sfGnome

My vast(??!!) experience of the younger folk is that they're all different. (Amazing, really). My younger son is simply not interested in coming aloft. My daughter came up once to keep me happy. My older son was keen, but after a bout of airsickness his keenness diminished somewhat. Just about to give up on the lot of 'em, when recently I took my son in law up. "Wow. Awesome! This is amazing. My dad is going to be soooo jealous". Looks like I finally found one with the nascent bug... :)

I had an 'interesting' moment fairly early after getting my X-country endo. Heading north into a strong headwind, crossing an east-west mountain range, I only left a bit over 500' ground clearance. Approaching the range, she started descending at a fair rate of knots. I was on the edge of chucking a U-ey when it flattened out and I could climb again, but I've always approached mountains with a lot more respect (and a lot more clearance) since then.

That's a pretty impressive "least impressive"... :)

I generally include a comment in my briefing about some "really stupid" passengers who've let their feet get near the pedals. That seems to do the trick... :)

Thanks for asking the question. I'd given up looking for it. I like OzR, but geez I wish they'd just write a few sentences of instructions on each new feature. It doesn't need to be big power points or anything, but saying "We've got feature XYZ" without explaining how you access it (or even what it is on some occasions) just isn't helpful.

Yeah weren't you the guy that scoffed and ripped into someone else here who mentioned this resignation a few days ago?An apology to her seems appropriate about now no?

Saw Robert Redford's latest flick tonight ("All is Lost"). Now *there's* a bloke who could have used an EPIRB...

Flew on Tuesday late afternoon in Victoria 40 plus degrees during the day. Sea breeze came in but still 30 plus degrees at 1500 and 2500 feet but the air was like glass with not a bump in it.Flew again Wednesday afternoon 37 degrees at 1000 to 2500 feet and still not a ripple in the air, climbed out at about 85 knots to manage the temps and never got out of the green

Surprised me how smooth the air was with such warm air temperature t these altitudes.

Nup, it's not Mt Beauty (I think!). Now if it's the next valley down, does that put it somewhere near Bright?

Took a flight in a glider today, courtesy of the good folk at Mt Beauty Gliding Club. Just a half hour (couldn't afford longer) to experience the feel of a very different aircraft. Much fun, but I think I'll stick with my motor for the time being... :)

The best part about this photo is that you can ignore the ugly sod on the right and concentrate on the beautiful bride on the left...

...And a merry Christmas to all!

Just a few test flights for a faulty - now repaired - Altitude Encoder. Of course, I had to take it up to 7,500', didn't I? Never bothered to do that over the home field before. Nice view.

Robots are how Google et. al. know all about everything on the web. Their computers, commonly known as robots, 'crawl' around the web, following all the links on a page and all the links on those pages and all the links... etc.

Mostly PC, but only because I can't get the little pop-up preview window on the iPad.

...I will need to visit my daughter in brisbane...

Thanks to you both.

Can I ressurect this thread to ask a related question? Our (*very* old) altitude encoder has curled up its toes and taken its last flight. The replacement choice from Australian suppliers when you're purchasing encoder only seems to be limited to the Ameri-King AK350 or the Microair EC2002. As our transponder is also Microair - and it's Aussie - , it seems to make sense to use it rather than the American unit. However, the Microair unit is not TSO'd. My understanding is that if a recreational aircraft is flying over 5,000ft, then it must have a transponder that has been calibrated within the last two years, but it is not necessary for the devices themselves to be TSO'd. Is that correct?

That's certainly the case where Ohm's law controls the charging current and there are no other constraints; this is usually the case with a lead-acid battery in a car. In that case, as you say, only the charger voltage matters - provided the charger voltage cannot exceed the fully-charged battery voltage, it can never supply more current that the back emf and the internal resistance of the battery allows. However, it is possible to damage a lead-acid battery that is close to fully discharged if the charger has more current capability than the battery can handle without physical damage - and Ni Cad aircraft batteries had to have the charge current regulated by the battery temperature. So it ain't necessarily that simple, I suspect.

What I do NOT know is (a) Whether there are constraints of that nature for the Ipad mini; (b) Whether there is protective charge control circuitry built into the Ipad to cover this - or whether it is controlled by limiting the output of the charger. An LT3083 can produce 3 amps. That's three times what the Apple-supplied wall charger can provide.Further, I don't know whether the 1 amp Apple charger can keep up with the device if it's on full brightness continually, as it's likely to be in the aircraft. So it's not a given that 1 amp is sufficient. I suppose it's a case of suck it and see.

For voltage and current, think of it this way. The source supplies the voltage and the load draws the current. As long as the supply can supply as much current as the load needs, then everything is fine. You could have a supply that is capable of supplying 1000A and it would be quite safe to connect to your iPad, because it is the load (ie the iPad) that controls the amount of current drawn. On the other hand, if the supply can't supply enough current to keep the load happy, then the voltage will droop and all bets are off. So, if your genuine Apple wall charger that came with it is rated at 1A, then it means that the mini iPad must require less than that amount, and any cigarette lighter charger that can supply that much or more is fine (all other previously discussed issues being already accounted for, of course).

