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First, foremost above all: answer Leni's tach question.

If you are running an analog, needle tach, assume it is not accurate. Get a tiny tach emediately for a cross check.

Ed,

 

Front strut is 7' 11 59/64" from bolt hole to bolt hole center.

Rear strut is 8' 3 3/4"

Angle from the fuse to the strut is 62 deg. 22' 18"... or roughly 62 3/8 degrees.   I would shoot for 62

 

You only have 1 deg. of dihedral ??

 

That one degree is about what the manual says, I THINK? The L-19 had about 3 degrees, I think.

I will check the books on that. Believe one of my manuals calls for a 3/4 or 13/16 spacer on a 4 foot level on front spar. You can check those figures and see what the angle is.

I wonder if you can have too much / too little? Got to go read my design book again!

Your CAD guy saved me a mountain of figures - Please thank him for me.

What is your dihedral? I can always change mine before making struts, but would need new figures.

Thanks a bunch,

ED in MO

I am confused.. if its fuel delivery, then there would have been a significant drop in RPM... Did the RPM hold at 6500 yet you suddenly stopped climbing and lost forward speed even with it turning 6500 still?

 

I had this issue once.. down drafts and micro bursts can be quite the bitch!  I took off from a 6000' long lake with my cousin in the plane, take off was normal, climb was around 500 FPM till I got over the far end of the lake.  We were at about 500' with the engine turning full RPM when we started dropping at 600 fpm hanging onto a 50-55 MPH airspeed.  I slipped it between the powerlines and the trees on about a 60 deg bank trying to get aligned with the highway.  within seconds we were over the highway at about 10' off the road looking at the headlights of a semi truck 300 yards off.  I got to the edge of the down draft / micro burst about 80 yards from the semi as smoke rolled off his tires, I climbed out and cleared the trailer by about 20'... It took us about 5 minutes before we even looked at eachother and started giggling like little school girls... you know, that nervous laughter when you know you were seconds from death but you cheated the grim reaper yet again...

 

Since that day, if the wind is blowing straight down that lake, I will turn out well before I hit the end of the lake.

Ed,

 

Front strut is 7' 11 59/64" from bolt hole to bolt hole center.

Rear strut is 8' 3 3/4"

Angle from the fuse to the strut is 62 deg. 22' 18"... or roughly 62 3/8 degrees.   I would shoot for 62

 

You only have 1 deg. of dihedral ??

 

I'm going to check the prop pitch but I don't feel like it's going to be a problem. It flew fine a few months ago when it was last flown, seemed to climb around 500-700FPM and cruised at 80MPH. I can't it's too far off.

 

I saw you posted this earlier on the other forum, thats why I'd start with the fuel delivery.

I deleted the other one for ya.  I dont think you can delete a topic.  You can delete a post that you have made, but not a topic.... One of the software quirks

 

1)  Did you loose RPM during the flight?

2)  What Tach do you have?

3)  If you were at 6500 static, then you would have or should have been over reving once you hit about 20-30 MPH.

4)  That do the plugs look like?  with 170s I am going to bet they are nice and black.  170 is what I run when it is -30 outside.  I use 165 in the summer temps about 20 degrees at sea level.

Ed, Give me a few minutes and I will run over and have one of the CAD monkeys lay it out.  It will only take him a few minutes to give you the numbers.

 

Thanks Leni,

I accidently posted this twice - why cant I find the "delete" button on this new site?

Oh Hell - now that I posted this, the danged delete button show up? ?

Don't take much to confuse me!

Ed

Ed, Give me a few minutes and I will run over and have one of the CAD monkeys lay it out.  It will only take him a few minutes to give you the numbers.

 

My trig tables are somewhere buried in my boxes in storage from my move from Alaska.

I have to make new strut brackets and struts since I raised my wings about 6 inches.

I am such a dummy that I don't have a clue as to how to do this with a computer.

Will someone (engineering type, maybe) figure out for me, about what angle the struts will be at now, and approx. lengths?

Any help would be appreciated.

I will try to download a diagram.

Thanks,

Ed in MO

Sounds to me If you had full power at takeoff 6500rpm give or take, and during the climb you stopped climbing, most likely you have a fuel delivery problem. It takes a couple minutes to suck down the header tank, thats why it doesnt happen until your a couple hundred feet off the ground.

 

Pull the gas line off at the fuel pump and see how fast it will gravity feed. Then I'd be looking at all the filters and finger strainers first before messing with the carbs to much.

I'm trying to visualize how to run the gasline into the plane, either at the back of the butt rib or behind the tube at the front of the turtledeck. Anyone have a picture of this area?

