Well it bugs me but not enough to fix yet

Timbeck2

Final Approach
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Timbeck2
Anyone got one or more of those things on your airplane? I do. At my last annual I got a heavy right wing fixed by adjusting the rigging cable/s. Since then (last September) I've had a yoke that is turned to the right a tad when I'm flying straight and level. Its like driving a car with the steering wheel turned to the right when you're going straight. I have to be very cognizant when I rotate to keep the yoke turned a bit to the right otherwise I start flying left.

What you got?
 
Anyone got one or more of those things on your airplane? I do. At my last annual I got a heavy right wing fixed by adjusting the rigging cable/s. Since then (last September) I've had a yoke that is turned to the right a tad when I'm flying straight and level. Its like driving a car with the steering wheel turned to the right when you're going straight. I have to be very cognizant when I rotate to keep the yoke turned a bit to the right otherwise I start flying left.

What you got?
Fuel cap was like 15degrees off of parallel to the airflow... but I'm anal and going to town on airplane Mx... so I got it fixed.

Also I don't have an integrated intercom... but that's going to wait until the BIG panel upgrade this winter.
 
My DG has been precessing badly for a long time. It finally died and I’m having it replaced during the annual. Lots of other little stuff.
 
Was it being tightened by the airflow or loosened?
Neither? The airflow is uniform over the cap, so half of the airflow is tightening it and half is loosening it. The center of pressure is in the middle of the cap (which is the center of rotation)... Physics.
 
b8995bb9803f3c4654c04094b500af94.jpg
 
Do you plan on fixing that by getting rid of your vacuum system? My AI works when it wants to and I'm replacing that with a Garmin G5 and seriously thinking about replacing the DG with another G5.
 
I went ahead and did the .3 AMU vacuum pump fix. I really wanted to go dual G5’s but the $5-7k price tag wasn’t in the cards this time around.

Plus, my DG to Stec 30 conversion would cost too much on top of that, and my lazy ass likes the autopilot
 
I've got a few:
1) Fuel sight gauge on wing that is almost impossible to read the cover is so crazed
2) Fuel tank rivet on top of tank that only slightly weeps 100LL
3) Piston engine
 
Neither? The airflow is uniform over the cap, so half of the airflow is tightening it and half is loosening it. The center of pressure is in the middle of the cap (which is the center of rotation)... Physics.
The center of pressure moves with angle of attack and at lower angles of attack is closer to 25% back than mid point.

Things what bug me:
Right fuel tank - needs to be replaced, but it's not leaking at the moment so I still have some time to fabricate the new one (replaced the left this spring - added more capacity in the process).
Heater - ain't none. Got about half the parts fabricated - missing a round tuit.
Strut fairings - need to be bent up and installed. Got the material. Somewhere.
Horizontal stabilizer root faring - one of these days.
 
Any airplane that doesn't have something that isn't perfect is probably either brand new or costs 2x what the fleet average costs to run.

Main thing on the MU-2 right now is that the power levers are split for the same power output at lower altitudes. We could do a billion adjustments to get them perfectly in-line or I could just know that they split in the manner they do and apply power in an appropriate manner so that it's a non-issue. Option 2 is much more practical.
 
The center of pressure moves with angle of attack and at lower angles of attack is closer to 25% back than mid point.

Things what bug me:
Right fuel tank - needs to be replaced, but it's not leaking at the moment so I still have some time to fabricate the new one (replaced the left this spring - added more capacity in the process).
Heater - ain't none. Got about half the parts fabricated - missing a round tuit.
Strut fairings - need to be bent up and installed. Got the material. Somewhere.
Horizontal stabilizer root faring - one of these days.

I've got a round tuit, someplace.
If I find it, I'll mail it to you.
 
The center of pressure moves with angle of attack and at lower angles of attack is closer to 25% back than mid point.

Things what bug me:
Right fuel tank - needs to be replaced, but it's not leaking at the moment so I still have some time to fabricate the new one (replaced the left this spring - added more capacity in the process).
Heater - ain't none. Got about half the parts fabricated - missing a round tuit.
Strut fairings - need to be bent up and installed. Got the material. Somewhere.
Horizontal stabilizer root faring - one of these days.

That reminds me. Cables for both the defrost and the heater don't chooch. I'm waiting for cooler weather to tackle those. In Arizona I've never turned the heat of any kind on in my airplane.
 
Paint. I've been meaning to paint it for 8 years or so. But I'm a pilot and I'm cheap.
 
Fuel gauges conform to FAA regulations, but are otherwise useless
The door gets stuck easily, major pain. I suspect the fix is new seals, but the job is a pain and right now it doesn't leak. I'd like to keep it that way.
That, and it could use some touch up paint here and there. Around the door, wheel wells, that sort of thing.
 
