RFguy

You're not considering that if the GPS antenna  cant see a considerable portion of the sky, errors can be significant.  200-300m easy. That goes for ANY GPS, doesnt matter how good it is. If it cant get diversity of SVs (spave vehicles) , it will result in  poor transliteration solutions.

"Every consumer GPS I have seen calcuates its own potential error" - YES, HDOP and VDOP some only show HDOP, most consumer stuff wont show VDOP, and also, there is a stat associated with this number. Different engines report different stats (IE % confidence that the displayed fix is within xyz) 

""Just confirming I have got this right; there was a 1500 ft vertical error in the GPS position sent from the Skyecho  ?"

YES that easily can happen. I have seen up to 500m error.

Skyecho can be TERRIBLY inaccurate- the GPS  antenna has a terrible look at the sky in general and can be hundreds of meters out in any direction....

It depends whether the accuracy metrics from the skyecho are interpreted, or not.

Same could be for a tablet GPS

accuracy is transmitted on adsb, but many apps like FLight radar, flightaware  ignore these values, also.

AND  when route flying, ideally should be flying (with validity period) AREA QNH. 

Skyecho does know baro pressure. - IE absolute pressure. just like a normal transponder.  Ozrunways I am pretty sure says GPS altitude. 

When I have been flying through busy routes  6k-10k feet with other traffic around, ATC always provides me Area QNH to set my altimeter to (they request) . This way, we're all flying withing 50 feet of where we should be for separation.

Well. I just found a  small mudwasp  nest up behind my Directional Gyro !!!!. way up behind everything.....A  1/2" cube of mud....

During the annual , we found one fuel tank breather was partially blocked with debris..... 

For anyone interested, I have found a new perfect replacement for the display for this autopilot .

Backlight function is OK . Display contrast is good and is a transreflective display so it  can work in full sun.

Fits just fine, just reverse the standoffs  (order = SCREW > washer > plastic standoff > PCB ) and put the display against the panel. 

chop/ disconnect pin 1 on the connection (backlight aux ctl)

Display is a NMTG-S12232CFYHSGY-10  by Microtips, AVBL from Mouser.

You'll need either magnification or a microscope to change the LCD over since the flex cable is 1.27mm and quite tight on spacing.

The locals tell me they overfill the tanks daily and spit fuel out the breathers which kills anything living in there....

Jabiru's are readily repairable by those moderately competent with fibreglass. 

Carbon fibre is NOT, it requires specific layups and (usually) ovenized, resin cures , and an non factory repair likely requires a ultimate load stress test. 

You dont get something for nothing  (IE super light weight for no down side ) 

and just remember, for a given load factor, the slower the stall speed, the slower you need to fly in anything but super smooth air.

A 140 kts indicated aircraft is not much practical use if it needs to slow down to 72 kts in moderate turbulence. 

Skippy said "I would speculate that laser v punch likely have diffrent metallurgical outcomes "
Skip you are fantastic at stating the obvious. You should go on Mastermind and give Barry Jones a run for his money.

Certainly there is heat treatment going on.    The internet is full of stuff on this- all metals LASER cutting leads to substantially reduced fatigue life compared with other (cold) subtractive processes.... there are advanced post LASER cutting heat treatments but they are exotic.

I dunno if you can blame them that much for this.  If it was to get volumes up, not prices down.

More interesting, what's the issue with the laser cutting ???? That's interesting. I gather prior kits have been stamped/ punched ? 

I'd say I was fortunate  that I had a headwind, which slowed down the transition of descent , to following the runway up-slope .  Although that has to be traded off with the hazard of the abrupt wind gradient .....but I was anticipating that one...

Try to to do this though with a shorter runway, say half ,  well that would have a high degree of skill and danger, not for me.....

Certainly, a hazard checklist  is a good thing. I can see how this though is rolling a dice.   if you didnt think about it before you tried it, that could be trouble.

A couple of years ago there was fatal nearby to here (Combing Park)  - a fatal GA accident , was a training touch and go, where they attempted a go around with a hill ahead just like this one and crashed.  The report concluded they tried and failed to outclimb the hill. I am beginning to think , it was as simple as they just didnt think about it , before doing it , didnt do the numbers and consider the possibilities.  IE not a flying skills problem, a decision making problem.

