RFguy

I suspect a few high profile failures at this stage of market penetration could be curtains for UL, unfortunately. Yeah, Jab engines with Jab factory props (whether wood or composite) give a statistically insignificant number of reported problems. Ever seen the big bearing at the front of a lycoming ? a few inches long ! There is a reason for this... Jab also put alignment-fixing dowels onto the crankshaft-prop flange sometime around 2013, also. So something must have been amiss that we didnt hear much about.

I'd absolutely suggest using a Lyco or a Conty. The UL while similar to the Jab, it doesn't have much case time compared to the Jab which hasnt changed in the bottom end for a long time..... Jabs bottom ends dont give any problem unless their thru bolts break or are not correctly fastened (assuming initial assembly was good) . I'd suggest for others a low cost on-condition post TBO Lyco is still a better bet, if the aircraft can deal with the extra weight, which can be reduced with electronic magnetos, getting rid of the vaccum pump, lightened exhaust system, lightened rocker covers etc etc. I would be HIGHLY surprised if the Airmaster was suitable for the UL, since the moment of inertia is miles beyond the listed limit for the Jab engines, and the bearing setup is similar.

If I assume it is a normal category aircraft (3.8g) at MTOW, and the clean stall is 39 kts at 585kg, then the ATEC faeta ..... Va is 76 knots. (@MTOW J230D is ~92 kts) So you better slow down if you don't want to overstress the airframe. Saying that I would still like to own one of these aircraft for high speed, low cost commuting. anyway this forum is about the JABIRU SALE.

yeah adjustable seats are done by swapping out various under your butt + behind your back foam/cushion combos......

SKippy, Jabirus are fine. I think I have to slap you with those remarks. Push pull controls need very little maintenance. The whole floor , covers, and rear has to be pulled up in my PIper to inspect the myriad of cables, wires, pulleys, wheels turnbuckles etc etc Stall speed is fine. 40 knots is fine. ANything slower than that and unless your technique is good and you have a giant rudderm, crosswinds will be MUCH more of an issue for a pilot of average ability. Slow is not always good. Wing is fast enough and is very efficient. You will not go much faster than they do for a given stall speed and airframe weight . The Jabiru is about as good as it gets. sure could have a tidy up on gap seals etc, but it isnt much . Lower stall speed is an issue if you want to go fast because Va is proportional to stall speed. This means if it is ever bumpy, you will have to fly MUCH slower otherwise the aircraft will be overstressed. Sure yoru Faeta will cruise at 125 k, but it has to slow down to like 70 k if it gets bumpy !

yep, you can buy a 912ULS core for 28k. all accessories if you buy rotax (expensive) ones brings it to mid 30s, I think. But you get 2000 hours TBO without touching it , almost. Still , I don't hear too many gen4s blowing up these days, either. Hopefully, New Jabiru will offer Rotax powerplant for their aircraft. They'd sell alot of J230 hulls. They might outdo C172s.

update. on the HDX performing a CDI (course deviation indicator) function . using an ARINC429 interface (a type of aviation instrument bus) between a WASS GPS IFR approved navigator (like 430, 530, 175 , 375 etc) the HDX skyview is FAA approved for IFR for using the CDI function in the Skyview. That is, no discrete CDI required in that case. (according to the manufacturer in writing) .

well, an RPL and class 2 BASIC medical is a pretty easy conversion. This leaves the issue for aircraft that can fly at 700kg (J230) but are placarded to 600kg. and.. what are the pathways for uprating an existing factory LSA. Can it be done by re writing the placard and turning it into a 24-experimental via an MARAP ? (I wouldnt recommend at J230 > 700kg because I think the mains are not up to the increased landing speed energy having seen two broken now on others landing downwind)

I would think those numbers are within the normal range of the test precision. Sounds fine. If you get low leakdowns , WHY is just as important as the numbers to whether or not it is airworthy. Tank gurgles are normal. For a high hour 914, good numbers- nothing to be concerned about at all. Many rotax go 3000 hours+ without rings being done. Check if the leaks are happening on the exhaust valves- there was a SERVICE BULLETIN for 914 on the exhaust valves (in recent times) . Footnote- For Jabiru- Jabiru engine are not tolerant to brewing troubles like other engines. For Jabiru- Suggest investigating the WHY if leakdowns are lower than 70, and ground the aircraft if lower than 60. A leakdown lower than 60 on a Jabiru engine may indicate imminent engine failure will occur. (valves not closing (and will separate) , stuck/ broken rings, cracked piston)

And you wouldnt reach the pitch trim wheel in that condition in the 172...... (compared to rearward located trim in the Archer) .

