Jabiru powered Gyro

[MechFx]

Whatever happened to this ?

[maulonir]

I believe it is still sitting in Don McMillans garage in Cairns. I think he had problems keeping it cool.Rob

[birdy]

Yeh, probably cooked it.I quized Jabiru bout putn one on the wasa before i found the 914, and they said itd never keep cool enuf.

[Brian]

and they havent got enough torque to push a gyro. A Jab motor was fitted to a gyro at Broken Hill but as well as cooling problems, it wouldnt pull the skin off a custard.....

[MilesW]

and they havent got enough torque to push a gyro. A Jab motor was fitted to a gyro at Broken Hill but as well as cooling problems, it wouldnt pull the skin off a custard.....Brian, you might want to check the specs. Torque is definitely not it"s weak point. Might have been some other factors at play.For practical purposes the Jab 3300 can be compared to the 912s and 914, and the Jab 2200 to the 912. It is really easy to understand why folks want to drop one of these into a gyro. They are a tantalizing poposition. On paper they are just about perfect. Unfortunately, real world experience has not been good. Some really clever ducting to address the cooling issue and a low ratio PSRU to fully utilize the numbers might help them find an application. Miles

[Brian]

A PSRU would help. There are some 15 odd Jabs in the Mildura area, actually, it could be more now, but a lot of them have had reliability issues and thats in aircraft so I"m not sure how they would stand up to pushing a gyro.On paper they are just about perfect. Unfortunately, real world experience has not been good.That probably sums it all up. Hopefully, they will get the goods together someday.

[tonydenton]

the jab engine factory[ a seperate privetly owned company ] is atop place and full of top people. a head spin to go for a tour

[tonydenton]

the jab engine factory[ a seperate privetly owned company ] is atop place and full of top people. a head spin to go for a tour

[birdy]

Scuse me scg ignorance, but wots PSRU ?

[asra]

Scuse me scg ignorance, but wots PSRU ?Propeller Speed Reduction Unit/Drive (Gearbox)

[tonydenton]

obviously didn"t mean to press it twice . dunno how i managed that one.

[Brian]

Thanks for giving us the information Tony. Shame to see another Aussie manufacturer left for dead ...again!Makes you wonder what the Chinese bits are going to be like. I know they can make stuff to a very high standard but they are also very cunning and will make things to tick the boxes and what you get aint what you think it is.

[asra]

Makes you wonder what the Chinese bits are going to be like. I know they can make stuff to a very high standard but they are also very cunning and will make things to tick the boxes and what you get aint what you think it is.It comes to manufacturing costs, the west is becoming too expensive and many companies are discovering that China is not only cheaper but they improve the products by way of reverse engineering. There is an interesting tread on RWF ( http://www.rotaryforum.com/forum/showthread.php?t=27304 ) about a West Australian company making PSRU in China, not only they reversed the engineering, legalities aside, apparently they are delivering unlike the original box with only a flex plate, this one has a innovating designed flywheel, very interesting and this is what he had to say: The area in improving the AeroFlight 33 was to have a serious look at the configuration you mention above, using a flywheel with a low mass moment of inertia will undoubtedly create what is called torsional vibrations. We have eliminated this by delivering this particular box with a proprietary engine coupling system, which typically consists of an engine specific weight pressure oil filled flywheel, the starter gear, and in between the flywheel and box we have a Centaflex rubber coupling connected to a splined hub, and splined shafts connecting to the gearbox. The improved coupling system removes over 99% of all engine torsional pulses which the engine produces at takeoff and cruise power, and provides the propeller with an operating environment which is essentially devoid of engine torsional excitation.