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Wollongong Ultralight out of fuel?


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You would't just trust the gauges surely. If you don't have a good system you will come unstuck. You can come unstuck with a good system but it's a lot harder, and happens less often, and wouldn't be as embarrassing. This sort of thing seems to be happening more often even though CASA and RAAus have emphasised it lately. Nev

 

 

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You never just trust the gauge on any aeroplane. Doesn't matter what aeroplane it is. Fuel loads have to be backed up by a system of checks, logged fuel burns on/off loads, fuel dips etc. There has to be a back-up. Nev

 

 

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Not sure how many of you actually read the article...

 

What is a "good" system for the jab, especially if more than one person uses the aircraft? When you have a pax it is easy to get near max weight which he would have probably thought he was near as he says the gauge still read a third of a tank when it run out.

 

I try to always put in enough fuel for my flight even though there may be enough going by the gauges already but can't usually do that if I take a pax. The only option the it seems is, don't fly. Rather limits the utility of the aircraft. Which sucks....

 

 

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I read it, local flight. He said he still had 1/3 tank when it started to splutter. If there was 1/3 in there you certainly wouldn't top the tank up and take off without a thorough check of the fuel system, but assuming that was done.

 

This looks like a J170.

 

The J170 has an extremely squat tank, almost impossible for any gauge to read accurately because the fuel is moving around the bottom of the tank.

 

Maybe the rule of thumb should be, never fly without dipping the tank if the gauges show less than half full.

 

Also dip, turn the ac 180 degrees and dip again. The average is what's in the tank.

 

 

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We are talking about 1950's manufacturing standards if we can't get a fuel guage to read empty aren't we? Most car fuel tanks are pretty flat and they seem able to get a pretty accurate reading.

No we're not talking about 1950's manufacturing standards, and these tanks are much flatter than a car tank.

 

 

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And sometimes highlights people who don't want to listen and think things through.

 

The reason the tank is very squat is due to the wing chord, so this is common to most recreational aircraft where wing tanks are fitted.

 

 

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It wouldn't matter how good your fuel gauge is; you are still required to verify fuel quantity by at least two means before flight. The gauge is one ... what about the other ... is dipping fuel tanks a novelty these days, or is it standard practice? It is certainly standard practice in my book.

 

 

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It wouldn't matter how good your fuel gauge is; you are still required to verify fuel quantity by at least two means before flight. The gauge is one ... what about the other ... is dipping fuel tanks a novelty these days, or is it standard practice? It is certainly standard practice in my book.

Some tanks can't be dipped because the internal baffle holes do not line up - can't get to the bottom of the tank. My 2 methods are knowing how much fuel I pour in, and the site gauge of clear plastic pipe on the front of the tanks. Works for me.

It does seem to be a widespread problem in a lot of different aircraft - accuracy of fuel gauges and knowing what's in the tank for sure.

 

Pud

 

 

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.... My 2 methods are knowing how much fuel I pour in, and the site gauge of clear plastic pipe on the front of the tanks. Works for me.

Excellent methods Pud, the site glass or tube properly designed is an excellent visual confirmation and you cannot argue with knowing the number litres going in either.
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To further complicate the wing has dihedral and the fill/dip point is at the high end, the guage obviously at the low end.

 

I dont buy into the weight thing in this case. A J170 is good for 600Kg's and has a useful load, according to J of ~280Kg. The full fuel load is 135L or ~100Kg's so there was 180Kgs for pilot and passenger who was a young female I think I read...... If there wasnt capacity in MTOW for full fuel it should have been damn close.

 

Of course you dont have to be full to fly, but its a fantastic starting point for good fuel management practises.

 

In my 230 I have old style sight glasses I see the fuel sloshing around. I can also see the fuel lines and can see when bubbles of air are in them (assuming I look over each shoulder....I find the rate of looking over my shoulder increases as the fuel drops down the site glass.

 

I also find that if I fly at all with the ball uncentered in the slip guage I can empty one wing tank before the other. The plane by default flys feet off fully balanced at about 105 indicated and at full cruise I have to feed in some rudder to be properly balanced. adjusting the bowden cable end at the rudder can assits with moving the hands off point, but I cant get it to the full 120 indicated. Net result is Im slightly unbalanced at cruise (feet give in before fuel is exhausted) and as such I mentally tend to deduct 30mins of usable time. Of course other J's may well be different. By the way a reduction of 30 minutes still puts me generally outside of bladder range still.....

 

Andy

 

 

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It wouldn't matter how good your fuel gauge is; you are still required to verify fuel quantity by at least two means before flight. The gauge is one ... what about the other ... is dipping fuel tanks a novelty these days, or is it standard practice? It is certainly standard practice in my book.

