mooniac15u

When I first got my J the fuel caps did not seal properly. If I took off with full fuel the combination of nose-up pitch and low pressure over the wing would cause fuel to come out past the fuel cap. It caused a strong fuel smell in the cabin. I suspect I could smell it in the cabin because the J has a fresh air intake near the tail.

Those are really good questions. Water is an important factor but so is the oxygen in the air. In lab we would remove moisture and oxygen from reaction vessels by replacing it with dry nitrogen. I don't know how practical that would be for an engine and what it would look like when you tried to start it with nitrogen in the cylinders.

In your data it looks like you roughly went from 10 deg C (50 deg F) to 30 deg C (90 deg F) and the RH went from about 50% to 25%. If you look at the graph below you can see 50% RH on the green line which corresponds to about 5g of water per kg of air at 10 deg C. Holding that amount of water constant and moving straight across the graph to 30 deg C you can see that it corresponds to less than 25% RH. Your measurements track pretty closely to the expected change in RH with a constant amount of water. I don't think you are driving any moisture off with your heater.

FWIW, the fuel flow instruments only tell you what is going into the engine, not what is coming out of your tank. I once had a leak at the gascolator that was almost unnoticeable on the ground but apparently was much more significant with fuel flowing. I lost close to ten gallons of fuel during a cross country flight. I was relying too heavily on the fuel flow and not cross checking carefully with my gauges. The engine quit on the ground at my destination. I had plenty of fuel left in my other tank but it was a real eye-opener about relying too much on the fuel flow.

Given a constant amount of moisture in the air, increasing air temperature will decrease the relative humidity because warm air is capable of holding more moisture.

Complaining about the evils of social media on... social media.

The NTSB report says both tanks were empty. Did you know the other one was empty? Did you run it dry per the POH for maximum endurance?

As will mine. I have two batteries and one charges while I use the other.

When Mandatory SBs come up there's usually a chorus of folks pointing out that SBs aren't mandatory for part 91. I'm curious whether this SB is a CYA for Lycoming or if there is evidence that overspeed usually causes actual damage. Do any of the pros on MS have experience with overspeed teardowns? This is a serious question with no intent to be argumentative.

My weedeater has a battery and an electric motor.

Do you have these same concerns when the OAT is 70 degrees? If the engine is held at a relatively constant temperature (including the surrounding air in the engine compartment) how would the outcome be different?

I recently suspended my SiriusXM weather permanently. My homemade Stratux ADS-B receiver provides sufficient weather information for my operations. Canceling SiriusXM was not easy. They don't allow you to cancel online and the phone number they provide on the website is not the number you need to call. In the end I had to talk to 3 different people to cancel my subscription.

I save more than the 1/2 gph x 2000 because I travel more distance in that same time.

Saving 10% on gas in rough numbers is 1 gallon per hour. Assuming 2000 hours TBO and gas at $4 per gallon that works out to $8,000. I can buy new cylinders for that. You've also ignored the prop ECI needed for most M20Cs. If you can get that done for $200 that's another $4,000 spent during an engine lifecycle (assuming 100 hours per year). The bottom line is all planes have maintenance expenses. Some are cheaper in one area and others are cheaper in different areas. Mostly it matters how the plane is operated and where it's stored. There's really no way to directly compare the two. My J has been less expensive to operated on a per year basis than my old D for a similar number and type of flights.

My M20D had bladders and a UL over 1,000 lbs. The weight of the bladders is probably a bigger concern for the mid-body Mooneys.

Once a Mooney has been modified with bladders it is no longer a candidate for the Monroy tank modification. Since the number of Mooneys available to be modified is limited it makes the two products competitors in terms of market share. Someone with a financial stake in Monroy might not be entirely unbiased in recommending against bladders.

It seems to me that bladders and Monroy tanks are competing products...

It seems to me that most folks on MooneySpace don't have a strong opinion either way. There are just a few loud folks who trash on bladders every time it comes up. Most of the loudest have never owned a Mooney with bladders. On the other side I have yet to hear a complaint from someone who has actually owned a Mooney with bladders. I've owned one with and one without. Both are fine. The added weight is not a huge deal and it's nice to have confidence that you won't get leaks. My current Mooney has sealed tanks and that works fine too.

You could say the same thing about an autopilot or any other installed equipment. Each adds weight and each adds value. The amount of value is in the eye of the beholder.

I think you are just evaluating hourly costs which assumes the same number of hours of usage. But hours are not the only way to measure your operating costs. You can also look at what it would cost for each plane to accomplish the same flights in a year. The E should be something like 10% faster and will accomplish those flights in fewer hours. I use my J for roughly the same type and number of flights per year as I used my D but I log fewer hours per year in my J.

I can conceive of a lot of things. I was asking for actual experience. Did you have an internal engine inspection done when you purchased your plane or not? During a normal PPI there shouldn't be much disassembly beyond removing panels. Most owners could reassemble that and fly their plane home. A mechanic on a PPI has no legal basis for grounding an aircraft because they are not doing anything that requires them to sign off. But they could certainly refuse to reassemble the engine and/or sign off on that work as airworthy. People on MS assert a lot of things about what should or should not be done but actual purchases are transactions between humans. Deals break down for much smaller reasons than this. Most sellers I encountered would have passed on the deal and waited for another buyer if I had asked for an engine inspection.

What did you use for installation approval on your aircraft? It would be helpful for others to know what might be needed.

Did you read my original question? How often is a PPI done at the seller's airport by a mechanic known to the seller?

Having it done at home by a trusted mechanic is a completely different scenario. There are absolutely times when inspecting the engine internals is appropriate. Letting a buyer's mechanic pull a cylinder away from home is the setup for an opening post in a MooneySpace nightmare thread.

Isn't the medical implication the real game changer here? It sounds like you might be able to fly a 172 or Cherokee without an FAA medical certificate.