Franky

Thanks KR I am leaning toward getting it repaired also. I am not sure with the HDX whether I like the engine bottom band or not. I have defined a bottom band and a 50% engine screen and may elect to use the 50% page and have no bottom band. I will try both when I get into the air Franky

Hi All I have a 2015 10inch Dynon Skyview Touch screen that recently started exhibiting the “rainbow of death” with a convoluted and slow boot times. This is a known problem with Skyview and requires the unit to be returned to Dynon for repair at a fixed cost of $650US plus shipping one way. The unit is then re-warranted for 1 year. I took the opportunity to upgrade to an HDX, so my dilemma with the old screen is whether I get it repaired and then sell it. I am unsure of the demand for such a screen in Oz, although I notice in USA there is a demand for backup and 2nd screens. Any comments? Franky

No brainer! Just do it Wired into your headset gives you early stall warning by ever increasing frequency of beeps as the stall approaches. Also displays a graphic on screen showing how close to stall you are. Wiring in audio to your headset you also get any system warnings annunciated into your headset enhancing your instrument scanning Franky

Why not follow the manufacturer’s recommendations?

Alternatively, put the “red cube” on one carby only and multiply calibration pulses/litre by 2. Have used this on a 912ULS with return line for over 5 years. Typically have less than 1 litre error per 300 litres of flying Every 500 litres or so drain remaining fuel and check/reset fuel qty. Franky

Another technique is to put the fuel flow transducer in line with one carby only and assume that the other carby uses the same amount of fuel, ie balanced. This means you multiply the fuel flow calibration by 2. This works surprisingly well. I check the calibration every 500 liters or so and the error is less than 0.5%

Hi Murray Increasing the voltage on the Ducati regulator used on the 912 ULS is achieved by inserting the appropriate forward biased diode in series with the “C” terminal and the battery positive. The regulator senses the battery voltage via the “C” terminal and when it gets to its preset level it will begin to turn the regulator off so that the float voltage is kept constant. By inserting a diode, the voltage at which the regulator begins to turn off is increased by the forward drop of the diode. The actual diode and type of diode to use is determined by the increase in voltage required. Diodes forward voltage drop at low currents can vary from 0.3 to 0.8 volts approximately. Schottky diodes provide lower forward voltage drops than silicon diodes. In my case I used a schottky rectifier diode MBR1100 from my local Jaycar, which has a forward voltage drop of 0.4volts at 20ma. This raised my voltage from 13.8 to 14.2 volts. Before you choose a diode, accurately measure the cutoff voltage of the regulator by allowing the battery to fully charge with minimum other loads, measure the battery voltage preferably at the battery terminals then calculate how much you want to increase the voltage by. Then you can look at the specs of common rectifier diodes (schottky and silicon) looking for a forward voltage at low current that is closest to what you require. The diodes are cheap - you might get a few different ones to try. Ideally the diode is mounted in a position with the least temperature variation, although a variation of 75deg C will only change the voltage by about 100mv. In addition the temperature coefficient is negative which is desirable anyway. Take care that the connections on the “c” line thru the diode to the battery positive sense point are secure, as an open circuit will cause the regulator voltage to rise uncontrollably. Hope this helps Franky

It is great tool to add to your situational awareness tools, along with eyeballs and radio. In the past 18months I have had a dozen or so occurrences where without adsb in I was completely unaware of nearby and potentially conflicting traffic, especially on designated vfr routes. Even when I knew exactly where to look on occasion I have not sighted the aircraft. It is amazing how many aircraft do not fly at hemispherical levels or on the wrong side or an air route. Also very useful when around airports with commercial traffic which almost always have adsb out. I wouldn’t fly without it; just take care of its limitations and use it as a supplement. Franky

I would be interested to know if ozrunways takes into account adsb altitude referenced to 1013mb. If so, it would need to know the local qnh, where would this come from? Avplan can look up the nearest airport with a qnh and display that ( not used to adjust target altitude) Needs internet access though - not always available. Franky

Hi Be aware of how you interpret traffic on EFBs. I use a flightbox adsb receiver with avplan. Great for an added input for situational awareness, but reported altitude and latency can cause confusion. Adsb targets recieved direct from a receiver or via being rebroadcast by the EFB provider have altitudes referenced to 1013mb. This means you need to add 30ft per mb difference if your local qnh is greater than 1013, or subtract if it is less. Targets recieved from avplan traffic live (same with ozrunways?) use gps altitude and therefore are closer to your qnh adjusted pressure altitude. In summary, be careful not to place too much precision on the reported altitude. Latency from adsb targets recieved direct from a receiver are the lowest; those from rebroadcast adsb or avplan live are the highest and highly variable. Tens of seconds or even a minute is not uncommon. My suggestion is as soon as you deduce a target is potentially a problem don’t wait too long before you act. Either get on the radio or take early evasive action. Franky

Yarrum of course!