At my first school (Jabs-and did things very GA-ish) I was told exactly what you are all saying-never trust a gauge and always dip a tank to be sure. Some time later i went to a different airfield (also Jabs) for some unfamiliar territory practise and as I went to unscrew the port wing tank cap, the instructor, looking partly horrified, said "no, what are you doing?"

 

So I'd say there are very widely different practises being taught.

 

 

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I wouldn't call the first school GA-sh Chris, just professional, and I would have given the second one a wide berth after the first visit.

 

We are paying good money, and we don't need to pay it for second rate standards.

 

 

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... So I'd say there are very widely different practices being taught.

As long as two methods of verifying fuel content are used, or one if you can see the fuel lapping at the top of the tank, due diligence has been exercised. If you can't dip J tanks there must be an additional method.
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It's well known to most aviators that good fuel management includes such things as , knowing your aircraft fuel tank/s capacity , establishing fuel already in the tanks , proposed flight time , reserve required , fuel burn at cruise/climb . As has aleady been stated here , the a/c in question , a Jabiru J170 , has long tanks (around 1300mm from memory), around 60mm high due to the low wing profile . Consequently the indication of fuel level in each wing can be significantly affected by the a/c not sitting on level ground . The error can be increased depending on the degree of 'out of level' . To minimise the error and establish the accurate quantity, it is important to ensure the a/c is on level ground ,check both indications and use a dip stick calibrated for that particular a/c . When fuelling en-route I always estimate what the tanks should contain , then dip them before as well as after refuelling. This confirms my fuel burn from time in the air, and the total remaining in the tank from the fuel flow indicator - if installed . As also indicated on this thread , issues such as unbalanced flight can have a significant affect on fuel flow . Like Andy it is not unusual for me to arrive , after a long leg , with one tank completely drained ,which may or may not be indicated in the sight glass . In summary use all resources available to you . As the pilot -in - command , responsibility for the fuel management is yours and yours alone !

 

Bob

 

 

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Most people are used to modern devices working 100%. Look how many idiots drive into the ocean because the GPS tells them too. It certainly looks like the RAA pilot failed to calculate the fuel quantity and the RAA plane failed to highlight the low fuel. Was that due to poor training and maintenance procedures? Either way it reinforces the idea that the RAA is dodgy.Imagine the anguish that passenger when through!

Gidday F.T. Just in case you happen to be serious , here is my response -

 

"Look how many idiots drive into the ocean because the GPS tells them too." - ????

 

"It certainly looks like the RAA pilot failed to calculate the fuel quantity " - Yes even G.A. pilots have been guilty of doing this

 

"...... the RAA plane failed to highlight the low fuel." -the J170 and it's systems have been certified by the aviation authorities. The a/c would have indicated the fuel level in both tanks , the same as a G.A. aircraft , however did the pilot look at both indications , have sufficient knowledge of the systems , and do an independent test ?

 

" Was that due to poor training and maintenance procedures? " - Some training facilities may tend to gloss over these issues , if the guages were indicating properly , then obviously not a maintenance issue either.

 

" Either way it reinforces the idea that the RAA is dodgy " - It does nothing of the sort .

 

Bob

 

 

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my thought is that you should dip the tanks, plus you should know fuel burn and calculate from that how much time you have. Having said that I did once run out of fuel when on a long leg with a head wind I also got an increase from 16 to 22 litres per hour. Cause was a faulty fuel float. On that plane which was a Thruster it is impossible to see the fuel in the pipe when it gets down to about a quarter tank.

 

 

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Hi

 

The Jab tanks are hard to dip because of the wing angle. The J160 I fly here in Deniliquin, I can dip the tanks and it shows maybe a 1/4 inch on each side.

 

Thinking that I need to get fuel I calculate the fuel used after 4 1/2 hours maybe around 70 lts.

 

Go to the bowser and put in 70 + lts but you need to make sure that when the plane was fueled it was fill left, fill right and top up left again to give full fuel.

 

Some of the users here just fill left and then right and do not worry about the left top up again.

 

I have found the guages on Jabs to fairly well indicative of what is left in the tanks but good old hours x lts/hr is the only way to go.

 

A lot of people bag the Jabs because of the way the tanks slope but I have a mate here who has a Piper Saratoga and his tanks are the same and he uses the hours x lt/hr rule as well.

 

Cheers

 

Bruce

 

 

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As a GA pilot and RAA pilot I find that we have to be more than flexible for the situation...

 

For example, as a VFR GA pilot flying an IFR A/C must we then we trust all instruments except fuel gauges?.... "fuel gauges are always wrong" and believe the fuel dip versus burn. "Gauges are only a good indication if you are loosing fuel" I have been told.

 

So we have to be judgemental when picking the instruments we trust when in marginal conditions so it seems... Probably doesn't apply to RAA as we are always VFR..

 

Just don't like the double standard for "trusting the instruments" and "dont trust the instruments" argument.....

 

PS. Which way is up???? LOL

 

 

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