Bush strip today. 650m long. DA=3000' OAT 6 ....Piper nice and light today. Deep valley  at the approach end, obstructions at the other  end, top of windy hill. half of runway is 'uphill' at 5% ! rest is 1%.... 

all in the lee of a big mountain , lots of turb. but turb was OK once I slowed down in the vicinity,  90 kts 1st stage flap.

I calculated the hell out of it before setting out.   rehearsed a few scenarios in my mind.  final was into 15kts I guess  wind .. Landed into the ~ 10kt wind, on the uphill section about one third off the way in. (on the steep bit) . no issue. Experienced high wind gradient as got into the flare and aircraft went below the top of the hill - experienced down draft as I got near the ground and also sudden 8 -10 kts ish loss of airspeed (as expected so I came in with 10kts to spare) . I had done a PSL immediately before on it so I had some idea what the wind was doing over the hill.  complex.

nose down , jesus the end of the runway and obstruction  is coming up brakes on ...... and taxi , hmm with 300m to spare, (used half the runway) . so that was good. 

Went for a walk with my GPS and barometer to meausre height one end to the other...., measured strip length and surveyed the height and gradients and estimated tail wind speeds at different regions for takeoff downwind. Determined a 'decision point' .   

....wind now 15kts minimum.  on my tail. 

Did what I needed to do at the site, back in the plane.... went off with a short fielder , 25 flap..... got past the decision point with only 55kts. geez we use up runway fast with 15 kts of tailwind ! Back pressure and now flying but not climing, still acceleratinginto ground affect, flying down the hill. golly does the  speed build.. climbing....  75 kts time to dump some flaps.. 85 kts, dump last 10 deg.  climb more ....  off we go.  

Colleague made an observation that the other hazardous thing about taking off downwind AND  downhill is that once I climb from the 'sheltered' region where I have say 10 kts of tailwind to where I suddenly have 20 kts of tailwind, and consequently 10 kts less airspeed, that is potentially hazardous and a good reason to continue to accelerate to and beyond  the T.O.S.S  in ground effect flying down the hill to have plenty in hand.....

Go around probably couldnt be done if it was hot.  photo of hill.... doesnt look like much but  downdraft from wind over the hill and hot weather would be trouble

looking downwind, and down hill. You can only see HALF the runway before it heads off the side of the mountain

. 

uphill , and upwind.  Top is 500m away from strip end. needs greater than a 1 in 10 climb to get over it. 

yeah if you are both connected to the radio and you can both talk OK on the radio, then all the connections are OK,  seems odd, will have to read the manual later.  I have one to install in the next week or so.

good stuff.

Sounds like the SIDETONE etc in the intercom setup is not right. You are using the TRIG internal intercom, yes ?

Suggest gettintg them on the phone, or going down and seeing them in person.

yes.... An IO-360 is pretty simple and reliable...

I would not buy a fuel injected Rotax product. I'll leave it at that.

here's a good example of a busy rotax...

https://www.facebook.com/groups/796324257055294/permalink/7003877179633273/?sale_post_id=7003877179633273#

Nev are you talking  about holding some power in the flare to slow the whole  transition down  in gusty condix instead of power to idle in the flare when in benign condix ? Certainly to fly and down a wheel down first, I am not sufficiently skilled yet to (quickly)  put the aircraft wing down on one wheel in one  flare movement at IDLE..... I will fly it under some power into  the wingdown, one wheel down  flare in Xwind.

Same goes for straight down the runway gusty condix, I will fly maybe half flap or no flap with some power on to slow the transition down..... In EFATO, well you dont have that option so its all going to happen quick anyway. 

It's not unusual to find a 1000 to 1999 hour rotax you can afford which has plenty of good hours on it and put a big bore kit on, (yes aftermarket)   There are a couple of major players that have variations. Mark Kyle  might chime in.....

An inflight adjustable prop can also get you a bit more ability.... worth quite a bit of HP for TO and climb I think.

