skippydiesel

Follow Up on my SE2 installation; Quick Recap - Fed-up with the SE2 dropping into the footwell at the worst possible moment, I ditched the suction pad, fabricated a dedicated stand/bracket, which sits a bit off centre on my glairshole. This worked very well and had the added bonus of no more "clicks" in my headset. In defiance of uAvionics advice, I connected my SE2, via a quick charge cable, to my Guardian Avionics USB A 2.7 amp charging port. It all seemed to work. It continued to work for weeks like this - don't know how many engine hrs. I must be a geniuses (NOT!) That is until my return trip from Benalla, Vic - No SE2! You guessed it - " it is NOT sufficient to use ANY in aircraft charger as the sole means of charging. To do so will see the batteries deteriorate in 1-2 years to the point where they will need replacing. This is because it is time on charge that is important, as by design the SkyEcho is slow to charge taking 12 hours for a full charge. You don’t fly long enough to charge it and you are using it at the same time, hence it is never fully charged. By all means charge in the aircraft but ensure that at least once a month you put it on a mains 3A 18W charger for at least 12 hours (overnight). " Put the poor thing on charge - took the best part of 36 hrs to get back to full charge. This still leaves problem - How to keep the SE2 charged, when on a multi day flight, without access to the mains? I am staggered that uVionics haven't got a solution for this. I may have to squeeze the rock & spring for a motel room, just to use the mains power to charge the SE2 (expensive solution) My old (15 years?) handheld GPS has both dry cell batteries and connection to 12V cigaret lighter capacity - never a problem. Someone, earlier in this thread, suggested using a battery pack. I actually used my freshly charged one, when overnighting in Benalla. Not for the SE2 but my iPad (flight plan) & phone - just charging these devises took the pack down to 65% - doesn't bode well for charging my SE2. Its been a hard lesson. I hope I have not done too much damage to the batteries - I will now not charge my SE2 in the aircraft. 😈

" Rotax filter is nothing special, but all our US oil filters have a by-pass pressure of 13-15 psi. Rotax used to be 14-16 psi. One psi wasn't a big deal and it isn't even that accurate and that's why you see the psi spread. This allowed too much unfiltered oil to by-pass. Rotax by-pass pressure is now 18-22 psi to stop that. " FYI - This caught my attention (again) Called RYCO - It appears that "most of their oil filters have a 14 psi some up to 29 psi" 😈

I have an AoA through my Dynon Classic - no other stall warning device. Its satisfying to hear it sound, as I flair for landing - tell myself my speed was about right. Have heard it, on rare occasion, in a tight turn, which is good, as it alerts me to keep my speed/power up. The visual display, is way too small and below the glare shield (out of line-of- sight), so its of little use when landing. I guess I could set it to go off at higher speeds but then I may find I am too fast on approach. Many "wax lyrical" about these devises as a landing aid - could be good for STOL, when there is a visual display up on glare shield/HUDS . I wonder if relying on an AoA makes you less able to land without it and possibly airspeed as well ? - something I have had to do on three occasions (tiny little ants in my system).😈

Seems to me that fuel availability would be one of the "limiting" factors ie only go where fuel is available. As with the weather, airfield serviceability - check & check again - who wants to be caught out? I would anticipate this being a VFR only activity, so flexibility on time/duration would be a must. 😈

Some off the cuff thoughts; Seems to me that "joining" could be agreed rendezvouses along the track or a single point. Along the track, may mean that some pilots would have a lonely trip home, from where they leave the group. Single point may be just as bad. Differing economy cruise speeds - could be accommodated by staggered departure times. Keep in radio communication (when/where safe to do so) on 123.45. Regular aircraft condition/location (reference to ground features & any changes to cruising altitude) The point of the exercise would be to end each day at the same landing point. If needs be, help each other out. We would need some sort of emergency plan for illness/injury. 😈

This would be a great challenge for a group of RAA class pilot/aircraft to do (not suggesting that GA pilot/aircarft, of similar performance should not participate). Safety in numbers. Collaborative planning. Possible cost reductions for bulk purchases eg accommodation. All round FUN?? Anyone interested? 😈

