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Posted

Perhaps it is a gravity system. You don't need a giant pressure head. It's a safety risk, and the carb needlseat set up isn't designed for it. It's originally a BMW motorcycle carburettor. 4 feet would be ample. About 1.5 psi at a quick guess. Note any fuel system should be flow checked at installation. Should be near double max anticipated flow rates. I'm not sure of the actual figures, but that's about what I would like to see. Nev

 

 

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Posted
Maybe Neil is meaning .4 barsorry no jimG I mean 6 to 7 bar no point before the 6 or 7 yes you are right in your spiking figures

yes some off you are starting to hear me at 89.4 to 104 .3 psi in the old scale to high for this black duck what is the burst pressure of fuel line where does excess fuel go

 

from what I am hearing Foxbat do not have back up electric pump why ?neil

Unless someone mistakenly installed a high pressure fuel injection pump off a modern vehicle, I call bullsh1t on 6-7 bar. It wouldn't even run it would be so rich, fuel would be pouring out the overflows. 6-7 psi would be believable.

Skilled pilots shouldn't be dying from engine stoppages in any case, a skilled pilot (with no redundant engine)won't fly over something he can't land on or glide clear of. It doesn't matter whether they're flying a two stroke, four stroke, Jab, Rotax or gas turbine.

 

Defence poster in flight line office (B206) "If you fly a single engine aircraft over water for a long enough period of time , sooner or later you WILL get wet"

 

 

  • Agree 3
Posted
Skilled pilots shouldn't be dying from engine stoppages in any case, a skilled pilot (with no redundant engine)won't fly over something he can't land on or glide clear of. It doesn't matter whether they're flying a two stroke, four stroke, Jab, Rotax or gas turbine.

Sound words, but several of the many fatalities we've seen involved just that.

There are airfields operating where the tree growth around two three of four sides of the field is so thick, that ANY low level EFATO is going to be a fatal, other than one you where you have enough runway left to land on.

 

There are quite a lot of cases where the engine stops, the pilot freezes, and a perfectly flyable aircraft stalls or spins into the ground and kills the pilot.

 

Key issues are the quality of the training, the practice level of the pilot, and human factors.

 

 

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Posted

Over time if my recollection serves me well, most of the engine failures were involved with incorrect fuel selection. Landing in trees or factories or houses isn't a thing I would want to contemplate. Golf courses yes. I know of a few of those that went well so perhaps they should be welcomed. Flying single engined pistons out of aerodromes like many are is a bit of a game of Russian roulette. Going back to my first experiences at Newcastle (District Park) and later Rutherford I can't recall many failures at all (if any) The maintenance was of a high order there. Today many "good " engines are good no more. They are older and some of the maintenance is "variable" and they don't get used enough. I won't fly a known "suspect" engine, though some test flights would be marginal or unproven. (that's why they are test flights). If you don't handle a twin properly it will kill you too.. Twice the chance of engine failure. Nev

 

 

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Posted
Sound words, but several of the many fatalities we've seen involved just that.There are airfields operating where the tree growth around two three of four sides of the field is so thick, that ANY low level EFATO is going to be a fatal, other than one you where you have enough runway left to land on.

There are quite a lot of cases where the engine stops, the pilot freezes, and a perfectly flyable aircraft stalls or spins into the ground and kills the pilot.

 

Key issues are the quality of the training, the practice level of the pilot, and human factors.

Agreed, we can learn a lot from human factors, our silly rules only pay lip service. Stalls/spins and LL are all treated like the Wizard of Oz, we are made aware of their existence, but no-one can see the wizard.

 

We know these things can kill us, yet we are prohibited from training (in our aircraft) to build up the necessary skills.

