Ross

Hi Geoff I was visiting my daughter in Concord in August and was taking a few photos outside around the house when I looked up to see the blimp. So I got a few low quality photos whenthey were on the far side of their circle when I could see the programmable screen on the blimp but better qualityon the other side of the circuit. See photos below. This first shot was 10X but trimmedbut notenlargedas the blimp was at about 45 degrees south of Concord and a fairly good shot but got too far away after it did a 180 degree tun. [ATTACH]213[/ATTACH] In this photo below they can program the screen to display different scenes but this shot was a very long shot with 10X zoom and the pic was very small and has been trimmed and enlarged substantially so quality is pretty bad. [ATTACH]214[/ATTACH] Regards Ross

Hi Darren I have virtually finished the tail group except for high fill undercoat rubbing back around the horizontal stabiliser and end caps. This week I have lined the cabin area except for the firewall foam & felt and the strips down the side of the windscreen. I have moved my tail strobe power supply to the fuselage wall just below the rear window behind the pilot's seat. It should have less effect on the balance and be less subject to accidental damage from luggage. I have run the aerial down the other side of the fuselage. However they have not supplied me with felt & velcro strips to cover the fuel lines to the wet wings so I will have to organise that tomorrow. My wife does not think there is a velcro supplier in Leeton so I may have to get it from Wagga or Griffith. I have other felt to do the lining in the luggage area but will have to get more goo from my local carpet supplier. After that lining is finished I will install the windscreen and the back windows. The doors can be a fill in job and better to leave them off if rolling the aircraft over for undercoating rubbing back & final painting. Had a day off today with a drive to Deniliquin to have lunch with an elderly Aunt. That was from Leeton to Whitton, Darlington Point, Coleambally, Jerilderie [ATTACH]808[/ATTACH] Off the side of the bitumen road west of Jerilderie and east of Conargo NSW Au 20061002 and Conargo then Deniliquin. We returned via Finley visiting another Aunt then Jerilderie, Narrandera, Yanco then home to Leeton, total distance was 492 km. There was only about 7 km difference in the two 'halves' of the trip! Regards Ross

Hi Jabbers Thanks for all that useful info on draw strings, wing cut outs and exhaust systems. If we quoted serial numbers with this detail it would give us all a bit more information. My J160's production numberis # 014 and the engine number is 22A 1906. So I just got the new carby jets I think (I will have to check it) but not all the oil pump modifications but I get the new oil cooler. I had to install extra cabin reo along sides of the windscreen and from the whalebone across tothe door frames. My rudder cable holes were not installed making life a bit confusing. I think I have the modified UC axels and the old style round discs on the brakes which might turn out to be an advantage. I had tomodify the passenger seat top to install the new header tank which came with the kit. Regards

There are many considerations in engine design one of which is the back pressure of the exhaust system. It can havea big effecton the oil consumption of the engine. The more back pressure the less oil consumption and the less power from the engine. I used to wonder why the older aero engines had such a copious appetite for oil on engines with no mufflers and straight out exhaust pipes and no aircleaners compared to typical land based engines. So Jabiru have at least two factors that reduce the power from the engine. The first is an air cleaner that is even still in use when carby heat is applied which must cause some reduction of air in the firing cylinder. The second is some back pressure from the exhaust system. Both of these items will probably contribute to a longer engine life and a reduction in oil consumption and a reduced running cost. Jabiru and other manufacturers areobviously continually researching their engine to get more power from it aside from the normal targetof enhancing its mechanical life and reliability. There have been a number of changes to the oil pump and the oil cooler for example aside from other engine changes and improvements. For example fuel consumption with the Jab 2200 motor has supposed to have dropped from about 16 L/h to about 13 L/H due to letting the engine run leaner and hotter therefore more efficiently. They have increased the quoted HP from current models of this engine to 85 from the previously quoted 80 for previous models and have raised the TBO for a bottom overhaul from 1000 hrs to 2000 hrs with a top overhaul at 1,000 hrs.

Geoff I can see that I have not been keeping up with the necessary strategies to really nail this project.

