Is there a problem

[storchy neil]

Fox bat are powered by a rotax motor that have had vapor locks and have had high fuel presure problems

 

To state that fox bat have never had vaporisation or high fuel presure DO you have a new design of motor ?

 

A l 2 LAME refused to sign off on a aircraft that had spidering from the windscreen rivets so what some are saying he was wrong Neil

 

 

[rgmwa]

Fox bat are powered by a rotax motor that have had vapor locks and have had high fuel presure problemsTo state that fox bat have never had vaporisation or high fuel presure DO you have a new design of motor ?

A l 2 LAME refused to sign off on a aircraft that had spidering from the windscreen rivets so what some are saying he was wrong Neil

Neil, sorry but I have no idea what you are talking about. Are you saying that Foxbats don't, but should have fuel return lines. If so, I know of at least one local Foxbat that doesn't and seems to fly fine. On the other hand my RV-12 has a fuel return line, and I'm happy that it does because I think it's a good idea when using Mogas. But what are you trying to say? And what has that got to do with a cracked windscreen. And if an L2 refused to sign off an aircraft that had a cracked windscreen, why would anyone object?

 

rgmwa

 

 

[ozbear]

Hi Neil

 

There is merit for a return system on all rotax powered aircraft especially in high temperature areas using mogas I haven't got the system on my 2015 Foxbat it was a bit of a pain on the earlier foxbats as it transferred fuel from one tank to another in some situations I guess that's why it is no longer used fuel pressure should be governed by the spring in the fuel pump so in situations where it's high it may be a pump problem.

 

 

[storchy neil]

Rgwma to start with a statement that the plane i refered to did not have a vaporisation problem when powered with rotax motors is wrong in my opinion

 

as rotax do have have the requirement for the return line to be directed to the fuel tank NOT ANYWHERE other than the fuel tank this applies to all 912 rotax motors end of story

 

So far no one has shown me or put up in writing that this is wrong legally what I am saying

 

Why has your RV a return line ?

 

Hey I ain't saying the l2 was wrong in what he wanted

 

Yes a new screen was ordered

 

Have old screen any body want to buy it only done a couple hrs gt a couple small cracks 5mm long Neil

 

 

[dan3111]

My two cents worth :).

 

Fuel locks are much like carby icing ,you just need the right condions for it to bite you . If you are a private owner and you just pull your aircraft out and go for a fly and put back in the hanger to next time you might never have a problem . Now if you are a flying school and the plane does a lot of stop starting between lessons the fuel system gets super heated when engine is shut down . So when you start up for the next flight lesson the chance is the fuel boiled on last shot down if a hot day the chance is great . So return line is a must ,I shut my Savannah down one hot day to work under the dash I heard the fuel boil in the lines even with heat wrapping on them . I tend to run the electric fuel pump for a while before the engine is restarted when hot and still leave it on until after take off . I do find this helps in some cases to reduce

 

problems . Now if you are a fox bat owner just because it is 24 certified doesn't make it safe with out a fuel return . Certified is only a plane that has the paper work in order doesn't

 

make it bullet proof . In fact often it works in the reverse as the cost of making mods on certified aircraft is high so manufacture often leaves alone (with problems ) .

 

 

[dan3111]

Now the biggest lesson of all fox bat owners it,s you bum in the seat not the manufacture :) .

 

 

[Geoff13]

Like the Foxbat that had a fuel pump fire in an unfused fuel pump. Still haven't got a response from the manufacturer on that one except that they are no longer fitting fuel pumps.

 

So now no return line and no fuel pump.

 

24 rego does not guarantee safety.

 

 

[storchy neil]

Geoff the explanation I got fox bat are high wing aircraft and don't need a return line as they never will have vapor lock

 

As I personally ask a so call expert why his plane had return return line plumbed into line on up side at the gasculator his reply was "its on there doesn't mater where it goes "

 

Cause if the pump on the motor stuffs up it will flow down to the Carbys

 

The fire from a fuel pump fuel pump that was not fused was in my opinion neglecting bloody basic safety standards

 

How hard would it be to put a tap on a fuel line to stop fuel from cross feeding for crist sake

 

24 rego must be safer ask trek how when these problems are being found on 24 craft Neil

 

 

[ozbear]

Hi Neil

 

A tap would not fix the cross feed its because when the Foxbat is on the left tank the return line dumps fuel into the right tank only .a header tank would be the answer with the return running into it.

 

 

[JimG]

There have been no reported cases of 'vapour lock' in the 1000+ worldwide fleet of Foxbats - except for one aircraft in SE Queensland. ( Silverwing quote from 'Jabiru engine failure, post # 113)

 

Well I wouldn't expect their to be a problem in the UK , it appears the LAA are on to it.

