woodstock
Final Approach
that fuel you dump could be worth a dollar! best to filter it and put it back in.
The new Skyhawks have five sumps per wing, plus three under the engine. I have the POH in the car right now, so can't provide the quote on the volume, but yes, my recollection is at least a cup per sump. Note, though, that the plane comes with a fuel sump cup which holds about 4oz (guestimating). Don't know if they mean one of those cups or an 8 oz cup. Either way, it's a lot of fuel!woodstock said:13 cups? I just get a sampling. and the old plane I fly has 3 sumps.
jkaduk said:Oil is also petroleum based. Would you put gas in your oil?
Greebo said:I hope you do understand that cases like that do not guarantee the same future outcomes.
jkaduk said:Oil is also petroleum based. Would you put gas in your oil?
If the sample is clean and "dry," no problem at all. The problem is when it isn't, and the dump tank provided by the FBO is a long walk down the flight line, or just plain non-existent.jkaduk said:Keep your sample cup clean and if the sample has no water, put it back in the tank. Someone please tell me what's so hard about that and what can go wrong.
jangell said:Including over 40 years worth of crop dusting and airshows. Not one of them sampled fuel. They all said water never would happen...None of them ever busted up an airplane.
Like I said. It was just an interesting example. I never once said to NOT pull fuel samples. Infact I made it very clear that I do. Although I have never found water in any airplane ranging from planes built in the '40s up to year 2000 Skyhawks...Also have never found any in an archerBill Jennings said:Only 2.5 years of flying, but I've pulled water from the Skyhawk 4 times, and once from the Archer. I'll keep pulling samples...
I'd suspect something else. If you are having an issue with water the engine is probably going to cough for a short amount of time or straight up quit. I highly doubt it's going to keep running but just roughly for any amount of time.etsisk said:In my very limited career I've pulled water on more than a few occasions, and (even after sumping) found myself heading back to the airport forthwith with a raggedy engine - suspected of having a water bolus pass through it. No other problems before or since.
AirBaker said:Water in the engine? Try it at home... hook the hose up to your truck's gas tank....
I've seen avgas eat up the ramp, but it's never been around the fuel pump. It's usually been under some aircraft sitting on the ramp dripping fuel. The little samples I take probably evaporate faster than they soak in here, especially on a hot day.
I think this fits under penny-wise pound foolish...
smigaldi said:Mythbuster put all kinds of junk into an engine and had a hard time killing it, but of course they finally did.
BTW I have only pulled water from a tank once. But I'll keep checking. I know one guy whoi had a whole bunch in his tank. One of his engines shut down most likely realted to it, lucky it was just as he landed.
AirBaker said:OWT or actually an issue, either way I'm still sumping it.
Same here and further, I will not ride with anyone who does not sump their fuel. Shows bad decision making skills.AirBaker said:OWT or actually an issue, either way I'm still sumping it.
As I mentioned in an earlier post, the POH for the C172 SkyHawk calls for (and this time I have the reference):SkyHog said:1) Who actually drains up to 12 ounces of avgas? I don't, I have never seen anyone either.
As I further noted, I don't, nor am I aware of anyone who does, do that amount. I do three tubes on every preflight (1 per wing and one on the engine). I just measured, and the standard Sporty's tube holds slightly more than 2 tbsp (30 ml), so I'm doing about 90ml per preflight. That's about 3 oz. Their study estimated 8 oz.CESSNA 172SIM said:Fuel Tank Sump Quick Drain Valves -- DRAIN at least a cupful of fuel (using sampler cup) from each sump location to check for water, sediment, and proper fuel grade before each flight and after each refueling.
I'm sorry, but where does the square footage of the US figure into this? We're really just looking at the ramp and tiedown areas of the airports where the fuel is being dumped, right? Not sure where you got that figure for the square footage of the US, though. Square root is 177,198 ft, or about 35 miles. Please, check my math. If we use an average area of 2000' x 500' for the ramp/preflight area, and posit 10,000 active GA airports (don't we wish), then the square footage is 10,000,000,000, or about a third of your number. This gives us about .0385oz/sq ft.SkyHog said:2) Those 3,007,605 gallons of avgas aren't being dumped on top of each other, but rather, dumped quite far apart, in fact....the square footage of the United States is 31,599,136,800 square feet. So you divide the two and you see that 9.5179973397247990647643260938698e-5 gallons a YEAR is spilled in the same foot (on average). That's pretty good.
SkyHog said:3) The study is flawed from the get go - it neglects the amount of fuel that drains normally from the tanks (and everyone is ignoring that fact too). The reason y'all ignore it is because its a deal breaker. Fuel falls on the ground in a much bigger percentage than you want to admit.
The study acknowledges it in the conclusion.
study said:These figures only represent fuel purposefully sampled, and discarded by pilots performing preflight inspections. It does not include the fuel that drips, or in many cases run out of the fuel tank vent tube when a plane is either over-filled with fuel, or has been topped off in the cool of the evening and then experiences the heat of the following day, thereby expanding the fuel, which then runs out of the fuel tank vent tube. These circumstances amount to a significant quantity of fuel as is attested by the stains on every parking ramp across the country and could add half again the amount of fuel reaching the ground.Let's agree to your assertion that "[f]uel falls on the ground in a much bigger percentage than you want to admit." They admitted 50% additional, so let's double that to 100%. Let's also discount their esimate of the amount drained based on the ratio I found above, 3/8. Yes, I know that this is not fair scientific method. However, once we do that, we see that their numbers come close to showing the true extent of the problem. They overestimated by 33%study said:Additionally, the calculated figure does not include any accidental spills of aviation fuel, nor does it include any jet fuel.
Well, it looks to me as if dumping is half the problem. Not sure how you reached your conclusion.SkyHog said:It sucks, but its the truth. I'm not hurting the environment, the water tables, or the cute little roadrunners that run around my home airport.
According to who? To you? Who believes that his lazyness is, in and of itself, is both G*d-given and, absent laws forcing you to do the right thing - and perhaps in direct opposition to those same laws, sufficient to make it ok to do something that is patently wrong and hurts the rest of us?SkyHog said:It sucks, but its the truth. I'm not hurting the environment, the water tables, or the cute little roadrunners that run around my home airport.
SkyHog said:Good info, with 3 problems:
1) Who actually drains up to 12 ounces of avgas? I don't, I have never seen anyone either.
.
Well, yer likely right about that!SkyHog said:This argument is getting stale (it was last time too), there's no convincing the other side of your intention
gkainz said:Does anyone have information, speculative, factual or even anecdotal, about how long water introduced via fueling might take to be present at the sumps? I'm thinking about the situation where I show up at my trusty rental and it needs fueling before I go. I sump before taking it to the fuel pump, but how long does it take to get a valid sample of the fuel just put into the tanks?