I went round Albury - not a huge detour. Benalla is slights SW of Albury, so almost on track after going round Canberra airspace. I don't usually plan to go under controlled airspace, as circumstance may forse me higher than the "step". If I do go under, its a corner, that I can easily go round, if too high. Depends on how big the detour is compared with descending & then climbing again.😈

Well he made a 1Nm call ( on the CTAF), that made no sense (no altitude or intention) and was likly about to pass under me at the time. I made the standard 10nm "Inbound" call with the usual details and intentions. I made an overhead the field call, with descent and X wind join for for runway 18, full stop, details. I heard no other aircraft (on CTAF)within that period . I have an ADSB - OUT and usually a SE2 (short range ADSB IN/OUT). The SE2 was working for the outbound trip but not for the return (investigating). As with all incidents, its an accumulation of errors - ie I may have "seen" him if the SE2 had been working AND he was transmitting an ADSB - OUT signale. 😈

The Oaks- Benalla Outbound -2 hr, 8500 ft 12C. A little cool in the cockpit Return - 2.4 hrs, 7500 ft 5C. Had the forethought to put little chemical heating pads in my boots. Slightly more comfortable than the outbound flight.😈

Just returned from two day jaunt,The Oaks- Benalla (Vic). 2 hrs there/ 2.4 hrs return Stayed overnight in the Gliding Club of Victoria accommodation https://www.glidingclub.org.au/ Basic but clean - friendly staff. On return to The Oaks, had a close encounter with a Diamond DA40 (an incident) - I on X wind for 18 right /full stop at circuit height, hear "The Oaks one Nm south" Looking! Looking! over 36 threshold, suddenly see aircraft banking sharply away below me !!!! I continue on circuit, see a Diamond DA 40 proceeding in a northerly direction - called but no response. I have no idea what the DA 40 pilots intentions were before or after the incident (heard no other calls). Given that I was at circuit height and the DA 40 was below (possibly doing a simulated straight in approach/low pass, which I have seen similar aircraft do quite often) separation was likly +/-500 ft. Thankfully, no blood was spilt ----- this time.😈

I will throw in a suggestion from Rotax Owners Forum; "While I can only speculate as to your low fuel pressure readings, I can perhaps suggest what may be afflicting your fuel flow readings. The EI FT-60 "red cube" fuel flow transducer operates using an optical sensor which senses when the light from an internal LED is interrupted by the rotor passing between the LED and the sensor. Bubbles in the fuel can interrupt (refract) the light from the LED, which the sensor cannot differentiate from interruptions caused by the rotor. Either event will cause the transducer to send a pulse to the EMS. Additionally, because vaporisation (what you've called cavitation) increases the volume of the fuel itself, the rotor would also spin faster for the same mass of fuel passing through. Therefore when fuel vaporisation is present the fuel flow transducer will erroneously present a higher fuel flow measurement to the EMS. This can apply to either or both transducers, but probably not in such a way that the error in one exactly cancels out the error in the other. Turning the boost pump on probably suppresses the formation of vapour in the fuel line, allowing your flow transducer(s) to operate as designed while the boost pump is on. As I touched on above, fuel vaporisation is exactly the same phenomenon as what you referred to as cavitation. From a physics point of view, it doesn't matter whether it is the fluid's temperature rising above its boiling point at a given pressure or if it is the fluid's absolute pressure dropping below its vapour pressure at a given temperature - vapour will form just the same. Excessively low pressure in the fuel line on the suction side of the pump (whether caused by flow restriction/s or a large 'lift' distance) will cause vaporisation just the same as heating the fuel by too much will." 😈

Must have been a UK/Australian pilot, landing against the traffic flow (right instead of left)😈

