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Great info Dave.
I am cheating even more. The Dynon allows me to program in the re-drive ratio of 2.17 into the system and it reads the actual prop speed. The RWS monitor (Tracy Crooks unit) still reads engine RPM. I am training my eyes to focus more equally on both monitors
as a check and balance and in the case of RPM letting the system do the math.
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Ok.. Correct.. oil is measured after the cooler before it goes back into the engine. Are you still using the 4 outlet bulkhead mounted oil filter pedestal? When I left your project build, I'd put a blind plug in one of the inlets, 1/2" temp probe or bushing/probe
combo in one of the outlets, and then left the pedestal with one inlet and outlet reserved for oil flow.
Also.. just for reference purposes 24.7 inches of mercury MAP is equivalent to near wide open throttle/high cruise in a normally aspirated engine.. you should see about 25-26 inches normally aspirated in an efficient intake at wide open throttle.. maybe a
tad more... 29-30 inches of mercury is sea level ambient pressure. A 1.5 lb spring only gives you 3 inches of boost... so at the power settings you are describing you are not reaping the benefit of the turbo yet.. but thats ok considering you are only in the
pattern.
Do some math and figure out what 2400-2500 prop RPM is (cant remember the redrive ratio for you).. also do the same for 1800, 2000, 2200 and just make a cheat sheet and use those for power settings on your next hop. Adjust that prop for 2500 or so RPM for downwind
and patterns and see what your speeds are. Are you using manually adjustable or "constant speed" functionality on the IVO? Full fine manual is fine for starting off on the ground but once you get to flying speed/positive rate of climb you dont need that fine
a pitch unless you are doing a VX climb trying to outclimb an obstruction.... rough starting points to figure out your unboosted cruising regimens will be prop speed of 2000 rpm and map of 20 inches... and 24 inches then do the same at 2400 rpm at 20 inches
and 24 inches.. look at the difference in speed, and NOISE. You can play with power settings above 25 inches/boosted power later in your flight test but get some basic flight test numbers down pat. I'm extrapolating the numbers that I used in my instrument
training in a piper arrow.. its not the same plane nor engine, but its a starting point if you dont have firm numbers already established.
When I was in the arrow, high cruise was 24"/2400 rpm, low cruise was 20"/2000 rpm.. if I remember right the 20/20 gave me 90 knots level and then with the landing gear extended it put me in a perfect glideslope descent at those settings/trim. I'd be curious
to hear what speeds your bird gets with those.
Remember: Adjust your engine POWER with your throttle and adjust your engine SPEED/prop speed with the prop control. Full throttle with fine pitch is great for making noise. Pull the RPM down while maintaining MP and you will really pick up speed. I dont know
what you've done recently, but I do know all your prior flying before I left the project was fixed pitch prop and the adjustable prop adds a little bit to the mental game. If what I'm talking about really doesn't make much sense, go talk with Dave G in his
RV and get him to take you up and show you what its all about so you can wrap your head around it.
Good luck.. keep it coming..
On 6/10/2012 2:52 PM, Chris Barber wrote:
Ok, here is new information to me. I posted on the Velocity list regarding my oil temps and was informed that oil temperature should be measured coming OUT of the coolers, not out of the engine like I have set up.
This is just the opposite from the way the factory has the coolant plumbing run as the stock coolant temperature sensor is near the thermostat housing as it comes out of the engine and into the radiator. I do not know where the stock oil sensor is located
(if I did, I now forget) but Al G. and John Dibble state the temp should be taken for oil coming out of the coolers. Heck, if this is the case, my oil may be quite a bit cooler than I was thinking. Opinions please. It should not be too difficult to add
a sensor to where the oil enters the engine. Don't know if the Delta will be much, but perhaps enough....
What say Ye?
Chris
From: Chris Barber
Sent: Sunday, June 10, 2012 1:26 PM
To: Rotary motors in aircraft
Subject: RE: [FlyRotary] Re: First flight - Velocity N17010
I reviewed my very short and shaky video more. On Downwind, it shows a GPS speed of 127 kts. The rotary is turning at 6870 RPM (up about 600 RPM from static) with a MAP of 24.7 (1.5 lb spring in the waste gate). Coolant Temp was 187 degrees and oil temp
was 224. Oil pressure and Coolant pressure numbers could not be read but the "gauges" on the Dynon were in the green.
A few minutes later I was able to get another picture of my engine data taken as I was rolling off the active. These reading are about 30 seconds after the wheels touch down. I know it is 30 seconds since I can hear the wheels touching the pavement since
my I-phone continued to record even though it was face down in my passenger seat. Engine RPM was 2489 and the coolant was down to 175. More interesting was that the oil temp had already dropped to 204 (20 degree drop). Yeah, still higher than I like but
a pretty big drop a matter of a few minutes. I do think oil takes longer to read delta T's than coolant...but I could be damned wrong on that.
