Nobody

The average of the speeds is not correct. It is close when there is little wind but is wrong at higher wind speeds. Take for example an aircraft with a perfect ASI. Say it can fly at 100 knots indicated air speed and the owner goes out to do the calibration on a day where the wind is blowing at 50 knots from the north. When he flys north he will have a ground speed of 50 knots. When south he will have a ground speed of 150 knots. To fly directly east he will have to fly at a heading of 060 and have a ground speed of 86.6 knots. To fly west he will have a ground speed of again 86.6 knots and need to fly at a heading of 300. The average is (150+50+86.6+86.6)/4=93.3. Now I accept that this is only a 7% error for what is quite a high wind but even with more normal wind at the slower speed that raaus aircraft fly this can be significant. The other advantage of the spreadsheet method above is that you do not need to be exactly on track and they don't need to be the cardinal points. Any ground speed and track works as long as they are in different directions. Greater accuracy comes when they are evenly spaced around the compas.

It isnt quite as simple as averaging the ground speeds to determine the true airspeed. You need to work out the wind vector and subtract that(in a vector subtraction sence). For a small amount of wind relative to the ground speed. The method is described in the links below. Method description http://www.ntps.edu/images/stories/documents/gps-pec-method.doc Link the Spreadsheet http://www.ntps.edu/images/stories/documents/gps-pec.XLS Assuming that your directions above were ground tracks and not headsings when I put your numbers into the spreadsheet get a true airspeed (based ont eh gps numbers ) of 82.4 knots and hence would conclude that you ASI is out by approx 7.8 knots at that speed. It seems like a pretty big error.

you can also get it here but shipping can hurt: http://www.steinair.com/

If this issue just happens and didnt in the past also check that any filter (if fitted) isnt starting to clog up. Many of the automotive type ones can be poor in this regard.

Pretty short sighted to rule out vh reg aircraft.

Jabiru do. See here: http://jabiru.net.au/engines

I wonder if you guys would be so flippant if you realized where the money for this is coming from? If the pilot is sued and loses will the RAAUS liability insurance be paying out? What will the premium go up by so that the insurance company can recover their costs? If there are 10,000 members this would be $75 per member.

Have a read here for the restraint/legal issues. https://www.casa.gov.au/sites/g/files/net351/f/_assets/main/download/caaps/ops/235_2.pdf As Jay pointed out most car seats are ok. As per the CAAP you may not need the top tether.

Awesome!!!!

https://www.aircraftspruce.com/catalog/topages/cobaltdrill1.php?clickkey=9022 http://www.cleavelandtool.com/Plastic-Laminate-Drills/products/22/ I use these to drill canopies/windscreens. Light pressure, high speed. Holes look great.

Raspberry PI based ABS-B 1090 MHz receivers have been around for quite a while I first had one about 18 months ago but they were availalb ebefore then. They are able to display the position of ABS-B out equipped aircraft on a computer or Ipad running ozrunways or I think AVplan( I havent done it one avplan but think that it can) What this one does that different is 2 things that are usefull if you are in the USA but significantly less useful if you are in other parts of the world. 1 It is able to decode the weather stream that the FAA broadcasts. This provides in flight METARs NOTAMS, Weather radar and other useful weather information. 2. It works with Foreflight. Now foreflight is a very common aviation app in the USA. It is like ozrunways but better in many ways. They developed their own ADS_B reciever called Stratus and charge between $550 and $900 for an all in one package that has the capabilities in your link. Because they had a product to sell they didn't support DIY options. Recently people have worked out to make the raspberry pi "look" like their commercial stratus and so it can be used with foreflight software. Unless you use foreflight in Australia (and without maps or naips integration why would you?) there are better things that form a similar function out there.

