#### Re: Flight report

Jay Scheevel

Hi Vern,

Forgot to mention that my redline is 3300 rpm. The factory dyno indicates 121 HP at 3300, and the torque curve is relatively flat, so HP scales pretty linearly under load. Using fuel consumption (when leaned to best power), you can get a good idea of HP being generated under prop load. The formula for this computation is [12 hp/gallon/hour]. This is fairly accurate for most engines, since energy efficiency is nearly the same for any normally aspirated engine. Using this method, my Jabiru power output (percent of max power) turns out to be the fuel flow in (gph X 10) which is easy to do in my head in the cockpit. So, when I was at 17,700 DA, and burning 3.9 gph, I was getting 39% of max power, or 47 HP.

Here is my power chart using two different methods. That simple fuel consumption method is in the right column, the other formula is shown at the top and computed in the table assuming a standard day. The region on the table outside the red dashed outline, has essentially no risk of detonation, regardless of leaning condition. Inside the outline, detonation risk increases towards the upper right, although with my 7:1 compression ratio, the risk is still pretty low.   I keep a copy of this table in the operator documents.

From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of Jay Scheevel
Sent: Monday, June 14, 2021 10:53 AM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Flight report

Hi Vern,

Paul Chernikeeff, the founder/owner of Rotec told me that the Rotec TBI is an exact copy of the Ellison. Elision went out of business and their patent had run out, so Rotec, just copied it and started marketing it and using it on their radial engines. I am very happy with it. Only shortcoming is really just a shortcoming of the Jabiru induction manifold, which is too small to get uniform fuel mixture. On a Lycoming it would be much better, maybe even as good as EFI for mixture control. Someday, I may fabricate a larger induction system. Jabiru actually makes a larger one for their current generation of engines.

Putting in the Jabiru, which is lighter than the O-200 required an engine mount that put it slightly forward. It is narrower, so a commensurate reduction in the prop extension meant that it could fit under the Q-200 cowling. I modified that for the radiator airflow. Luckily, Paul Spackman had already installed a Jab 3300 in his Q2 and the guy that fabricated his engine mount built one for me also. Paul’s was air cooled and he had the GU canard and it was very fast. The current generation of Jabirus have heads permanently fixed to the cylinder like the Lyc/Cons so water cooling is not an option. If you are considering the Jabiru as a powerplant, there is lots more you should know before making that decision. Contact me offline and I can give you all the pros and cons.

Cheers,

Jay

From: main@Q-List.groups.io <main@Q-List.groups.io> On Behalf Of smeshno1@...
Sent: Sunday, June 13, 2021 7:57 AM
To: main@Q-List.groups.io
Subject: Re: [Q-List] Flight report

Quote from one US supplier, whom I trust and know personally.

"This is an outstanding carburetor, based on the initial Ellison design. It works equally well as gravity feed or pump fed. Although it is referred to as a “Throttle Body Injector” it is technically a diaphragm control, flat slide, float less carburetor. It will not pickup if subjected to negative G’s. It has full authority mixture control, and is known for very accurate mixture distribution. The ‘button’ on the diaphragm can be used as a primer, and the carb also has a bypass port to further prevent hard starting when hot. An affordable, brand new carb, in production many years and based on a very well proven design. I am a US service center for these carbs, so they need not be returned to the factory if any service is ever required.-Made in Australia."

I've seen the 3300 on Zenith 701 and 601. Owners (West Coast and high DA bases) I spoke with were pleased with the powerplant. I suspect your actually obtaining around 107hp constant at 85% throttle setting (that would be 2500 to 2550 RPM). Your redline is 2750 RPM if I understand correctly.

A well thought out powerplant and it has proven itself to at least 18,000 ft PA.

For those that might choose this engine, what were your CG issues (and corrections) as compared to the O-200?

I ask because the availability of Certificated Continentals and to some degree Lycoming (and Franklin) which we had in droves back in the 1980's is already a challenge 40 years later. I have made my decision on this topic but not everyone was hacked out of the clay to be a gearhead as I was. I own the equipment to back up the tasks as well so that is yet another factor.

