Waiters 2nd First Flight

[Lynn Erickson]

waiter, seems you have it covered and well thought out. on the infinity gear we had to increase the up pressure to 1200#, the gear would come out under G load at 650. on my gear the up pressure switch is set at 1600#. the pump pressure relief is set to 1650#. the one strange thing I see is that the up pressure increases slowly during a 30 minute flight, up to 2000# with the pump off. still don't know where the increase of pressure is coming from.

[Waiter]

Lynn;

 

I thought about that (G load). I'll look at the pressure tonight and see where its at.

 

I may also reduce the tire pressure, I think I have them at 65psi. Any idea about tire diameter??

 

Tire clearence inside the wheel well is tight. If I were doing this again, I would add 1/4 - 1/2 all the way around the circumference of the well.

 

As for your pressure increase! Could be caused by fluid expansion (Not sure what the expansion co-efficient of 5606 is). If the system is tight, when the fluid expands it doesn't have anywhere to go, so the pressure increases. However, You would think that the increase in pressure would bleed through the pump relief valve. (might be that the pump reliefs at 1650, but there is a check valve that keeps the fluid from flowing back into the pump to be relieved, maybe, kinda, sorta!!!

 

Waiter

[Lynn Erickson]

Lynn;

 

I thought about that (G load). I'll look at the pressure tonight and see where its at.

 

I may also reduce the tire pressure, I think I have them at 65psi. Any idea about tire diameter??

 

Tire clearence inside the wheel well is tight. If I were doing this again, I would add 1/4 - 1/2 all the way around the circumference of the well.

 

As for your pressure increase! Could be caused by fluid expansion (Not sure what the expansion co-efficient of 5606 is). If the system is tight, when the fluid expands it doesn't have anywhere to go, so the pressure increases.

 

Waiter

there are two sizes of wheel wells from infinity the early ones where a bit to small

tire diameter did not seem to change with pressure but take off roll did. I use DOT 5 not that red fire starter fluid, may have something to do with expansion. what would make it expand ? we thought about latent heat expansion. have looked for something heating up the system during flight but it seems that everything gets colder at altitude, even does it in winter. don't see much change until about the 30 minute mark and then it seems to rise in the next 30 minutes

[Cozy Girrrl]

We agree the wheel wells are too tight for the Michelins and we will probably go find a smaller tire before we bother to cycle ours.

...C&R

[Lynn Erickson]

We agree the wheel wells are too tight for the Michelins and we will probably go find a smaller tire before we bother to cycle ours.

...C&R

the michelins are the smallest 5x5 aircraft tire I have found. let us know if you find a smaller one. we had the same problem on our Glasair I but the michelins are just small enough to make a difference

[argoldman]

One thing you might try, or at leaset consider is the Lamb tire (or it's replacement. It is smaller than the 500X5, and if memory serves me correctly it will fit on the same wheel. (at least I think as I was able to mount 500X5s on the wheel that originally had a lamb tire on it.

[Lynn Erickson]

One thing you might try, or at leaset consider is the Lamb tire (or it's replacement. It is smaller than the 500X5, and if memory serves me correctly it will fit on the same wheel. (at least I think as I was able to mount 500X5s on the wheel that originally had a lamb tire on it.

the lamb tire would fit but the Infinity gear was suppose to allow the use of the larger tire for rough landing strips.

[Waiter]

I have a set of Lambs at home, I'll take them over to the airport for a photo shot (size comparison)

 

I'd like to stick to the larger original tire, I'll put the plane on jacks tonight and see if I can duplicate the problem.

 

 

If DOT 5 has a negative expansion cooeficient, or some wierd curve like water, this could do it.

 

i.e. I'm looking at the table for water, the coefficient crosses zero at about 4 Deg C.

 

At 4 Deg C its +0.00000031 At 3 Deg C it goes negative, -0.00001592.

 

Waiter

[Waiter]

I just talked to the folks a Desser Tire, He said there really isn't a spec on OD of the tire, but generally, they run about 14.2 inches for the 500x5.

 

However, he indicated that the Goodyear Flt Spec II, because of its contour may be slightly smaller in diameter, so I ordered one to test. I'll let you know how it measures up.

 

In the mean time, I have two options;

 

1) Reshim / machine the half fork to move the wheel forward in the well. (Not a big deal, I have access to the mill to do this and have done similiar work on the half fork to correct for toe-in)

 

2) Use the Lamb Tire.

 

Of course, all this depends on verifying that the tire is indeed hitting the aft portion of the well.

 

Waiter

[SAF_Zoom]

If you can't get a chase plane to come up with you, you could use a cheap back up camera (they attache to the license plate) that the sell now. Just fixe it to the nose gear leg. This should give you a good rear view.

[Waiter]

you could use a cheap back up camera

Since the planes flying backwards, that should work great

 

(I have a lipstick bullet camera on order. I'll attach it to the speed brake so I can record the main gear retract, or point it forward and record the nose gear retract.)

 

Waiter

[TMann]

Waiter..... what tires are you using?

I think JD says Michelin for this gear (that's what I have for mine.)