I would agree whole heartedly. When flying the Griffith factory built Jabwith the radio at the bottom of the panel it is a real pain keeping track of the frequencies with your head down, not a good idea, and changing them. Howeverthey could all be preset in memory for a particular trip requiring just a flick of the switch to get to the next required frequency. Some radioscan have a remote button on the stick to cycle the preset frequencies. I haven't checked to see if this is available on my Jabiru supplied radio. As turtle points out ithe radiois probably, even for VFR pilots once airborne, the most adjusted instrument on the panel. So it does not make ense for it to be mounted at the bottom of the panel. I have moved mine up a bit and if it is not OK then I will cut another hole and make a patch to fill the gap. Regards

Hi Geoff K & Clem & Turtle I know how you feel about that target disappearing into the distance. At the moment I am doing the jigsaw puzzle of the cabin lining. Apparently the lining pieces were designed before the cabin reinforecements were introduced into the J series and the header tank under the passenger seat. As a result you have to think of where will the bits fit assuming there are no reinforcements. Of course they don't fit exactly so you have to cut holes in them and trim bits off here and there and also overlap them in some places and not in others. I was never very good at jigsaw puzzles. Apparently cabin lining does not include the top of the instrument panel or anything behind the seats except perhaps the sound curtain although it is separately listed. I can't really do the firewall lining (foam & felt) without installing the engine again to get all the firewall holes done before applying the foam and felt. I tried drilling through felt on the back of my second hand office chair once. I don't think I will try that again. Turtle's panel doesn't seem to have much room left on it. Mine is strictly VFR but I would like to install an electric compass and a 295 or a 296 but that rapidly escalates the cost. Turtle is starting to rub it in a bit! Regards Ross

I am dreading the wings on my J160 as so far all the draw strings in the fuse have been useless as they have been epoxied to the structure. I got around that problem by using a piece of wire and a narrow diameter fairly flexible piece of pvc conduit which I removed after threading the new draw wire through it. I also note that the wing draw strings with their paddle pop sticks attached are hard up against the inboard end of the wing with no free stringat all making it more difficult to attempt a clearance of the string. One party told me that their draw strings were also uselessso they cut an extra hole in the wing to get access to pass the aileron cable around the bend to get to the outboard aileron anchor point. Regards

When I do my flying in the Jab 55-3917 at Griffith I sit my old hand held Magellan GPS 320 on the passenger seat and it works fine. It wasn't much good on a trip to Wagga though in one of the back seats of a GA singlewith no sign of any composite material in its structure. Regards Ross

Hi Louise Jabiru at Bundaburg, Qldsupply Odyssey batteries with the Jabiru kits. The one supplied with the Jabiru J160 is the Odyssey PC 625 see the user sheets below that come with it. Presumably they supply single batteries to anyone. Regards

This model predates the one above by a few years.It has some advantages over the one above but has some disadvantages as well. The seating arrangements are more comfortable but the circuitswere considerably slower and far more stressful as the two stroke motor was chronically unreliable, probably suffering from a lack of maintenance.The unqualified mechanic usually limited his job to cleaning the spark plug with a piece of thin wire,a small tin of super petrol and a piece of sandpaper. It had the decided advantage of being able to do a restart or I should say a restart attempt while in the circuit but due to the nature of the protective footware tended to produce callouses on the bottom of the right foot. The firewall was not very effective and the fuel endurance was completely inadequate as it needed to land probablythree or four times before completing a round trip. Ross on Atco rideon circa 1950. Note the standard features - large dameter UC wheels for more comfortable ride and reduced rolling friction, standard four legged seat with backrest, optional full seat belt harness, standard headset,federation modelprotective footware, air type firewall,transparent guards over dangerous parts, remote controls that works without the need for electronics, pilot activated starter (engine needs to be not spinning if using the starter like the Jabiru motor), ready access for maintenance, simpledesigned aircleaner that does not require dust removal but keeps the gum leaves out of the engine. Ross

