Fuel dip for Jabiru wet wing ?

[Dayble]

Hi all,

 

Anyone made a fuel dip stick for j170/j230 wings ?

 

Was flying a j170 and after a couple of hours, saw the fuel guages showing very low and the EFIS going from 0 to 20 Lt, sometimes just sitting on 0 or 4 for 10 seconds at a time... so we landed.

 

( Thanks Lilydale ! )

 

On the ground, the reading stabilized at 28 lt.

 

I put a stick into each wing and got 1/2 an inch in one and none in the other,

 

( although you could hear it sloshing around )

 

So i put a nother 40 in just to be sure...

 

When i picked up the plane it read 90 lt and that tallied with the paperwork,

 

but who knows ?

 

Unless you put the fuel in yourself, its hard to trust the guages and efis....

 

So maybe i will make a simple stick with markings like used on the Cessna's ?

 

 

[Guest brentc]

Interesting Ian, but no surprises here. We've had similar discussions on here before. One of the biggest problems is the low profile of the tanks. If you dip the tank at say a medium level and the aircraft is not level, then you'll get an erronous reading because the tanks are so long and skinny, thus potentially leading you to an accident inducing condition. Unfortunately the gauge sender position doesn't overcome this problem either.

 

But that being said, 28 litres is not much fuel to have left in those large tanks! Personally if I can and particularly if you're hiring the aircraft it's a good idea if you can afford the weight to start with them full, rather than working from the bottom-up, so to speak.

 

I start with a known confirmed quantity as in visually checking in the tanks or filling a certain quantity myself and calculating what I should have used, in conjunction with the fuel flow meter (or projected fuel flow) and then using the gauges as a backup to try and correlate the two together. Works for me and I'm 'yet' to run out of fuel.

 

If you're worried about the cost of fuel, don't worry, because you still only pay for what you use in the end, unless your syndicate members are stealing from you!

 

 

[blueline]

I have made up a dip stick for my J160 by totally draining the tanks then adding 10 litres at a time, marking dip stick until full.

 

Works very well but as Brentc mentioned the tanks are very flat so is only accurate on level ground - although it is not such a big problem. For example if the aircraft is level with 25L a side, it may show 0 on one side and 50L on the other when on a slope.

 

Because I made the dipstick, and know how it works I can confidently fly with the gauges touching the red. Did not feel comfortable doing this without the dipstick.

 

Does anyone know why Jabiru don't supply one?

 

 

[Dayble]

Hi, and thanks Brent and Blueline - really good comments.

 

I agree, best to have tooooooo much fuel.

 

Thinking ahead to our j230 syndicate A/C ( due Early Dec !!! )

 

we will have some people doing long trips and some doing laps.

 

Prolly not sensible to have the learners doing laps with 120 litres ?

 

Do you know just where the guage sensors are located ?

 

Is there tech data available for that sort of detail ?

 

I have not been able to find it at www.jabiru.net.au

 

At the time, i tried flying very clean and level and also at attitudes to see if i could get an idea of just what was in the tanks, from the movement of the guages,

 

but it is slow to respond...

 

I will still make up a dipstick using a similar procedure to Blueline ( Ta ! )

 

Fuel cost is not a problem. A/C in one nice piece is ! ( and me too !!! )

 

I like the idea of Jabiru supplying or selling one.

 

Like all A/C ( and cars etc ) it is up to the user to do the check

 

on the flat and level...

 

Thanks again,

 

 

[Modest Pilot]

The floats on our J230D's are attached to the wing guages. eg: within 4 inches. But check yours as Jabs are always being upgraded/changed.

 

I don't think you can trust dip sticks much on the J230s. Even 1/2 deg lateral makes a difference and fore and aft level has an effect. Maybe if you carried a laser level it would be O K.

 

 

[Guest Ken deVos]

Just to confuse things, the owner of the J230 I fly at Tyabb has made a dual dip stick to cater for the differences between each wing tank. Sorry, but I cannot quote the exact amount right now, but it is more than you'd think.

 

 

[Dieselten]

I fill tanks to full, then work on 15L/hr (J160C) general average consumption, add up the hours in the Record Of Time In Service, convert to fuel burnt, and deduct amount burned from full amount to get my approximate fuel remaining. When that figure gets below 45L I refuel - all the way to the top, and start again.

 

Tried a dipstick, found it pretty much useless. Tanks too skinny and must be absolutely level to be meaningful. Working on fuel-burn times hours flown is a better indicator IMHO.

 

 

[Guest The Bushman]

Fuel gauges J170

 

A very simple and reliable system of installing a Navman fuel flow system

 

Full tanks add to unit total amount the unit will then count down to empty and on Adding more fuel to the tanks just add the amount to the total remaining in the tanks by the gauge and gives you a accracute fuel burn so any problems can show up before they become a problen and the Type used in Boats have worked fine in both my aircraft the first one for 4 years my Jab at 2800 burnes 15.1 ltres it also includes a low fuel alarm which you can set to any amount.

 

Still used in conjuction with Dip stick and fuel gauges all three items back up each other.

 

:rotary::thumb_up::thumb_up::thumb_up:

 

The Bushman