 

http://www.foxbataircraft.com/resources/A22,A22L,A22LS type acceptance.pdf

 

Section 2.6 LAA REQUIRED MODIFICATIONS item 5.

 

cheers

 

Jim G

 

 

[ozbear]

So here's a question is the fuel boiling in the fuel lines or in the carbie bowls or is it on the pickup side of the fuel pump where you would expect due to a lower atmospheric pressure being applied to lift the fuel.

 

 

[storchy neil]

JimG so thank you all others read what foxbat now have made mandatory return line to tank

 

They will not be the only ones to do this every aircraft that is powered by a rotax 912 series motor will get the same directive

 

This to me is in my opinion to late for some as vaporisation and bloody iceing are similar

 

Should you assume that your motor is iceing up you would apply carby heat witch would be counter productive when you have vaporisation

 

With vaporisation you loose power by adding carby heat you loose more power

 

In my opinion this is what has been happening in some aircraft incidents

 

When in my case i had to replace two needle and seats at under 200 hrs this would have been avoided had the l2 lame been more observant and followed the maintainance manual for rotax 912 motors no return line on my aircraft Neil

 

 

[ozbear]

JimG so thank you all others read what foxbat now have made mandatory return line to tankThey will not be the only ones to do this every aircraft that is powered by a rotax 912 series motor will get the same directive

This to me is in my opinion to late for some as vaporisation and bloody iceing are similar

 

Should you assume that your motor is iceing up you would apply carby heat witch would be counter productive when you have vaporisation

 

With vaporisation you loose power by adding carby heat you loose more power

 

In my opinion this is what has been happening in some aircraft incidents

 

When in my case i had to replace two needle and seats at under 200 hrs this would have been avoided had the l2 lame been more observant and followed the maintainance manual for rotax 912 motors no return line on my aircraft Neil

Hi again Neil

I don't think it's a mandatory Aeroprakt modification the way I read it it is a LAA requirement

 

Also the number of foxbats that don't have a fuel return fitted is much lower than 1000 I have only noticed the later A22LS aircraft without them which I think would make the aircraft affected less than 500 correct me if I'm wrong.

 

The added advantage of the return line is it takes pressure off the needle and seat when the engine is stopped helping prevent flooding of the engine from thermal expansion of the fuel in the pressure side of the pump and lines as it heats up from muffler oil tank radiators and engine block which all radiate heat after shutdown.

 

 

[storchy neil]

Yes that directive will in my opinion fix two matters that have been of a bloody concern when I found that it was not on my aircraft over six years ago the so called bloody experts told me that I was wrong

 

First and foremost high fuel presure is eliminated because to match fuel can seize a motor as to little

 

Second with a constant flow of fuel it is not going to vaporise

 

Example is a diesel powered motor should not be shut down when the fuel is very low in the tank

 

Given time were are the experts that tried to shut me up with I was wrong bloody well don't say sorry just go and hide Neil

 

 

[dan3111]

Yes that directive will in my opinion fix two matters that have been of a bloody concern when I found that it was not on my aircraft over six years ago the so called bloody experts told me that I was wrongFirst and foremost high fuel presure is eliminated because to match fuel can seize a motor as to little

Second with a constant flow of fuel it is not going to vaporise

 

Example is a diesel powered motor should not be shut down when the fuel is very low in the tank

 

Given time were are the experts that tried to shut me up with I was wrong bloody well don't say sorry just go and hide Neil

Neil you have missed the hole consept of forums you are meant to hide behind a computer make anything up and shoot from the hip :) then hide before you are found out , someone obvious didn,t explain the rules of the game to you :) .

 

 

[storchy neil]

Oh dan you've noticed

 

:insane:Didn't think you loved me:tongue in cheek:neil

 

 

[ozbear]

Now the biggest lesson of all fox bat owners it,s you bum in the seat not the manufacture :) .

That's the same with all aircraft not just foxbats .

It's the Swiss cheese effect it just takes all the holes to line up .

 

 

[storchy neil]

The whole bloody story ain't getting told

 

When the manufacturer of a motor has installation manual for that motor it has to be followed casa regulation what don't some dxxxheads don't get it about that directive Neil

 

 

[dan3111]

I heard another new fox bat problem a few days ago I thought Savannah were the only ones to have this problem but look out fox bat has it too . Will have to get storchy Neil on to it after he fixes his fuel return .

 

 

[ozbear]

Don't keep us in suspense Dan

 

 

[storchy neil]

now way in hell can I fix the fuel problem when the so called experts cant read installation manuals

 

to be told that return line is mandatory on 912 ROTAX since 2014 how do they explain that rubbish

 

so far I have not been invited to the bloody court house for false and misleading statements made by me about time aint it

 

question ?

