Bringing a Kitfox 1 back to life

213 posts in this topic

Posted


And if I'm not mistaken you can legally take lessons in your own plane with dual set up.

Yes of course you can.  You can do it without having dual brakes as well but it is not the smartest thing to do.

 

Share this post


Link to post
Share on other sites

Posted

That is exactly the reason I bought it, and it is finally working out for me. I actually got to fly it for myself, today (with the instructor). It was as great as I hoped it would be. Took a bit longer than I planned, but I should be able to get my license before fishing season. I work year round, but summers are especially busy. The plane was great. Beautiful day. Warmed up to the 20s, clear and calm. Last time we flew, I was sitting right seat, hands off, ducking around that cross bar. There was also a strong crosswind, that day. 

2 people like this

Share this post


Link to post
Share on other sites

Posted

I did the dual brake upgrade, not cheap. Then my jet pilot CFI drove us off the runway thru a ditch into the weeds coming in too hot. Caught his big ass boot on a tube, never said a word. I stomped so hard and saved the loop but it cost me a bent Grove spring gear too... 

Share this post


Link to post
Share on other sites

Posted

I noticed that the tubing is kind of in the copilot's way, especially the pull-starter tube by his left rudder pedal. I don't have any big issues from the left seat, but I noticed right away that there was less room on the right side, and mentioned it to my instructor. My foot got jammed in there in the first minute of testing, with ordinary shoes. Need to keep that left foot toward the right side of the pedal. The copilot also has to deal with the crossbar that angles across the cockpit, right where the top of his head should be. 

Share this post


Link to post
Share on other sites

Posted

Same in the Avid. I cut that pull start handle/rope guide off my Mk-IV for right side brake pedal clearance.

image.jpeg

image.jpeg

Share this post


Link to post
Share on other sites

Posted

Had some good company next door, today. Nice 801.

579B79F6-51E3-4D7B-B64F-98F75B6EA74B.jpeg

Share this post


Link to post
Share on other sites

Posted

Old #29 has been good to me. I have about 75 hours on the Hobbs, since getting her back in the air. It was time to reset the point gap, since timing was nearing the lower end of the range. Since I had it in the shop, with the engine off, I decided to install the wing tanks, replace the windshield, and lengthen the tail feathers. Horizontal stabilizer got angled down as much I could. Four inches added to the chord of the rudder and elevator. I made some flapperon end caps to fix up the inside ends, which were torn up a little from folding the wings, and were slightly loose. They are very solid now. 

6CD8FB73-3579-4314-8E78-958557A56158.jpeg

9F60B320-D632-4595-9A49-39F48B89B67C.jpeg

E53F251D-722C-43C3-881F-DEE6DA5B124E.jpeg

52CC8AC3-2723-4CEA-A8F8-4C029E8AA549.jpeg

3B95129D-76C3-475E-A8B8-BEEC68D2AF34.jpeg

1B9802F3-01E4-44D3-8FEF-43200956D57A.jpeg

05A8C5A0-F5A0-490C-8617-EA859A313586.jpeg

B437665A-E5E2-44A7-81BE-176D8F89DD12.jpeg

CD679A40-A4E0-4DF3-B43B-CF781979B7A5.jpeg

03B7430D-3626-43CE-A20B-B47AF6BDAD59.jpeg

C0461E43-01EF-438F-AC59-365E14CFDA91.jpeg

B804119D-6332-4A62-A3AC-674E3C8326FA.jpeg

1ECE680E-E8FD-44C0-BE91-1C5E00ADC7A8.jpeg

1 person likes this

Share this post


Link to post
Share on other sites

Posted


she will be even better to you after all those mods. Maybe a bit heavier ha but thats ok.

Share this post


Link to post
Share on other sites

Posted

Yes, the wing tanks added 27 pounds, but I can live with that. It's closer to 25, considering the parts I removed from the wings to fit the tanks. That's the same weight difference between the 25" tires and the 8.00s. I'm putting the small ones back on, so it will be the same weight as when I last flew it. Until I top off the tanks, anyway. But that extra six hours, or more, added to the range, will be very nice. My next project will be to put it on the skis. But first, finish this and get flying again. 

