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Thanks Todd.
Your comments re turbo make sense.
And thanks for your thoughts re in flight failure modes and particularly cooling on that fist flight.
I won’t be flying the test flight, but hope as you mention to be on board monitoring the engine.
Cheers
Steve Izett
> On 18 Mar 2018, at 4:30 am, Todd Bartrim bartrim@gmail.com <flyrotary@lancaironline.net> wrote:
>
> Hi Steve;
> (skip this first paragraph for those not interested in turbos :-)
> The guy you should be asking about turbocharging is Dave Leonard. With a plane like a Glasair, I'm guessing your requirements would be continuous boost for high speed performance which the stock Mazda turbo has proven to be unsuitable.
> Some builders have had some success with aftermarket turbos, but I believe that all of these also required an oil pump to return the oil to the pan, which starts to quickly add to the complexity & weight. The stock Mazda turbo makes for a far better, simpler, compact installation with gravity oil return. But is not reliable for continuous high output duty. However Dave apparently solved this problem by having a stock turbo heavily modified by an aftermarket turbo company that specializes in that. I believe it has performed well for him.
> Dave has gone quiet on the list over the last few years, but I suspect he's lurking quietly in the shadows, so hopefully he will speak up and give you some details, as well as let us know how he's doing? But he did report in much detail as he was going through this process, so the info you need should be found in the archives.
> The reason my install wouldn't help you much is my mission profile is much different. I'm already packing more HP than the RV9 was designed for, but that is more a function of the wings Vne restriction. I use the plan to use the turbo exclusively for take off and climb performance in the mountains, so it sees much shorter use in boost, similar to what the car would see. The only modification that I made was I ported the wastegate, dramatically increasing it's size.
> I have 51 flight hours on the turbo (and many more on the ground) and have had no issues. But the aircraft has been grounded for too many years as other events have consumed my time, but I hope to return to flight this spring as I'm just completing another non-rotary related major airframe modification.
> So the long term longevity of the stock turbo in my lighter duty application is still unproven.
>
> But turbos, while interesting are worthy of an entirely new subject thread. On this subject, I see all your trends are pretty much exactly what I would expect to see. If you're ready and feel everything else is ready it's time to see what she can do in the air.
>
> One thing to consider, and this is only my opinion, but when considering consequences of in-flight failure, I think about the time it takes for that failure to have severe negative consequences. With a failure of the fuel system, for example, the most common result is an immediate engine stoppage, followed by a dead stick landing. I've had a few of those and Ed Anderson has had a few more than that. If you're prepared it's not really that big of a deal, (I was testing the fuel system high above the airport on 2 occasions and once while I was in the circuit, but it wasn't busy), glider pilots do it all the time! Electrical failure can have varying results from an engine stoppage to a minor inconvenience. However these are the type of failures that can result in forced off airport landings.
> But cooling issues are usually far less immediate. If it just a cooling system that is inadequate, then usually power can be reduced to levels producing manageable levels of heat and still safely continue flight and land as planned, then back to re-evaluating the problem using your new flight data. Even with a catastrophic cooling failure such as a blown hose and complete loss of coolant, the rotary won't just quit but will continue to operate far in excess of the time required to execute a safe landing at the airport. If this is done relatively quickly you may not even suffer any engine damage. At worst case you toast the engine, but you and the airframe are intact. But a likely scenario in the event of a complete coolant loss would be an engine rebuild, costing a few hundred dollars and 4-8 hours of time. Obviously this is not something you want at this time, but still, not an unmanageable setback.
> So assuming that you have confidence in the integrity of your cooling system, then this catastrophic failure is not your concern, but rather just the performance of the system and whether it is up to the task of adequately cooling the engine in flight. And it looks good so far but there's only one way to know that for sure. So go fly, stay close. If temps rapidly increase on climb, then before you just terminate flight, see if they stabilize or decrease in level flight. Previously I found that my oil temps were usually good on an extended climb-out but not so good in level flight, but my coolant temps were opposite. Some of this can likely be attributed to the lag time caused by the lower thermal conductivity of oil vs coolant, but I think a larger factor was my previously good looking but not so efficient oil inlet scoop that functioned better at a higher angle of attack and a myriad of other ducting issues (like that I had none on any of the cooler outlets). So during your test flight, even if your temps are higher than you are comfortable with during climb, as long as they are not dangerously high try to extend the flight long enough to collect stabilized data in all flight phases.