 

I measured the inside diameter of my wheel wells and they are 14.5 in diameter. Is that what yours measure out as or are they smaller?

[Cozy Girrrl]

I had this discussion with JD a couple of years ago, he said he had the spec from Michelin and that the current tires are at the max.

 

Waiter, the gear is supposed to move forward when it is pressurized. That is our largest concern. I worry about a dirty tire coming up and eventually abrading through the wheel wells

[philc1]

My project still has its max altitude limited by the sawhorses I'm using but I have played the tire size game. If the tire is hitting the well, a different model of tire may indeed help.

 

The Michelins and Matco's I'm using are both larger than the Goodyear Flight Custom II and Cleveland combination they replaced. I talked with the Michelin Man about the inflated diameter of the 5.00 x 5 Michelins and he said there was an acceptable range for production and that the set I had was at the upper end of the range.

 

I wanted to use the Michelins and they were a bit tight in the wells for my comfort, so I sliced up the wheel wells, expanded the diameter and extended them the full depth of the strake.

 

If it's a matter of the tire hitting the aft edge of the well rather than a diameter issue, I wonder if it would be acceptable to install a shim on the trunion pin to move the entire strut forward.

 

Phil

[TMann]

Girrrls, Phil ,

What do you see for an inside diameter of your wheel well?

[longez360]

I use 8ply lamb tyres in place of 500x5's because of the statements Burt made at an Oshkosh forum. He asked all those who flew 400x5's tyres on their EZ's to raise their hands, and when we did, he mentioned that the testing on SpaceshipOne surpirsed him as to the capabilities of the tyres. He quantified his statements against 500x5's.

 

In terms of soft/rough field operations, the EZ family are the wrong aircraft for a variety of gear and non-gear related reasons. It's the primary reason why they were built in only limited quantities Down Under. We have a number of EZ's that operate out of grass strips, but we are a relatively dry continent and without walking the strip first, I wouldn't fly into one even here.

 

I'd use 8ply 400x5 chen shins on a Infinity Retract system, whilst keeping a keen eye on quality control, and let the certed ship drivers pay for the expensive 500x5's.

[Waiter]

Heres a photo of the aft part of the cowl, I'm holding a piece of the cut off cowl so you can see the Before/After.

 

Before the cut, there is about 3-1/2 clearence, with the prop in the takeoff mode. (This is about 2-1/2 when the prop is in the cruise)

 

After the cut, the measurement is 5 inches in takeoff, 4 in cruise.

 

This cut made a significant improvement in noise level, and a small improvement in temperatures.

 

( I forgot to measure the Wheel Well, I'll get it tonight)

 

Waiter

[longezdave]

I was at Oshkosh in 1999 and ran into Klaus. I struck up a conversation that ended up at my Long EZ. He was a bit interested, since I told him that I had bought my EI and prop from him. I asked if he had any advice for me. He mentioned the cut-outs that I had made in my cowl on both sides above the cylinders. He said the air coming up out of the vents would be somewhat like two 2 x 4s (boards) sticking out of the cowl. The high speed air comes along and slaps into the low speed air spouts at the vents and would cause a lot of drag. The other thing he mentioned was the clearance between the back of my cowl and the prop. He explained about the wave in front of the prop slapping the back of the cowl. He didn't mention anything relative to cooling, but did mention opening the clearance would reduce cockpit noise level and help prop efficiency. I grabbed a pencil and asked him to make a mark where it should be cut. He didn't want to mark on my cowl. I got him to show me where and I marked it. I sealed the vents up and cut the cowl to the mark on both sides as soon as I got home.

[JLKnolla]

Have you considered a flow guide (like a reverse spinner) for forward of the spinner Waiter? I know Klaus sells them, and LongEZ.com too.

 

I would suspect that to be more important given your new DD cooling scheme - maybe exhaust augmentation too depending on where your pipes exit the cowl.

[Lynn Erickson]

I was at Oshkosh in 1999 and ran into Klaus. I struck up a conversation that ended up at my Long EZ. He was a bit interested, since I told him that I had bought my EI and prop from him. I asked if he had any advice for me. He mentioned the cut-outs that I had made in my cowl on both sides above the cylinders. He said the air coming up out of the vents would be somewhat like two 2 x 4s (boards) sticking out of the cowl. The high speed air comes along and slaps into the low speed air spouts at the vents and would cause a lot of drag. The other thing he mentioned was the clearance between the back of my cowl and the prop. He explained about the wave in front of the prop slapping the back of the cowl. He didn't mention anything relative to cooling, but did mention opening the clearance would reduce cockpit noise level and help prop efficiency. I grabbed a pencil and asked him to make a mark where it should be cut. He didn't want to mark on my cowl. I got him to show me where and I marked it. I sealed the vents up and cut the cowl to the mark on both sides as soon as I got home.

and so what is the moral of the story? you left us hanging

[longezdave]

