Airfields with Mogas

[BirdDog]

On local then cross country...

At the moment, I fill up the airplane I train in at Cowra from the 98 bowser (in Cowra) into Jerrys and cart them to the airport, and fuel 'my plane', I do the alcohol test on new fuel, and and dump the bottom of the jerry cans .

 

Now, if I am planning a cross country, seems I need to either

 

a) go avgas : dump the MOGAS out of the system and go to AVGAS for the trip.

b) stay mogas : have a sufficient endurance to en route via MOGAS availability either at the airport, or get into local town with a couple of 20 litre jerrys or transport bladders. Or carry extra inboard

 

is this the general method ?

 

Why are you dumping anything??

 

If I need to fill up on AVGAS, just fill up!

[RFguy]

While the mfrs say it is not recommended , I am yet to see any definitive evidence knowledge based reasons why NOT to mix. Just got to be aware and cogniscent of all the potential MOGAS pitfalls. (IE volatiles evaporation, ethanol, water, vapourlock etc) As usual . I was reading about people using 25% AVGAS, 75% MOGAS no issues, for a bit of lead for the top end of the engine, for engines that needed it.

[onetrack]

The oil companies/refiners are your best guide to fuel use. Avgas and Mogas keep their fuelling abilities satisfactorily, if stored in air-tight containers - for months.

However, if there is any ability for air to enter the fuel container, there is an ability for the volatile components of the fuel to escape - thus lowering startability and fuel performance.

 

This means that vented fuel tanks will gradually lose a certain percentage of the volatile ingredients over a period of weeks.

This is the reason road vehicles have sealed fuel systems, because the volume of volatile compounds being released from fuel tanks vented to the atmosphere were seen to be becoming a major pollution problem. This automotive fuel system design change happened in the early 1970's.

 

Mixing Avgas and Mogas is quite acceptable, provided that you understand the octane rating is lowered, and the volatile aromatic compounds in Mogas lead to a lower vapour pressure than Avgas.

Avgas is paraffin based, with the more stable paraffinic compounds offering a higher vapour pressure than the volatile compounds in Mogas, which is refined from aromatic hydrocarbons.

Additionally, Avgas contains Tetra Ethyl Lead, which protects the valve seats in engines without valve seat inserts. Most engines of recent manufacture have hardened seats, it's the older engines that can be affected by the lack of TEL.

[Kenlsa]

RF. The reason not to continually run with a mixed brew is that the factory will "certify" their engines to performance standards on ONE type of fuel, neat. Then they may do it for another. For example Jab have approved Avgas OR Mogas, ( no ethanol tho) but not continually mixed.

They will not do it as they have zero control over the respective properties. Imagine running an engine test with 10%, 20%, 30% etc mix of car/plane fuels, then getting down to 1% increments after that. The cost would be mind blowing.

The factory allows you to transition mix the fuel from one to another when converting.

Ken

[RFguy]

understood

[Old Koreelah]

NFW ! I am not having switches and contacts with electrical currents going click near gasoline. You gotta be kidding ?!!!! ?????. (maybe near kerosene but not gas)

(I have a background in intrinsically safe environments- I have an aversion to explosive environments and electricity)

Another source of sparks: I’ve been advised that in certain conditions static electricity can be created by fuel pouring into the funnel. I have a plastic shroud around mine to encase the fuel vapor and, hopefully, keep its concentration too high for ignition.

[RFguy]

you want to careful, especially wearing acrylics etc, that you dont draw a spark touching something around a filler on the skin of the aircraft etc. Also, the aircraft is insulated from the ground, in the wind, it would be possible, to build up some charge sitting around minding its own business. make contact with the aircraft first away from vapours I'd suggest.

I wear 100% cottons when I fly. cotton socks, cotton /leather shoes , jeans, cotton jacket etc. seems to be few problems.

We don't hear of too many aircraft filling accidents though.

[Downunder]

There is a filter in most petroleum bowsers, so if the hose and Jerry's are clean., should be OK. ... There would be the potential for the fueling nozzle at the bowser to get dirty, so that needs some attention. Lots of dirt and crap accumulates around the filling cap of my vehicle. Still, I'd like ahand pump and filter and hose. I can reach up to the filling caps on the high wing brumby.

https://www.recreationalflying.com/threads/tell-us-about-your-last-flight.21911/page-84

Post #1667....

[onetrack]

Synthetic clothing is the greatest static-producer you can get, Watch these people set their cars alight by jumping in and out of the seat whilst refuelling (videos follow on).

