How safe is it, really?

"Dan Luke" wrote in message
...

"Happy Dog" wrote:
ALWAYS refuel after every flight, so that we always have full tanks.

I don't know why more pilots don't do this.

I don't know what you are flying, but with the planes I fly, full tanks
aren't an option unless I want to fly alone.

It should be obvious that I wasn't suggesting that anyone overload their
aircraft.

No, but you were wondering why more pilots don't "ALWAYS refuel after
every flight, so that [they] always have full tanks," which is a silly
practice unless one ALWAYS knows the next flight will require full tanks.
At my old club, members were asked NOT to fill the tanks after using the
airplanes, so that the next pilot could add fuel appropriate to his
flight.

To be specific, my concern is that I see many pilots who don't carry more
fuel when they could and within reason. OK?

le moo

"Frank Ch. Eigler" wrote:

Not much, but if it
decides to freeze and get sucked in and collected, could it plug up a
fuel line?

No. Fuel lines have a strainer around them inside the tank. The iceball would
hang on the strainer and would not be big enough to block very much of it.

George Patterson
The desire for safety stands against every great and noble enterprise.

Larry Dighera wrote:

While the amount of water in the fuel system may be small, so is the
diameter of the fuel lines. In the cool environs at altitude, what is
to prevent the water from forming a frozen 'cork' blocking fuel flow?

The fuel strainer inside the tank.

George Patterson
The desire for safety stands against every great and noble enterprise.

Larry Dighera wrote:

While the engine may be able to continue running after ingesting some
water, with an ambient temperature low enough, it wouldn't get fuel if
water in the fuel lines froze. What volume of water is enough to
cause such a frozen plug?

This is just about impossible in the air. Moving water stays liquid at a much
lower temperature than standing water. You are postulating a situation in which
the water in the gas tank is above freezing and the temperature in the fuel
lines is about 0 degrees Fahrenheit. Of course, it's possible for water to get
into the lines on the ground and freeze when the temperature gets below
freezing, but then the aircraft would never start.

George Patterson
The desire for safety stands against every great and noble enterprise.

"Happy Dog" wrote:
To be specific, my concern is that I see many pilots who don't carry
more fuel when they could and within reason. OK?

Now that the goalposts are in a new location, I declare that you have
scored a touchdown.

"G.R. Patterson III" wrote in message
...
This is just about impossible in the air. Moving water stays liquid at a
much
lower temperature than standing water. You are postulating a situation in
which
the water in the gas tank is above freezing and the temperature in the
fuel
lines is about 0 degrees Fahrenheit. Of course, it's possible for water to
get
into the lines on the ground and freeze when the temperature gets below
freezing, but then the aircraft would never start.

Actually, ice in the fuel can freeze in the tanks, forming crystals small
enough to pass into the fuel lines, and then form an aggregate large enough
to restrict (or even block entirely) that fuel line.

An alternative possibility is that the water may freeze in a larger form in
the tank, but not block the fuel intake port from the fuel tank until
something during flight jostles it enough to block the port.

Of course, there is always the standard issue of liquid water in the fuel
tank, possibly shifting and/or coalescing enough during flight to create a
problem just after takeoff or well into the flight.

IMHO, the only real question is how much water you might accumulate due to
condensation. That water in the tanks can cause a problem, whether due to
freezing or otherwise, is simply not a question. It can. As I've said in a
different post, I agree that the chances of condensate accumulating in large
enough quantity to cause a real problem is extremely low. But I don't think
it's reasonable to claim that it could never happen.

Pete

"Dan Luke" wrote in message
...

"Happy Dog" wrote:
To be specific, my concern is that I see many pilots who don't carry more
fuel when they could and within reason. OK?

Now that the goalposts are in a new location, I declare that you have
scored a touchdown.

How so? It's irritating to have comments nitpicked by the dedicatedly
pugnacious. Why didn't anyone go after the original poster and accuse him
of overloading his plane? After all, he said he *always* tops up. That
obvious things have to be made boringly clear is, well, Usenet.

le moo

Peter,

My
understanding is that having the rubber "wetted" by the fuel helps extend
their lifetime.


"Ah, but my fuel bladders will look pristine to the NTSB guys" , said the
pilot as he crashed into the trees at the end of the runway.

--
Thomas Borchert (EDDH)

"Dan Luke" writes:

Remember that in Larry's example the water is distributed among four
tanks. 2mL split four ways ain't enough to worry about.

Perhaps (though others' tanks are much bigger). But as to how such
freezing could happen, consider (not) topping off on such a warm day,
and climbing to 10000 ft for cruise. That temperature drop might be
all you need to freeze out the water. It's not only during winter
that this may be a consideration.

Can someone imagine a scenario where over several heat/cool fill/fly
cycles such ice could accumulate? Perhaps failing to sample the fuel
bowl/drains over several consecutive flights?

If it freezes will it float in avgas or stay on the bottom?

The density of avgas is around 0.7 g/mL, water 1.0 g/mL, ice 0.9 g/mL.
Ice would still drop to the bottom.

- FChE

You are (statistically speaking) more likely to get stuck by lightning,
and win the lottery than get injured in a small plane crash. The only
reason you hear about plane crashes on the news is that they happen so
rarely that each time it is considered newsworthy. Imagine if there
were a front page news report everytime there was an auto crash...

June wrote:
I need some information from people 'in the field'. My husband has
his private license and is just starting to work on his IFR for
recreational flying. He wants to buy into a plane partnership, saying
he will be saving money rather than renting.

We have 2 little girls. I worry for his safety as it seems there is
another small plane crash every other time you turn on the news. I
think he should focus on this hobby when the kids are older, not when
he has such a young family.

Your opinions would be appreciated.