I wish I could tell all that I had precicely tested before and after my changes (suggested by Klaus) that I made per Klaus's suggestions and that I added X knots. The truth is that my uMonitor was giving me incorrect CHT data (I built it - my bad) in the early days. With the incorrect data, I never made any meaningful performance tests because I thought that any performance tests would be over-temping my engine due to inadequate cooling. Therefore, I never "pushed" my engine until after my rebuild, circa 2008 that included checking the calibration of my CHTs on the uMonitor. I found that the uMonitor was off significantly and I made resistor changes on the uMonitor to correct the callibration. My check of CHT callibration was done by putting one of my CHT probes in oil. The CHT probe was wired (mechanically/thermally) to an RTD probe (recently calibrated) and placed in oil that was heated by a torch. That was how the descrapancy was found and corrected. It was only after correcting the CHT indication on my uMonitor that I was willing/able to push my engine. Right or wrong, since correcting the uMonitor error, I have entered five races. During those races I have pushed my Long/engine as far as it can be pushed and have done well - http://www.sportairrace.org/id257.html including my best race speed of over 204 MPH. I hope that running at about 374 F on the cold side (updraft cooling) has not caused rapid cylinder wear.

[Waiter]

OK,

 

Left Gear not fully retracting - Solved

I have one of the original gear sets, there is NO room in the wheel wells. i.e. With the Michlen tires, I have about 1/8 clearence all the way around. I have a new Goodyear tire I got from Desser, but I'll wait until I replace the Michlens as long as I don't have any more problems.

 

The left main was hitting on the aft lip and kept it from fully retracting. I machined a slight angle on the Half Fork (an AN 10 thick washer thicknes) This tilts the left wheel forward about 1/4 inch. hence moving it forward about 1/4 inch when retracting. I had done this to the right side a couple years ago.

 

The gear now fully retracts with no problem.

 

 

 

Main UP switch not working - Solved

 

I had the wrong logic on "Tilt" switch. This switch is made when the aircraft is NOT tilted (parked on its nose). This switch is one of the ground interlocks that prevents inadvertent main gear retract when the plane is parked on its nose.

 

Gear / Canopy Warning horn not loud - Solved

 

I bought and installed a car horn ($18.00), Works great. The horn is loud, regardless of speed, wind noise, etc. It does get your attention.

 

 

 

CHT / Oil Temperature igh - Solved

 

The left gear not fully retracting was blocking the oil cooler intake. Oil temp is now sitting at 190F with 250F during prolonged low speed high HP - touch / goes.

 

I never seen the CHT go above 400F(85 deg OAT)

 

 

FLIGHT NOTES - When the gear is fully retracted, there is a little kick in the pants and a distinct pitch up

 

 

Landing - Visual queues seem to have changed (Seems to touch down a little higher) A made a couple really good SLAMS (unintential) , Kind of like a Carrier landing. Nothing broke or bent,

 

Waiter

[Firefly-YCTTSFM]

Heres a photo of the aft part of the cowl, ... After the cut, the measurement is 5 inches in takeoff, 4 in cruise.

 

This cut made a significant improvement in noise level, and a small improvement in temperatures.

Wow... I'd have *never* thought that 2 inches would've made such a difference. I can understand the cowling / prop spacing being important, but it's not like you had a particularly ugly trailing edge.

 

Thanks for the info!

[Waiter]

Wow... I'd have *never* thought that 2 inches would've made such a difference.

As I mentioned, I've seen this first hand back in 1996 during my first Phase 1. (I forgot about this until I made my first flight a couple weeks ago, Deja-Vue)

 

After the 2nd first flight, I looked up inside the cowl. I could see exhaust residue on the lower left and upper right inside and outside surfaces of the cowl. (Darn, Get out the SawZaw.)

 

Keep in mind that the Propellor is an airfoil, just like a wing.

 

As the wing is flying through the air, the air above and below the wing is compressed and moving up and down to get out of the way of the wing. ( I seem to recall 2x the cord is the compression distance used)

 

Now turn this airfoil 90 degrees. The top of the airfoil is now pointing forward.

So, (looking forward from the back of the plane) as the propellors airfoil is moving down (on the left side) and up (on the right side) the compressed air is pushed forward (2x cord). If the cowl is close enough, this compressed air will hit the cowl and can actually be pushed up inside the cowl as the airfoil passes by.

 

 

The only solution is to get the cowl away from the prop.

 

(hope this helps a little)

 

Waiter

[Waiter]

Several people have asked if I've taken any Airspeed data yet?

 

Yes / No, kinda.

 

As I resolve issues during the flight testing, I'm becoming more comfortable with the aircrafts handling, and building confidence in its performance.

 

 

Of major concern, particullarly the EZ, are the CHT and Oil Temperatures.

 

After resolving several issues, I'm happy to report that these are well under control, and the performance is predictable.

 

AIRSPEED

 

Keep in mind that I'm just now starting to take a carefull look at the airspeed / altitude instruments. Particullarly the high speed, high altitude regions.

 

Both, Airspeed and Altitude seem to be reading low. I'm getting conflicting readings between the Dynon and the GPS.

 

I need to take the Manometer over to the airport and re-calibrate pitot and static systems, and look for any leaks.

 

Waiter