Query re R44 fuel tanks

[RisePilot]

With the bladder tanks on the R44, full fuel is 46.5 US gallons, (which is technically 47.7gal gals total fuel with 46.5 gals being useable).

My query is if you ran an R44 until either the “low fuel” light came on (3gals remaining) or exhausted the fuel totally and “dipped” the tanks would those measurements show 3 gallons and 0 gallons respectively?

[RisePilot]

To clarify "dipping" is measuring with a calibrated metal stick inserted in main tank (left side) vertically from the filler opening.

[r22butters]

Well my money's on yes

[ianunderdown]

You shouldn't be dipping bladder tanks. You might poke a hole in the bladder.

[octagon]

Wouldn't you expect to see some additional unusable fuel in the tank?

[RisePilot]

The details would inlcude the shape of the bottom of the main tank, location of fuel pickup line and location of the float/measurement device for the fuel gauges.

Also, curious if this is different for tanks that have been retrofitted with bladders as opposed to new production bladder tanks.

[Eric Hunt]

There is also a large variation in results from using a dipstick. Does Robinson make an official one?

 

We made our own, and calibrated it from an empty tank and then added measured amounts and marked the stick as we went. Worked a charm, but operator technique gave differing results by a gallon or two.

[octagon]

http://helicopterforum.verticalreference.com/topic/7512-r22-fuel-stick/

[RisePilot]

Damn, I hope no one in the thread link above is in any way involved in engineering or maintenance.

The problem-solving skills - WTF? rigging tubes, pipettes, wooden dowels with paint or sharpie marker writing on it and the “I’m going to accidentally drop it in the tank”.

How about a simple aluminium (yes spelled/pronounced in proper Queen’s English) bar approximately 5mm thick and 25mm wide with the increments “stamped” into the metal. The top is either shaped into a “T” or “triangle” handle about 8cm wide. You dip it into the tank up to the handle (it can’t fall in, is clean and always measures to the same point).

I don’t know where these come from, but nearly every R44 I’ve flown in Europe has one similar. I’ve never seen the same in the US.

[r22butters]

Damn, I hope no one in the thread link above is in any way involved in engineering or maintenance.

 

The problem-solving skills - WTF? rigging tubes, pipettes, wooden dowels with paint or sharpie marker writing on it and the “I’m going to accidentally drop it in the tank”.

 

How about a simple aluminium (yes spelled/pronounced in proper Queen’s English) bar approximately 5mm thick and 25mm wide with the increments “stamped” into the metal. The top is either shaped into a “T” or “triangle” handle about 8cm wide. You dip it into the tank up to the handle (it can’t fall in, is clean and always measures to the same point).

 

I don’t know where these come from, but nearly every R44 I’ve flown in Europe has one similar. I’ve never seen the same in the US.

 

Allunimum!? (in the brutish Trump's English)

 

We can't afford that! Remember now, we're helicopters pilots, not airline jocks!

[Aluminium Mallard]

Damn, I hope no one in the thread link above is in any way involved in engineering or maintenance.

 

The problem-solving skills - WTF? rigging tubes, pipettes, wooden dowels with paint or sharpie marker writing on it and the “I’m going to accidentally drop it in the tank”.

 

How about a simple aluminium (yes spelled/pronounced in proper Queen’s English) bar approximately 5mm thick and 25mm wide with the increments “stamped” into the metal. The top is either shaped into a “T” or “triangle” handle about 8cm wide. You dip it into the tank up to the handle (it can’t fall in, is clean and always measures to the same point).

 

I don’t know where these come from, but nearly every R44 I’ve flown in Europe has one similar. I’ve never seen the same in the US.

We use wooden downs with the measurements engraved down here... they are specific to the machine. It's often 40 degrees in the shade so the danged avgas tends to evaporate faster than you can read it off one of those fancy alumooooninium ones!

[Eric Hunt]

Ours also was a wooden dowel, with notches carved into it and ink markers for quantity - advantage of a round-ended dowel was that it couldn't damage the tank. And it had a big metal rod through the top, resting on the filler lip, to ensure consistent measurement, and to stop it dropping into the tank. Fitted neatly under the seat.

[iChris]

How about a simple aluminium (yes spelled/pronounced in proper Queen’s English) bar approximately 5mm thick and 25mm wide with the increments “stamped” into the metal. The top is either shaped into a “T” or “triangle” handle about 8cm wide. You dip it into the tank up to the handle (it can’t fall in, is clean and always measures to the same point).

 

I don’t know where these come from, but nearly every R44 I’ve flown in Europe has one similar. I’ve never seen the same in the US.

 

Officially nothing like that for the R44; however, there's a dip stick kit for the R66 that provides a dip stick and holding bracket, $194.00 KI-231 R66 Fuel Dip Stick Installation Kit

 

Enstrom provides a simple wooden dip stick p/n 28-12478-11. Made long enough to keep it from falling into the tank.

'>https://youtu.be/SWjRirVr76s

Edited October 26, 2018 by iChris

[RisePilot]

That Enstrom "stick" could of had the graduation markings more clearly labelled.

 

Also wood stays wet longer, so you now put a fuel coated/smelling stick back into the helicopter. Aluminium dries very quickly before putting it back into the underseat storage area.

[r22butters]

My stick is wood and my underwear asbestos,...bam!

[Eric Hunt]

Wood has the advantage of being softer than anything in the tank that it can come in contact with, so will not cause damage.

 

And Avgas dries very quickly, by the time you read the wet mark on the stick, put the fuel cap back on, and wipe the stick, it will be dry to all intents. Shove it under the seat and it is dry before the machine can crash and start burning.

[iChris]

With the bladder tanks on the R44, full fuel is 46.5 US gallons, (which is technically 47.7gal gals total fuel with 46.5 gals being useable).

My query is if you ran an R44 until either the “low fuel” light came on (3gals remaining) or exhausted the fuel totally and “dipped” the tanks would those measurements show 3 gallons and 0 gallons respectively?

 

The details would inlcude the shape of the bottom of the main tank, location of fuel pickup line and location of the float/measurement device for the fuel gauges.

Also, curious if this is different for tanks that have been retrofitted with bladders as opposed to new production bladder tanks.

 

 

This is what can be determined from the POH and Maintenance Manual, above and beyond that, you’ll need to take your own measurements or call Technical Support 310-539-0508.

 

Bladders capacity: 47.7 total 46.5 usable

Without capacity: 50.1 total 48.9 usable

 

When the gages read E the tanks are empty except for a small quantity of unusable fuel.

 

The low fuel caution light is actuated by a separate electric sender located on the bottom of the main tank at approximately 3 gallons of usable fuel remaining, except for a small quantity of unusable fuel, enough usable for about 10 minutes at cruise.

 

Those details including the shape of the tanks, location of fuel pickup and location of the float/measurement device for the fuel gauges can be found in Chapter 12 of the R44 Maintenance Manual and the bladder fuel tank installation guide, link below.

 

R44 Maintenance Manual

KI-196 R44-series Bladder Fuel Tank Installation Kit Instructions

Edited October 27, 2018 by iChris