Eagler's Nest

Engines => 4 Cylinder => Certified based => Topic started by: rfeenstra on September 03, 2014, 06:29:01 PM

Title: It Flys!!
Post by: rfeenstra on September 03, 2014, 06:29:01 PM: I got my airworthiness certificate this AM, loaded my Cabin DE sideways on a trailer and hauled it to a local field. Flew for about an hour this evening. I need a different prop for my A65, left wing is just a tiny bit heavy. needs a little Rt. rudder trim, and need to move the CG back (I'm at 26% of cord, need to get closer to 30%.) Great fun! The airplane is heavy on the ailerons but turns great with a little extra rudder. Landed with extra speed and a bit of engine but was still surprised at the lack of authority for flare. I even have 2 degrees of up incidence built into the stab. Need to get the CG back a bit. I'll do some tweaking and will have a great time!

Rob
Title: Re: It Flys!!
Post by: Steve on September 03, 2014, 06:58:34 PM: Quote from: rfeenstra on September 03, 2014, 06:29:01 PM
I got my airworthiness certificate this AM, loaded my Cabin DE sideways on a trailer and hauled it to a local field. Flew for about an hour this evening. I need a different prop for my A65, left wing is just a tiny bit heavy. needs a little Rt. rudder trim, and need to move the CG back (I'm at 26% of cord, need to get closer to 30%.) Great fun! The airplane is heavy on the ailerons but turns great with a little extra rudder. Landed with extra speed and a bit of engine but was still surprised at the lack of authority for flare. I even have 2 degrees of up incidence built into the stab. Need to get the CG back a bit. I'll do some tweaking and will have a great time!

Rob

Congrats, Rob - we are waiting for the VID's with that A-65 barking!...
Title: Re: It Flys!!
Post by: rfeenstra on September 03, 2014, 07:59:15 PM: Vids?? I'll have to work on that!
Title: Re: It Flys!!
Post by: Steve on September 03, 2014, 08:22:38 PM: I sure do like running the slideshow on your gallery photos - it is a v e r y nice build...
Title: Re: It Flys!!
Post by: rfeenstra on September 03, 2014, 08:29:49 PM: I was pretty proud today. The DAR said it was the best built Eagle he's licensed and he's inspected several. Didn't fine anything to complain about. I had a hard time getting my head in the cabin! I haven't checked the vid on the first takeoff yet, but it was into the sun, so it probably didn't turn out. Sun was low and bright!
Title: Re: It Flys!!
Post by: Tom H on September 04, 2014, 07:56:07 AM: Rob, congrats on the flying DE. Some real fun starts now.

You are on the right track to get the flying CG more towards 28-30 percent of wing cord. We went through the same thing with DE Stubby, finally shortening the front of the fuselage to move the engine back, and still ended up putting the battery in the tail. We are probably around 28 - 29 percent, and it flies/lands real good, but will not break into a stall. We think even a bit more aft CG may be worth trying.

Our DE is also a bit left wing heavy. I think mostly because the body inside is on the left side. I can lean to the middle and cause the plane to bank right. I rigged up a bungee to offset the heavy left wing, and it flies level with no arm strain, now.

The ailerons are generally heavy, especially in rougher air.

We also had to put on a rudder trim tab bent out to the right; it biases in left rudder. Could be that the two "fixes" are fighting each other, but it flies well.

The elevator trim is real sensitive at higher speeds. Just a touch on the lever makes a difference. Less effective at slow speeds, but it does reduce up elevator stick force during landing. It got a lot more effective after we discovered that the control horn on the trim tab was loose, resulting in not moving the tab much at all, and tightened it. Seems that all the eyeballs that inspected the plane missed the fact that the nuts connecting the control horn to the tab were not elastic stop nuts, but plain nuts, and they loosened up.

We set the horiz stab as much nose-down as possible, a bit more may help us, but it will be involved to make that happen. OK for now.