 

 

Posted

Many times the idea of doing unusual attitude recovery has been recommended and most seem to agree with it. If I'd never done it I can't believe I could be considered competent as a pilot. You never know when you will need it. Do it in something like a Decathlon. It shouldn't be the aim of the pilot to make you ill or impress you with his/her pilot skills and it is NOT aerobatics. It includes the concept of energy management which is in the GA training syllabus. The fact OUR planes are not suitable should not preclude you doing it. Nev

 

 

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Posted
Maybe Neil is meaning .4 barsorry no jimG I mean 6 to 7 bar no point before the 6 or 7 yes you are right in your spiking figures

yes some off you are starting to hear me at 89.4 to 104 .3 psi in the old scale to high for this black duck what is the burst pressure of fuel line where does excess fuel go

 

from what I am hearing Foxbat do not have back up electric pump why ?neil

I could've sworn it had a decimal point Neil. I'll try and chase up a link but I know mine (914 with a return line and two electrical pumps as required) runs at 10 psi which from my reading is about maximum aloud which works out to about 0.7 bar (0.689 to be precise!)

Personally I think the return line is important and it does bemuse me that some installations don't use it.

 

 

Posted

This is a link to a simple explanation of the rotax fuel system

 

http://www.experimentalaircraft.info/articles/rotax-fuel-systems.php

 

This is a link to some numbers, please note these are for the 914 and the pressures stated are ABOVE air box pressure NOT overall pressure. Numbers are at the bottom of page 9

 

http://www.rotax-owner.com/pdf/UNDERSTANDING%20THE%20914%20ROTAX.pdf

 

 

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Posted

How about fuel pressure gauges then? How necessary or desirable are they considered to be?

 

 

Posted
How about fuel pressure gauges then? How necessary or desirable are they considered to be?

I'll open myself up here and say I have no idea how necessary they are "legally", BUT I personally think they are just as important (if not more important) as an oil pressure gauge. especially in planes that have switchable tanks after all a plane with no fuel pressure flys just as good as one with no oil pressure.

 

 

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Posted
had a gut full off skilled pilot dyingwho has told you that the builder off your plane does not have to comply with rotax installation manual

re fuel lines or any other item

 

planes that do not have return lines to tank grounded

 

planes that do not have fuel pressure gauge grounded

 

should your plane not comply with the manafactures installation manual grounded

 

no one in Australia has the aurthority to alter rotax installation manual prove me wrong

 

both casa and raaus are negelent in this regard neil

Hi S Neil

 

I agree and have an aviasport fuel pressure guage its great tells me the pressure and that the engine fuel pump is working and I can see when that the electric fuel pump is operating and its pressure; its a great addition to the instruments. Also have the fuel return line with the restrictor back to the right tank IAW Rotax.

 

Cheers

 

Mike

 

 

  • Agree 1
Posted
Hi S NeilI agree and have an aviasport fuel pressure guage its great tells me the pressure and that the engine fuel pump is working and I can see when that the electric fuel pump is operating and its pressure; its a great addition to the instruments. Also have the fuel return line with the restrictor back to the right tank IAW Rotax.

 

Cheers

 

Mike

Whew - you'll be ok then and avoid the wrath of Storchy neil - I'm in trouble though - no fuel pressure gauge ( and I only use my electric fuel pump to prime the carbs) and also no fuel return line. I'm in for a spanking and no mistake!

 

 

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Posted
Whew - you'll be ok then and avoid the wrath of Storchy neil - I'm in trouble though - no fuel pressure gauge ( and I only use my electric fuel pump to prime the carbs) and also no fuel return line. I'm in for a spanking and no mistake!

Hi The fuel pressure guage I find is a good read to allow monitoring what is working. When the engine is running and you switch on the electric fuel pump (eg t/off) you can see the slight increase in pressure. I also fitted the indicator light that lights when the start solenoid circuit is closed (eg it lights during start when the starter is engaged and will stay on when the start solenoid remains closed after finishing the start. It may save a cooked starter and a buggered battery one day. Such happened to an aircraft up this way a month ago.) Such is optional for the 912 wiring; I recommend fitting such.