Does the temp probe in the Rotax record the head temp or the temp of the coolant in contact with the head? For the radiator heat transfer rate is proportional to amongst other things the difference in temperature between the coolant in contact withthe radiatorandthe temperature of the air in contact with the radiator. A point was made earlier that Rotax cannot use leaded fuels because the combustion chamber does not get hot enough to oxidze the lead residue and thus get rid of it. Pressurizing the radiator by having higher pressure caps effectively raises the boiling point of whatever is being used for the coolant. This means it is still a liquid and not a gas (steam) which has a lower capacity to absorb heat.It takes 540 Calories of heatper gram of water to turn itinto steam if it is already at the boiling point temperature whatever that may be for the current pressure condition. It takes one calorie of heat to raise the temperature of one gram of water one degree C. So pressurising the radiator allows the radiator to run hotter allowing a better heat transfer from the radiator to the surrounding air. According to my old Physics book you would need a radiator pressurised to 33.6 psi absolute to withstand a water temperature of 125 degrees C without boiling. That is about what a normal car 14 psiradiator cap does (assuming pure water)because it is already pressurised by the atmosphere to about 14.7 psi plus the pressure cap for an extra 14 psi. At 150 degrees C the pressure required is slightly more than double that example. Other coolants would have different saturated vapour pressures (boiling points). Pure water boils at approximately sea level at 100 degrees C and at lower and lower temps at higher altitudes (lower pressures). If you went high enough you could boil a non pressurised radiator (without a cap) dry without starting the motor and getting the water hot. The CSIRO at Hyatt in Melbourne did some research on using ceramics in piston engines some years ago. Ceramics are hard, have a low coefficient of heat transfer and a very high melting point. The idea was to protect the engine structure by stopping or reducing the heat getting to the metal. This has two advantages. It allows more efficient combustion in the combustion chamber because it is hotter and secondly it raises the engineefficiency dramatically by virtually eliminating the loss of energy that occurs by needing to havea large cooling system to remove a large percentage of energy from the engine basically to stop the engine seizing up or melting. Regards Ross

Hi Darren Can you see the Warrumbungles from Dubbo at about 1500 AGL. I think I used to see them from Narromine at about that height many years ago. Enjoy your trip

Better legs?

Hi All I have a tail mounted strobe on my J160 not flying yet and it was interfering with the radio until I shifted the shielded strobe wire to run along the side of the fuselage cone instead of parallel and near the shielded aerial wire which runs up the bottom middle of the fuselage. The two wires do cross in the aft end of the fuselage. I think the strobe power box is made of Aluminium so it may also be a source of interference. The J160 has a dipole aerial. Hence itdoes not require a ground plane. The space between the two pieces of the aerial is critical so I made up a spacer that I placed there until the epoxy holding the aerial in place set. Fibreglass gliders usually have their dipole aerials buried inside the vertical stabiliser but may also have a RFC (radio frequency choke) connecting the two halves in the tail. This allows the aerial to be tested for continuity at the cockpit end with an ohmeter - not a 12 volt battery. (radio shouldbe disconnected from aerial while testing with ohmeter) You do not need the RFC for the aerial to work. The RFCpasses electric current but not radio signals, hence its name. It is only in the circuit so that an ohmeter can be used to test the continuity and resistance of the aerial circuit from cockpit to aerial and back. Over time the resistance should be constant. If it changed the aerial wire is broken or there is a short circuit in the wiring. The J160 kit does not include a RFC for its dipole aerial so cannot be tested for continuity from the cockpit end easily. To do soyou need run an extra temporary wire outside while you are doing the test to connect the other end of each half of the aerial as you test it. The initial test w/o the external connection should show open circuit between inner and outer aerial wires if no RFC is fitted. If you want to fit a RFC find a radioexpert - I am not one. Ground all wires to remove any static charges before reconnecting the aerial to the radio. I am a bit worried about my undercoat paint as it appears to be mildly magnetic (and conductive???) as it picks up on amagnet from the floor after rubbing back but that could be from the abrasive paper used. Might it therefore interfere with radio reception and transmission. Paint is High Fill Imron brand. Any Comments please. Regards Ross

It might make the pilot want to be somewhere else.or That could affect his/her navigation! Regards

