The Mooney has a design problem regarding the sealant on the fuel tanks. If the tanks are not kept constantly full, then the sealant dries out and fuel seeping starts. But to get more than 1.5 full-size people and bags in the airplane, weight and balance demands that the pilot only fill the tanks to the tabs (leaving the tops of the tanks dry.) Fuel to the tabs is essentially never an operational problem because at 9 gph, that's 5.5 hours of fuel (or more conservatively 5 hours at 10 gph.) That's a lot of sitting and in a J-model Money a four-hour range can easily get you to Boston, Orlando/Tampa, or to the Chicago area (unless you're blasting into a serious headwind.)
But because we routinely fuel to the tabs, the sealant dries out and fuel starts to seep on the top of the wing when the tanks are filled past the tabs to the very tops. This creates a mess and might be a concern to a passenger looking out the window who does not realize that an external fuel stain or seep is permitted (in the maintenance manual) and is not unsafe.
But pilots new to the Mooney do not know this fact and have to be continuously educated about fueling procedures. (We had a flight canceled today for this reason.) Re-sealing the tanks generally takes two weeks or more of labor and can cost upwards of $6,000. So to help out, please remember to only have the Mooney tanks filled to the tabs! Thanks.
For general interest, below follows a blurb I put out in 2006. When we were operating three Mooneys for awhile. Everything stays the same !
Fly Smart!
John Hunter
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Mooney Notes
By: John Hunter
August, 2006
I hope that you are enjoying (temporarily) the fact that we have three Mooneys on the line! (Hopefully we'll be back to an affordable two within a month or so.)
I note that some of you have completed your checkouts in 26M. Nice plane, isn't it? This fact compels me to send you a few notes for your consideration which apply to operating our Club Mooneys.
SUNSHIELDS. When putting the sun shields in place please be careful not to crumple or overly bend them. Once weakened, they get soft and they do not stay in position. For the front shields, insert them from the opposite side and then slide them behind the steel bar to the other side. Stuffing them in directly quickly weakens them. (And like any airplane part, they are not cheap!) Slide the right one in first (insert left, slide right) and then the left one last (the one with the strap.) Reverse order when removing. Thanks.
FLAT SPOTS ON TIRES Here we go again! (For the Nth time.). There are brand new tires on both 5FW and on 26M, but in the last two weeks, there have been flat spots applied to a tire on each airplane. I sometimes despair as to what it will take to "get through" to otherwise skilled pilots. Any suggestions?
We've tried all of the harangues we can think of. But we're apparently not reaching everyone. I know that no one does it intentionally, and most everyone that I've actually caught in the act at first denies it, because they can't believe that they are actually doing it. Unawareness and denial are powerful forces in the human brain!
Let it roll, Let it ROLL, Let IT ROLL, LET IT ROLL. When you first think, about braking, DON'T do it! Let it Roll, Let it Roll, then let it roll some more. And when you've slowed to about 40 knots or less, then gingerly, gently, slowly, tentatively, slightly, hardly, lightly, (and perhaps bravely) come up on the brakes. What else can I say?
INTERIOR CARE. Today I found the carpet on the co-pilot's side of 26M shoved forward and bunched up around the rudder pedals. No big deal except that it indicates unawareness (and potentially could cause rudder pedal "stiffness" that might concern the next pilot.
OIL and FUEL. Please note that it has been Club policy for decades to NOT carry oil in the airplane. Oil stains are occasionally the result, and technically, according to the FAA, any item over one pound must be appropriately restrained. Also, in our SOPs we state the Mooneys should be fueled only to the tabs. This is for a reason. Regardless of the fact that tabs in the Mooney conservatively gives you 5 hours of fuel (and a Mooney goes to Tampa or Boston or Toronto in under 4 hours) filling the tanks in a Mooney will generally show stains or even seeps in the top of the wing. (Seeping fuel usually makes passengers nervous, although it is perfectly legal according to the FAA approved maintenance manual.) So please, DON'T fill the tanks in a Mooney!