 

[walrus]

You should have an earthing clip on your hose and an earthing point next to the fuel cap. The hose should be fuel hose which is conducting, not plastic. Mr. Funnel makes a conductive plastic funnel. A purpose made electric fuel pump (eg Holley) SHOULD be intrinsically safe.

 

Most dangerous time is a still, cold winter morning. We blew the back wall out of a service station once. The tank vent was just above the roofline. The space in the double brick wall filled with fumes. The owner went to make a coffee for the tanker driver. The wall disappeared when he switched on the electric jug!

[skippydiesel]

You can utilise an electric automotive fuel pump, but the connections you install are the critical area. A properly-designed petrol pump is totally flameproof. Arcing at connection points is a real threat.

No "consumer level" electric pump is designed for pumping petrol, they all specify "diesel only".

The danger is in the fumes, not the liquid. Remember, petrol fumes in confined spaces have substantial explosive power - and even in unconfined spaces, they will start a fire from many metres away.

After you've watched a 200 litre drum, containing nothing but petrol vapour, travel 300M after it's been ignited (purposely, for demonstration purposes), you gain a whole new level of respect for the power in petrol fumes.

 

Sorry - Not true! I use a Holly type "vain" positive displacement petrol transfer pump - have had no problems over the last 5 years or so. You will find this discussion/photos etc elsewhere on this Forum

[skippydiesel]

Hi One track .yes all correct ! you wont find me using an electric pump with wires dangling out of it near gasoline, unless the cable is double sheathed in stainless braid, the connection double strain relieved and fuel proof flex plastic over-molded into a pump with a failsafe internal barrier between the motor and the liquid housing. I agree there are safe pumps, but the hand pump us OK for me only 60-150 litres... . I'm not pumping 500 litres in. The certified intrinsically safe explosive atmosphere gasoline pumps with all their suitable wiring and connections all foolproof is not cheap. Call me risk averse, but fueling an aircraft with gasoline is a hazardous activity IMO, and hence I will do it in a suitable risk mitigated manner.

 

I bow to your academic knowledge - however with care & attention to detail ( remote switch, sealed pump, static line and well vented area) the risk is negligible. See my comment above.

[jackc]

Sorry - Not true! I use a Holly type "vain" positive displacement petrol transfer pump - have had no problems over the last 5 years or so. You will find this discussion/photos etc elsewhere on this Forum

 

Turtlepac use a Holley pump for fuel transfer from their bladders.

 

 

[onetrack]

Skippy, you may have been using a Holley vane-type fuel delivery pump successfully for 5 years - but all I'm saying is, that your connections to the Holley pump are not explosion-proof, not certified for pumping petrol, don't meet any Australian Standard for petrol-pumping equipment - and you may find yourself in trouble if you start a fire, and damage results. Your insurance may not cover you.

 

IMO, the simplest and most foolproof method of fuel transfer involves a little air pressure. You only need 2-3psi to transfer fuel, and all fuel containers will handle considerably more pressure than that figure.

 

https://www.aircraftspruce.com/catalog/pspages/goatthroat.php

[RFguy]

I'm a big fan of air driven pumps. but I mainly see then on irrigation- pumping water up from a river. the 1/4" air line runs down the middle of the poly pipe to the pump . sounds like a frog croaking.

 

great link onetrack

Glen.

[onetrack]

The site below is a helicopter website, but it's a pretty useful page to keep potential refuelling problems uppermost in your mind.

 

Note that the story of the helicopter pilot getting burnt by a fuel explosion says, "as the alligator clips came off the battery terminals, they touched, and caused electrical arcing".

 

The alligator clips did not even have to touch anything, as soon a connector carrying power is (accidentally) disconnected, you have an arc.

 

I have a friend who was burnt badly simply by opening the flip top of a steel jerrycan, whilst securing it between his legs.

 

The jerrycan had been warmed by the sun, and the petrol expansion made the higher level of petrol in the can gush out, over his legs and feet.

 

There was a campfire burning some 8 to 10 metres away, the fumes drifted straight to the fire and ignited, and the flames travelled back to the jerrycan, and set him alight within a few seconds.

 

http://brumbyhelicopters.com.au/refuelinginfield.htm

Edited September 17, 2020 by onetrack

[skippydiesel]

Skippy, you may have been using a Holley vane-type fuel delivery pump successfully for 5 years - but all I'm saying is, that your connections to the Holley pump are not explosion-proof, not certified for pumping petrol, don't meet any Australian Standard for petrol-pumping equipment - and you may find yourself in trouble if you start a fire, and damage results. Your insurance may not cover you.

