Why you always sump | TheaterFire

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bob152637485@reddit

You bet $5 I won't sip? Deal! (Collects $5 after showing I indeed did not sip).

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have-u-heard@reddit

What do you actually do in this situation? Obviously not fly, but do you just sump until no more water comes out? Or does the whole tank need to be drained?

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Depends on how quickly you get to fuel. If you pull sludge and after a few sample get clean fuel. Rock the wings back and forth and continue your preflight and sump again after some time. If its clean then youre good, also make sure you check the bottom engine sumps as thats the first fuel to end up in your cylinder. Always be extra vigilant after replacing fuel bladders as well as the fuel should lay it all out flat and get rid of any wrinkles thatll trap water and get a good long sump from that too.

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DrRob@reddit

Tell your water supplier it looks like they've got an AvGas contamination problem.

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UntamedRaindeer@reddit

How long was the plane sitting since its last flight? And were the tanks all the way full?

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gimp2x@reddit

I've seen 3x that amount after simply being ramped at lakefront (New Orleans) overnight, the lesson learned for me was, put fuel in the tank, not humid air.....we landed and said we'd get fuel when we departed, we got fuel and then sumped after refueling, I couldn't believe the amount of water that had collected in the tanks

I've also seen similar amounts of water when a fuel cap o-ring failed and let rain water in.....always sump 100LL, always.

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OrangeVapor@reddit

Man, on some planes, I'll regularly sump 3 or 4 bottles full of nothing but water. I usually "clean the plane" with what I sump just to make sure it's actually gas instead instead of water.

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Tyraid@reddit

How long can fuel sit in a tank? Weeks? Months?

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thatonemikeguy@reddit

The fuel is fine for months, but it's the empty space in the tank, that allows moisture in the air to condense in the tank. If you keep your tank filled, less air, less humidity to condense, less water in your fuel.

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Tyraid@reddit

I understand that but at a certain point the fuel breaks down and having it in the tanks is worse than having it out right? I know this could be years but I’m curious.

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gimp2x@reddit

100LL is extremely stable, no issue at all with storage or breaking down

Fun anecdote- jet-a is also, but jet-a with Prist additive will erode a fuel bladder much quicker than without, I really dislike FBOs that premix all their jet-a for this reason

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Mountain-Captain-396@reddit

Mogas "breaks down" (not technically correct but sorta) over time because it contains ethanol which is hygroscopic. Avgas doesn't contain any ethanol or unstable additives, so its shelf life is essentially unlimited.

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Tyraid@reddit

Oh dang that’s cool and good to know

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gimp2x@reddit

Correct! When flying to island or coastal area, fuel when you land to avoid this, but still sump everytime

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TheOriginalJBones@reddit

The most water I’ve ever gotten was from a plane that had sat under a sunshade with nearly empty tanks for a couple days. Dew point can do its thing and make it rain in there.

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DevilishSquirrel@reddit (OP)

Tanks full maybe 3 hours since last flight tops

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Traditional_Half_788@reddit

Was there a damn downpour where you are?

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DevilishSquirrel@reddit (OP)

It rained hard a few days ago but the plane has flown since so idk what happened

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0O00OO0OO0O0O00O0O0O@reddit

Water in the tank you filled from maybe

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1E-12@reddit

Yes more details plz

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redditburner_5000@reddit

Are there people who don't sump?

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Zathral@reddit

I don't.... but that might be because the ones I fly don't have engines

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redditburner_5000@reddit

Those are the best ones.

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Thegerbster2@reddit

Despite it only taking like 30 seconds at most, yes some don't. For most that don't, I imagine it's because for most people you'll never find anything, but in the one case in a thousand that you do, you'll be really glad you checked.

Don't wanna single this guy out because they're unfortunately faaar from the only crash caused by this, but one high profile case was the rebuild rescue guy who crashed in large part to being in a rush and not sumping the tanks.

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chuckop@reddit

It takes more than 30 seconds. On the modern Cessna 172 and 182, there are 5 drain points per wing and 3 under the engine. That’s 13 drain points, and my achy knees have trouble getting under the cowl (I do it, but have learned to bring a kneeling pad with me).

The collected fuel has to be dumped out. I use a GATS jar and pour the right wing and engine drain fuel back into the right wing, and the left drains into the left wing. Climbing up and down on the struts takes time too.

