Specifications for Modifications

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Posted

As a new "newbie" just now trying to find a suitable aircraft and reading about all kinds of tricks and tweaks that make a big difference in handling and performance, I'm hoping that someone will lead me in the right direction as I continue to acquire a whole basketful of questions. Watch out--I may be getting oranges mixed up with apples here . . .

I want folding wings and STOL performance, meaning Avid, Kitfox, Zenith, etc. and I'm having a helluva time figuring out which way to go. Any of them seem fine to me on paper or pixel, but it seems that there is a lot more to know than I think I know now. Here are some questions:

1. Wings. Length? I'm told that I don't want speed wings for STOL work. Some people like and don't like the leading edge slats. Some say that vortex generators (VG's) will help a lot, along with slats; others say without slats. Some aircraft have flaperons with a lot of travel; others say travel is limited and they're not intended to add lift. Some say folding is a cinch with Avid/fox, but is hell with the Zenith.

1a. Glide ratios, descent rates, and dead-stick landings. Which aircraft/wings are a real problem with the engine out and with which is a steep descent rate/glide ratio an advantage in STOL operations?

2. Landing gear. Some say there is an "aftermarket" replacement gear that is wider that improves ground handling.

3. Fuselage. Some say that lengthening is a good modification (mod) . . . (?)

4. Engines. All the makes are confusing. I want the best engine I can get. Some say the 2-cycle gets you off the ground quicker than the 4's, but is it worth the downsides (what are the downsides)?

I've got more, but will stop here. Thanks for any corrections to my assumptions and answers to my questions.

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Posted

Twister welcome to the Forum! I'll do my best at answering your questions. First and foremost a lot of your questions are opinion based and not fully factual. My answers my very well differ entirely from say Larry's who will tell you that 2 strokes are deathtraps :angeldevil: J/K Larry!!

1. I haven't met anyone yet who was happy with standard length speed wings. The main difference is speed wings have a flat bottom and STOL wings are undercambered. The speed wing can be lengthened though and I hear that helps alot. If your wanting to get in and out short look for a STOL wing. I am not a huge fan of slats. A guy in Australia has a Zenith 701 that he removed the slats and added VG's with not much difference in performance. VG's and their results is a highly debateable topic on these high lift slow flying wings.

1A. Most STOL airplanes glide like a rock. An old book titled "How to fly a Kitfox" compares these airplanes to a heavy Cessna by way of a Badminton Birdie compared to a Tennis Ball. They are light and draggy like a birdie. and when the fan quits blowing you had better point the nose at the ground like NOW or you will stall. They will decellerate extremely quickly! I lost 3 good friends in the past year and ALL of them were departure engine failures followed by a stall. With that said if you manage your airspeed and glide properly you can set down at around 40-50mph. This is a very surviveable speed no matter what you hit as long as it's controlled and your wings level. I would much rather be in the welded, triagulated chromoly fuse of a Kitfox/Avid than a metal box like a Zenith anyday during a crash situation.

2. There is several options for landing gear that is 10" wider over stock. Makes ground handling a night and day difference. I had 500 landings and 250 hours on the stock gear before I switched. It's just fine but it requires your attention on pavement.

3. The main reason people stretch the fuse is accomodate heavier engines on the nose such as auto conversions or the Rotax 912.

4. If money is no option look for a Rotax 912. They are a bit heavier but a sweet little engine. Some guys have had great luck with Subaru Conversions but they can get heavy if not careful. These airplanes were originally designed very light with a two stroke motor. They evolved from there and gradually got heavier and faster with bigger engines and became more of a well performing cruiser than a true STOL airplane. If you really want to get in and out short you can't hardly beat a 550lb or less early model with a two stroke!!

The downsides that you'll hear about two strokes is fuel burn, low TBO times, and reliability. With that said I love mine and I have flown behind it over some of the most inhospitable terrain the Western US has to offer. If I had an extra 20 grand laying around I would probably go with a 912 but I don't so therefore I fly and enjoy what I have to the fullest.

Hope this helps. Feel free to ask more questions.