Hi Jack Maybe just check out Cessna spare parts might be the go. I have a vague idea it has been done before. REgards

Hi Geoff Looks very good. Regards

Hi Jack I did a search for Spring Steel on google that turned up Blue Scope Steel (ex BHP at Port Kembla etc) then their search facility for suppliers turned up theiragent in Canberraas below. I would suggest you contact the agent there and ask for engineering advice on the steel and treatment you want for it. You would probably have to find another steel fabricator or workshop in Canberra or nearby who could treat it for you. I would have suggested Henderson Springs in the past but discovered it is a British Firm and might be harder to get untreated steel from. I think that they used to supply most of the leaf springs in Australia many years ago. I just found another site that claim they will build springs to order. See below. http://www.industrialsprings.com.au/aurora.htm <TABLE =table1> <T> <TR> <TD>OneSteel Metaland - Hume John Place HUME ACT 2620</TD> <TD>Tel:02 6260 1249 Fax:02 6260 1317 </TD> <TD>Supplier</TD></TR></T></TABLE> I hope that is some help- not supplied with current experience. Regards

Hi Crew My wife is always telling me to chuck things out of my office- I don't know why! Well here is a scan of a 1971 receipt that might illustrate some of the changes that have occurred in GA since then. I had to overwrite it because the original was done in very pale blue biro that dissapeared once scanned. Regards Ross

Hi All I saw an interesting posterad for a new model David Clarke set of headphones & mike thathad ANR and sockets built in for mobile phone use and MP3 devices. I think it was due in Australia around Nov or Dec 2006. I don't have any more details than that except the poster wason the front glass door of Adams Aviation Supply Co Pty Ltd at Bankstown Airport. Fernando Villalon is the General Manager, Flight Instrutor & Charter Pilotthere and his email address is [email protected] web site: www.adamaviation.com(scans of their catalogue) They also have a CD available Tel +61 (0)2 9790 7199 Fax +61 (0)2 9790 3189 Mob: 0404 379 150 [email protected] Ross

Hi Smokey I did not say that Jabiru approve Ethanol in their fuel. In fact the "Jaba Chat" article on Page 11 dated December 2005 on the Jabiru Web site mentionedin my previous postneeds to be read carefully. The only mention of alcohols (and ethanol is one of them) was in connection to the damage they would do to the sealant used in their fuel tanks - there was no mention of engine components - presumably if it could not go in the tank it could neverget to the engine. The Jaba Chat article above then wasnot mainly about Ethanol but about the antidetonation qualities of Avgas versus non quality controlled auto fuel. For Jabiru use I suggest a personal phone call to Rod Stiff the owner at Jabiru in Bundaberg to clarify his position on fuel use in Jabiru Engines. Regards Ross

Hi Smokey That possibility had occurred to me but I have not invesitigated it. I thought it inevitable that ethanol would be in all auto fuel eventually which would be potentially dangerous for aircraft because of the potential water problems. There was an article on the subject in one of the aero mags but I did not record the location. It mainly showed a method for deciding if there was ethanol in the fuel or not amongst other detail that I cannot recall. Just do a google search to find more detail on the sloshing agent and possibly look up the Jabiru net site http://www.jabiru.net.au/ See P.11 of the Dec 2005 "Jaba Chat" on the Jabiru web site aboveunder news for Jabiru's perspective on fuel used in their engines. Regards Ross

Hi All From my research I have discovered that there are two different sloshing agents that can be used in epoxy fuel tanks one of which is compatible with ethanol blended fuel. The other is NOT. Jabiru has an advisory on Ethanol to say that at least in the J160 serial number 14 that I own the sloshing agent used in the wet wings is incompatible with ethanol blended fuel. I am not aware if theyhave changed sloshing agents since then. You can have a choice of fuels for the Jab engine (with conditions - see the Jabiru web site); because of the sloshing agent the choice is removed if it involves a fuel with analcohol blend(Ethanol is an alcohol). Regards Ross

Hi Stuart It might help to mention which model Jabiru you are about to fly. Regards