Sorry FT it is hard to work out which bit you have copied and which bit you wrote but are youo saying that you have built one of these and are gtting the FIS-B weather on 978 MHZ in Australia? I wonder what/who is broadcasting that if you are? If all of the post was copied from someone in the USA then a better option for Australian use is: http://adspi.ozrunways.com/

In many ways I think that this thread explains some of the engine issues that Jabiru have had. For some reason many of the owners of them feel that the weight limits in the POH don't apply. I wonder if people apply the same logic to the CHT limits? I am sure Jabiru would have increased the weight limit of the 160 to 600kg if they could.

here are the speed numbers from the POH for both the J-160 and J-170. Note the fairly significant difference between the two with regard to both maneuvering and stall speed. Also not that the J-160 number are for its MTOW of 540kg. The stall speed will increase by approx 5.5% in going from 540kg to 600kg.

Isnt the J-160 540kg and the J-170 600kg?

I dont own a Jabiru Aircraft or engine but have spent a lot of time looking at them and talking to people who currently do and perhaps my next aircraft will be jabiru powered. Peoples view on Jabiru are polarized into two opposing camps. To understand this you need to understand what Jabiru have done. They designed, developed and marketed one of the best small aircraft airframes ever to fly. They however put in it an engine that is only OK. It isn't bad(there are many "aircraft" engines that are much much worse) but it isn't great. When the aircraft was originally designed they were going to use someone else s engine. That engine faced delay's in being ready and they were forced to develop their own engine. The engine has some good points, low weight, good power, simple oil system but is sensitive to overheating. Engines that have been overheated tend to have onset detonation issues and dimensional issues with the heads in the longer term. The overheating comes down to a few points. Some people run their engines that little bit hotter, some live in hotter locations and there is some variability in the setup of the baffles in individual setups. The acceptable temperature limits published by Jabiru are probably too high to be acceptable. What this means is that some people never have an engine issue and swear balck and blue that the Jabiru is the best aircraft ever. Other people are overhauling engines every few hundred hours and, on their third engine cant wait to get rid of the thing. This isn't helped by Jabiru's approach to customer service. To the people who have problems they point out that there are many others who are getting good service out of their engines so the customer must have done something wrong, bad maintenance, incorrect operating, poor fuel. The customer says "but I operated it within the limits you had in the manual." Both statements are true. This also hasnt been helped by Jabiru's approach to development. Over time many little changes have been made to the engines. When people have an issue with an engines Jabiru's response has been to offer a overhauled engine with all the upgrades for eg $10k. Now some people think, "Greet, A new engine for half price". Others think, "I paid $20K to buy an engine and this one failed halfway through its life and now you want me to give you more money" Jabiru engines are in this halfway house between a fully old school certified engine like a lycoming and the wild west of full experimental. This allows their factory built aircraft to be used from training and hire. Jabiru engines have been demonstrated by the manufacturer to meet the ASTM standards by testing in a test cell and that was the case in the early days. Following the design improvements this testing hasnt been repeated. CASA got wind of a number of failures and had a chat with Jabiru. Their response was along the lines of "don't worry, we have fixed these issues". CASA's response was "while that may be so you haven't demonstrated that is true in a test cell and how come you have made changes without updating the paperwork." Overall a Jabiru aircraft is a reasonably good aircraft. Anyone who says what your original thread title said is an idiot. Their weakness is engine cooling. Anyone who flys them without temp monitoring/recording on all cylinders and doesn't keep well within the CHT limits is also an idiot.

I suspect that you haven't tried to run a cycling event, swimming carnival or play rugby on council land recently. Almost all of these events the council will charge some type of usage fee for the use of the facilities. And or require that you have (and prove you have) public liability insurance. I would also add that being more diplomatic in your communication is more likely to get a good outcome. Councils don't just one day decide to introduce landing fees. They have a budget issue and look at their operations to try to raise revenue. If they don't really know what goes on at the airfield it is easy to add a charge to it because the backlash will be minor. Users of airport need to be much more involved in selling the benefits of an airport to the local community. This is where airport user groups when well run can have a very positive impact on the long term stability of an airport. Another important area is community awareness. Look at the EAA Young eagle program. It is a great program for introducing the general public to aviation and particularly experimental/the small end. What it also does is prevent the introduction of landing fees and the closure of airports. Who wants to be the councilor that votes to stop the kiddies fun? After draconian over regulation, Airport access is a key issue for the future of General Aviation in Australia. Sadly RAAus, SAAA and AOPA are all missing from the discussion/fight.

number 5 no?