Keep the reports coming. Seems there are a lot of LEXL reports, but not too many DE reports, especially after Gil gave his up, Utt cashed in and Shane has disappeared.
Title: Re: It Flys!!
Post by: rfeenstra on September 04, 2014, 05:06:07 PM: Thanks! When I built the DE, I knew you had shortened the nose to help with getting the CG back. I built mine that way from the start. I think I brought the firewall back 5", as i recall. The A65 mags need some room so my engine mount is a bit more forward. I believe I wound up with the prop a good 3" back from the plans location. I wish it could have been more. It's easy to build a new, longer engine mount if the CG wound up too far back. But, alas. I need to add lead to the tail.

Today I added an 8 lb weight to the tail spring bringing the CG back about an inch. I believe I am now at about 27% of cord. It really seems to have helped so I think I will add a gel cell battery for radios back there as well. Might as well make the weight useful.

Knowing that a lot of people had flare problems and shimmed their stab, I built in 2 degrees of UP incidence hoping that would help in the flare. Don't have anything to compare it to so I don't know. I also put in 2 degrees of DOWN thrust in the engine mount as I used to do in flat bottom winged RC models. When you pull throttle, it should allow the nose to come up easier. Don't know if it helped or hindered!

I had to put a rudder trim tab on my champ several years ago and I may do that on here. I'll experiment with shifting weight side to side to see how it affects the heavy wing. Given the "heaviness" of the ailerons, a little right aileron to compensate for pilot weight may seem heavy. If I decide I need to change the incidence of a wing, all I have to do is make a new aluminum block for the rear strut. It probably would be nice to have an adjustable rear strut from the start.

Interestingly, the DAR who inspected my plane has inspected several eagles. He said that some have added a bungee or spring to the elevator to help take some of the weight of the elevator. I've never read anything about that on the forum. Have you?

Had fun flying it today but my first landing on pavement with a cross wind was an ABORTION! I'll work on it.

Rob
Title: Re: It Flys!!
Post by: Tom H on September 05, 2014, 07:06:33 AM: Rob, sounds like you are re-playing a lot of what we did with Stubby to get the flying CG right. I wrote the equivalent of a book on our findings, efforts and fixes in the old Yahoo forum, probably still available if searched for.

No bungee needed on the elevator. I often lift the tail soon after power-up at takeoff and don't notice any major force on the stick. During the climb the elevator trim tab can be adjusted to hold the climb with minimal force on the stick. Then, re-adjusted after leveling out for cruise. During approach for landing, the tab can be adjusted for almost neutral force on the stick. By the way, our elevator trim tab is per plans, but the activation control is by Bowden cable. Seemed simpler to build to us, probably little or no weight penalty.

Pavement. That's another story. We operate from a grass strip, and landing there is easy, even with cross winds. I've landed on pavement only a few times, and it is a different animal. Have to work quickly to keep control. Almost lost it once during a spot landing contest when I tried to stretch the final to touchdown with lively crosswinds. It was a wild ride from the inside, but the video makes it look tame. I did not win the contest, not even close.
Title: Re: It Flys!!
Post by: Sam Buchanan on September 05, 2014, 08:05:24 AM: Quote from: Tom H on September 05, 2014, 07:06:33 AM
Pavement. That's another story. We operate from a grass strip, and landing there is easy, even with cross winds. I've landed on pavement only a few times, and it is a different animal. Have to work quickly to keep control.
I suspect that is common with all the Eagles, certainly is with a particulate XL I know about. Stay on top of it and it'll go straight...get a bit lazy and it'll take you on a tour of the runway... ;)
Title: Re: It Flys!!
Post by: rfeenstra on September 05, 2014, 03:03:48 PM: It sure did! The Champ I had had balloon tires on it that always lost air over a weeks time. I normally let them squat quite a bit. Once, I pumped them up a bit so that I wouldn't have to fill quite so often. Next time I landed on pavement, I almost lost it. Let the air back out and it was a @#$% cat. I have the tires on my DE soft, but they are from my Comanche so they have fairly stiff sidewalls. I would like to find some different tires for it. The Comanche tires were FREE.

I made several takeoffs on pavement today, but always landed on grass. FUN!!!! Getting a feel for it, though I want to move the CG farther back. I want to get it back to 30% (at about 28% now).
Title: Re: It Flys!!
Post by: rfeenstra on September 05, 2014, 08:54:50 PM: Interesting! The forum bleeped out a common term for a gentle cat (sometimes also refers to body part!)