Best wishes and good flights

 

Mike

 

 

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Posted
Sound words, but several of the many fatalities we've seen involved just that.There are airfields operating where the tree growth around two three of four sides of the field is so thick, that ANY low level EFATO is going to be a fatal, other than one you where you have enough runway left to land on.

There are quite a lot of cases where the engine stops, the pilot freezes, and a perfectly flyable aircraft stalls or spins into the ground and kills the pilot.

 

Key issues are the quality of the training, the practice level of the pilot, and human factors.

I always squeeze the lower cheeks a bit tighter when I fly into or out of CTA around Melbourne. Much of the leg from the Inland Route to south of the Academy for YMMB is all built in now, as is much of the leg between KAO and YMEN.

 

Now I am getting the same reaction when landing at or departing from my home airport of Shepparton to the north...it's all been built in. It's a busy airfield for goodness sake. It has two GA and one RA flying school, and a maintenance hangar; it has a heavy helicopter based here all summer for fire-fighting; the bank plane comes in 5 nights a week; it has an NDB approach (one of the few being retained post ADSB; and I heard the Ambulance Kingair and two HEMS aircraft use it before midnight last night. Greed has replace commonsense in planning decisions.

 

I did much of my early flying in gliders and I always look for the next potential out landing opportunity.

 

Kaz

 

 

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Posted

I agree with Neil, the best engineered engine will still stop with air contamination.

 

Because im rarely above 200', and always lookn outside, iv never been a fan of a gauge for monitering for sumthing as critical as low fuel pressure.

 

Vaporlock starvation is instantainious silence at full throttle, so youd have to be lookn at the gauge to know sumthings amiss.

 

I thought id beet this issue by installing a low pressure warning, thatd get my attention no matter wot i was doing, set to just below WOT pressure. My thinking was, no matter the reason, if the buzzer went off, the fuel in the bowls will give me those precious coupla seconds id need to level and put down.

 

Found out the hard way that, even with the sender unit rigged just before the T to the carbs, and after a mechanical and electric pump, it wont always register a vaporising related pressure drop.

 

Most times it will, but its dependant on the residual temps and the rate of consumption.

 

If consumption is low and the fuel gets hot, and sudden bust of power will demand a big increase in flow.

 

This demand means the pressure in the lines drops fast, the fuel boils under the sudden pressure release, and maintains the pressure, so the buzzer switch didnt trip.

 

Wen ambient temps are above about 43c the buzzer can be annoying, coz its always 'blipping'.

 

But at least i know its workn, and if the blips turn to a howl, get it down, now!

 

 

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Posted

I checked out the roof off the big DFO building at Moorabbin; I'm going in on that for a low level one - big beams a long way apart, so all I have to do is miss a beam and there'll be plenty of spring in the roof.

 

It pays to keep an eye on the golf courses as you come in or out, many aircraft have landed undamaged on the ones around the airport over the years.

 

A young guy in an Arrow had an engine failure west of the Academy and pulled off a landing on Ferntree Gully Road. From memory he went in over the top of traffic stopped at the lights, so he was half way there, but caught one of the hundreds of wires wires on a wing as he let down and that helicoptered him half on the road and half off, and the aircraft caught fire. He managed to get out with his two passengers though. I came past only about half an hour after the event, and although the aircraft was badly burnt, there was surprisingly little damage.

 

Another safety aspect of Melbourne is that in 1971 it adopted a Planning Scheme based on developing radially along corridors where major roads, rail line, power supply and sewerage could be built economically. They planned green belts between these growth corridors, pie slice shaped, which are today's Green Wedge Zones. There are thirteen around Melbourne, and although a lot of illegal building has take place on them there are still many 2 Ha paddocks, and the minimum Lot size from 2003 was set at 40 hectares. There was a fatal RV crash a year or so ago, where the engine failed and the pilot veered for the coast and crashed in a street, bypassing the South East Green Wedge's open paddocks by just a few hundred metres. From the Carrum reporting point you run parallel to a GWZ, from Academy you cross a couple, but have the Dandenong Valley retarding basins. Just takes a couple of hours study and making a mud map and your options really open up again.