> Are you planning on doing the first flight yourself? If not, is your pilot familiar with your engine installation? If not, do you regulations stipulate "essential flight crew only"? If that's the case then I would say that you as the engine builder qualify as flight engineer. This is how I did it and it worked out very well.
>
> Let us know how it goes.
>
> Todd (I hated nosewheel shimmy too, so I got rid of it)
>
> C-FSTB
> RV9 Turbo13B
>
> Todd Bartrim
>
> On Sat, Mar 17, 2018 at 2:28 AM, Stephen Izett stephen.izett@gmail.com <flyrotary@lancaironline.net> wrote:
> HI Todd
> Thanks for the feedback. And yes the manifold pressure does make sense, I was upside down expecting a lower manifold pressure at WOT. Doh!
> I’m colourblind and cant differentiate between some of those colours so was getting confused.
>
> Yes that Cri Cri is an interesting and tiny machine.
> Dawie and Sarki are great guys with heaps of experience and have been so very helpful.
> They bring it out every time we have an open day at our club. The crowds love it.
>
> On another note I’m very interested in the possibility of turboing the renesis in the future if all else goes well.
> What turbo are you using, what level of boost do you use and what hp do you think this is creating?
>
> Thanks again
>
> Steve Izett
>
>
> > On 17 Mar 2018, at 4:29 pm, Todd Bartrim bartrim@gmail.com <flyrotary@lancaironline.net> wrote:
> >
> > Hi Steve;
> > The manifold looks like exactly what I would expect to match your RPM, so no worries there. The temps don't look too bad to me. Possibly your oil cooling might be little low as it begins to increase rapidly when you add power and during an extended climb-out you may see that get a little hotter than you like, but it looks like it stabilizes quickly when you reduce the power.
> > If everything else is performing well (fuel, electrical) then I don't see why it's not time to see how it cools in the air. That's a quick plane so my guess is that if you have enough ground cooling for indefinate ground operation, you may find excess cooling (and drag) in the air.
> >
> > But the real reason I'm responding right now is not rotary related.... A JET POWERED CRI CRI???? Holy s**t, what will they do next! So I found the YouTube video of it (VH-ZSE right?) That's pretty cool!
> >
> > Todd
> > C-FSTB
> > RV9 Turbo13B
> >
> > Todd Bartrim
> >
> > On Fri, Mar 16, 2018 at 6:29 PM, Stephen Izett stephen.izett@gmail.com <flyrotary@lancaironline.net> wrote:
> > Hi people
> >
> > Continued testing the Glasair Super IIRG yesterday with an OAT of 70. See graph of 13 minutes of data (Note: temps in C, Speed in Knots)
> >
> > Apart from collecting data on the cooling I flooded my system with adrenaline.
> >
> > On the second run as I hit about 45knots I encountered very high vibration with no warning. I braked and turned of the engine thinking it emanated from the engine/prop.
> > After leaving the runway and stopping for a few moments I tried a restart, and found all perfectly normal. Previously I had encountered huge missing at rpm so immediately thought that was the issue.
> > Having wrongly diagnosed the phenomenon I taxied back and did another run seeking to emulate the fault. Well this time I got up to about 47knots and all hell broke loose.
> > I was barely able to control her, leaving the strip and into the ruff. Over the radio came the call “if you continue with that front nose shimmy you will destroy your aircraft”.
> > Well I had no interest in continuing the testing at that stage but was very thankful for the feedback from someone watching on. With my lack of expertise I had completely failed to realise what was happening.
> >
> > Back to the hangar and pulled the Shimmy Damper apart. Oil had gotten in at some point, so cleaned it up and re torqued the assembly.
> >
> > A friend on our airstrip with extensive experience in many different aircraft (he has an RV8, Longezy, jet powered cir cri, Comanche twin) then took it out with me (data not provided) and he confirmed he thought the aircraft seemed very responsive (shimmy Damper a little to tight now) and proceeded to lift the nose off for the first time under its own power at a little over 50 knots.
> >
> > So some big lessons for me in relation to my expertise and risk profiling.
> > Temps still concerning but I’m wondering if there is enough capacity to attempt flight testing.
> > I would appreciate any wisdom that any of you glean from the log data. (I expected a different result from the manifold readings, so not sure what is going on there)
> >
> > Thanks
> >
> > Steve Izett
> > Perth WA - Glasair Super IIRG with Renesis 4 port, RD1C, EM3, EC3
> >
> > <Testing 16th March 18.jpeg>
> >
> >
>
>
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