I have uploaded a few pics of the first flight. Pictures were taken directly into the sun, so they don't show up very good. I have a couple of video clips taken with a point and shoot camera that I'll try to edit and post. I've never done that so give me some time.

Rob
Title: Re: It Flys!!
Post by: rockiedog2 on September 06, 2014, 05:06:07 AM: if you wanta cuss just eliminate the space before the cuss word and the filter will miss it. watch this...rat's ass. now...rat'sass. when it posts the first ass will be scrambled. i think. we'll see...
Title: Re: It Flys!!
Post by: rockiedog2 on September 06, 2014, 05:08:16 AM: see. the filter changed it to arse.
now how silly is that?
management came up with all that. they're probably gonna put me on moderation now.
Title: Re: It Flys!!
Post by: Dan_ on September 06, 2014, 05:46:51 AM: Quote
Interesting! The forum bleeped out a common term for a gentle _ _ _. (sometimes also refers to body part!)

Rob,

You refer to the gentle (usually) animal --the word for which can never be uttered here. The pathology relates to animal cruelty a few on here find humor in. It is a hold over from the old yahoo group.

Puddy tat would be a good substitute in your sentence, and is the glaring exception to the list of "cuss words" that are blocked here by the forum software, most of which no one would even consider using in mixed company, let alone something as public as a forum.

It is what it is. (rather ridiculous in the case of how to refer to Sylvester, but the few who like the drama refuse to let it go)

The list is an adaptable, ongoing work in progress. It does not have to be grounds for a grievance, or infringe on freedom of expression.

A little creativity when you want to use strong language is all it takes.
Title: Re: It Flys!!
Post by: rfeenstra on September 06, 2014, 06:18:05 AM: I understand! It's hard for software to account for context. Anyway, more flights today with the CG farther back. Shooting for 30% cord.

Rob
Title: Re: It Flys!!
Post by: rockiedog2 on September 06, 2014, 10:04:55 AM: >>>N end of S bound rodent.

Doolin you changed my post didn't you. figures.

i've seen you say s*** on the list. now what kinda example is that?
Title: Re: It Flys!!
Post by: Dan_ on September 06, 2014, 10:25:21 AM: Dint change your post... I added a couple of entries to the filter to catch the deleted space work around...

Perhaps it is time to turn the dirty word filter off.

I don't get why this is such a big deal..?
Title: Re: It Flys!!
Post by: riorex2002 on September 06, 2014, 01:10:56 PM: Joe
If you would just turn that darn rodent 180 he'd have the sun shining out his #@$#.see we don't need no #@$# filter.
Rex
Title: Re: It Flys!!
Post by: Dan_ on September 06, 2014, 02:08:29 PM: Joe is just stirring the s_it pot to see what jumps out. Must be raining in Grenada, he is a little bored...
Title: Re: It Flys!!
Post by: rfeenstra on September 06, 2014, 06:20:15 PM: " Rob, sounds like you are re-playing a lot of what we did with Stubby to get the flying CG right."

Doesn't everyone go through some playing to get it flying right? I added 4.5 lbs. more lead to the tail. That put the Cg at about 30% of cord. It's really starting to fly nice. The trim tab is much more effective, and I can flare to where I drop it in - NOT GOOD! Need landing practice. The sight picture is soooo different than what I'm used to. Practice, practice, practice!

Once I get it to where I like how it handles I'll have to figure out how to get rid of the tail weight and keep the CG in the 30-33% range. Steve put me on to an electronic ignition system that would get rid of the mags; there's 16 lbs off the nose. That would give me room to move the engine back a good 2", maybe 3. Then with a battery for the ignition in the tail, I'd be there. I'd have to add a wind turbine for power. All together, I think my empty weight would go down.

Having GREAT fun!

Rob
Title: Re: It Flys!!
Post by: Tom H on September 07, 2014, 07:23:22 AM: Rob, you have a nice looking Eagle, there. Used latex paint, too, kept cost down.

It's a good feeling when you make changes that go in the right direction, like sneaking up on the correct flying CG. Starts to land like a real airplane should.