 

Drove past Shepparton on the ring road and can't believe how fast it is expanding out past the ring road.

 

Many Planning decisions are about greed, but I've lot count of the number of airfields I've tried to help by advising they get overlays which prevent development, because the people in charge, with no planning experience say something like "They wouldn't listen to us", so no application, therefore no overlay, of "We've got a friend/ex councillor/lawyer helping us thanks" none of which have had any planning experience.

 

 

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Posted

Firstly, I do not believe the '7-bar' or higher pressures for any electrical pump, bar some extremely exotic racing types, or for diesels.

 

However, I am happy to be proven wrong there.

 

HOWEVER: having a fuel pressure gauge is an important diagnostic tool for fuel delivery system check -though you need to have the intelligence to analyse the reporting. Of course, this presumes that you have a properly set-up fuel delivery system, and a properly engineered fuel pressure reporting system.

 

The two key functions of a 'boost pump' are: as a back-up to failure of the mechanical primary pump, AND as a means to overcome vapourisation. For the latter, the boost pump has to be at the LOWEST part of the fuel delivery system. If it is NOT, then your fuel delivery system is deficient.

 

How does this work?

 

BEFORE starting the engine ( and therefore having the mechanical fuel pump active) - you engage the boost pump and see what pressure it delivers to the system. IF that is within limits, then you can 'tick-off' that the boost pump is working.

 

THEN, you start the engine, turn OFF the boost pump, and watch the fuel pressure gauge. If that remains within limits after a short period - (say 30 seconds, as the oil temps come up), you have both the main and boost pumps operating as required, and no apparent fuel vapourisation problems. If there is a significant drop out of fuel pressure limits with just the mechanical pump in operation, EITHER you have: a mechanical fuel pump issue OR vapourisation that has de-primed the mechanical fuel pump..

 

Nobody intelligent takes off if they have to rely on a boost-pump that hasn't been checked for operation for full-fuel delivery to the engine. No matter whether you are out the back of Oodnadatta or somewhere within Turbs's conscienceness.

 

 

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Posted
Premium only FH, i wouldnt put that opal poison in me mower.

Hi Ozbirdy

 

What's the availability of avgas and Premium at places like Warburton, Giles and Carnegie, please? Bulk or drums?

 

Pity they didn't stick with avgas instead of making Opal as a low aromatic replacement for ULP.

 

I'd be really interested in some feedback on Opal in an aero engine, too. I'm terribly unkeen on using it but wondered about a shandy if I became desperate.

 

Many thanks

 

Kaz

 

 

Posted

Firstly let me say that I am aware that Neil is a long time member of this forum and he has a unique style.

 

I am ok with that we all have our own styles and some are easily accepted and others are not.

 

had a gut full off skilled pilot dyingwho has told you that the builder off your plane does not have to comply with rotax installation manual

re fuel lines or any other item

 

planes that do not have return lines to tank grounded

 

planes that do not have fuel pressure gauge grounded

 

should your plane not comply with the manafactures installation manual grounded

 

no one in Australia has the aurthority to alter rotax installation manual prove me wrong

 

both casa and raaus are negelent in this regard neil

In the above OP of this thread Neil stated that "planes that do not have fuel pressure gauge grounded" as per the Rotax installation manual.

 

When I queried that fact ( I didn't say it was wrong, just asked for clarification) I was quite rudely and bluntly put in my place and told as you can see below to get new glasses.

 

Neil to his credit did give me his reference, which by the way has now been replaced with a later version, helps to read the latest one Neil even though I can't see any glaring differences in this section.