It’s not a lot of time, and it sure is a hassle in any sort of weather, but is not 30 seconds.

Regardless of the amount of time, if you skip it, and the engine sputters on climb out, you’ll wish you had done it.

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yocray@reddit

You guys dump it out?

My school just told us to pour it back in the plane if there's no contamination. I did that when I took my PPL flight test, and the examiner didn't mention anything other than saying it was a lot easier to sump fuel on the older 172s that only had a single drain point.

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theamericaninfrance@reddit

Yeah it sucks, definitely my least favorite part of pre check, especially if it’s windy. Don’t you just love a little spray of LL to the face?

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Thegerbster2@reddit

Ah that's fair, never flown one of those. Surprised there's so many, seems excessive, but I suppose there's more places for water and debris to pool? Or just to decrease chance of missing something?

The planes I fly have 3 (152, 1 per wing plus 1 for gascolator) and 1 (champ, gascolator under single main tank) drain points respectively

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have-u-heard@reddit

Think there were also lawsuits involved with why there are so many

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natbornk@reddit

Older 172’s are like this, one a side and under the nose. Newer ones simply have more “low points” to check.

Contrary to the above, it’s not difficult, nor time consuming. Takes longer to get a weather briefing. It’s part of being a pilot, “do you wanna die or not?”

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falconkirtaran@reddit

The 172 tanks are arranged as several connected tanks in the wing, so there are a larger number of low points to sump.

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Sharp_Experience_104@reddit

Ditto DA40. One per wing plus gascolator.

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320sim@reddit

At my club’s sister school, the FBO went around at the end of the day and topped all 30-40 planes off with Jet A. And while you’d probably notice before you ever took off, you’d cause way more damage by starting the engine if you didn’t sump

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Ok-Selection4206@reddit

A friend of mine ended up getting two new motors on his BE95 after the FBO put Jet A in the tanks after he landed. He found out after he started both motors and taxied for take off the next day.

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GravitationalConstnt@reddit

Wait, don't the different fuel types have unique nozzles to help prevent that?

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320sim@reddit

I wasn’t there so I’m not exactly sure how it happened. It’s suppose it’s possible they filled the truck up with the wrong fuel. Or the line guy was an absolute moron and held the nozzle over the port. There’s ways it can happen

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GravitationalConstnt@reddit

I was thinking that there are morons of all kinds even while I was trying that.

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Thegerbster2@reddit

For sure. That can also be scary with Jet A because if you're not sumping you're probably blowing through your runup as well and it's entirely possible for you to get in the air before it destroys the engine.

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Squawnk@reddit

The instructors at my school tell us not to sump in the winter, but we do it all other times of year

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ym-l@reddit

That sounds sketchy, did they give a reason at all?

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Squawnk@reddit

The reason I was told was concerns over the sump drain getting frozen open and fuel draining out, idk it didn't really make much sense to me so I just sump anyways and haven't had issues

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Thegerbster2@reddit

Yeaaah, no. You certainly can't fly that plane if the sump drain gets stuck open, but that's an issue for the school to deal with. It sounds like they're asking pilots to sacrifice safety so maintenance doesn't have to deal with a potential problem. Sump the fuel every time, no exceptions.

As always the "how would this sound on an NTSB report" test is an important one.

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gimp2x@reddit

Find new school/instructors

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Squawnk@reddit

At this point I'm less than 20 hours from CPL, but I'm definitely going to tell my students to always sump, regardless of the schools policy

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mild-blue-yonder@reddit

Sometimes I fill my plane up, put it in the hangar, and fly the next morning after a thorough post flight. My pre flight on those days doesn’t involve climbing back up on the wing to put sumped fuel back in the tanks.

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Throwawayyacc22@reddit

Judging by the NTSB reports that include “water in fuel” yes, there certainly are.

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mustang__1@reddit

A few years ago getting ready to fly home from I think BDL or BDR or something in CT. It's cold and drizzly (no ice risk but still uncomfortable). Tired after being out all day, etc. Get in the plane and neither of us move for a moment as it slowly dawns on us that neither of us checked the fuel. After confirming that we're both idiots I crawl out and check the tanks. Fucking test tube was half water. I still think it came from the fuel truck since I think we were just out of annual and had fresh gaskets. But yeah... came close to fucking up that night.

