2 guys missing in Victoria?

[t-bird]

Carb ice is applicable to 912 engines the turbo on the 914 heats up the air before the airbox.The first Mto 3"s had a problem with the fuel pick up in the tanks. The pickup line sucked in air when the gyro pitched up or down that resulted in engine failures. One gyro had 15 litres of fuel left when it flamed out.This problem was corrected in the MTO 3 sport.Quoted from another forum, pilot has an ATPL and is a captain.

FO Gyro wrote:

Had a forced lob yesterday in my MT-03. At the time I had 9 litres of fuel remaining, and at my cruise speed, my cruise fuel flow was 12 litres per hour. This equated to 45 minutes fuel remaining.The problem is the shape of the fuel tank. If one adopts a nose down pitch, the engine can and will become fuel starved as the outlet pipe becomes exposed. After some rough running, and a complete loss of power, I declared a MAYDAY call, and landed in the middle of a rough gravel road, in the middle of a vineyard near Stellenbosch. Fortunately no damage to persons or property. My recommendation is that MT-03 owners should consider 15 litres as unusable for the reasons as mentioned above.

[RickE]

Thanks T-Bird, good to know. As part of my flight plan I always calculate for a 20 litre reserve and put all my fuel through a Mr Funnel. I borrowed some fuel recently and after emptying the drum discovered quite a lot of debris in the bottom of it.......

[Des Garvin]

Hi All, A suggestion to consider as a possible fix for the gyros with the tanks that create fuel starvation in the steep nose down attitude is to have a 5 litre tank that has a pickup hose like a chainsaw where the end is weighted and fallows gravity and the fuel. This would have to be positioned in the line below the main tank so that it is receiving fuel all the time in normal flight conditions. Fuel entry would require to be at the top of the 5 litre tank as well as a air bleed hose back to the top of the main tank. Think that steep nose down operations in a gyro would not be more than a couple of minutes as we do not fly that far above ground level compared to other aircraft. Cheers, Des Garvin

[t-bird]

Per the rotax manual18) CARBURETOR HEAT As with any aircraft engine, carburetor icing can occur in certain conditions. In the case of the 914, operation without an intercooler generally heats the intake air above most icing conditions. When using an intercooler, operators may find that the airbox temperatures are lowered to temperatures where icing is more likely, especially with the heat loss that takes place from the venturi effect of the carbs.

[Waddles]

Gents,My research into the 912s engines fitted to gyros indicates that the anti/de-icing system is aftermarket and not a standard Rotax part number. It uses hot water through a chamber fitted beneath each carby that allegedly heats the butterfly spindle as well as the walls of the carby. One kit offers an optional on/off switch together with a temp gauge for one of the heater chambers.Fixed wings don"t seem to suffer as much as gyros in this regard as the intake air comes from inside a cowling and is heated by the hot engine within the cowl.Another issue that requires understanding is the icing range of temperatures. Carby ice can form when the carby air inlet is between -15* and +15*C. Outside that range, it is unlikely. Note that this is the carby air inlet temp and not ambient temp. The only was to tell this is by fitting a temp probe to the inside of the carby and hook it to a gauge. I believe a kit is available and requires a hole to be drilled into the carby body at an appropriate position for the temp probe.If the carby air inlet temp is below -15*C, ice won"t form BUT the application of carby heat may well bring it up into the icing range. In GA, the general rule without an inlet temp gauge is fully off until the engine coughs, then apply fully and wait for it to clear. Always full heat during descent remembering to turn off during a go-around.Waddles.

[tonydenton]

Note that this is the carby air inlet temp and not ambient temp. waddles, is there a difference if the engine /carbys are not under a cover/ engine cowl.eg. ambient temp.

[birdy]

The 914 is pretty much immune from ice, coz the carbs are fed heated air off the turbo, unless you have a super efficient after cooler.Flown the 914 in many hours of miserable rain of all temps and never once had a cof.

[Brian]

Never got ice in my old pre historic banger in 4000 hours without any heater

[RickE]

From what I have read Birdy is right, rotax advise that if you add an inter cooler to the 914 you increase the chances of carby icing. I"m heading off over the great dividing range next week to Evans head, the more positive information the better.

[tonydenton]

thanks guys , I take that as gospel then. very confusing for me as at the time in the for sale was a similar design. obviously must of been a different set up.

[flyer912]

The 4 banger Rotax is a good donk and I fly my MT with full time water heated carb heat.Baz

[IanM]

Hi all,Over the years I have flown over 400 hours with 912s with the carbie heat installed.

[Waddles]

Gidday Ian and all,I"ve located at least 1 carb air temp kit from Aircraft Spruce. It is relatively inexpensive and should do the job. Here is the link:http://www.aircraftspruce.com/catalo...orairtemp2.php.I note that the caution range on the gauge in this system is +/- 10*, not the +/- 15* I mentioned in my post above.Waddles.

[tonydenton]

thanks waddles, I"m running out of space on my console, but I"m interested.

[Darrell Jones]

Heh Tony, the weather is going to so great, that" you" won"t have time to allow the engine to get cold, you"ll be blasting around the skies.