 

get new glassesrotax 912 1997 manual installation of rotax 912 power plant return line to right hand tank

BRP rotax 912 2012 installation manual for rotax 912 B R P power plant return line to tank with a none return valve

 

page number 1 to 10 item number 73-00-00

 

there has never been an ad to change this neil

So above I was told to get new glasses and it was inferred, and in a later post stated that I had obviously not read the manual. (That is tantamount to calling me a liar).

 

Well Neil if you call me a liar then I am coming head hunting.

 

I then quoted Neils reference and highlighted where the manual states what is required and a fuel pressure gauge is not required as per the Rotax installation manual.

 

I thought at that point Neil may apologise for calling me a liar and correct his error. But no such luck.

 

He just swung the discussion to why there should be one. Now I do not know enough about it to know if we should or should not have one suffice to say that of the 15 or so planes that I have flown I am not aware of any of them having one fitted. Most of those aircraft are LSA's so you couldn't fit one if you wanted unless the manufacturer approved it.

 

He then quoted several pressure requirements that need to be met to have safe flight. After noticing the glaring error in Neils figures I said nothing, however JimG offered Neil an out and suggested that maybe he had left out a decimal point and even explained why. Well below was Neils response obviously he hadn't made an error in his opinion.

 

Maybe Neil is meaning .4 barsorry no jimG I mean 6 to 7 bar no point before the 6 or 7 yes you are right in your spiking figures

yes some off you are starting to hear me at 89.4 to 104 .3 psi in the old scale to high for this black duck what is the burst pressure of fuel line where does excess fuel go

 

from what I am hearing Foxbat do not have back up electric pump why ?neil

Well Neil I would be more than happy to lend you a pair of my glasses or you could duck down the chemists and purchase a pair for around $10.00

 

If you care to refer to your own reference,

 

"BRP rotax 912 2012 installation manual for rotax 912 B R P power plant return line to tank with a none return valve

 

page number 1 to 10 item number 73-00-00"

 

The stated fuel pressures

 

Max 0.4 bar (5.8psi) or 0.5bar (7.26psi from pump serial 11.0036)

 

Min 0.15 bar (2.2psi)

 

As has been said Neil has a unique style, and he has a special interest in this area. I respect those two facts.

 

However just because your style is loud and/or abusive, it does not make you more correct nor does that alone make your statements correct.

 

Nor does being a member for a long time or being a friend of the site owner make your arguments any more valid.

 

I was not offended by you telling me to get new glasses as that is your style and I recognise that fact and accept it.

 

I was however offended by being called a liar and have waited for almost 48 hour to allow you the opportunity to retract your comments or apologise. You have done neither.

 

As a result I have felt it necessary to call you on your errors and suggest that you read the same reference that you accused me of not reading.

 

I spent 7 months of my life fitting a Rotax 912ULS in accordance with the Installation Manual to the best of my abilities.

 

To be told my aircraft should be grounded because someone has an axe to grind and interprets the Manual differently to me and all the reference people that I spoke to quite simply pisses me off.

 

I am aware forums are just that and the written word can be misconstrued. I am also sure that Neil and I given a face to face meeting would get on fine and would probably after a simple discussion come to an agreement on this issue. But this is a forum and as such irrespective of your style you should try and write to the audience available.

 

Sorry if I have come across as a bit harsh Neil but get your facts right and be Man enough to "Fess Up" when you stuff it up.

 

 

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Posted
Firstly let me say that I am aware that Neil is a long time member of this forum and he has a unique style.I am ok with that we all have our own styles and some are easily accepted and others are not.

In the above OP of this thread Neil stated that "planes that do not have fuel pressure gauge grounded" as per the Rotax installation manual.

 

When I queried that fact ( I didn't say it was wrong, just asked for clarification) I was quite rudely and bluntly put in my place and told as you can see below to get new glasses.

 

Neil to his credit did give me his reference, which by the way has now been replaced with a later version, helps to read the latest one Neil even though I can't see any glaring differences in this section.