Neither? The airflow is uniform over the cap, so half of the airflow is tightening it and half is loosening it. The center of pressure is in the middle of the cap (which is the center of rotation)... Physics.

I would wager that if you were somehow able to measure the forces on each end of the cap you would not find them to be equal. You're going to have disrupted airflow which is going to cause a pressure differential, which will cause one side to have a higher measured force than the other. Advanced Physics.
 
Fuel cap was like 15degrees off of parallel to the airflow...

Mine has this issue because I replaced old Monarch caps (the ultra cheap ones that are no longer manufactured) with the red Cessna ones. The Monarchs came with their own raised adapter plate and cap assembly. Well the caps wore out and I discovered the Cessna ones fit perfectly onto their adapter panel assembly, but the adapter that the cap screws into isn't clocked correctly so the tabs on the caps are like yours. I thought about removing panel/cap adapter panel assembly, drilling off the 8ish rivets holding them on and re-clocking it and riveting it back together but lost interest in messing with it.
 
I would wager that if you were somehow able to measure the forces on each end of the cap you would not find them to be equal. You're going to have disrupted airflow which is going to cause a pressure differential, which will cause one side to have a higher measured force than the other. Advanced Physics.
Probably. But also none of those forces are going to come close to overcoming the static friction of the gasket, therefore it's negligible. Engineering Physics.
 
We just did the re-rigging as well. The key to getting the yoke right was to zip tie a v-channel to the yokes while adjusting the cable tension and making sure all the cables have the same tension. We also pulled the push rods to the ailerons and one was 1/4 inch longer than the other so that was fixed as well.
 
Mine has this issue because I replaced old Monarch caps (the ultra cheap ones that are no longer manufactured) with the red Cessna ones. The Monarchs came with their own raised adapter plate and cap assembly. Well the caps wore out and I discovered the Cessna ones fit perfectly onto their adapter panel assembly, but the adapter that the cap screws into isn't clocked correctly so the tabs on the caps are like yours. I thought about removing panel/cap adapter panel assembly, drilling off the 8ish rivets holding them on and re-clocking it and riveting it back together but lost interest in messing with it.
My plane has bladders so YMMV. For me it was just unscrewing the outer upper part where the fuel hole ring (yes proper terminology) is fixed to the wing, and rotating it one screw-hole until it was lined up.
 
A right brake that is constantly dragging,have had it checked,to no avail. For a short period it was fine,so every oil change I have them heck the brake
 
My plane has bladders so YMMV. For me it was just unscrewing the outer upper part where the fuel hole ring (yes proper terminology) is fixed to the wing, and rotating it one screw-hole until it was lined up.

Yeah, this is a wet wing and the panels aren't round so I'd have to do a bit more work. I'd rather pick up some salvage panels off ebay and get rid the monarch ones than mess with the ones I have but that falls into this thread again.
 
No because wing center of pressure is looking down the lateral axis of the wing. The center of pressure of the fuel cap is top-down of the wing (fuel cap). A completely different planar view and component of air flow.
I assume we are talking about a cap that looks like this:
06-00985a.jpg

and is not quite lined up with the air flow. In this case, the long tab works like an airflow generating a force to the right or left. Now, at 15 degrees it is probably stalled, but when close to, but not quite, lined up with the airflow it will generate lift to one side or the other and the center of the lift will be somewheres around 25ish percent of the distance from the front which will tend to open or closed depending on which way the tabs are off. Now, the actual magnitude of the force is too small to do anything, but it will be non-zero.
 
I assume we are talking about a cap that looks like this:
06-00985a.jpg

and is not quite lined up with the air flow. In this case, the long tab works like an airflow generating a force to the right or left. Now, at 15 degrees it is probably stalled, but when close to, but not quite, lined up with the airflow it will generate lift to one side or the other and the center of the lift will be somewheres around 25ish percent of the distance from the front which will tend to open or closed depending on which way the tabs are off. Now, the actual magnitude of the force is too small to do anything, but it will be non-zero.

Fair point. I was only thinking of fluid pressure not lift force.
 
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just be happy you’re flying. I think I’m going on 2 months now without a usable plane.
 

In all seriousness we just had our annual and basically took care of all our squawks. That said, there are a few things that still bug me (but aren't really easily fixed). One is sticky landing gear. The struts tend to stick despite the linkages being lubed, nitrogen and oil levels correct, etc. I'm not a fan of the needle gauges for oil temp, fuel pressure, etc. They work fine, but they just seem dinky. I have the toe brakes on the pilot side, which are completely worthless. I'd like to have them removed, but I think it is quite a bit of work. There was a small leak, supposedly our A&P replaced the seals to fix that. Still don't work with a darn. The little machine screw that holds the door catch to the door seal (not sure if I am explaining that well) recently stripped out. Oh...and the small step cracked. This ironically happened during the annual (our A&P is a larger guy...we suspect he actually caused the damage *sigh*)

That's about it.
 
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