My 535lb two stroke powered Avid doing what it does best..

IMG_3730_zpsdefbaf9b.jpg

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Posted

Hey Joey, If I am the Larry you refer to with ref two strokes - I got a bad rap! I love my 582! I don't think that there is a better engine for our frames than the 2 stroke. What I didin't like was specifically, was the old McCaugha(sp) that was sitting around available for a good deal. One on those cost my buddy his gyro - TWICE! They may have been good 10 years ago, but anymore, I would run from them bases on his experiences of trying to get it to run right. Nothing performs as well as the 582 when consoder wt/hp/torque/$$.

larry M

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Posted

You are not the Larry that Joey was ribbing :lol: That would be another Larry here that happens to drive a KF with a 912 in the nose. We like to go back and forth over the 2 stroke deal with some good natured ribbing :snack:

To answer a few of Twisters questions.

I flew my C model HH with the undercambered wing, a KF I built very light, and my other buddies MK IV speed wing with wing extensions. The KF 1 is the winner hands down on STOL but Bob built his light and the KF has 3' more wing than my HH. The MK IV with extensions was a surprise to me as I could get it in and out just as short as I did with my HH, yet it was lighter on the controls and just felt a bit more "sporty" I really like that wing. Stalls were on par with mine (just kind of mush, not really a breaking stall unless you really forced it).

Like Joey said, when the pilot cooling fan stops, you are going to on the ground very quick. Light plane, high drag, means no real forward energy. They do glide OK with full control, you just have to know that you are not going to get very far. Add floats to that and wow.. I went from 1000' to on the water in under 30 seconds, but I did slip hard at the end to hit the pond. You should be able to get around 450-500 FPM at 65 MPH. Do the math from 100' and your not going very far from where you started especially if you have to add a few turns in there.

Joey has answered the other questions very well.

The 2 stroke versus 4 stroke debate....

If you are new to 2 strokes, there is a steep learning curve. 2 stroke MUST be flown differnetly than a 4 stroke if you want to keep it alive. There is a wealth of info out there if you want to go the 2 stroke route. If your only mission is STOL and low and slow, you just cant beat a light, basic airframe and a 2 stroke. If you are looking more towards a CC plane then the 4 stroke MAY be a better choice. They are heavier, yet burn less fuel so if you are not one of those guys that tops the tanks off even for a 30 minute flight, most of the weight gain can be negated by carrying less fuel. If someone gave me a 912 or I found a SMOKING deal on one, I would be very tempted to put it in the nose, but I wont pay new prices for one, I would go buy a Pacer instead for less money.

What is your mission 90% of the time? Do you plan on alot of solo local, dual CC, back counrty flying and camping? Just day trip fun flying? Just how big a boy are ya?? no offence, but if you are 6'5 and 320 then an early KF or avid is not the plane for you. TRying to get in and out would just be a night mare. That being said, I know of several BIG BIG ole boys that put the stick in the center and made it a very comfortable SINGLE SEAT airplane.

Welcome to the site and hit us with any questions you have, that is what we are here for!

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Posted

Thanks a BUNCH to everybody!

Here's what I think I may want after reading y'all's comments: Avid or Kitfox (I'm a little worried about the round cowl reducing visibility while taxiing) with the Bluehead 2-stroke, with wider gear and lengthened wings and fuselage. I say "Bluehead" because I've heard bad things about the "Grayhead," but straighten me out if that's horsepucky. I don't know enough about 2-strokes except that they sound awful and the two-strokes I've used on other things seem to like to quit with any power adjustments. Maybe with the lighter 2-stroke I wouldn't need the longer fuselage, but I'm thinking that it might improve directional stability. Yes, no? Not worth it? Also, I'm still a little confused about the tail wheel problem--I've flown a Citabria with a Maule tailwheel, and thought it was better than the stock one--that's why I wanted to know why it was "crappy."

I wonder about trim. Can they be trimmed out for hands-off cruise? Does one have to stand on the rudder all the time?

