deadstick

That's a throw away mate.

 

 

Hi Roger, I will be at hangar 7 this afternoon about 1500. Moving a few planes around. Drop out if you have the time.

 

 

Bladder tanks are safer too! They tend to bend and deform rather than rupture like ally ones, the self sealing ones are a laminate construction, a layer of rubber then a layer of sealant in gel( goes hard and reacts with dual contact) then another layer of rubber.

 

 

Good to see another member here that is not too far away from us at YQDI, welcome Roger.Ps Deadstick we having our monthly bbqs on the second Saturday of the month, you will have to get down to us soon:yes:

LOL I'm really dragging the chain on this one aren't I? Can't wait to actually get there and meet some like minded peeps.

 

 

Hi Roger, good to see another member in Tamworth. I have two Jabiru's at Tamworth airport drop me a line would be great to check out your plane.

 

Chad.

 

 

Another one:- an instructor I once had used to fly the boo in Vietnam, he had an engine out and had to land in a rice field, as they were skidding through the field they noticed a local standing directly in the path of the plane, unable to to anything they just held on waiting for it to stop. The local passed directly through the still running propeller without a scratch. Later on they figured out that there would have been a prop blade less than a foot either side of the local.

 

 

A mate of mine who was a flight eng on the SQN tells a story of the sqn's Officer commanding and commanding officer out in a requal flight just after Christmas leave where they were conducting low level navigation when they banked hard over the top of a ridge and felt a hard thump, on return to base it was discovered that they had major damage to the left wing and the subsequent investigation revealed that they had sheered a foot round tree off mid way ( top of the ridge) with the left wing.

 

 

So, is there any info on the cause of the failure yet?

 

 

What are the co-ordinates for the crash site?

 

 

A few years ago, My j160 snapped two through bolts( upper and lower fwd number 2 cyl) while a friend was flying it, did not keep running, he said it spluttered at 200rpm for a bit then quit. All at 200 feet on takeoff!!!

 

 

If leak downs, plugs, rotor caps and leads have not been checked then that's the first port of call! The rotors on these like to come unstuck and wobble on the shaft, also they tend to corrode fast. If the basics have been done and it is passing the checks then you could indeed have a dodgy lifter, you can check lift at the rocker arm itself I cant remember the figure. All it takes is a minute bit of crap stuck in the plunger valve and the lifters go soft and don't provide full lift, effecting cam duration as well.

 

 

You are being taken for a fool, as a LAME and Jabiru owner ( 2 of! one with 4cyl and one with 6cyl) if I saw numbers like that the engine would be pulled immediately. That engine needs work before it can be classified as airworthy. The LAME in question is referring to continentals which have a very broad definition on leak down tests. Jabiru's don't! If you are keen include the cost of a rebuild in the purchase price and make it a condition of sale. Experience with these engines had led me to start searching for an issue when the leakdown a hit 70/80.

 

 

I have had one engine, a 3300 where the mains gaps closed up after the first through bolt ad was carried out. The post mortem on the engine revealed unusual wear in that the crank had worn and not the bearing, the mains gaps were measured and a few were at 4thou the minimum clearance at the time. Independent examination and report indicated that the increased clamp of the 12 point nut and new through bolts had closed the gap slightly. Having read the new SB I See that Jab have developed a check for the turning friction of the crank now? looks like a hip shot to me! so many factors can effect this measurement!!!

 

 

So, if the engine has been built already and the mains gap is set won't more torque on the through bolts close the gap on the main bearings and cam tunnel?

 

 

Current 3300's are almost 130hp. The 914 is 115 for 5 minutes. They are not the same "power."

Hi, where are you getting these figures from?

 

 

Hi deadstick would be interested to know your experience's with thru bolt issues , in particular , which side and whether top or bottom on each side ie oil filter side or dipstick sideA.D.

Only ever snapped one on the j160, it was number 2 cyl upper fwd and upper rear bolts that snapped. Of note this engine had the shims under the base of the barrels with goop on both sides, not a great setup.

 

 

And I'm sure we are both very happy that you're not! However you response to a polite and genuine question was neither friendly or helpful. Mate, I am disappointed that you are either unwilling or unable to help out a fellow aviator, or did I unwittingly touch a nerve?

Perhaps I misread the tone of your request, in which case I do apologise bit tired tonight and up to my ears in bullshit faults on a dash 8 Q400. To read the statement you will have to go back to the beginning and read the one of the early press release's can't remember which one and am on night shift ATM so don't have time to look for ya. Along the lines of jabiru have identified three common modes of failure-thru bolts, flywheels and valve train.

