David Isaac

Huh.... funny how the truth changes the whole perspective. What happened to the alleged engine failure???? Explain that one to the insurers, a deliberate aerobatic entry where there was insufficient height to recover. I wonder if he even did his basic HASEL checks.

Apologies Gadalph, seems I have misread your intent. Bloody hard sometimes with damn written stuff ...LOL

Well with my experience with flow testing in high performance V8s, why would you bother with an engine that peaks at 3,000 RPM?

I reckon my J1B would have trouble keeping up with my Fordson Power Major in road gear down the runway at Luskintyre Kaz .... Well at least for 100 metres LOL

Good question Dafydd, I don't know. Col made the statement in post # 109 and that was why I questioned the need. Rod Stiff also mentioned the need to do the hand reaming In his latest Jabbachat article as well, another reason why I was questioning its need. All these 'needs' point me to a fundamental over heat problem. Perhaps it is a systemic problem in engine cooling installation design or operator abuse. But then again if the engine installation does not include accurate CHT read out facilities, is that not a fundamental installation design flaw given the POH has CHT operating limits and the consumer should be able to rightly rely on the CHT instrument accuracy, especially on factory built LSA models. In any case how do we know that the test bed cooling system is the same as the produced one? BTW I am not suggesting there is a difference, but I know what manufacturers have historically done with products requiring Listing verification.

You are on sweetpea. The problem will be me getting off my ass. LOL

Well you certainly missed my point. I am aware of what Col Jones stated in post # 109. My question was simply why is this so necessary on a certificated engine if it is operating at correct temps. The symptoms Col Jones was describing are typically a result of running at over temps. So why is this happening with a certificated engine in a factory Jabiru installation and not happening with the other engine that is so popular in other ultralight aircraft.

Firstly I am absolutely not saying that "the design of the engine and the design of the aircraft should be such that no matter what the operator does, it's impossible to exceed limits, you are demanding more than the certification standards call for." I have no idea how you would deduct that from what I said. I have been flying GA aircraft since I was 16 years old and operated C180s, 182s, 185s, 206s all with cowl flaps and I understand operating engines properly and I have an extensive knowledge of what goes on internally in an engine and the issues surrounding operating temperature. I did say "exceeding certificated temperatures in normal use and application..." and by that I mean operating the aircraft normally as in accordance with the POH. Just to clarify that I do not consider I am ignorant on these issues. If you operate the aircraft in accordance with the POH (normally) there should not be over temp issues unless the PIC is asleep.

Dafydd, I can accept required maintenance if it is clearly documented, but not if it attempts to compensate for poor design. And clearly these valve guide and valve issues point to over temp. If the engine is exceeding certificated temperatures in normal use and application then I would allege the manufacturer is misrepresenting to the consumer that the engine is certificated and Mr Stiff's pontifications on Jabbachat about illegal changes by owners removing the certification of his engines should equally apply to his factory installations where such factory installations cause in normal use, the engine to exceed its certificated approved temperatures.

I take a more experienced approach to statistics Bandit and I agree with you, however, in some of my experience it is the absolute knowledge of how to manipulate statistics to prove a theory or actuality to the point of fraudulent misconduct that I have found, and this is the point that Winston Churchill was making in his famous statement above.

Yes we do Richard, but people don't seem to fiddle with the Rotax or Lycoming series ..... why is that .... possibly because there is NO NEED to do so. Do you hear a Rotax (Bombardier) director suggesting you should check the guides every time the rocker covers are off ... or use a hand reamer FFS. Why are the rocker covers off so regularly, does this fundamental stuff escape everyone's fundamental logical thinking???????

FFS the better question is why is there any need to do this on a certified engine FFS.

Who is that Tubz, the C206 pilot or the station owner ....

I have a great idea Potts, I'll fly my Auster to WA and you can train me in a low level rating. That way you can have an interesting trip down memory lane while you give me a hard time in flying training. LOL.

What the hell does that statement mean Deb or whoever you are ...

A little obvious and engineered don't you think ......

I say ... The best of opportunities to them at Brumby. It's about time there was serious competition to Jabiru, maybe this will put some serious accountability to their pathetic responses to their engine issues. What Potts (Ralph) said, says it all, and if Brumby can stay customer focused (externally focused) they should be able to put some serious completion out there. All the best, even better that it is in a small Australian country town.

What ... 'needling' a guiding principle ... LOL

Welcome to the 'Nut' house Ian. There is plenty of room for Brits on here. Just watch out for that bugga Phil Perry (another Brit with an identity crisis, he still thinks he is a Brit, but really he is an Ozzie, he lived here once and then went home to the mother ship ... LOL). He is our resident comedian. Seriously, we are a real lovely bunch ... we scrap sometimes, but we still love each other in the morning (as they say). LOL

You might get away with that in rather agricultural diesels, but from what I understand, adding 'petrol' of any kind will damage the modern high pressure common rail diesel fuel system.

Ironically I think the Sapphire was also technically an ANO 95.10 aircraft as well was it not? However in comparison to the original 95.10 types it was very fast and slippery. Aircraft like the Scout, B1RD and Frank Bailey's Mustang were single surface wing and very slow. Chances of serious injury from a prang were less than falling off a trail bike. These early single surface machines were 'relatively' safe compared to much faster later machines (e.g Sapphire). I remember in the early 80s trying to stall and spin (yes call me stupid then) Frank Bailey's Mustang, it wouldn't clean stall, it just entered a mush sink rate like a big parachute. The only real stall could be achieved was by pulling it up into a hammer head style stall and all it would do is drop the nose rapidly and start flying again in what felt less than a 50 ' height loss. Every attempt I made to stall and spin failed , ( I was GA aerobatic rated then) it would simply start flying again. I know from conversations with Frank back then (I spent a lot of time with him in those days) it was the original intent of his 95.10 design as they were designed to 'teach yourself to fly'. So we had the original un-spinnable single surface wing 95.10 machines so no spin testing regimes or requirements and then the slippery versions like the Sapphire which was probably quite spinnable (my opinion) .... But 'we' wanted faster and heavier and higher and then two seat trainers, that was when we needed real design and that is where the major compromises began IMHO.

I have never really understood why spin testing requirement was not there, especially given the nature and use of the aircraft. Wasn't the Sapphire one of the first ultralights tested and certified to the then ANO 95.25?

I think it would be easier to recirculate the fuel through the tank wouldn't it Tubz; a separate heater is one less point of failure to worry about. If they used a high pressure common rail design like my Landcruiser (using the fuel as pump lubricant), the returning fuel goes through a cooling unit under the floor, so obviously lots of heat available.

And without an increased 'up' force from the elevator simply banking the aircraft wouldn't necessarily turn it, as we do in a side slip and you have pointed out.

Dafydd, was any spin testing done on the Sapphire?