I'm 5'11" and 200 with ten pounds of clothes on and 36" Levis are a little tight. I've seen a Kitfox on the ground, and they look cramped for two people, but I've never sat in one. My wife is smaller, but I doubt I could get her in it once, and no doubt never again after a steep descent. I've flown a Tri-Pacer and I thought it glided like a rock, but it had too little power and too much drag to be a decent STOL--it's been a while, but I remember the climb rate as pretty anemic. The comment about losing three friends to takeoff power failures is, well, unimpressive. No, spooky! But thanks for the frankness.

I've already used the plane parachute idea on my wife, so if I have a heart attack she can just float herself and my carcass to the ground, but I suspect that would not be an option close to the rocks.

Seriously, does the longer wing improve glide ratio much, and are there any other downsides to that mod?

THANKS agin, y'all!

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Posted

You are not the Larry that Joey was ribbing :lol: That would be another Larry here that happens to drive a KF with a 912 in the nose. We like to go back and forth over the 2 stroke deal with some good natured ribbing :snack:

To answer a few of Twisters questions.

I flew my C model HH with the undercambered wing, a KF I built very light, and my other buddies MK IV speed wing with wing extensions. The KF 1 is the winner hands down on STOL but Bob built his light and the KF has 3' more wing than my HH. The MK IV with extensions was a surprise to me as I could get it in and out just as short as I did with my HH, yet it was lighter on the controls and just felt a bit more "sporty" I really like that wing. Stalls were on par with mine (just kind of mush, not really a breaking stall unless you really forced it).

Like Joey said, when the pilot cooling fan stops, you are going to on the ground very quick. Light plane, high drag, means no real forward energy. They do glide OK with full control, you just have to know that you are not going to get very far. Add floats to that and wow.. I went from 1000' to on the water in under 30 seconds, but I did slip hard at the end to hit the pond. You should be able to get around 450-500 FPM at 65 MPH. Do the math from 100' and your not going very far from where you started especially if you have to add a few turns in there.

Joey has answered the other questions very well.

The 2 stroke versus 4 stroke debate....

If you are new to 2 strokes, there is a steep learning curve. 2 stroke MUST be flown differnetly than a 4 stroke if you want to keep it alive. There is a wealth of info out there if you want to go the 2 stroke route. If your only mission is STOL and low and slow, you just cant beat a light, basic airframe and a 2 stroke. If you are looking more towards a CC plane then the 4 stroke MAY be a better choice. They are heavier, yet burn less fuel so if you are not one of those guys that tops the tanks off even for a 30 minute flight, most of the weight gain can be negated by carrying less fuel. If someone gave me a 912 or I found a SMOKING deal on one, I would be very tempted to put it in the nose, but I wont pay new prices for one, I would go buy a Pacer instead for less money.

What is your mission 90% of the time? Do you plan on alot of solo local, dual CC, back counrty flying and camping? Just day trip fun flying? Just how big a boy are ya?? no offence, but if you are 6'5 and 320 then an early KF or avid is not the plane for you. TRying to get in and out would just be a night mare. That being said, I know of several BIG BIG ole boys that put the stick in the center and made it a very comfortable SINGLE SEAT airplane.

Welcome to the site and hit us with any questions you have, that is what we are here for!

My mission is primarily operating off back-country roads (IF I can realistically trailer it and fold/unfold the wings in minutes rather than hours--also a gimpy one-man operation, with a little assistance from my wife sometimes), but I would like to fly it in and out of airports if necessary, and do some x-country in a pinch.

I'm also wondering just how much STOL performance I would be suffering with the Rotax 912 and a ground-adjustable prop?

Thanks much!

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Posted

What do ya'll think of a Mark 4 with speed wing and a Jaibru engine?

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Posted (edited)

What do ya'll think of a Mark 4 with speed wing and a Jaibru engine?

You might find ONE on here who likes the Jab engine - there have been problems with them and the prop is too small, IMO.

NOW, I WOULD BE BANNED ON ANY OTHER SITE, BUT MAY BE PUT ON THE "HIT LIST" FOR THE FOLLOWING:

I dont know where you are located, but I would like to hear that you checked out a RANS, at Hays, Kansas.