I admit to be a rather serious chicken in the air, and over ruff terrain even more so. I've had a CFI on Bi-annual review ask me why I was not having fun. He was a bit younger than I am (about 30 years). It's not that flying isn't deeply satisfying to me..it is!..but I realize my personality becomes quite stoic once the pre-flight begins. I guess it's the responsibility part that drives my seriousness. I was trained in a more or less military manner..my first CFI was a WW2 and Korean War Veteran Instructor known to be strict. At the time exactly what a wise assed 21 year old wannabe pilot needed. I crossed my 40 hours on my exam. Soloed at just over 5 hours. Fitzpatrik was a tuff old bastard but he put the right kind of fear in my kraut head right off the bat.

Flatland flying is at least a bit less tension, just give the storms a lot of respect. Lots of (hopefully) reasonable places to park below if need be. Travel out of the Midwest is nice when aviating because the hours of bored driving in mostly dull scenery is avoided. I was born and grew up my early years mostly in Kansas and Florida. FLAT.

Now I live in Eastern Oklahoma which is a lot of lakes,trees,and hills. Not so many nice parking places if need be.

I'll be flying off my 40 hours at Cushing airport. Flat.

Vern

From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Sent: Saturday, June 12, 2021 10:43 PM
To: main@q-list.groups.io <main@q-list.groups.io>
Subject: Re: [Q-List] Flight report

Hi Vern,

Flying behind a modified Jabiru 3300.  (Six banger, horizontally opposed). It is modified with liquid cooled heads and I have a Rotec throttle body injector, so normally aspirated. Mike Dwyer asked about the ignition. I have one magneto and one fixed advance electronic ignition, so basic stuff on both fuel and ignition.

Yep, need to be vigilant of winds and DA when operating in the mountains, but the scenery is great!

Cheers,

Jay

On Jun 12, 2021, at 2:59 PM, smeshno1@... wrote:

﻿

Yes indeed! So the numbers prove that the Q design is still a serious CAFE contender. Jay, your flying with which powerplant? Normally aspirated (I presume), carb or injection?

It is important to have the actual service ceiling known in the aircraft operations info. I lived in the Taos area for quite a while. Better know your location and winds aloft ALL the time. Too many flatlanders ended up permanently parked out on the slopes because they let the Ego take over at pre-flight! I learned to fly in Arkansas so for me it was a transition, and again when I lived the Pacific Northwest (sometimes busy as I was flying from Paine Field in Everett where my employer at the time flys BIG airliners to and from).

When the day comes for this test I'll be hoping to see some similar numbers! 😊 Big grins. Squeekers are always good after a challenge flight.

Vern

From: main@Q-List.groups.io <main@Q-List.groups.io> on behalf of Jay Scheevel <jay@...>
Sent: Saturday, June 12, 2021 3:29 PM
To: main@Q-List.groups.io <main@Q-List.groups.io>
Subject: [Q-List] Flight report

Took a flight this morning to check out my service ceiling. Sam mentioned that he thought I should do the service ceiling test during his comments at my hangar tour in April. I had filled the O2 bottle anticipating coming to Kevin’s fling in May and I never made it there, so I had some oxygen to experiment with. Took off with about 15 gallons of fuel and only me on board. The takeoff was at 6100’ DA and it got off smartly in less than 1500’ of runway.  I kept climbing steadily between 500 and 300 fpm showing around 105-110 mph IAS or around 125 TAS. Got up over 15,800 feet pressure altitude, and when it  slowed down, I grew bored of climbing at only 100 fpm, so I terminated the experiment. That was about 17,700 Density altitude, so I think I could climb to 18K pressure altitude on a standard day if I wanted to. At this point I pushed the nose over and got it trimmed up to fly level at a little over 15,800 PA. I was able to indicate 107 mph, which translated to 141 mph TAS and I was burning less than 4 gph! The wind was from the SW at 29 mph, so if I had turned to the NE and headed over the hills, I would have had minimum 2500’ feet clearance over the highest peaks and done 170 mph ground speed…at 4 gph, that would be very economical. The aircraft handling was solid during the entire flight. Controls were always agile. Also, the powerplant ran flawlessly all the way up and back down with no hesitations, roughness, heating/cooling problems, etc.

My conclusions: This airplane will do anything that I require it to do in order to fly safely in my high altitude environment, and I am very happy with the performance overall. Also, had a nice landing at the end. Smiley face. 😊

Cheers,

Jay Scheevel, Tri-Q2 N8WQ, 151 hours.

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