 

IMO, the simplest and most foolproof method of fuel transfer involves a little air pressure. You only need 2-3psi to transfer fuel, and all fuel containers will handle considerably more pressure than that figure.

 

https://www.aircraftspruce.com/catalog/pspages/goatthroat.php

 

No offence taken - all advice welcome-

 

I have gone to considerable trouble to spark "arrest" my system - all electrical joints are double shrink taped.

 

My switch is similarly "coated" and on the end of a long lead.

 

My power supply is via long lead and Anderson plug in cockpit - connection is made befor opening tank, fuel can and only disconnected after all closed.

 

I have a earth connection to ground and the engine - aircraft is compost, as is tank, so no ground there.

 

I only fuel up with hanger doors open, keep fill spout down in funnel (low Oxygen) and suction spear almost fills the neck of fuel can.

 

This fuel transfers system is fully portable and goes away with me on long trips, for decanting 20 L fuel bladders.

 

Yes there is still a risk but then leaving the ground is a risk, as is driving, riding horses,, alcoholic beverages and smoking substances, etc etc

 

Its all about management & acceptable levels - life is risky and I wouldn't want it any other way

[Roscoe]

Hmm... I would not mind seeing the data on this. Yes, fuel changes over time, but 2 weeks. No. After about 5 weeks or so it has a little bit of a change that only make your engine run rich - not what I would call damaging!!

 

Given that I run 95RON as prescribed by Rotax, I am not concerned.

 

https://www.bp.com/content/dam/bp/country-sites/en_au/australia/home/products-services/fuels/opal-factsheet-storagehandling.pdf

And if you stick to the Manufacturers recommendation, that is good enough for me!

Jabiru recommend Avgas and have published very comprehensive reasons as to why.

So its Avgas for me in the Jab.

[RFguy]

actually they say MOGAS is fine, if you take care. they caution about ethanol.

 

https://jabiru.net.au/wp-content/uploads/2018/05/JSL007-7_Fuel_Guidance.pdf

[Roscoe]

And if you stick to the Manufacturers recommendation, that is good enough for me!

Jabiru recommend Avgas and have published very comprehensive reasons as to why.

So its Avgas for me in the Jab.

Just to clarify, Jab also say MOGAS acceptable but recommend AVGAS in preference due to perceived quality control issues in mogas

[RFguy]

yeah, its about controlling the MOGAS variables. which isn't too hard. I was talking to a guy in the NT, he runs MOGAS when available, and when en route where MOGAS can be got, but keeps drums of AVGAS on his property due to the relaxed storage requirements in his case.

[skippydiesel]

No offence taken - all advice welcome-

 

I have gone to considerable trouble to spark "arrest" my system - all electrical joints are double shrink taped.

 

............................................................................................................................................................................................

 

Yes there is still a risk but then leaving the ground is a risk, as is driving, riding horses,, alcoholic beverages and smoking substances, etc etc

 

Its all about management & acceptable levels - life is risky and I wouldn't want it any other way

 

I knew I had missed something:

 

My quest to find a less physical way of fuelling my aircraft.

 

In my mind, I have not aged but the mirror and my inability to hold 20 L of fuel at chest hight for more than a few minutes, tell a different story.

 

You talk of "risk" - well what risks are involved with a less than youthful old git trying to put fuel into his aircraft using a 20 L drum held at chest hight?

 

I can tell you.

 

Its all good as I hoist the 20 L up -Ssloooowly tip the opening/nozzle toward the funnel. Splosh splosh, gurgle gurgle... DAMN! I am starting to shake. SH........T its splashing over the side of the funnel. Every expletive I know - I have a fuel drenched leg - it stings it stinks and I dont have a thought about fire. Put the damn drum down -, take a brake, try again.

 

There is a better way and it may have risks but probably less than having carcinogenic hydrocarbons repeatedly splashed on large areas of aged skin, never mind the discomfort of the the smell or the stinging .

[Kenlsa]

My SP has a fuzz refuel point. I have had 2 spine ops any I find it very convenient to just lift the Jerry to waist height. No need to take any steps as well.

Ken

[JG3]

Synthetic clothing is the greatest static-producer you can get, Watch these people set their cars alight by jumping in and out of the seat whilst refuelling (videos follow on).

 

 

She was very cool the way she handled that flareup.