Perhaps I just noticed the oil enough after a full power climb before it had a chance to adapt and cool a bit??
Chris
Congratulations Chris! I knew you'd do it this morning. Please consider yourself hugged by both of us.
What wastegate are you using with that spring?
Chrissi & Randi
www.CozyGirrrl.com
CG Products, Custom Aircraft Hardware
Chairwomen, Sun-N-Fun Engine Workshop
Didn't notice MAP. Since I am concerned about detonation I have the weakest spring installed. It is 1.5 lbs.
Sent from my iPhone 4
YAA-HOO Chris !!.................Congrats and keep the reports coming............Be interested in if your oil temp was just
hi power takeoff temp that would come down with reduced power and more airspeed............Did you notice what
MAP was (amount of boost) ??......................<:)
Kelly Troyer
On Sat, Jun 9, 2012 at 12:24 PM, Bobby J. Hughes
<bhughes@qnsi.net> wrote:
Congrats Chris. Be safe and keep the reports coming. Does your Dynon have ant data logging capability?
Bobby
Sent from my iPad
June 9, 2002 - A trailer pulled up in front of a simple but comfortable home in Houston.
Lots of trails, tribulations blood, time, money, recreation, education, fun, friendships, anger, frustration, problem solving, sweat, pondering etc....repeat and repeat again and again.
Fast forward (it did go fast)
June 9, 2012 - Ellington Field - A lone, very nervous man arrives at the airport shortly before 0900 hrs. Pushes onto the ramp the contraption composed of fiberglass, metal et al and the ingredients listed above. He sits
down and writes a simple holographic (hand written) will and short note with information to call "Mom" and work. Calls tower to relay intent via the phone.
Preflights the contraption. Gets in, goes though basic Checklist. Cranks up the engine, which fires right up at about 0920 hrs. Taxi to Juliet. Calls tower to verify intent and to taxi to active, 35L. Taxis to Taxiway Echo. Checks temps. Pushing 195 with
OAT reading 95 degrees (geesh it is only about 0930 hrs).
Cleared to take active and hold. Taxied out. Lined up castering nose wheel down center stripe. Cleared to take off. Added power and engine smoothly ran up. Airspeed coming in. 30 kts...50 kts ....60 kts, approximate rotation speed. Lots of runway (9000
ft).....hold it....70 kts....72 kts... Slight pull on the yoke....AIRBORNE!!! Leaped into ground effect. Screw this, pulled back on yoke and I am climbing. Jiggled the yoke a bit to verify control authority.
Climbed to about 400 feet and turned right pattern to crosswind. The Dynon altitude and airspeed seem to be working. That's reassuring. Pattern altitude is only 600 feet and I was there already as I turned to downwind. Leveled off and noticed the clouds
were lower than reported and appeared on the ground. Also, noticed coolant temps had dropped to 190....but oil temps were flashing at me and had reached 225 (synthetic Royal Purple). Damn. Ok. Fly the airplane, the oil is not at not a critical level. , but
let's just finish the pattern and land. I grabbed my phone while on downwind and attempted to record some data but while I can hear the engine the video is awful....uh, in my defense, I was a bit distracted and way more concerned with flying. I called the
tower and informed them I was coming in. I think they were looking out for me since as I turned to base I noticed the fire department staged just off the runways threshold
I noted I was a bit far out on down wind so I stared easing over to turn base. Wow. I really overshot it as I blew by the runway and had to use full right rudder to get back to the runway. I wish I had had more rudder. In hindsight I think I was not using
much aileron as I was cognoscente that I had no idea of stall characteristics so I did not yet wish too strep a turn. I was able to get over the runway and dump some altitude as I got over the numbers and pulled power. Crap, I am fast. I am lined up and right
on the numbers but at 95 kts. I come and touchdown and bounced. Pulled power to idles and settled down easily but fast at 90 and rolled out and exited at Delta. The tower was clearing me back to the city hangars as I was exiting the active. I taxi back and
noticed the oil temps had decreased but I don't recall how much, just noticed they were lower.
I got back to my hangar and popped the door and shut her down. The engine went silent without any hissing or gushing.
I called my mom.
I am mowing informing the world.
I did a walk around and did not see anything missing. I am about to pull the cowl and check things out.
I did notice I did not develop a slight hand shaking untill after I landed and exited the aircraft. ;-) Hey, how about that, it really is an aircraft now. Ten years to the day following delivery.
Thank you for your support.
Christopher Barber, JD
Houston, Ellington Field (EFD)
Velocity N17010
Turbo Rotary 13b
RWS Re-drive and engine computers
Dynon Skyview
Mistral intake
Sent from my iPhone 4
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