0-235 L2c RPM

[Anonymous]

The tach is asteam gage type with a sending unit.

Yes I have wheel pants but they are the original football shape type.
I'm down for a couple of weeks repairing the radio & will run some flight tests when I'm up & running again.
Rick

[Jeffco]

Dave
I have an 235 LC2 with a Catto 3 blade.  I see 2500 static and up to 2900 at full throttle at 4000 ft.  No wheel pants or gear fairings so I am slow compared to most Longs, I see 135 kts indicated maybe 140 if it's a little colder outside.  My brother lives in Eugene and I fly her up there once in a while.  Maybe we could get together next time and compare notes.

Jeff
Long ez n141
Hawthorne airport
serial number 26 still going strong. 500 hours  875 lbs mt

[ozi ez]

Hi

For comparison, I have and 0-235 L2c long ez with a 60 x 70 prop, ram air, 830 lbs dry. I see 2420 rpm static and cruise at 161kts at 2700 rpm at 8500 ft. climb is 1600 fpm sustained out of 2000ft when light.

regards

[Dave in Eugene]

What airspeed are you using for 1600 fpm?

Dave

[Dave in Eugene]

Rick,

What RPM are you getting at full rich, carb heat, idle...? mine is about 700RPM maybe I'll bring it down just a hair.

Really enjoying the airplane.

Dave

[ozi ez]

Hi

1600 fpm climb at 90 kts with 60 litres of fuel aboard the pilot and no baggage, with an air temp of about 18C and the QNH of about 1020mb

Hard idle is about 760 rpm when warm and a little faster when cold.

Ram air helped by about 50 rpm static and the prop added about 15 kts over the BT 62 x 66 climb prop.

[Anonymous]

Hey Dave

At Idle I'm seeing about 850 rpm, full rich, no carb heat. This is too much as it keeps pushing me down the runway. I had it set to 650 on the old engine but I will leave it for now untill I get  few hours on the engine.

I don't think it will hold 650 right now & I'm not going to chance it just yet.

Boy the numbers were a little surprising on the Cato prop and 160 Kts @ 8,500 ft.  My rewiring of the radio is done now so I will try to get some more numbers for you.

Rick

[Dave in Eugene]

Wow...nice prop... Isn't there a waiting list for those?  congrats on your radio...nice to have stuff working,

My next task is rain proofing my plane. i have a big gap in the front of the canopy and want to keep water out of my panel.

Dave

[rglos]

Dave

Opps, sorry !

I did not mean to imply that I had the catto Prop. Nice thought though.

Radio works, intercom works, all new wiring etc.

I'm off next week and will redo some of these numbers.

Can't see how you get 161 Kts out of a O-235 But If our friend in Europe says so then OK

Rick

[ozi ez]

Dear gentlemen,

 I know that 161 kts out of an 0-235 sounds a bit unlikely, but it turns out to be true. Let me tell you how it happened.

Originally I had a B&T 62 x 66 prop that gave about 143 kts at 2700 rpm but i noticed that by allowing the engine to rev out through 2850 rpms and higher only about 5 extra knots was available. This is not what you would necessarily expect as the 100 rpm from 2600 to 2700rpm gave just over a 10 kt increase in speed. Something fishy going on here!

Taking the prop off and measuring the pitch at 4 inch intervals radially showed a pitch that varied somewhat erratically from 75 inches at the root  through 65 inches at 2/3 rds radius to about 55 inches at the tip. A bit of calculation showed that at 2700 rpm and 143 kts, the tips were flying at -12degrees incidence. This tends to explain why my long Ez wouldnt go any faster, as at higher rpms the tips were starting to oppose the rest of the prop.

At this point a good friend stepped in with a loan of a "Henry"prop from his own soon to be finished Long EZ. Measuring this prop showed a consistent 68-71" pich at all stations, so a copy was made for experimental purposes. Initially at full diameter of 63" my engine bogged down at about 2200 rpm static and wouldnt get much past 2600 rpm at any altitude. Not good, but the airspeed was 153 kts! Worth persevering with.....

Then followed a number of sessions of reducing the diameter by 1" at a time, fining the tip profile and rebalancing, until the static rpms came up to 2370 and the airspeed was at 157 kts at 2650 rpms. At this, it was till a little difficult to get to 2700 rpms at 8500 ft.

The next fix was a home brew ram air system that increased static rpms to 2420. Now I can get to 2800rpm at altitude anytime! Some selective polishing and aerodynamic tweaks have yielded  the extra knot or so to give me 161 kts at 8500 feet at 2700 rpms, though from habit, i do cruise at 2650 rpms and 158 kts at 8500 feet, generally.

best regards

Carolyn

[Dan Patch]

Carolyn,

Nice report!  This is the kind of useful information on what you measured, conclusions drawn, modifications made, and the results of those modifications that really helps others determine what might be checked on their planes, and the degree of potential improvement.    

[rglos]

Carolyn,

Great report and very useful.

I'd bet a bunch of your fellow EZ drivers are really thinking hard including me.

Thanks again

Rick

[strider]

Man, our little VariEze must be so draggy! We recently had a very good mechanic go over our O-235 L2C during our Condition Inspection, and it is now running better than ever. Our climb prop is a Culver 60 x 65, and it was turning 2,800 rpm at 8,000 ft, with speed of 130 kts. Static rpm was 2,500.

So I put our Culver 60 X 67 cruise prop on the plane. Static rpm is 2,400, and top end is not 2,700 at 140 kts. No wheel pants quite yet, recently installed the TE Fences and Vorts. Nose wheel-well is made for a nosewheel door that we do not use. And I think the engine has too much right-thrust. You can easily see the engine angle with the plane parked, and it always turns right (yawing) while cruising.

Seems like it's the slowest EZ flying ...

[Dave in Eugene]

Ever gotten scared on take-off?

The other day I took off with a 165lb friend in the back and 25 gallons of fuel. I way about 175. I think we ate 2,800 feet of runway on a 3,500 runway. altitulde 535 ASL and temps in the 70's.

Makes me real thoughtful about High hot heavy and humid.. Also makes me thoughtful of an 0-320!

i would appreciate experiences and thoughts.

Thanks,

Dave

[aaronh]

I've had one take off that gave me a pretty good scare... off meadowlake field. It was not the warmest of days.. around 55 deg. I had about 1/4 tanks and a pretty light pax at ~130lbs. Meadowlake is at 6800' with 6000' of runway. PLENTY for a moderately loaded longez w/235!

I had a stiff cross wind. Nearly at 20knotts. It was also not consistent. I have found the ez to handle pretty well in x-winds overall so.. full throttle I was rolling. Not very straight though. full left pedal... hmm not enough even over 30mph... hair of brake.. ok I'm straight again. I found myself having to ride the left brake quite a bit. Every time I tried to get off of it I'd have to get back on harder to pull the plane back straight. A bit over mid field I thought about aborting but I had 70mph... another 5-8 and I'm flying. That last 8mph took FOREVER! I burned up 3/4 or more of a 6k' field that day. If I had to abort I'm not sure I wouldn't have been in weeds at the end. Now think if it was hot with more fuel and a heavy pax.... ugly ... real ugly.

I absolutely love my EZ, but a short field performer it is not! It is horribly underpowered at high density alts. And add to a high alt takeoff having to use a brake in strong x-winds..... the long in longEZ is for loooooooong takeoffs.

I'm a bit more conservative after that takeoff. If the x-wind has me too hard on a brake to stay straight, I'll make mid-field my abort point. iI I'm not lifting off by then, time to pull that throttle and use both brakes.