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damkia

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Everything posted by damkia

  1. May not be the best nickname to use either for other reasons. People may take it the wrong way... Can you spell "Kerobokan" ?
  2. There are a few of us interested in this engine. Would it be possible to start another thread about it?
  3. I think it comes down to the "Bathtub Curve" of reliability ( http://en.wikipedia.org/wiki/Bathtub_curve ). They do seem to have a vertically raised "Early Failure" curve, and some of the failure modes have been noted to be terminal (in flight complete loss of engine power). Having said that, there are some that manage to get past this part of the curve and will last into the 1000-1500 hrs before needing a full overhaul. The Jabiru stated TBO of 2000hrs is optimistic - based on estimated general longevity figures (from RA-Aus magazine) they should go into "on condition" at about 600-1000hrs. The fact that Jabiru do not make their failure rate/mode known (nor is it readily available from RA-Aus in tabular form - nor for any other make of engine either...) does not increase confidence in their product in my book. The only way is to go back through the RA-Aus magazine and try to get a feel for how many, and how they failed.
  4. It has been posted before with much discussion. Can't find a link for it
  5. The standard decent rate that was quoted by one of the QANTAS reps was given as 3000'/min. The aircraft had decompressive incident. The decent was from FL 40 to about 10 000 AGL in about 8 mins. Some of the early reports... http://www.couriermail.com.au/news/queensland/qantas-tight-lipped-on-why-737-plane-diverted-to-rockhampton-just-before-due-to-land-in-townsville/story-e6freoof-1226564425248 http://www.recreationalflying.com/threads/qantas-plane-makes-unscheduled-landing.56249/ At the stated decent rate of 3000', yes, when you factor in the horizontal velocity and the "nose down" attitude of the aircraft supporting your seat. Next time you are in a plane try going to the loo and doing a bit of a jump on the way there while the A/C is at TOD just starting to descend. You can "lift off" for just a bit longer than you do on earth, not quite weightless, but "light"....
  6. 84 - 88kg (+ exhaust???, wet??? - not noted...) is more than a Rotax and Jabiru for the equivalent HP and both those have the safety of twin spark plugs per cyl...
  7. Most motorbike motors are only used at the very low end of the hp range (circa 5-10%? on acceleration) for very short periods of time before effectively "idling" in terms of potential power output. Simple maths of power requirements to keep a 100kg rider on a 250 kg bike at 100 km/h including a drag factor of say 0.4 would give you a rough idea. This is clearly evidenced by the 250-350 km/h most modern bikes are capable versus the pottering around at 100km (or as in your assumption, 70 km/h average). Quite literally it is a very lightly loaded scenario. Note that a 1.5t car takes about 15kw to keep it going at approx 100km/h, and a bike has a hell of a lot less weight and frontal area to push through the air. Compare that with an aircraft engine that is rarely used below 80% of full power... If you subjected the M/C engine to the same test standard as an aircraft engine I think you would see the reliability and effective "TBO" reduced significantly.
  8. Good to hear the "Preparation H" (hurry-up) is beginning to have an effect.
  9. 42 hours later.... Only minor damage, one broken tile leaking water onto the ceiling plaster, otherwise unscathed (if somewhat smelly)
  10. Checking out whether the weather is worth weathering or not......... I am SO glad I ripped up my lawn and planted rice. My inbuilt weather forecaster is when ever I top up my pool you can GUARANTEE that there will be a deluge a couple of days later. I have now taken out MORE water from my pool that I topped up last Tuesday:bad_mood:
  11. Not necessarily. It may well be the upper limit of what the engine could take due to the heavier reciprocating masses involved, when combined with the limits of metallurgy/technology of the rest of the structure of the engine. You could probably get more out of the engine but you would need to add weight in the fixed parts of the engine to strengthen it. A more realistic measure would be how many thousand hours per hp per kg engine weight (apologies for the mix of measurements) A very good example of what I am referring to would be drag car engines. Light weight, powerful (high hp/litre), BUT need an overhaul after about 10 minutes at full throttle (20 runs), and only last less than 2 hrs before being disposed of (if they haven't spectacularly scattered their parts to the earth by then). Motorbike engines tend to be towards this end of the reliability scale, rather than the ability to go for thousands of hours like aircraft engines (and diesels). Something has to give in the big equations....
  12. I would imagine nothing would be more threatening to the RA-Aus Executive at the moment than peeved off "shareholders" plotting a coup and beying for blood. Makes you wonder how many of them are sitting in their office with this forum in the background...
  13. More likely Stardate 2250's or so... http://en.memory-alpha.org/wiki/Stardate
  14. Now, what is that "1 in 60 rule" to the fourth dimension???? -------- This could be a competition for the best caption.....
  15. Perhaps add a dislike for "textspeak" rather than spelling. I'm sure those that have been to school in the last 30 years have learned to type full words on a full keyboard. Those of us past that would be fully aware of good communication skills with regard to the written word and grammar. We do not have any real need for the "140 character style" shorthand that some may use. Would it be possible for the soft hide to be based on the ratio of likes to dislikes? (ie a 4 or 5:1 ratio)
  16. Ian, Is there any thought to restricting people from picking an old thread, > say 3 months old, and simply add a non vital/trivial post to it for no reason? (commonly known as "grave digging" in other fora) I have noticed it a couple of times lately... I'm not complaining about people that value-add to the thread as a source of new information, simply suggesting that some sort of a statement be made about the practice of grave digging.
  17. Same sort of mathematical trickery involved too. We know the answer, we're trying to work out the question.........
  18. Ditching is generally considered to be a forced but controlled landing into a non aerodrome environment ("PanPan" emergency). An example cause would be visible leaking fuel from a wing tank (certainly not the only reason, though). If fuel ignited it would be a Mayday emergency, putting down as soon as possible wherever possible. You can ditch into a paddock, water or other area.
  19. I thought that someone may have "taken offence" and had the site taken down. When it disappeared off the DNS servers I was convinced. Thankfully, "IT LIVES!!!!!"" (apologies to Mary Shelley)
  20. Let's not forget reimbursing any and all costs of any actions of the RA-Aus which have been signed of as him as "President" since his resignation. My gut feeling is that anything signed off since the resignation will be null and void, possibly including any of the administrative work behind the registration issues of late, and their subsequent renewals.
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