Thank Thruster, "The instructions re the sensor to keep raw fuel away from it is a concern, is it 100% compatible with ulp? " The problems with the fuel pressure sensor are well documented (check out Rotax Owners Forum). Various "fixes" to pressure reading anomalies have been recommended (all of which I have applied). I have no reason to think that the pressure reading is wrong, more likly effected by bubbles/vapour causing the mechanical pump to loose efficiency/pressure. "When you have the low fuel pressure indication in cruise flight have you tried, without the boost pump, going full throttle.....", No I haven't tried incensing power - will give that a go next opportunity "Perhaps you need a good old mechanical gauge to know what is really happen" Yep! It could only be temporary - no panel real estate left 😈

All true however, if cost a factor in the transponder question - go for an ADSB OUT and an SE2. The ADSB OUT will meet the entry to CTA requirements. SE2 is a low power ADSB in & OUT devise, which will make you conspicuous to aircraft with ADSB IN and/or an SE2, within about 10Nm +. Your EFB (OzRunways or similar) will link to your SE2 and display aircraft with ADSB OUT, SE2 & OzRunways Unfortunatly "legacy" transponders, which are certainly still around in my area, will not display. 😈

For many of us, cost of an ADSB system, is a significant factor, even with the Gov rebate. 😈

Read installation where spell check has delivered insulation

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T510, You seem to be really getting into this little anomaly. "Do you use the boost pump in any other flight modes," Other than what I call high risk situations (TO/Climb/Low level) I do not routinely use the Boost pump (the exception to this rule being low fuel pressure warning)- See my earlier comments "If you don't get the low fuel pressure warning and switch the boost pump on do you still get the reduced indicated fuel flow? " The Boost pump ON, reduction in flow, only happens when flow indication is above that what I would expect in Cruise. High Flow indication is almost the norm ie 17-19L/hr, when I would expect sub 15L/hr. Turn the pump on, more often than not, the flow indication will go to something like what I would expect. "Does the boost pump bypass have a one way valve? " Yes - as stated above. "If it does could this be staying partially open allowing the pump to recirculate fuel?" Interesting thought - please expand. 😈

NOTE: At no time has the engine shown any indication (hesitation) of low/nil fuel supply😈

The wing tank bather, for each tank,is under the op posit outer wing😈

Hi T510, With small aircraft one should always be sceptical about the readings from engine condition related electronic indicators. The fuel pressure indication, pre engine start, run up & TO/Climb are all as I would expect - cant say that it may be "borked" from time to time. I guess I could interrogate/down load the Dynon & see if there is any tendency to bork. As a slight mature person, all this computer stuff is a tad intimidating but will give it go. Its not just pressure anomalies, its also flow. Completely separate & type of sensors so may not be related. 😈

I can't see me developing the complex diagram with all the features you describe (not that good of a draftsman). There is the option to operate from any one of the three tanks (or all three at once) however I use the "header" tank for all operations and the wing tanks to supply the header. While a picture may save many words , I will attempt the words- With the exception engine bay all fuel lines are aluminum. All tanks have their own breather, facing into air flow. A gascolator is located at the bottom of the engine side of the firewall There are three fuel drain valves In line Boost/Auxiliary pump (with a fuel bypass circuit in case of pump failure) used for all higher risk operations - TO/Landing & Low Level Inflight fuel transfer pump A four way wing tank selector valve - Left / Right / Both / Off. This valve is only ever on for fuel transfers The header has an ON /Off valve. On for all flight/engines running operations The system has a fuel return, from the distributor to header tank. This is fitted with a #35 restrictor jet. Fuel return flow was measure (using Boost pump) at 7L/hr The two (30L) wing tanks are located about mid wing The "header (40L) is in fuselage below the glair shield. When full (37 L), this tank may provide some gravity feed Red Cube fuel flow sensors x2 . One located between engine pump & fuel distribution block, the other on the return to tank line. Installed as per instructions however I may change this sometime in the future The pressor sensor is located as high in the engine compartment as possible/above the fuel distribution block to which it is connected via rubber hose (The seal around the sensor, has been intentionally damaged to facilitate ambient pressure entry) Fuel Pressure, Flow, Fuel Remain & Used, are displayed on a Dynon Classic Skyview EMS Fuel Used/Remain indication is acurate to about 1L in 4 hrs Fuel Flow indication only drops below 17L/hr when engine rpm reduced for descent. Calculated (Fuel added) Average fuel flow, for whole of trip, is below 15L/hr (usually 14.25) There is only one "check" valve (other than fuel pumps) which is in the Boost pump bypass circuit The gascolator to engine fuel pump line has been heavenly insulated, to rule out temperature related fuel vaporisation The over engine fuel fines, from pump, through distribution block to carburettors, are all orange fire sleeved, also to mitigate against fuel vaporisation The wing tank fuel selector & Boost pump system/associated plumbing, are in a very"tight package" 😈