Well, there you have it . . . .One small point could perhaps be (I'm speculating here) that many of the cigarette-lighter style adapters offer two USB outlets - which may be a way of exporting the "wasted" power and thus reducing the heat, provided a load is connected to each of the outlets; added to the liklihood that there's a thermal shutoff built into the things - which would mean that they will likely to be charging less than half the time. My reading of all this is that if your cig. lighter adapter is charging full-time and staying nice and cool, it's likely to be a switch-mode device, and therefore likely to be putting voltage spikes into your ipad. If it's getting hot & bothered & only charging part-time, especially if it's only driving one outlet, it's a "linear" type, and probably not putting voltage spikes into your ipad. The 2.1 amp ones for the ipad will be far more obvious under this crude test than the 1 amp variety for a GPS or whatever.

As Malcolm Frazer said, "Life was not meant to be easy". Why not use a pair of 6 volt batteries in series, and run an LM317K linear regulator from each of the 6 volt halves, for the ipad & GPS? That gets the waste heat way down - to about 3 watts, instead of 27 for the two outlets. I'm planning to build my own L-C filter for the 12V supply to the radio & transponder, including crowbar protection; ferrite toroids are remarkably cheap, and I have some 25 MFD 450 volt polyethylene film capacitors laying about . . .

The biggest problem with running a linear reg off a 6V battery is that linear regs require a certain level of step-down, and even the best ones will be borderline at 6V. As soon as the battery voltage starts to droop, so will the output and the iPad will start getting very iffy. Switchmode reg, on the other hand, will keep supplying as the input voltage droops (for a while at least).

That was really interesting reading. Thanks for pointing it out, Andy.

Just to add a little confusion (though hopefully not too much), I have to disagree with Andy's comments that the 12->5v converters are likely to be linear. The power dissipation (9W for a 1A converter working from 13.8V) is just too high for the cigarette lighter plug packs. They'll almost certainly be switchmode devices, running in the megahertz range. These high frequencies allow the inductor and caps to be very small, and they easily run at >90% efficiency so they're dissipating less than 500mW (and they're still as cheap as chips).

Their safety basically comes down to the components used, and to put a rough rule of thumb on it, the more expensive, the better. Why? Two factors. The first is that the switching FET - one of the more expensive parts @~20-30 cents) is subject to all the spikes that exist on the main bus, and in any automotive or aircraft system, they can be very large indeed. If the FET fails, it typically fails short-circuit, not open. That then puts the full 12-15V of the bus onto the 5V input on the electronic equipment. Most of the time, it'll blow a fuse (either in the equipment or on the panel), but if you combine it with the large spikes that took out the FET, they could take out the battery too (with extreme prejudice). Given that these spikes tend to occur at engine start and shutdown, it's wise to switch off the power to the converter before starting or stopping the engine (just like you always do to protect the rest of the avionics, don't you!).

The second factor (though it doesn't affect the battery safely) is RF conducted & radiated emissions. It's not hard to suppress the emissions from a power supply if you do it at design time, but if you're either slap-dash in your design or looking to shave every cent you can from the BOM cost, then it's easy to 'accidentally' leave off the components that make the unit meet the international specs. It is illegal to sell electrical equipment in Australia that doesn't meet the requirements, but if you're buying cheap (and especially if you're buying off the web), there's every chance it will radiate like crazy. There's no easy way to check this your self, but basically, if you use a converter and you start hearing noise in the intercom or radio, chuck it and go and get a better one. Life's too short to stuff around with making a $5 converter work in your system.

Bottom line? If you're powering your $800 iPad, don't use a $2 converter.

Just to wrap this up for future reference, on the weekend I spat on the suction cap before attaching it, and when we tried to release it, it was really hard to remove. Looks like that's the secret.

Colour me interested! The report from our mate who drove down (though I think he may have regretted agreeing to be the pax during an aeros demo) only whetted my appetite more. North is handy, but by no means mandatory; it was just unfortunate that the conditions on the day messed things. The sad part was that if bad weather was forecast, I would have driven down, but "light winds and CAVOK" sounded tailor-made.

As those of you not in Sydney and surrounds may have heard, we've had a few of a bushfire issues lately. Yesterday, we had intended to fly from Warnervale - north of Sydney - to Jaspers Brush - in the south - for the EMT course that the kind folk were running there. Unfortunately, prior to the entry to the western VFR lane at Brooklyn bridge, we hit a solid wall of smoke trapped in an inversion layer at about 1,500'. Yes, we were clear of it, but there was zero ground reference for navigation and zero opportunity to pick a landing spot should things go quiet. We shot over to the coast, but the smoke went far out to sea.

Figuring that it would dissipate as the morning progressed, we went back to base for a coffee before having a second go. Second time was even thicker. At the coast, we tried to descend on the basis that from 500', we'd have adequate visibility, but apart from choking as we went into the smoke layer, we also started to loose any horizon. Didn't hang around there, admitted defeat, and went home.

This morning, I was up at the Brooklyn bridge again, but this time on a slightly more earth-bound conveyance, and this is what it looked like. For those of you who don't know the area, this is about half way across the bridge, and there is a dirty great big mountain at the far end of it...

I hope the Emergency Maneuvers training went well, because the only emergency maneuver we go to practice was the 'Turn and Run'. Ah well, live to fight another day.