They are a neat little bird, and easy to build - and no danged flaperons - just standard wings. The seats are the most comfortable I have ever sat in - you can get tandem or side-by-side seating.

They even have an option of a "lace-on, already finished", fuselage covering, so you dont even have to paint.

IF I had not been led down this long Kitfox road, I would have been flying a RANS years ago.

ED in MO

P.S. You can get the RANS with a nose wheel too - why fight a tailwheel? (Now I know I'm in deep doo-doo!)

AND, YES, I will put a tri-gear anywhere you can put a tail-dragger - they both become 2-wheelers the second you hold brakes and open the throttle. (now that should start a ruckus!) BUT, I do wonder why I have to replace so many tail skids?

Edited by Ed In Missouri

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Posted

Thanks a BUNCH to everybody!

Here's what I think I may want after reading y'all's comments: Avid or Kitfox (I'm a little worried about the round cowl reducing visibility while taxiing) with the Bluehead 2-stroke, with wider gear and lengthened wings and fuselage. I say "Bluehead" because I've heard bad things about the "Grayhead," but straighten me out if that's horsepucky. I don't know enough about 2-strokes except that they sound awful and the two-strokes I've used on other things seem to like to quit with any power adjustments. Maybe with the lighter 2-stroke I wouldn't need the longer fuselage, but I'm thinking that it might improve directional stability. Yes, no? Not worth it? Also, I'm still a little confused about the tail wheel problem--I've flown a Citabria with a Maule tailwheel, and thought it was better than the stock one--that's why I wanted to know why it was "crappy."

I wonder about trim. Can they be trimmed out for hands-off cruise? Does one have to stand on the rudder all the time?

I'm 5'11" and 200 with ten pounds of clothes on and 36" Levis are a little tight. I've seen a Kitfox on the ground, and they look cramped for two people, but I've never sat in one. My wife is smaller, but I doubt I could get her in it once, and no doubt never again after a steep descent. I've flown a Tri-Pacer and I thought it glided like a rock, but it had too little power and too much drag to be a decent STOL--it's been a while, but I remember the climb rate as pretty anemic. The comment about losing three friends to takeoff power failures is, well, unimpressive. No, spooky! But thanks for the frankness.

I've already used the plane parachute idea on my wife, so if I have a heart attack she can just float herself and my carcass to the ground, but I suspect that would not be an option close to the rocks.

Seriously, does the longer wing improve glide ratio much, and are there any other downsides to that mod?

THANKS agin, y'all!

The grey head is the older version but it can be modified with the ceramic water pump seal and a thermostat to be very close to the Blue head.

You don't need the fuse stretch unless you are looking to put a lot weight on the nose.

The MK IV (Mark IV) had a trim tab from the factory as well as some C models. Mine does not but you can rig the flaperons for hands off flight in cruise. That's a whole another subject...putting positive incidence on them is called reflex. It will hold the nose up but your roll will become very stiff if you put too much in there.

Rudder tabs can be added just like any other airplane. I have a small one attached with 3M adhesive tape.

To clarify my friends were lost in 3 different kinds of airplanes only one of which was a Kitfox. All three though were light stol type airplanes.

ED- no need to worry about your opinions here. I fly ALOT with a Rans S-7S and he can outperform me in every aspect. He has the 912S. The big difference is with all his mods he's flying an $80,000 airplane. I'm flying a $15,000 airplane and 9 times outta 10 were landing the same strip together and cruising within 20mph of each other. I agree with you, the S-6 and S-7 are both very capable awesome airplanes. If I was to build any kit out there I would have a Highlander. Side by side and a baggage area big enough for about anything you want to haul. The deadstick takeoff guy is a personal friend of mine and I can attest that with some mods those airplanes are killer! It too was a decedent of the Avid Flyer.

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Posted (edited)

The grey head is the older version but it can be modified with the ceramic water pump seal and a thermostat to be very close to the Blue head.