KG- sounds like an ordeal you would rather not revisit.... So does the Cessna go that far back for what purpose ? In my Archer, full seat back would be still flyable, just a little bit of a stretch- Although I am tall and lanky so I have long reach....

interesting. I clearly have something to learn. so.. just how far do you end back if the seat goes back ?

hard to see how close the trees were. Better to run into the trees than stall. Assuming not a control surface failure (remote) : What's missing here is the basics- not pushing the nose down if the airspeed is critical... no matter what the circumstance. Must keep aircraft flying. no matter what . If time, turn the fuel and the master off. and cover your face with your hands as you go into the trees. Nothing much to learn here .. IMO..... (control surface failure aside)

Hi All, thanks for the replies and ops. Yes, certified. Otherwise I would go MGL in a pinch. Eager to foster competition in the space hence looking at non Garmins (nothing wrong with the Garmin, is the top kit) . Although I'll probably end up with a used '430 or '530 since they're very affordable.

Anyone used the Dynon HDX kit ? Looking for non Garmin options... -glen

but when you are up in the sky, another SE2 is all you need. (that and something to display it) There are quite a few applications that will display the SE2 data (GDL90 ) onto a map, not just Ozrunways. also onto EFIS screens via a wifi converter.

flight radar24 or flight aware flightaware has better server - system software. FLight radar24 has been presentation but more troublesome server systems, I have found anyway. Generally, you will upload to both from the one Raspberry Pi or PC. You need an internet connection you can use- the data usage will be bugger all, especially if you reduce the seensitivity so it can only see 20nm etc instead of 100 nm.

Do you have a local receiver for ADSB ?

HI OK, but the pulses are extremely narrow- IE the energy per second is miniscule. At 1m away, the SE2 will produce a peak level of about 1.6W/sqM, and a time averaged value of no more than 2.4mW/sqM For the record- let's look up the peak level for 1090 MHz in the latest ARPANSA STD Rev 1 Page 6 section 2.3 Table 5 Peak spatial 24W/sqM. We have peak of 1.6W/sqM . General public : Local Head and Torso - 2 W/kg. averaged over 6 minutes. Peak level cannot exceed 0.72kJ/kg Another way - Table 6 : 8.5kJ/m2 . The peak spatial is 1.6W/m2 (150uS) = 240uJ , a long way below the 8.5kJ Suggestion - keep it > 30cm away anyway- why - any less and your presence be affecting its performance. The head will soak it up. Permitted peak level will be exceeded at about 20cm. Levels fall with square of distance, so at 1m, there isnt much left.

Additionally- while the antenna may have its "ground plane" elements , anything conductive in the near field - that the antenna can see - anything conductive between the antenna elements - essentially bounded by the dimensions of the antenna- will become part of the antenna. Your only option is to move the antenna or choke or shields the cables. You could stop the antenna seeing the cables by providing the continuous conductive region (aluminium sarking 0.1mm is good) ABOVE the cables. The 'radiating element' of the antenna - in this case a whip - all the return currents will flow to the continuous ground plane as preference. gross example - a whip on top of a factory roof and feed through the roof- all the return current sflow between the whip and the top of the roof in the region of the antenna, no space currents are present under the roof.

Hi Geoff apologies, I should have written ' this is not always correct', rather than ' this is not correct' . My point is that it isnt a rule. In most control signal cases, like RS232, 485, CAN, earth or negative reference will be carried by its own conductor in a multicore, or on the shield. It MUST BE to ensure the common mode voltage is within limits- IE the voltage from either A or B side to ground or negative. or 'return'. Otherwise things blow up because the input circuitry is generally not galvanically isolated (layman : no DC path) . An example of galvanically isolated is across a transformer. There is no DC path . Shields can be connected to various things at each end. Shields are often connected to the same point the negative is. But not always There are some cases where the neg might be a separate ground in the device. Here are some examples : - the power supply pairs might go through a common mode choke or filtering, and the shield is connected to the metal box and not circuit ground , IE the negative is connected to the case via a choke, or via a high impedance- so that the AC impedance of the negative connection to case is >> zero. This is done in industrial settings to prevent UNINTENTIONAL return currents flowing through sensitive signal shields. IE a shield is usually a large conductor, and due to its lower resistance, a portion of heavy currents to a DC motor (or imbalance in a 3 phase system) might flow in the shield. In this case, only connect one end- as long as the multicore does have a negative return /reference assuming is DC referenced. For problematic systems, transformer isolation virtually eliminates ground. earth loop issues because a negative return does not need to be connected- the signals are purely referenced to each other and never to ground . All this is relative to the signal levels encountered. For dealing with moving coil microphones with signals ~ 20mV, small parasitic currents in shields and grounds can generate a few mV of interference. But so say, an RS232 signal - +9, -9V, , that few mV of interference wont matter at all. That's fine for DC and low frequency AC When it comes to HF/ VHF RF AC, its a difference ballgame. In high RF environments, shields on multicore signals at both ends are a must , and generally the cable shield must connect to a device shield of the device, whether a metal box, or a PCB ground. When an shield is connected at one end, the RF will run on the outside, then back on the inside of the shield and couple to the internal cores. Long cables- the RF that gets on one end of the cable, say where the cable shield is device shield, the RF energy that gets on the outside of the cable , if long, may be substantially diminished by the time it gets to the end that does not have the shield connected, and not matter- this might be several wavelengths. There are some corner cases - If the shield is connected at one end and the shield is an odd multiple of a quarter wave at the frequency of interest, it will become part of the antenna system , but it may not if both ends are connected ! - multiples of quarter waves and half waves come into play here and the equivalent circuit becomes complex. So best method is to connect shields at both ends to stop the RF on the outside of the shield getting back on the inside. If the cable shield is connected at both device shielding ends, no RF can get into the devices -glen