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LeatherConsumer@reddit

Definitely

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HailStorm_Zero_Two@reddit

It's legally required here in Australia (prior to 1st flight of the day and after every refuelling) and it blows my mind that it's seemingly optional over there in the states. The amount of things I find in my fuel drains regularly would mean I'll never not do it even if it were optional.

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BrtFrkwr@reddit

Cuz water no burn.

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ribbitcoin@reddit

Gin and whisky

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Reputation_Many@reddit

Reminds me of when a fueler nearly killed me because of water in the fuel. The airplane had arrived the night before with nearly empty tanks and was fueled that night to 1/2 tanks. It was the slow season at a small airport, and no other turbine aircraft had taken fuel there in days. Company policy was to fuel at outstations when possible because it was cheaper, but this time we didn’t have that option.

The next morning before departure, I sumped the tanks and pulled out nearly 10 inches of water using a standard 25-inch Caravan fuel sampler. When I confronted the fueler, he claimed he checked for water three times a day. After I asked him and didn't trust him, I showed it to the airport manager.

The manager pulled the security footage. Turns out, the fueler hadn’t done any water checks on the fuel truck at all for as far back as the footage went. Only the other fuelers had been doing them. He was fired immediately.

There were several guys I worked with there that didn't ever look at the fuel, I am pretty sure that was enough water to starve the engine on takeoff. I always did every time the airplane sat for more than an hour (less than an hour it would be mixed in with the jet fuel most likely from vibrations/movement/etc).

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Future-Project-6074@reddit

Drink it

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CharAznableLoNZ@reddit

I sump every flight and after fueling. Never know if they just pumped a bunch of water into your tanks. I have to walk around anyways, no reason not to.

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Britishse5a@reddit

Drain the water off and put it back in.

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jet-setting@reddit

“Damn, how’d he die again?”

“He wanted to save ten cents of gas. Poor guy.”

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ym-l@reddit

die again?

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jet-setting@reddit

Lol yeah I noticed that after I wrote it.

“Tell me again, how did he die?”

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Throwawayyacc22@reddit

Terrible, terrible idea, worst idea of your life potentially

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firstofmyname02@reddit

Might as well drink the water if you think that's a good idea.

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EmotionalRedux@reddit

I’m going to be honest… I don’t always sump. In fact I almost never sump unless it rained hard or there’s a lot of dew on the wing and it’s the first flight of the day. By my calculation, I’d rather have some small percent chance of dying by water that doesn’t get caught in the runup, rather than dousing myself in lead every time I fly and giving my future kids birth defects

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bandman232@reddit

Probably a stupid question, but do jets have this issue as well? I never hear or larger commercial aircraft having moisture accumulation before.

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OutOfBase@reddit

Most jets have sumps, but we do not sump the tanks. There can be debris that will cause the sump to get stuck open, and then you have a real problem. Sumping fuel is strictly a maintenance function and is not done daily.

That being said, the Jet A fuel handling chain is quite a bit more structured with regular testing at the airlines. Also of note is that jet engines are significantly more tolerant to water than piston engines.

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Ok-Selection4206@reddit

I had a fuel heater servo fail while descending to land at CVG. 767, the motor quit. That will get your attention at 1:30 am.

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Sad-Hovercraft541@reddit

How are you supposed to huff the fumes if you dont sump? 🤔

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sgu222e@reddit

Overall thoughts on the GATS jar?\ Is it worth the investment

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Koffieslikker@reddit

It's nolonger blue here. Little harder to spot

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Mr-Plop@reddit

Those are rookie levels! Try 3 of those per wing.

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ilikewaffles3@reddit

Had the same thing, I was a new student and thought to myself, "isnt 100LL blue?" eventually I got some actual fuel and realized it was all water

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UNDR08@reddit

This gets posted far too regularly.

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gimp2x@reddit

If you ever have doubts as to whether the non blue fluid is water or jet-a (ie, contamination scenario), find a sheet of printer paper and pour the contents out onto it, jet a will stain the paper like a greasy pizza stains cardboard, 100LL and water will not

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KeyOfGSharp@reddit

This is why I lined my fuel tanks with flex seal and also flex sealed the caps. Can't wait for my next flight

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Throwawayyacc22@reddit

I just spray WD-40 in mine, that’s why they call it water displacer

/s

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