You don't need the fuse stretch unless you are looking to put a lot weight on the nose.

The MK IV (Mark IV) had a trim tab from the factory as well as some C models. Mine does not but you can rig the flaperons for hands off flight in cruise. That's a whole another subject...putting positive incidence on them is called reflex. It will hold the nose up but your roll will become very stiff if you put too much in there.

Rudder tabs can be added just like any other airplane. I have a small one attached with 3M adhesive tape.

To clarify my friends were lost in 3 different kinds of airplanes only one of which was a Kitfox. All three though were light stol type airplanes.

ED- no need to worry about your opinions here. I fly ALOT with a Rans S-7S and he can outperform me in every aspect. He has the 912S. The big difference is with all his mods he's flying an $80,000 airplane. I'm flying a $15,000 airplane and 9 times outta 10 were landing the same strip together and cruising within 20mph of each other. I agree with you, the S-6 and S-7 are both very capable awesome airplanes. If I was to build any kit out there I would have a Highlander. Side by side and a baggage area big enough for about anything you want to haul. The deadstick takeoff guy is a personal friend of mine and I can attest that with some mods those airplanes are killer! It too was a decedent of the Avid Flyer.

I forgot about the Highlander - but that is out of my price range.

The last time I looked, the RANS kit was about the same price as a Kitfox. Big difference is the cost of various engines.

Appreciate a place where I am not tarred and feathered and carried out of town on a rail:

(new terminology - Banned again!)

ED in MO

P.S. I bought the manual for the Zenith 701 years ago. Those fat wings are too slow, IMO, and the sheet metal not as strong as our 4130 tubing frames, also IMO. Couple of problems with tail design too, IMO.

ED

Edited by Ed In Missouri

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ED- no need to worry about your opinions here. I fly ALOT with a Rans S-7S and he can outperform me in every aspect. He has the 912S. The big difference is with all his mods he's flying an $80,000 airplane. I'm flying a $15,000 airplane and 9 times outta 10 were landing the same strip together and cruising within 20mph of each other. I agree with you, the S-6 and S-7 are both very capable awesome airplanes. If I was to build any kit out there I would have a Highlander. Side by side and a baggage area big enough for about anything you want to haul. The deadstick takeoff guy is a personal friend of mine and I can attest that with some mods those airplanes are killer! It too was a decedent of the Avid Flyer.

Why did I imagine the Highlander being a take-off on the Piper? Looks like a s/s PA to me....ailerons & flaps.

ED in MO

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I guess I'm the labeled 2-stroke hater. That's mostly from my own ignorance of them and having the want to NOT learn them. Sorry. :hammerhead:

Now, let me put another myth to rest. Gliding.

The guys here with the Avids and early 1-3 Kitfoxes have a very high drag under-cambered wing. This wing has great (awesome?) slow speed performance. It will, however, hit the aerodynamic "wall" at 90-100 mph and no amount of horsepower will make it go faster. This drag also makes the plane behave like a bad mitten birdie. Pull the power off and the drag will quickly slow the plane.

My Kitfox(es) is a model IV. This has the "new" Riblett airfoil that Kitfox still uses today on their SS model. It is similar but different to the Avid "speedwing" airfoil. It will give up very little in the slow end of the envelope to the undercambered wing, but allows speeds of 120 mph or more without making the wing act "unhappy". My plane will cruise all day long at 125 mph on my 80 hp 912.

Part of the transition problems with this wing/plane is the fact that it is much less draggy. It is relatively hard to make this plane slow down, even power off. This makes the plane glide like crazy. Not ready to go soaring with it, but it glides much better than an Avid, short wing Piper (by far) or even a long wing or metal Piper or even a Cessna.

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The grey head is the older version but it can be modified with the ceramic water pump seal and a thermostat to be very close to the Blue head.

You don't need the fuse stretch unless you are looking to put a lot weight on the nose.

The MK IV (Mark IV) had a trim tab from the factory as well as some C models. Mine does not but you can rig the flaperons for hands off flight in cruise. That's a whole another subject...putting positive incidence on them is called reflex. It will hold the nose up but your roll will become very stiff if you put too much in there.