Share this post


Link to post
Share on other sites

Posted

After I did most of my flight training in the Kitfox, it was good to hear that the DPE was willing to do the check ride in it. He came close to calling it off when we had communication issues, but he toughed it out and I walked away with my PPL. My instructor and I have had a finger of an insulated leather glove stuck over our mics since February, and I didn’t remember to suggest that to the examiner on the big day, which meant his mic was picking up a lot of noise. A LOT of noise. I had to back off the throttle significantly to be able to hear him clearly. All’s well that ends well. He did say it wasn’t the best choice for a check ride, but it was a pretty good ride, all things considered. It’s been a long-time ambition of mine to get my license. Onward and upward. 

66B11522-7B08-4124-BB6D-853A2DAEF72A.jpeg

4 people like this

Share this post


Link to post
Share on other sites

Posted

I finally got my Federal 1500 skis rigged. It has been incredible ski flying around here, lately. 

592263AA-EE66-420F-8E92-5C925F8C761D.jpeg

9909F6B2-AD99-4E08-B1FE-6AFDBD83B9D4.jpeg

255407F4-2498-4F12-970D-5E22BDB0DF75.jpeg

C9873C81-9DB9-45A5-9640-806A59E72830.jpeg

81CD93DB-ED13-495A-9BC7-15DAFEB8C88E.jpeg

2 people like this

Share this post


Link to post
Share on other sites

Posted

Pretty nice.  I love ski flying as well.  Flew on wheels last evening for the first time since December something....  The last two pictures must have been on your trip to the south pole??:lmao:  JImChuk

1 person likes this

Share this post


Link to post
Share on other sites

Posted

Will this rain ever stop?
I flew for a couple hours this morning. It sure was nice. I should have taken pictures, but I kept the doors closed and just enjoyed the flight. I have a flight review due soon, so I went through a bunch of stalls, S turns, slow flight, and other maneuvers, maintaining steady altitude. The flight was followed with the hard slip and soft three point that my short field requires. The field has some bumps, so the landing isn’t always as soft as it was today. It’s always really satisfying to grease it in there like that. 91299FC2-D525-45D6-814E-EE366DC7E428.thuLast winter, I made some adjustment to my flaps. I had found that the plane would fly level, without stick pressure, with the flap lever pulled up about an inch. Typical thing that many Kitfox owners do to trim the plane’s pitch. I figured that was just wasting a few degrees of flap, and adjusted it to fly level with the flaps up all the way. That is, with the lever down as far as it will go, the plane is trimmed in flight. As a side note, I had first needed to adjust the angle of the horizontal stabilizer in order to be able to trim it and not need forward stick pressure. With the flap adjustment, I got it close, but need just a hair of back pressure now. 
I’ve been debating whether to make that last bit of adjustment by moving the flaps back up slightly, decreasing the total down angle with full flaps, or by moving the front of the horizontal stabilizer back down. I did see a slightly lower stall speed after the flap adjustment. 
After my morning flight, I decided to check the flap angle, along with the angles of the wings and horizontal stabilizer. With the plane sitting on 25” mains, on the relatively flat ground, I used the handy level feature of my iPhone to check the angles. I used a straightedge from leading edge to trailing edge of the wings, checking the angle at root and tip, as well as measuring the angle of the flat-bottomed flaperons while “flaps” were down, then up, and also checked the angle of the horizontal stabilizer, and the floor, which is used to determine level for weight and balance. CA0F8585-6BC2-4B9C-B75F-3D0A6FA21C80.thu
With the flaps down, and both flaperons at the same angle, flaps were at 26°. Note that 26° is not the flap angle, in regard to wings or angle of incidence, as the plane had all three wheels on the ground. 
9A144468-3317-469A-8F2C-CE7CE91933CE.thuWith flaps up, both sides showed 9°. This is a difference of 17°. Full flaps = 17°. I wonder how much less flap angle there was before my last adjustment. Maybe 2°-3°? 20% less?

