9, but the more detailed the better. Such as the shop's work order with measurements before and after the overhaul. My local shop happens to be a certified Hartzell & McCauley service center, their paperwork is very detailed.
 
Oh! The other fun thing on the Beaver props was that they were old enough that the hubs got replaced sometimes, and since the serial number is attached to the hub you would sometimes end up with a “Propeller of Theseus” situation
 
Newly overhauled propeller installed and I took it up this morning for a flight. Seemed to climb much better than before, but I'm not sure if that's because it was about 30 degrees cooler this morning. Still have a few squawks to work out, but at least one problem is behind me.

Question - when I went to record my hobbs times, I noticed that the hobbs never moved during the flight. Fine since I know start and stop times, but that got me wondering ... the plane was sold to me as having just over 8K hours total time. That seems to match what's on the TAC which shows a bit over 8K. Is TAC time typically used as the measure of airframe time? The Ineterwebs seem to tell me both TAC and hobbs.
 
Usually tach time is used for aircraft and Hobbs time is for pilots. This is based on FAR definitions, by the way. However, at the 135 I worked at we used a Hobbs meters driven activated by air pressure to track aircraft time. So there are different ways to do it.
 
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