Rudder tabs can be added just like any other airplane. I have a small one attached with 3M adhesive tape.

To clarify my friends were lost in 3 different kinds of airplanes only one of which was a Kitfox. All three though were light stol type airplanes.

ED- no need to worry about your opinions here. I fly ALOT with a Rans S-7S and he can outperform me in every aspect. He has the 912S. The big difference is with all his mods he's flying an $80,000 airplane. I'm flying a $15,000 airplane and 9 times outta 10 were landing the same strip together and cruising within 20mph of each other. I agree with you, the S-6 and S-7 are both very capable awesome airplanes. If I was to build any kit out there I would have a Highlander. Side by side and a baggage area big enough for about anything you want to haul. The deadstick takeoff guy is a personal friend of mine and I can attest that with some mods those airplanes are killer! It too was a decedent of the Avid Flyer.

I must say that I am very sorry you lost three friends.

Did the accidents have anything in particular in common except being STOL aircraft? That is, what is causing the accidents? Does it have to do with the aircraft being too light (lacking sufficient mass to maintain forward momentum, as one respondent mentioned), the steep angle of descent, an inability to gain enough airspeed by diving to execute a flare and/or losing too much altitude in that process, or failure to quickly enough get the nose down and execute said maneuver, climbing out at a best angle of climb speed that is too close to stall speed, or what? Are these aircraft capable of quickly trading altitude for sufficient flying speed before the loss of the available altitude if one gets the stick forward fast enough and far enough?

I'm only a newbie speculating, but here arises another question: If these very light aircraft are designed to make tight turns safely, would spiraling upward at a lower angle of attack (best rate of climb or faster--fast enough to be safely fast enough in a tight turn to avoid a stall with a sufficient margin of safety?) rather than climbing more steeply (best angle of climb speed?) be an option? I'm thinking that such a procedure might keep the speed up and the aircraft closer to the field of departure until enough altitude was gained. How much altitude would be needed for recovery in each of those cases? This gets me to wondering which engines and operating procedures were involved, and whether some engines are more prone to failure (especially on takeoff) than others.

This is all making me wonder whether or not to go for the STOL light sports and be content with a performance envelope and design that would not be so prone to departure stalls (or even straight-ahead stalls with aircraft that require more altitude to recover than is available). ???

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I must say that I am very sorry you lost three friends.

Did the accidents have anything in particular in common except being STOL aircraft? That is, what is causing the accidents? Does it have to do with the aircraft being too light (lacking sufficient mass to maintain forward momentum, as one respondent mentioned), the steep angle of descent, an inability to gain enough airspeed by diving to execute a flare and/or losing too much altitude in that process, or failure to quickly enough get the nose down and execute said maneuver, climbing out at a best angle of climb speed that is too close to stall speed, or what? Are these aircraft capable of quickly trading altitude for sufficient flying speed before the loss of the available altitude if one gets the stick forward fast enough and far enough?

I'm only a newbie speculating, but here arises another question: If these very light aircraft are designed to make tight turns safely, would spiraling upward at a lower angle of attack (best rate of climb or faster--fast enough to be safely fast enough in a tight turn to avoid a stall with a sufficient margin of safety?) rather than climbing more steeply (best angle of climb speed?) be an option? I'm thinking that such a procedure might keep the speed up and the aircraft closer to the field of departure until enough altitude was gained. How much altitude would be needed for recovery in each of those cases? This gets me to wondering which engines and operating procedures were involved, and whether some engines are more prone to failure (especially on takeoff) than others.

This is all making me wonder whether or not to go for the STOL light sports and be content with a performance envelope and design that would not be so prone to departure stalls (or even straight-ahead stalls with aircraft that require more altitude to recover than is available). ???

Please note: I did NOT intentionally place that "emoticon" at the end of my comment, I put three question marks and the software added the emoticon. I NEVER use emoticons!