2A0FA41D-69E2-4544-B937-4A5866010F54.thu
Full flaperon deflection netted a range of 8° to 50°, with the flaps down. That’s 42° total up to down on flaperons. That 8° is only 1° more than the wingtips, or 6° up at the root. I hadn’t considered previously, that the flaperons move up relatively less at the wingtip, due to wing twist. It has 18° up, and 24° down. It should be the other way around. Everything about it is in favor of adverse yaw.

DFA4BBD9-BFD1-4A07-BDB8-63CA9E71B109.thuThe wingtips showed the same 9° as the flaperons, flapped up. Both wings had the same angles for root and tip. The angle at the last rib was the same as the droop tip.

04290DE5-FFC2-4CA5-B457-9C5284E94A3C.thu
Wing roots showed 14°. That’s 5° of twist, root to tip. The floor was the same angle, 14°.

60CCFFDD-38A3-4004-8973-EA8DC05ACEEF.thuThe horizontal stabilizer was at 11°.

While I concluded several things from this, I’d love to hear any input you might have. 

First, let’s put in perspective. Obviously, it won’t fly a steady altitude with the floor level. The root would have zero AOA, and wingtips would be minus 5°. Flaperons would likewise be reflexed to -5°, while the horizontal stabilizer would be at -3°. I’ve often thought it could use a bit more angle of incidence. But, the floor is just a reference, anyway. A flat plane, if you will, that’s easy to level.

Ignoring all that, I think I ought to give it another 1° to 3° of flap, and put the horizontal back to its original position. Doing that would put the flaps, while retracted, at approximately the same angle as the bottom of the wing, while also increasing the total angle of the flaps, extended. That would be the same angle as the middle of the wing, rather than the tip.

I believe that this would make it more efficient inflight, as the flaperons, wings, horizontal, and elevator would not be fighting each other as much.

My wife shoots video of most of my takeoffs and landings, here at the house. Today’s video of the landing showed that the tailwheel stayed off the ground while I had the stick back a good bit. I don’t believe that I was hard on the brakes, if at all. My usual routine is to keep the tail up, after I touch down, so the tailwheel isn’t eating the bumps, and let it roll out. Balance would have been neutral or slightly aft, with just a few gallons in the panel tank, and wing tanks empty. 
https://youtu.be/p_64N6ywJDo

On the negative side, it would have about zero up aileron, at least at the wingtip, with flaps deflected. I’m not sure if it could have much more adverse yaw than it currently does, but the rudder works just fine. One more thing, that might become an issue, if it’s not already, is that the flaps might not fold up flat enough when the wings are folded back. I had considered that that was the reason for that geometry, in the first place. If I ever need another project, I could convert to differential control, but I’m not planning to do that, at this point in time. I like the ease of folding the wings back, without disconnecting anything, even if I hardly do it anymore  

I wouldn’t think there’s any benefit to taking the flaps back up. The ailerons don’t go up any further, at least, not if it’s trimmed to fly without stick pressure. I don’t have a stopper for the flap lever. It stops against the torque tube for the sticks. I’ve read the old concerns about control reversal and the need to limit flap travel, but never experienced anything like it, with about 275 hours and lots of full flap landings. Maybe that was first flight nervousness by those unfamiliar with the amount of adverse yaw, and they mistook the effect. 

Here are the stats, simplified, as with the floor leveled:

Angle of incidence, wings, average: -2.5°

Range of motion, flaps: 17°

Range of motion, ailerons: -18°/+24°; 42° total

Angle of incidence, stabilizer: -3°

Is it ever going to stop raining? Look what it’s done to me. I hope you’re all enjoying your Kitfox, whether working on it, flying it, or just considering its different angles.
 

Matt

8B6E128B-DD20-411F-B50F-0C7C2532924F.png

B62AB8F3-FCC5-48E3-B1B5-E5C9D7C2C690.jpeg

1 person likes this

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now