It looks like the SSB batteries are all Lithium Ion Phosphate not Lithium Iron Phosphate batteries They are very different beasts. Franky

Hi Bruce The ETX680 does have cell balancing circuitry and other stuff, see excerpt from manual below. I think the problem is that there spec for minimum charge voltage is a little low. ETZ - BMS All EarthX integrated BMSs continuously monitor each cell’s voltage as part of the cell balancing and over-charge protection. If the voltage of a cell exceeds the others, the BMS circuits will work to reduce that cell’s charge level. This ensures that the charge level of all the cells remains equal, even with the high discharge (> 100Amps) and charge current (>10Amps) of your vehicle. A cell can be permanently damaged if over-charged (over-voltage) just one time. The BMS has circuitry to disconnect the battery from the charging system (plug-in charger or your vehicle) if the voltage exceeds 15.5 volts (an over-charge condition). The ETX Hundred Series batteries have enhanced over-charge protection; see the ETX - Hundred Series section below for more details. The ETZ BMS has short circuit protection, but it is not resettable or repairable. ETX - BMS The ETX series BMS has all the features of the ETZ series, plus over-discharged protection (completely draining the battery), excessive cranking protection, and short-circuit protection. The BMS disconnects the battery from the load if it is drained to less than 5% remaining charge (an over-discharge condition). An over-discharged battery typically has a voltage less than 11.5V. If the BMS disconnects the battery, the voltage reading of the battery will be zero volts. Excessive cranking protection logic includes temperature monitoring to limit “high current use” (engine cranking) to 10 -30 seconds in any 60 second period. If the battery terminals are “shorted” (or a low impedance load is connected across terminals), which causes the battery volts to instantaneously drop to a very low level, the battery will disconnect from the load to protect the cells and BMS from damage (short circuit protection). If the BMS disconnects due to excessive cranking protection or short circuit protection, the BMS will automatically reconnect after a cooldown period (typically 1-3 minutes). The ETX series is designed for short circuit protection > 1000 Amps. Franky

A few observations on EarthX batteries, specifically the ETX680 This was installed in an aircraft with a 912ULS and standard regulator mounted on the cockpit side of the firewall. The fault line was connected to the EFIS so any fault condition was immediately apparent. Not long after install a fault condition was reported which after consultation with the manufacturer it was decided that the fault was indicating that the cells were not quite balanced. The suggested solution was to charge the battery at a slightly higher voltage (14.2v) instead on the 13.8v which was output from the rotax regulator. The battery was removed and charged at the higher voltage and the fault disappeared. I decided that because the charging voltage was on the bottom end of the spec (13.9v to 14.6v), that the charging voltage on the rotax regulator would be increased to 14.2 volts. At this increased voltage there have still been 3 occaisons over 50hours of flying where a fault has been indicated, but the fault condition soon clears after 5 or 10min or so. Possibly a slightly higher charge voltage would stop this but I havent bothered. My suspicion is because of the cell balancing circuitry, a higher charge voltage is beneficial in helping the cell balancing operate. ( no higher than 14.6v of course) Although the manual says “no jump starting from a car battery” the warranty section clarifiies no jump starting from a battery of significantly higher capacity. It does not rule out jump starting persay. This indicates to me that jump starting from a small lithium powercube would not be a problem. The battery cranks the rotax so well I think more care needs to be taken in choke/throttle settings so that as the engine fires up excessive load is not placed on the sprag clutch. As an aside, when the battery is partially flat, the battery charge current in the above environment is about 8amps. Under this condition with all the other loads the regulator temperature reaches about 70deg on a 25deg day. (regulator output approx 18amp under this condition) Very happy with this battery, saves a few kgs, fantastic cranking regardless of ambient temperature; except of course for the price, although it is supposedly lasts a lot longer. Franky

I have had a stratux installed in my RAA LSA for about 6 months. I was prompted by seeing an increase in the number of GA planes who have adsb out over the past year or so. (using flightradar) I have had about 6 instances where see and avoid was inadequate and the adsb paint enabled appropiate action to be taken. It is a better solution than any method that relies on adsb receiving ground stations because you are receiving the signal directly from the aircraft with accompanying lower latency. You have to be careful interpreting altitude data because it is based on standard pressure and needs to be adjusted for local qnh (hint to bevan) Although most RAA aircraft (except mine) and many GA aircraft dont have adsb out, it is just another tool that does not replace see and avoid. It is especially useful at busy airports which have RPT aircraft and therefore will all have adsb out. Also good when near airports and flying VFR routes. I wish casa would make the fitment of adsb out to aircraft more economic by accepting gps sources with lower integrity. Franky