damkia
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Everything posted by damkia
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OT, but I love this "taught me" tag line from BP2469 above.. "Skydiving- time management"
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Petition to block the sale of Wondai airfield to developers
damkia replied to cscotthendry's topic in Governing Bodies
Isn't there something about "continuing use" in relation to the sale of these properties - ie it was an airfield long before there were residences around. I'm sure this or a similar scenario was covered in another thread... -
"15. When a man sits with a pretty girl for an hour, it seems like a minute. But let him sit on a toilet for a minute, & its longer than an hour. Anonymous." Fixed...
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"Would the last person to leave the Boardroom please switch off the light..."
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Western Australia Ultralight Fatality
damkia replied to ave8rr's topic in Aircraft Incidents and Accidents
Who would that be, and what are the qualifications? We have had a few changes in the senior management, and I think this deserves more that a one word reply... A tech officer (or whoever else) does not automatically have the expertise required for investigation of incidents by virtue of their inherent tech knowledge. -
Western Australia Ultralight Fatality
damkia replied to ave8rr's topic in Aircraft Incidents and Accidents
Firstly, condolences to the family and friends of the gentleman involved. My question is do RA-Aus actually have anyone that is capable of doing a "proper" investigation of incidents, ie has formal recognised training in incident investigation that would be consistent with a coronial inquiry as an "Expert witness"? -
In the absence of any qualified individuals within the organisation to accept the roles, it would seem that external appointments should be considered for Board positions, appointed by an interim independent HR management team ("Talent acquisition" phase) until such time as all positions are covered by people with known and demonstrated competencies in their area of expertise within the Board. It is clearly not good enough to let someone "have a go at it" by virtue of being the only person nominated at an election. The side benefit of this fresh blood would be to short circuit the lack of competence, infighting, and bloc building that has plagued the RA-Aus in recent times.
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Oscar (#20) makes a very valid point about ignoring geographic location. This I would have thought originated from the amalgamation of old clubs into the new RA-Aus and is more of a historical quirk than any real benefit. One would have to think that a council faced with a national body on its case could be swayed more than having a "bunch of disgruntled flyers" popping up at a council meeting. Seven is a good number as it will guarantee a result on every vote, and still give less opportunity for blocs. Suggested roles: CEO Secretary Treasurer Registrations Training Tech Officer Compliance monitoring (CASA liaison) A suggestion for two observers from general rank and file to be present during board meetings (no discussions with board members during meeting) "Keep the bastards honest"
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"A bed above ground is preferable to a bed below ground..."
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Try to actively avoid ethanol in fuel as it is hygroscopic (affinity to attach to water) and it can lead to collections of water in your fuel tanks, carburetor and jets, leading to engine failure. Ethanol is capable of carrying water past fuel filters. This water is mixed (dissolved) by the alcohol and is not evident on the usual fuel drain preflight check, much the same way as you mix scotch and water without the water separating. This deposition of water is more evident at altitude where the fuel vaporises at a lower temperature as it leaves the jets of the carburetor leaving the water behind. Some forms of rubber hose are also degraded by ethanol. Given these hoses usually are after the fuel filter, rubber debris can also get into the carburetor causing an engine failure. Plan NOT to use ethanol fuel, even if it means going up a grade to achieve it.
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...or the more "neutral" version: A leader either takes everyone along with them as they forge a chosen direction, or they go it alone and risk drowning in the morass with no help at hand.
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Quite honestly the one thing that keeps popping in to my head as far as the RAA from CASA's point of view is "Cut your losses".
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We know the costs of CASA (by way of simple GA, or Experimental administration through SAAA), we know the resultant effectiveness of CASA We know the costs of RAA (by way of the myriad of licening types and confusion), we know the resultant effectiveness of RAA We have the data.
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Agree totally. It is all about numbers too. How many people actually are registered with those two operations? I would suggest no where near as many as there are in the RAA.
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To incorporate the aircraft back into the CASA fold per Dafydd's posts would be the most cost effective and appropriate way of controlling and maintaining governance issues. Currently we have duplicate governance from CASA and RAA, one of which has been shown to be not up to the task by a long shot. "If you want a job done correctly, do it yourself"
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http://en.wikipedia.org/wiki/Commer_TS3 No diesel is smooth or quiet...
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This I think will be one of the biggest challenges, isolating the prop torsional vibrations (differing air densities through the arc of the prop swing due to AoA of the aircraft) of from affecting the cam timing.
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Measured from where? As I stated earlier it should be smoother anyway due to the opposed pistons in a single cyl due to the almost perfect balance of internal forces (some very minor cyclical harmonic mass issues from the conrods aside). The comparison to a standard triple is probably not valid in relation to smoothness.
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That would be at the pistons crankshaft, NOT the output off the camshaft... I understand what you mean, but you haven't taken your thinking through to the power output end. I agree 1 pulse per 240 degrees of the piston crankshaft, divided by two due to the camshaft "output" gearing equals 1 pulse per 120 deg of output off that camshaft, and that is the same as a normal 6 cyl engine. Think of it as a three cyl (as you have correctly) with integral 2:1 gearbox to the only output available.
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Remember that the "drive" is from the camshaft, at a 2:1 ratio, every pair of pistons makes it up and down the cyl twice per CAMSHAFT (output) revolution. This makes it exactly the same as a standard 6 or 8 cylinder four stroke. Having opposed pistons in close proximity in the same cyl should make it smoother. Compare that with slightly offset pistons in their own cyls all pushing their own little bit of a crankshaft. Porting will only be an issue depending on total displacement of the individual cylinder. From what has already been written, (IIRC) then it is a 3 "cyl" 2.4l engine = 800cc/"cyl". If the heads can flow the required volumes at 6000 rpm of the pistons (ie 4800 l/min at 300 rpm OUTPUT speed) there should not be an issue.
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Many thanks...
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Certainly not trying to insult or offend but my rationale was the style of valving used is a poppet, and that the inlet and outlet are equidistant from the central combustion area, as distinct from the "inlet over exhaust" where the valves are essentially "stacked" on top of each other at different heights from the combustion chamber with the inlet in the head and the exhaust in the block operated "opposed" to actuate opening. Both valves in Bex's engine exist in an OHC head and are actuated in the same plane for opening (although angled to one another).
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Poppet valve. Pocket valve is another thing altogether https://en.wikipedia.org/wiki/IOE_engine
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What is needed is publication of the full CASA audits, not simply a few of their eventual recommendations. Members of the RAA should have full access to all of these issues though the Minutes of Meetings transcripts, whether they be full AGM's or all Board meetings ( http://www.companydirectors.com.au/Director-Resource-Centre/Organisation-Type/Organisation-definitions per Daffyd's link and what should have been in the Constitution of RAA).
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I would have thought you could get away with a simple porting solution (exhaust+/- inlet), rather than go to the trouble of using an OHC head with it's now very awkward shaped combustion chamber... I think you will find that having a center of force from ignition at a significant distance off the line of the pistons themselves is going to cause a few issues, mainly the flame front propagation from ignition causing piston slap (unequal displacement of the upper and lower edges of the piston) leading to galling of the pistons/cyls. The actual bottom of the piston is going to be quite a distance away from the initial ignition and will probably not feel as much of the force of the flame front (cooled by distance and time). One other issue will be a significantly hotter side of the piston/cylinder with all the thermal stress of the OHC head and exhaust concentrated to one side (the old "flat head" problem of cooling the exhaust area). My 2 cents worth for discussion....
