Hi! All industrious engineers ...!
I would suggest you make an approach to Pat Tunney. He took the BMW Project
under his wing no doubt spent mega bucks in cash and time but I think he
abandoned it as a nightmare. He subscribes to this forum.
For what I know you have a hitherto unsolvable problem since the power
stroke resonance develops a harmonic torsion resonance shock wave to run up
the propeller blades and viewed from a position at the end of the rotating
propeller arc you can see the propeller blade take a shape rather like a
letter "S". (very dangerous place to stand) Europa had an engine c/w
propeller mounted on a car trailer and ran the assembly at a "workshop"
event at Elvington Airfield with minions of customers and potential
customers littered all around waiting for the possibility of certain death!
To my knowledge such a hormonics pulse eliminator needs yet to be invented.
...
..........Perhaps try a "vee" belt final drive to the prop ? .or even
contra-rotating props !!!!!!!!
The Rotax slipper clutch employs a rotary spring loaded cam drive which is
a copy of crank shaft drive situated prior to the primary drive chain on my
single cylinder 1936 Velocette 350 KSS (overhead cam) which maybe goes part
way to effect a solution. Those chaps had wonderful opportunities to
exercise their engineering abilities for the year.
Incidentally ( not to expand on my previous Jabiru experiences) I had a
serious torsion resonance peak induced in the propeller/crankshaft
combination of my Constant Speed MT Propeller which was acceptable since it
could be accelerated though but MT Propeller Engineers placed some
restriction on the operation of the combination. Even, though being a six
cylinder, the torsion graph plotted was scary and clearly defined. With
random propeller mounting extensions the torsion effect can be caused to
develop back along the crankshaft to be between the main bearing journals
and so fail the crank shaft. ( I've seen photographs)
Regards
Bob Harrison. G-PTAG
_____
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of G-IANI
Sent: 23 September 2010 10:35
Subject: RE: Europa-List: Next steps -
Cleve
My understanding is that the Europa work on the R1100 was stopped as they
could not eliminate a torsion vibration problem with the setup. I speculate
that an R1200 installation would have the same problems.
In May 1997 it was being worked on. This was the period when a man called
Adam Kingdom became CEO. Things do not appear to have gone well and he left
in mid/late 1998. News letters in this period are very sketchy.
Other almost certainly know more than I do
Ian Rickard G-IANI XS Trigear, 300hours
Europa Club Mods Specialist
e-mail g-iani@ntlworld.com
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