 

I've got a few photos of a kitfox but there not the same as the avid

I posted this on TeamKitfox but I wanted some opinions here also.  It's a bit of a read.

 

I have a Rotax 582 with 3:1 Gearbox and a GSC 68" Tech III prop mounted on a Kitfox IV.

 

 

Before the tires left the pavement we ran the engine close to 3 hours (probably longer over a few weeks) and did a thorough inspection of everything, we were within CG and Weight limits and the density alititude was only 2,000ft at 66 degrees farenheight. Alot of precaution was taken. So we are trying to figure out why things almost went horribly wrong.

 

We lined up on runway 24 after warming the engine and performing a runup, we accelerated as normal and it felt like full power, we managed to climb at 50-55MPH from runway 24 at Johnson County Airport in Tennessee (elv. 2,240).  That worked well until about 200-300ft AGL.  The engine was at 6,500RPM's, EGT's were steady around 1,100 degrees and then, we stopped climbing, the rate of climb was around 50ft per minute.  Realizing this my instructor and I lowered the nose and attempted to accelerate, it would not.  The speed topped out at about 58mph.  As we turned crosswind we got a bit of a tailwind gust, 5-8kts at most and the aircraft began descending even at full power and holding 50mph indicated.  We immediately commenced a 180 degree turn into the wind and slowly climbed to 500ft AGL, we then did a 270 degree turn and landed midfield back on runway 24 with extreme haste.  We were both shaken up a bit at the total lack of climb power and ability to accelerate in very unforgiving terrain.

 

The first inclination was that the carbs were jetted wrong.  I checked and we had 170 main jets and 55 idle jets, the needle jet was on its lowest (richest) setting.  I backed the needle jet back to setting 3 to lean it out a bit.  I have since ordered a 160 main jet and 45 idle jets to give a try but they will not be here until friday.

 

The second inclination was to check prop pitch.  I checked it and it was at 18 degrees.  GSC recommends 14 degrees for my setup.  I just finished performing another static check and at full throttle the engine turns 6,425 RPM's which is a tad high according to GSC.  I reset the blade pitch to 19 degree's thinking it would reduce static RPM's to GSC's recommended 6,200 RPM, it did not, in fact we saw a small increase to around 6,500 RPM's static.  This is puzzling, so I called GSC and they told me to try 14 degrees.  It may be possible that we stalled the prop blades trying to turn them at such a high degree of pitch and trying to climb (although very unlikely).  Tomorrow I am going to reset the pitch angle to 14 degree's and see what happens but I feel our static RPM will want to overrev like crazy.

 

The third possibility is that our tach reading is way off, I'm attempting to get my hands on a prop tach to double check our tach readings.  Hopefully I can do this tomorrow.

 

I'm looking for suggestions, advice, experience or any helpful information regarding this issue.  The airplane runs awesome on the ground, makes power, enough so you can hold the aircraft level on the ramp at full power without much effort.  I just don't understand why it felt like we lost power on the takeoff with the RPM's around 6,500 and the EGT's normal.

Very Cool!  Its great to see someone doing more than pavement pounding at this phase of the training.  Thats exactly how my training went.  Nice shot of Jeff flying off into the sunset

 

Jeff and I got out for a little gravelbar practice last night after we put new bungee's on his plane and he finished installing new gas caps on the outboard ends of his tanks, plus replacing all his lexan.  The new tank caps are really nice; a flush design.  Jeff is really learning how to fly his plane very quickly; good landings Jeff!

 

Here are a couple pics.  Jeff should be posting some video soon.

I still have them connected to the cross tube but now working on changing the pedals and building the brackets to place them on the floors.  The Grove sound like a good way to go.  thanks

Paul, I have the Grove gear for 1 thru 4, 1200 GW, with axels and 6" matco wheels and calipers, for sale.

Just in case anyone wants a used set cheaper than new ones.

ED in Mo

Paul,

Although tail wheel castor is a poblem if it comes free at the  wrong time, my conclusion has been that the factory brake pedal geometry causes most ground loops with these birds.  (it did with my first three GL) Do your master cylinders connect to the cross tube or to the floor?  If they are not connected to the floor, a hard rudder input will push the opposite brake into your foot giving brake input that intensifies the ground loop.   Attaching MC to floor reverses the action and drives the brake pedal into the foot that is applying rudder.  This way you get brake assist for rudder inputs.  Although I wouldn't want to press my luck, I'm pretty sure I could now maintain control even if the tail wheel was castoring.  I've seen several members post pictures of this setup that were better executed than mine, so there are a number of good ideas to draw from.  After wiping out my standard gear, I put on grove gear and have never looked back.  (wide stance and puts the load in the right place on the frame)

 

Good luck and be safe.