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I guess I'm the labeled 2-stroke hater. That's mostly from my own ignorance of them and having the want to NOT learn them. Sorry. :hammerhead:

Now, let me put another myth to rest. Gliding.

The guys here with the Avids and early 1-3 Kitfoxes have a very high drag under-cambered wing. This wing has great (awesome?) slow speed performance. It will, however, hit the aerodynamic "wall" at 90-100 mph and no amount of horsepower will make it go faster. This drag also makes the plane behave like a bad mitten birdie. Pull the power off and the drag will quickly slow the plane.

My Kitfox(es) is a model IV. This has the "new" Riblett airfoil that Kitfox still uses today on their SS model. It is similar but different to the Avid "speedwing" airfoil. It will give up very little in the slow end of the envelope to the undercambered wing, but allows speeds of 120 mph or more without making the wing act "unhappy". My plane will cruise all day long at 125 mph on my 80 hp 912.

Part of the transition problems with this wing/plane is the fact that it is much less draggy. It is relatively hard to make this plane slow down, even power off. This makes the plane glide like crazy. Not ready to go soaring with it, but it glides much better than an Avid, short wing Piper (by far) or even a long wing or metal Piper or even a Cessna.

MOST interesting! Makes me wonder if this mod might be for me--not so much that I care about the speed, but I am interested in the lower end of the operating envelope. Might I still get reasonable short field performance out of the Riblett airfoil? Would I need to lengthen the fuselage to hang the 912 on one? Is the Riblett wing interchangeable with the speedwing; if not, what changes need to be made? I'm thinking of buying a Mark 4 with a speedwing, and was thinking of changing it out for the STOL wing, but now I'm not so sure . . .

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I guess I'm the labeled 2-stroke hater. That's mostly from my own ignorance of them and having the want to NOT learn them. Sorry. :hammerhead:

Now, let me put another myth to rest. Gliding.

The guys here with the Avids and early 1-3 Kitfoxes have a very high drag under-cambered wing. This wing has great (awesome?) slow speed performance. It will, however, hit the aerodynamic "wall" at 90-100 mph and no amount of horsepower will make it go faster. This drag also makes the plane behave like a bad mitten birdie. Pull the power off and the drag will quickly slow the plane.

My Kitfox(es) is a model IV. This has the "new" Riblett airfoil that Kitfox still uses today on their SS model. It is similar but different to the Avid "speedwing" airfoil. It will give up very little in the slow end of the envelope to the undercambered wing, but allows speeds of 120 mph or more without making the wing act "unhappy". My plane will cruise all day long at 125 mph on my 80 hp 912.

Part of the transition problems with this wing/plane is the fact that it is much less draggy. It is relatively hard to make this plane slow down, even power off. This makes the plane glide like crazy. Not ready to go soaring with it, but it glides much better than an Avid, short wing Piper (by far) or even a long wing or metal Piper or even a Cessna.

Oops! I may have jumped the gun in my earlier responses to this post--newbie ignorance again? If this wing causes excessive floating, could that mess up short-field landings in the absence of something to kill lift at the right moment? This reminds me of yet another question--slipping. With a plane that glides like a rock anyway, if one wanted to clear some obstacles on approach and "hit" the threshold on or before "the numbers," does one use flaperons, slip, or both without taking out the gear or something even more precious? Really, I'm that ignorant of how these aircraft are operated . . .

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Accident reports?

Stimulated by the recent report of three losses of LSA pilots in departure accidents, I started trying to find accident reports by aircraft name. No luck yet? Any ideas?

I also looked on this site for an accident category, but didn't find one. Did I miss it or is there none?

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Posted (edited)

Accident reports?

Stimulated by the recent report of three losses of LSA pilots in departure accidents, I started trying to find accident reports by aircraft name. No luck yet? Any ideas?

I also looked on this site for an accident category, but didn't find one. Did I miss it or is there none?

Sport Aviation and Kitplanes magazines sometimes have the Federal Government reports or summaries - problem is, the government treats all "non-certified" aircraft as the same, gyrocopters, amateur built airplanes, etc., and does not divide reports by type of engine either.