Read the heavy maintenance manual of the series, also (both the MML and the MMH )  to get some engine background.  If a rotax is specified then a Lyco  might be too heavy to go with a Lyco. depends.... There is plenty to learn, find your way around the internet, lots of enthusiasts doing big bores, turbos etc.  Much to learn for sure.  Of course, as soon as you go away from the out of box crated item, you are a test pilot, which doesnt bother me for certain uses, but just saying.

Turbs, and J170C as you probably know did get a ventral fin to improve the tail authority. I reckon that aircraft might have been too much 'she'll be right'.  Tail- yep, same with LSA55.

ALthough - I think,  if you can fly those airplanes which are arguably less forgiving than the Piper, it puts you in a place where other planes are easier, or at least "better different". Those planes are very much lower inertia, I feel there is more scope to muck it up in the light, slow flying , low inertia airplane in the landing phase. 

"Hours and lots of experience help, but do not guarantee the sure outcome in a risky situation we might expect and hope for. "
Well said Nev. 
I wonder how many low altitude stalls occur with abrupt OR swift creeping  pulling the nose up in a 30deg banked  turn. In a banked turn, it's not as obvious the nose is pointing at the sky unlike straight .  Even if you have 'good airspeed' for the turn. If you pull the nose up (with plenty of airspeed) , it goes into a stall because you exceeded the AoA (and die) . I think that's not particularly well understood IE 10 knots above stall for your 30 deg banked turn is not a guarentee of safety.

Again, pulling back on the stick is the problem. In the EAFTO  and turn situation, lots of sh1t going on,  this might be a good time to have an AoA alarm.  The piper has one, but it's next to useless as it dimmly lights on the far left when it needs to be routed as a woop-woop into the audio system. 

"It's a little like learning to fly within RAA because "it's cheaper - advice given time and time again on this site, but by the time the student has to learn to fly the less-developed Rec aircraft the extra hours load up, and then there are the extra hours learning GA system and procedures to the point where without some luck it's cheaper to do all the training in GA to PPL."

That is not true. Little difference between the Brumby and Jab I learned in and the 'big '  Piper I now fly. I did have an instructor that taught like it was GA.... So I had zero extra to learn to fly the bigger airplane in complex situations..... The Instructor makes alot of difference.  I do know RA people who I think fly and do stuff like they got their licenses out of a corn flakes packet.  But I also have seen GA people do some poor airman's ship things.

go with a big bore 912(low compression)  and a afterthought turbocharger.  Or if you are scared of heights and heat , just a 912ULS with big bore kit.

Jab Gen4 is OK, also ,  but not really cheaper than a rotax per hour.  so you might as well buy a medium lifed rotax if you have the cash.

If you have not much cash, you can get a 400-800 hour Gen2/3 Jabiru for peanuts  and rebuild it to new for 5k. 

BUT ! the aircraft nose weight requirement will drives things, also. Lycoming O-235 would be my first choice if nose weight was required.

Enter the term : AutoIgnition temperature (AIT)  (not to be confused with flashpoint) ... OIl has a lower AIT  than gasoline.

Doing some reading, the autoignition temperature is probabalistic- to get reliable ignition, for gasoline LIQUID , you must be miles over, like 2x the AIT to get reliable combustion - around 580C  for gasoline. 450C for engine oil approx.

(ignition is where the rate of gain of heat is positive) 

The AIT for varies for varying  surface area to volume ratio is high (IE vapourized), amount of oxygen, pressure, turbulence  etc etc etc  . Someone here will know this stuff better than I . Please chime in. 

in my experience,  hard to get a fire if a little fuel drips on a exhaust or manifold,With oil, I've only had lots of smoke (vehicles). But, it's probabalistic, get enough action and it will ignite if above some temperature.

The AIT definition is temperature that  ignition occurs  at normal atmosphere and the state for that material in that atmosphere (ie liquid for gasoline, oil )  

excellent comment ! OK there it is : dont forget to re-calc /measure the W&B 

https://www.firefree.com/fire-retardant-fire-resistant-paint-products/ff88-intumescent-coating.php

https://www.firedefender.com.au/pdf/TECHNICAL-DATA-SHEET-AU-FINAL.pdf

A couple of things- the fibreglass going above its glass temperature will quickly lose its shape/strength. The fire guard stuff might be useful to prevent the fibreglass itself catching fire.

Others will no doubt have some experience here.