Hi Mike OK so CANbus to the servo. In this case. and considering you have other CANBUS items, then just brute force shield everything IE all items in shielded cables. foil is fine at this frequency although broaded is preferred (or partial briad and foil) . What is probably happening (I do know a bit about CAN) is that the driver is self locking out when it detects that condition- its used on CANBUS to avoid a sick controller jamming up the whole network. If brute force shielding is too hard , Alternatives if you have access to rear of connector : Now another option for you , and which one somewhat depends on the precise mechanism : 1) two x 100pF disk ceramic capacitors from CANBUS A and B line to the ground / take it to the neg of the connector or servo body. That should kill the induced energy, take it to ground 2) It's possible that you could end up with alot of energy in those caps. check if the VSWR changes after you have done this mod. non intrusive ALTERNATIVES 3) Additional benefit would be an RF choke ---- this would be feed the CANBUS feed through a few ferrite beads, or split beads. you'll probably need at least 3 to 5 to make a dent, close to the servo. and put them on the other devices, also. and also put a coupl eon the MGL controller end. and put a couple on the COAX of the radio antenna. https://www.ebay.com.au/itm/354863733597?mkcid=16&mkevt=1&mkrid=705-154756-20017-0&ssspo=cjibypsiq0a&sssrc=2047675&ssuid=&widget_ver=artemis&media=COPY https://www.ebay.com.au/itm/124994863518?mkcid=16&mkevt=1&mkrid=705-154756-20017-0&ssspo=SHweELfzT1y&sssrc=2047675&ssuid=&widget_ver=artemis&media=COPY that 9mm ID and 5mm ID. use smallest that will clamp easily. also available in large IDs. You might need three in series to make the difference you need. works betwen with the caps in (1) you can use the chokes every 60cm or so and should prevent the antenna getting any energy into the wiring... (inserts a high impedance in series with the cable) . I gather this : https://www.mglavionics.co.za/Docs/Servo user manual.pdf so not so easy to put the capacitors (caps) in. Suggest some split bead ferrite cores, in that case. when used with (1) , the beads will work more effectively. -glen

" A cable shield MUST be only earthed at one end or the conductor inside can get all sorts of funny voltages appearing. " This is not correct.

mmmmmm. what is going on here is that the motor servo driver is getting RF into it and likely causing a cross conduction and thus a fail. the pitch servo sounds like it is in the near field of the antenna . From memory most of those servos - the motor driver is in the main unit, so only motor currents are on cables. The antenna is injecting current into the servo system because it is part of the antenna. What you need to do here is run the cable to the AP servo in a shielded cable. Attach the shield of the cable to the body of the servo motor. I'd suggest not connecting the other (AP controller) cable shield end at least to start. If you wrap the existing cable in copper or aluminium tape (again, connect shield to servo body) , you can acheive the same thing. The shield needs to extend at least two x the antenna dimension. What though may also happen is that this might affect the antenna . Avoid shield lengths that are an odd multiple of 60cm +/- 15% . IE make the shield 120cm or 240cm. What AP servo / AP system is it ? Glen.

Hi Nev. accordingtto the spcs, carries 101t of fuel...... 787-900 : MTOW 254t . max landing weight : 193t. max zero fuel weight : 181t ... fuel : 101t .....