According to page 16 of this document it is $250/t MTOW per year and is an annual fee for regular users so $150 for a 600kg jabiru. http://www.corowa.nsw.gov.au/council/planning/fees/images/Final_Revenue_Policy_2014-15.pdf EDIT this document shows that it has doubled for next year: http://www.corowa.nsw.gov.au/business/development/images/2015_-_2016_Revenue_Policy5.pdf

It is actually worse. The table lower down the page shows that in 2011 there were 10528 members. 1411 member lost at about $200 per member is $280k. Thats a few staff right there.

If an airport is seen a a drain on the resources of a local community then the likely next step is landing fees if not closure. Access to airports is likely to be the biggest thing preventing the expansion of recreational flying and not just in the major centers. If you have an airport locally but nowhere to fly to then the fun and utility of having an aircraft is much reduced. If you operate at an airport where there are currently no landing fees you need to be talking to the operator of your airport to explain the benefit to the community of having an airport. You need to be helping them plan the future of the airport and being involved. You want the Wollongong situation rather than the Warnervale one. I bet that in the Corrowa example above a year or so ago there was a discussion paper of some sort about introducing landing fees. How many comments against it did they receive? Waiting until one day when they introduce landing fees will be to late. It is much harder to change a decision than to prevent one being made.

I don't necessarily think when comparing an RV-6 and a jabiru you need to remember the speed difference. A jabiru will be cruising about 115 knots and the RV-6 about 160. This means that when the unfortunate incident occurs the structure has to dissipate nearly double the energy. More if you account for the weight difference.

What you possibly saw was Stress Corrosion Cracking(SCC). It is a known issue in certain materials in certain environments. In bolts greater than about 1000MPa tensile strength is it possible in an atmospheric environment. Lower strength materials are less likely to be affected. The academics tend to argue a bit on the exact mechanism however they agree that it requires, stress, a susceptible material and mildly corrosive environment. One way it has been explained to me is that a small corrosion pit forms. This causes a stress riser increasing the local stress. This higher local stress causes the material to become anodic compared to the rest of the material accelerating the corrosion. The increased corrosion causes a higher stress concentration and relatively quickly a crack progresses. There are other descriptions of the mechanisms out there too. An AN bolt has a strength of about 880MPa and so would generally be below the strength susceptible to SCC. 12.9 and 10.9 grade bolts are used in the automotive industry are above the stress level where SCC may be an issue. If the bolts are used internal to an engine or gearbox then there is no corrosive environment and the bolts give good service. Also is a bolt is installed in an car with the correct type of corrosion inhibitor than then never removed for the like of the aircraft then there is a low risk of failure. Using Automotive bolts in an aircraft application where removal in installation is likely over the life of the aircraft and the bolts are not installed with the right type of goop is likely to lead to failures. This is one area where higher strength in not always better.

You say you are worried about the perception of flying being dangerous and how that will cause your other half to prevent you from flying. And yet you defend a hyper sensationalized thread title that appears to have no relevance to the actual circumstances of this event?

Just thought I would add a link to this write up of a camera affecting the stall speed. If you do go ahead and mount a camera (either with or without approval) give some consideration to where and how you mount a camera as well as how you plan on flight testing. Be particularly careful with anything on the top of the wing or any where on the aerodynamic surfaces of the tail. http://www.vansairforce.com/community/showthread.php?p=888927&highlight=camera