I still have them connected to the cross tube but now working on changing the pedals and building the brackets to place them on the floors.  The Grove sound like a good way to go.  thanks

Paul, I have heard some really really mixed reviews on the bush gear.. good landings and they work great, bounce one too hard and they bend the fuse.  I think both guys have quit making the gear now due to the number of planes that have been bent up using the new spring gear.  We are in a really busy time at work, but I have one of the engineers working on the loading and geometry issues to hopefully come up with a fix so guys can quit pulling the side of the fuse in when they bounce it in too hard.

 

Sounds good, I will be interested in hearing what you come up with.

I couldn't agree more about the Grove gear, David.  I did the same and my project now has a taller (3"), wider (2-1/2") Grove set for it coming.

 

However, I do agree also with the removal of the unlocking cam on a Maul wheel on these planes during training.  (The first 100 hours!)   I know a multi-thousand hour tailwheel CFI that looped a buddies Mk4 Avid twice prior to removal of the cam.  These planes are short and quick, with no where near enough rudder.  Period.

 

The issue with the brake peddles only exacerbates the situation.

Paul,

Although tail wheel castor is a poblem if it comes free at the  wrong time, my conclusion has been that the factory brake pedal geometry causes most ground loops with these birds.  (it did with my first three GL) Do your master cylinders connect to the cross tube or to the floor?  If they are not connected to the floor, a hard rudder input will push the opposite brake into your foot giving brake input that intensifies the ground loop.   Attaching MC to floor reverses the action and drives the brake pedal into the foot that is applying rudder.  This way you get brake assist for rudder inputs.  Although I wouldn't want to press my luck, I'm pretty sure I could now maintain control even if the tail wheel was castoring.  I've seen several members post pictures of this setup that were better executed than mine, so there are a number of good ideas to draw from.  After wiping out my standard gear, I put on grove gear and have never looked back.  (wide stance and puts the load in the right place on the frame)

 

Good luck and be safe.

Paul, I have heard some really really mixed reviews on the bush gear.. good landings and they work great, bounce one too hard and they bend the fuse.  I think both guys have quit making the gear now due to the number of planes that have been bent up using the new spring gear.  We are in a really busy time at work, but I have one of the engineers working on the loading and geometry issues to hopefully come up with a fix so guys can quit pulling the side of the fuse in when they bounce it in too hard.

 

Randy,

 

Depending on water levels, there are several gravel bars we should be able to get into right on lake creek.  It would be a bit of a bugger to get to the good fishing without being able to fly into the creek.  We can steal one of dans boats and take that up the creek a ways if the water is high enough, but it is still a bit too low on the river to get into the good grayling and trout fishing.  When the silvers are running, we could have a great time in the boat though!

 

We can either land at Bentalit lodge, or land on the little island out in front of lake creek and have him pick us up there.  I will get ahold of him and see what we can work out.  I am ready to get a fly line wet!

 

 

 

That sounds good.  I'll bring the worms...oh, I guess I was having a flashback to "A River Runs Through It". 

 

Seriously, let's do it!

Haha.  No, that was not a VP Cheney quote; nothing that profound.   That was just me talking. 

I figure you don't always have to use them to enjoy them.  I have some I haven't shot for years but I still enjoy them.

OK, Three flights, two ground loops and finally a good landing today.  I removed the cam for the tailwheel release on the Maule tailwheel that made all the difference.

 

Herman I know you have a lot more experience with these little planes than I do but from my experience with the wheel becoming free swiveling on landing it is hard to imagine that the free swiveling tailwheel will be a good thing, this is of course coming from a newbie to the Avid/Kitfox world.

 

I did get good at repairing the fuselage and found out that some reinforcement is required.  I really like the Bush Gear that I purchased from Mark and Lowell at HighWing llc.  They are great to work with and I can recommend them highly.

What VP Cheney said.  Exactly!   I wish I still had about every gun I have owned and a lot more I would like to have.

Guess he said that too - I personally heard him say the other quote - either one earns my respect.

Never thought I would be able to say this, but I have more than I need - they are just weight to keep my safe from blowing away in a tornado - don't hunt or shoot anymore - only need two for protection.

Better to sell them and go pay for a tombstone, so I can make sure they spell my name right !!!!!

I gave each of my girls one gun, and gave my step-sons and wife's grandson one gun each, and told them I would sell the rest.

ED in MO