 

 

So let me get this straight, Jabiru themselves have admitted to CASA that there are still three modes of engine failure that they can't explain. Yet we are outraged because CASA have proposed to act under their charter to minimise potential risk to other human beings and the unsuspecting public! If I recall correctly a 19 registered aircraft is not allowed to fly over a populous area unless it is fitted with a "recognised and authorised" power plant and given a written waiver by the tech manager! It seems that this is exactly the restriction that is being proposed should Jabiru be unable to rectify the issue. I personally own two Jabs and have a well documented history of trouble with them both and stand to lose a lot of money should they devalue any further ( already at rock bottom) but I understand that the regulator has a job to do and expect them to if there is in fact an identified issue. From the outset Jabiru have donee everything they can to lobby, fearmonger and ignore the regulator, I mean they are asking people to request that the minister order the safety regulator to ignore their concerns for Christ sake! Even after recognising publicly that there is some work to do they are again trying to bias the data by ignoring negative information in their survey, of which should have been done a decade ago. I am confident that they can resolve these issues but not under the current approach.

 

 

Why cant the regulator do their job? what is there to hide? if there aren't any problems with the power plant in question then nothing will happen! if there is then it will be identified once and for all and fixed! win win.

 

 

Righto...I'll drop an email to Darren Barnfield and see if I can get to the bottom of it thenAndy

Andy

 

It's all to do with the type certificate, The Jabiru UL-D and J160-C are Type Certified by the Civil Aviation Safety Authority (CASA).

 

The J120-C, J160-D, J170-D and J230-D are designed and built to ASTM Airworthiness standards.

 

Difference:-

 

A J160-c has a type cert whereas the latter D models have a special type cert. Both fit in as LSA' s but the engineering authority is different (CASA vs Jabiru) and both can be registered 24 if factory built.

 

 

Could be a problem here.I get 3000- 3050 at takeoff with full fuel.

Phil

Which propellor are you running Phil? I too get 3050 static but with the sensenich not the standard jab paddle.

 

 

Ianboag, hi mate there's a couple of causes of through bolt failure. First is quality control:- I received a batch of the new 7/16 through bolts to find a clear stress raiser on the machined neck of one, another had the thread formed strangely. Second:- the nut riding on the radius of the base flange for the barrel and placing a side load on the bolt. Third poor assembly at the factory causing chaffing of the case halves and them hammering on the bolt, I have seen locating dowels fall out of case halves when split on low time engines. Fourth I suspect there is a resonant frequency being generated, some times you can here it:- flywheel bolts fail not from shear ( flywheel still located on dowels) but just snap at the base I suspect due some form of pendulum effect hammering through the crank.

 

 

For those interested and comparing the 914 Rotax to the 3300 jabiru, the rotax's is going to eat the jabiru at just about all power output points. Example, j230 medium or low density altitude at takeoff power, the HP curve at 2800 rpm ( which is what you will see in a 3300) is below 100hp same aircraft and DA but with the turbo Rotax, the turbo compensates for most DA performance loss and performs better right through the altitude ranges. Add in an adjustable pitch prop and you have your self 115 hp from takeoff to let's day 10k feet. Adjustable pitch prop on a 3300 and you may see 120 on takeoff but not for long as you climb. The hp figures for the 3300 are at ISA conditions and spinning at 3300rpm so who ever see's 3300 rpm on takeoff?

 

 

Seems to me that CASA was made privy to the draft ATSB paper being put together on recreational engines reliability.

 

 

The Jab is white for a reason. Ever hear the term "glass transition temperature" for an epoxy resin laminate? I suggest you look it up, before you add much in the way of a colour scheme. The Jab is made using LC3600 resin. The structural testing was conducted at or slightly above 54 C, because that's the temperature considered necessary for a white-painted surface in full sunlight on a nominal 37 degree C day at sea level.AMC VLA 613 ©

 

Material Strength Properties and Design Values (Acceptable Means of Compliance)

 

Test Temperature –

 

a. For white painted surface and vertical sunlight: 54°C. If the test cannot be performed at this

 

temperature an additional factor of 1·25 should be used.

 

b. For other coloured surfaces the curve below may be used to determine the test temperature.

 

Curve based on: NASA Conference Publication 2036

 

NASA Contractor Report 3290

Fully aware of this thanks dafydd, you can see the weave coming to the top on some jabs that have been painted, by paint scheme I assumed it would be understood as the stick on graphic schemes. Interestingly the Jabirus being sold in America and South Africa have near full paint schemes not stick on's. I was thinking of covering the belly, so you think there would be much reflected heat from the ground?