I noticed on the pictures that you made the gear legs straight down, not canted forward. And, on another forum, you put out all your weights, arms, balances, etc., and said your tail wheel weight was something like 15 lbs. Ours is 34 lbs., with the canted gear. That's with the airplane sitting level, so, on the ground, the tail weight is even higher, and picking the tail up for ground handling is a load.

I've believe that the canted gear is not needed once the correct configuration is achieved to produce a flying CG at around 30%. You are right at that point with the flying CG. Do you notice any tendency to nose over with the straight gear when you taxi, brake, etc?

I'm bringing this up to allow any new builders to have some actual operational data when they choose either straight or canted gear.
Title: Re: It Flys!!
Post by: rfeenstra on September 07, 2014, 04:11:28 PM: I've never felt a tendency to nose over, though I really only use the brakes on runup with full up elevator and to make a sharp turn. As I get more used to the plane I will start playing with picking the tail up off the ground while holding the brakes to get a feel for what it will do. I really don;t think it will be a problem. I can tell that the tail doesn't come up on takeoff nearly as quickly as it did on its maiden voyage. Today I did try just once to use a lot of forward stick pinning it on the ground during one takeoff. I felt nothing unusual.

May tail weight level was about 18 lbs. Now I've added another 12. I'm glad I didn't build the canted gear!

Did a lot of landings today trying to get a feel for how best to land it. I still need to land with power. It just does not feel like I can get the nose up without some throttle. Seems about 1000 rpm works. I practiced some idle approaches today. Steve K. is right - you gotta point the nose down! To maintain a 40 mph approach, the windshield is almost all ground, not much horizon! It's amazing how draggy these things are. Our cabin versions probably more so. I'm used to the Comanche which has a great glide angle. Even the Champ had a much shallower approach. It's just something to get used to. It's actually kind of fun!

I'm not the worlds most coordinated pilot so it's for to finesse this thing on the ground, but I'll get there. Having a ball! Put about 3 more hours on it this afternoon with at least a dozen landings.

Rob
Title: Re: It Flys!!
Post by: Tom H on September 08, 2014, 05:40:22 AM: Well, with your adjustments to get flying CG correct, your tail wheel weight is getting close to Stubby's. So, even with the non-canted gear legs you should have plenty of weight on the tail wheel to resist nose-over on the ground. But, the non-canted gear does reduce the weight on the tail wheel a little bit, as compared to a canted set-up, so a little less to lift by hand. Keep us apprised of the situation.

The approach to landing in Stubby is relatively steep, especially with power at idle, as compared to other airplanes I've flown. The proper CG allows the plane to flare with no or little rpm. But, holding the steep approach until the last moment, then flaring, seems to take some practice. But, it can be done.

I was up with a friend in his 172 a while back and he let me make some landings. I had a hard time getting used to the shallow approach and keeping the speed correct. The DE has little tendency to gain speed. As you said, you have to point it at the ground, compared to larger airplanes.

By the way, Stubby is not one of the cabin versions. It's occupant area is per plans, but I added doors. So, if anything, I think I have reduced drag by a bit.
Title: Re: It Flys!!
Post by: rfeenstra on September 08, 2014, 05:46:02 AM: For some reason, I was thinking that it was a cabin version! Probably the doors that threw me off. Sorry about that. If I get used to the steep approach, I may have hard time with the Comanche!
Title: Re: It Flys!!
Post by: Sam Buchanan on September 08, 2014, 06:05:38 AM: Quote from: rfeenstra on September 08, 2014, 05:46:02 AM
For some reason, I was thinking that it was a cabin version! Probably the doors that threw me off. Sorry about that. If I get used to the steep approach, I may have hard time with the Comanche!
Or...just carry some power and you can make the approach as shallow (Comanche-ish) as you wish.
Title: Re: It Flys!!
Post by: rfeenstra on September 08, 2014, 07:15:07 AM: It's kind of fun to point the nose at the ground. I feel like a dive bomber! (Not really that drastic.) But yes, carrying a little power makes for a very conventional approach. Nice morning here, I need to go flying!

Rob