Each tank has its own breather, facing into airflow, so should be between ambient and slightly elevated (+) pressure. Correction; My speculation was low pressure (cavitation) in the reticulation system, not in the tanks. For the most part pressures remain stable from Take-Off, through Cruise, to Landing. Not every flight involves a low pressure indication, but it is common. As far as I understand pumps, they all exhibit suction, on the inlet side and pressure, on the delivery side. Rotax 912 use a diaphragm pump. The wing tanks are below the "header". The header may have some "gravity" flow but it would be minimal, primarily when full. Fuel supply is ensured by an engine/mechanical pump. I have yet to determine a consistent "condition" for the low pressure indication. 😈

While I quite enjoy & learn from many of the "thread drifts" that have come to typify this Forum, I am concerned about the tone of some of the respondents and the lack of any relationship to matters aircraft. SO! I thought I might repost this interesting (to me) matter, that is homebuilt aircraft in its origin & intent; "My Sonex/912ULS has an interesting fuel anomaly; To give you some ides where the matter may arise from, I should tell you that my Sonex is fitted with 2 x 30L wing tanks and a 40L in fuselage "header" tank. I call it a "header" because it has no external fuel point, being "fed" from the two wing tanks and the fuel return. I can select from any of the three tanks but prefer to use just the "header" . The plumbing to to achieve, the above, is quite convoluted. I have an electric fuel transfer pump and a "boost" / auxiliary. The latter being used for all higher risk situations i.e take-off/landing, low level operations. For the most part fuel pressure is between 4-5+psi. The anomaly; In Cruise, my Dynon will occasionally (it seems to be quite random) give me a low fuel pressure warning - Pressure may be indicating a low as 1 psi. If I am high, I will just monitor the situaton and pressure will slowly recover, without any intervention on my part. If low, I will turn on my Boost pump for an immediate increase to 5 psi - Turn off the pump, pressure remans between 4-5psi. At no time has the engine ever hesitated. The above is puzzling enough - what could be happening ? BUT There is another weird symptom - When I switch on the Boost pump, in response to low pressure, my fuel flow rate reduces by up to 5L/hr. My Red Cube (x2)/Dynon fuel flow indication has, despite my best efforts to calibrate accurately, never been much good - usually over indicating fuel flow by a significant margin. I think it likly, the indication, with the Boost pump on, is reflective of the actual flow rate in Cruise. The Fuel Used/Remaining is acurate. To rule out engine heat causing fuel vaporisation, I have double insulated the, in cowling, fuel supply to the mechanical pump. The fuel distribution lines from the pump are all coved with orange fire sleeve. My best guess: Due to the convoluted fuel supply system, low pressure is being generated somewhere, causing the fuel to "cavitate". The cavitation encourages bubbles to form. The bubbles effect the fuel pressure sensor - low pressure warning! Why: The above only seem to happen occasionally, I can not explain. Would fuel flow indication, reduce with the Boost pump on? Does my fuel flow, without the Boost pump, indicate high flow? Anyone got any other suggestions?" 😈

An ADSB IN receiver is: Not much good if you don't have the ancillary systems to "see" the transmitting aircraft Overkill, for small recreational air craft , when you can use an SE2, which will display ADSB IN on an iPad (OzRunways) Wont display the older, still legal, transponders (Mode S?) 😈