 

So above I was told to get new glasses and it was inferred, and in a later post stated that I had obviously not read the manual. (That is tantamount to calling me a liar).

 

Well Neil if you call me a liar then I am coming head hunting.

 

I then quoted Neils reference and highlighted where the manual states what is required and a fuel pressure gauge is not required as per the Rotax installation manual.

 

I thought at that point Neil may apologise for calling me a liar and correct his error. But no such luck.

 

He just swung the discussion to why there should be one. Now I do not know enough about it to know if we should or should not have one suffice to say that of the 15 or so planes that I have flown I am not aware of any of them having one fitted. Most of those aircraft are LSA's so you couldn't fit one if you wanted unless the manufacturer approved it.

 

He then quoted several pressure requirements that need to be met to have safe flight. After noticing the glaring error in Neils figures I said nothing, however JimG offered Neil an out and suggested that maybe he had left out a decimal point and even explained why. Well below was Neils response obviously he hadn't made an error in his opinion.

 

Well Neil I would be more than happy to lend you a pair of my glasses or you could duck down the chemists and purchase a pair for around $10.00

 

If you care to refer to your own reference,

 

"BRP rotax 912 2012 installation manual for rotax 912 B R P power plant return line to tank with a none return valve

 

page number 1 to 10 item number 73-00-00"

 

The stated fuel pressures

 

Max 0.4 bar (5.8psi) or 0.5bar (7.26psi from pump serial 11.0036)

 

Min 0.15 bar (2.2psi)

 

As has been said Neil has a unique style, and he has a special interest in this area. I respect those two facts.

 

However just because your style is loud and/or abusive, it does not make you more correct nor does that alone make your statements correct.

 

Nor does being a member for a long time or being a friend of the site owner make your arguments any more valid.

 

I was not offended by you telling me to get new glasses as that is your style and I recognise that fact and accept it.

 

I was however offended by being called a liar and have waited for almost 48 hour to allow you the opportunity to retract your comments or apologise. You have done neither.

 

As a result I have felt it necessary to call you on your errors and suggest that you read the same reference that you accused me of not reading.

 

I spent 7 months of my life fitting a Rotax 912ULS in accordance with the Installation Manual to the best of my abilities.

 

To be told my aircraft should be grounded because someone has an axe to grind and interprets the Manual differently to me and all the reference people that I spoke to quite simply pisses me off.

 

I am aware forums are just that and the written word can be misconstrued. I am also sure that Neil and I given a face to face meeting would get on fine and would probably after a simple discussion come to an agreement on this issue. But this is a forum and as such irrespective of your style you should try and write to the audience available.

 

Sorry if I have come across as a bit harsh Neil but get your facts right and be Man enough to "Fess Up" when you stuff it up.

Agree...

You have my support there Geoff..

 

 

  • Agree 1
Posted
from what I am hearing Foxbat do not have back up electric pump why ?neil

Maybe you should ask Foxbat that question, I have and I know the answer. In fact I was part of the reason that they stopped fitting them.

 

 

  • Like 2
Posted
Maybe Neil is meaning .4 barsorry no jimG I mean 6 to 7 bar no point before the 6 or 7 yes you are right in your spiking figures

yes some off you are starting to hear me at 89.4 to 104 .3 psi in the old scale to high for this black duck what is the burst pressure of fuel line where does excess fuel go

 

from what I am hearing Foxbat do not have back up electric pump why ?neil

The Aivasport fuel pressure gauge for the 912 engines read in whole numbers X 0.1 ; 4 is 0.4 bar.

 

98990181_aviafuelpressureguage.gif.938eb7264062ea5fc5bde48c5aeaac4e.gif

 

 

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Posted
The Aivasport fuel pressure gauge for the 912 engines read in whole numbers X 0.1 ; 4 is 0.4 bar.[ATTACH=full]41583[/ATTACH]

That agrees with the installation manual.

 

 

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