 

the last 4 or 5 incidences have the aircraft engine been fitted in accordance with ROTAX installation manual for return line. neil

 

 

[SilverWing]

now way in hell can I fix the fuel problem when the so called experts cant read installation manualsto be told that return line is mandatory on 912 ROTAX since 2014 how do they explain that rubbish

so far I have not been invited to the bloody court house for false and misleading statements made by me about time aint it

 

question ?

 

the last 4 or 5 incidences have the aircraft engine been fitted in accordance with ROTAX installation manual for return line. neil

The first page of the current Rotax 912 series engine installation manual:

 

"This Installation Manual for ROTAX® aircraft engines should only be used as a general guide for the installation of ROTAX® engines into airframes. It does not represent an instruction for the installation of a ROTAX® aircraft engine in a specific type of airframe or airplane. BRP-Powertrain GmbH & Co KG does not assume any warranty or liability in this context.

 

This Installation Manual shall in no event be used without fully complying with the specific instructions and/or requirements of the manufacturer of an airframe or airplane (“Manufacturer”). For verification and/or release of the engine installation, the respective Manufacturer must be contacted. Any modifications or adaptations to the airframe or airplane shall be carried out and/or be verified and released by the Manufacturer only."

 

Rotax write their manuals to cover every possible installation type, not for a specific aircraft. Many GA aircraft (including one of my own) do not have fuel return lines. Aeroprakt aircraft are not dropping out of the sky because there is no fuel return line.

 

 

[storchy neil]

For Christ sake silverwing we had this discussion in your hanger Neil

 

 

[SilverWing]

Like the Foxbat that had a fuel pump fire in an unfused fuel pump. Still haven't got a response from the manufacturer on that one except that they are no longer fitting fuel pumps.So now no return line and no fuel pump.

24 rego does not guarantee safety.

When something potentially life-threatening happens, it's very scary, particularly in an aeroplane. Soon enough, those who experienced the event start looking for causes and those around them understandably want to support them. However, occasionally, comments can get blown into huge issues - sometimes based on a misunderstanding or an unintentional error.

 

First of all, the Foxbat did not have a 'fuel pump fire'. The solid-state Facet fuel pump fitted to the aircraft depends on a good fuel flow through it for cooling - hence the instruction to use the pump only for start up or in the event of a failure in the main pump. At other times, specifically during engine idle, it is possible there is not enough fuel flowing to cool the pump adequately - particularly in engines like the Rotax 912, which have a very low fuel flow at idle. Nevertheless, I understand it was common practice in this aircraft to leave the back-up electrical pump switched on while in the circuit/pattern.

 

Second, the pump was fused and switched - the power to the switch (and thence the pump) clearly came via the blade-fuse box on the lower instrument panel. The pump in the incident aircraft did not experience any kind of electrical failure. It overheated because there wasn't enough fuel cooling it and as a result the heat started to melt and scorch the internal insulation. Perhaps through a misunderstanding, the pump was switched on at the top of a long (low fuel flow) descent or had been left on after starting. Either way the cooling effect of the fuel flow on an engine-idle descent was reduced. Because there was no electrical failure, power continued to the pump, which continued to overheat. The fact that the pump continued to run while overheating caused the operator to think there was no fuse - which in fact there was. In spite of the severe scorching on the pump, there was no fire. The pump cooled and the smoke stopped when the pilot switched the pump off.

 

Third, only three carburettor Rotax engine Aeroprakt aircraft in the world have ever been fitted with electric fuel pumps - all in Australia and all at the absolute insistence of the buyers, with considerable reluctance by the factory. In fact, Aeroprakt, in line with their earlier misgivings, will now only fit electric fuel pumps to fuel-injected Rotax engined aircraft. Of the three carburettor aircraft, the first suffered the fuel pump incident referred to. The second owner has, from the start, observed the 'use only at start up' and has experienced no problems. The third aircraft was optionally fitted at the owners' expense with a non-solid-state Pierburg electric fuel pump configured as for the injection engine, with dual return lines to each tank to alleviate excess fuel pressure, as required by Rotax.

 

I have considerable sympathy with those who experience serious incidents in aircraft. I have experienced some myself. However, the understandable wish to apportion some sort of blame - occasionally revved up by others with their own agendas - should not allow the facts to be ignored.

 

 

[storchy neil]

There for had return line been in accordance with rotax installation manual that would not have happened.

 

Facts are that foxbat did not install return line there for by your own admission you are at fault.

 

Get with it fuel under presure will boil stop making out that it's not happening ROTAX have had the return line to the tank for more years so for you to say it is not required is bulxxxx so sue me if you recond that that you know more than ROTAX.

 

I am talking ROTAX 912 series motors not bloody GA.

 

What size was the fuze ?neil