The only report I have put on here, or have seen, was about a rough landing with a factory certified Luscomb.

I think there have been a couple of other mishaps, but not departure accidents.

ED in MO (now enjoying over 60 years of flying)

P.S. When you look at statistics; "The most dangerous part of flying is driving to and from the airport."

Edited by Ed In Missouri

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Posted (edited)

Sport Aviation and Kitplanes magazines sometimes have the Federal Government reports or summaries - problem is, the government treats all "non-certified" aircraft as the same, gyrocopters, amateur built airplanes, etc., and does not divide reports by type of engine either.

The only report I have put on here, or have seen, was about a rough landing with a factory certified Luscomb.

I think there have been a couple of other mishaps, but not departure accidents.

ED in MO (now enjoying over 60 years of flying)

P.S. When you look at statistics; "The most dangerous part of flying is driving to and from the airport."

Well, the old flyer just took his memory pill, which he forgot to take this morning!

I do have the remains of a Kitfox that landed in a tree on a departure scenario, which happened many years ago:

The builder put a "too-small" wire on his fuel pump and it burned out on takeoff - Could have happened with any engine.

He is still flying.

ED in MO

Edited by Ed In Missouri

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Oops! I may have jumped the gun in my earlier responses to this post--newbie ignorance again? If this wing causes excessive floating, could that mess up short-field landings in the absence of something to kill lift at the right moment? This reminds me of yet another question--slipping. With a plane that glides like a rock anyway, if one wanted to clear some obstacles on approach and "hit" the threshold on or before "the numbers," does one use flaperons, slip, or both without taking out the gear or something even more precious? Really, I'm that ignorant of how these aircraft are operated . . .

My friend (who just built the Avid/Kitfox hybrid) has his own strip at his home. His strip is 1600' long, 1500' MSL, but built on the top of a knoll, with the center 20' higher than the ends. Also there are 70' trees on the north end, 20' on the south. This scenario means that landing from the north requires some skill and technique. Landing from the south is a non-event. He flew a Vagabond for years and his technique was to fly a normal approach, clear the trees, pull power to idle and push the nose down and flare at normal height and you're done. Easy-peasy. I tried this method once in my Kitfox. I still was floating at the top of the hill so a go-around was mandatory.

My technique to land at his place, now, is all about energy management. 60 mph on down wind, 55 on base and no more than 50 on final. Full flaps, 20°, helps. I aim to put the wheels on the tree tops, which will give 10' or so of clearance. Just as I clear the trees, I kick full slip, sink to 5-10', straighten out and land. If I have done it right, I touch down at 35-40 mph and easily stop by the top of the hill.

So in answer to your question, flaps and slipping can be used together to still land short over an obstacle. But the main thing is speed and energy control on approach.

Edited by Av8r3400

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Sport Aviation and Kitplanes magazines sometimes have the Federal Government reports or summaries - problem is, the government treats all "non-certified" aircraft as the same, gyrocopters, amateur built airplanes, etc., and does not divide reports by type of engine either.

The only report I have put on here, or have seen, was about a rough landing with a factory certified Luscomb.

I think there have been a couple of other mishaps, but not departure accidents.

ED in MO (now enjoying over 60 years of flying)

P.S. When you look at statistics; "The most dangerous part of flying is driving to and from the airport."

Thanks, Ed. I've been flying since '62, but not that many hours and have been on the ground for close to fifteen years now. I flew quite a variety of aircraft, from champs to T-34's, but I liked the Citabria the best. The fact that you've survived all those years says a lot about the value of your ideas and advice. I'm 74, and with the exception of a few ailments and broken pieces, just as eager to fly as I was in '62. I will have to fly sport rules if I manage to get a good bird cheap enough, and my wife thinks I'm crazy (she's usually right), but if I can clear those obstacles, I may yet get into the air again, largely thanks to you and your amis on this great site!

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My friend (who just built the Avid/Kitfox hybrid) has his own strip at his home. His strip is 1600' long, 1500' MSL, but built on the top of a knoll, with the center 20' higher than the ends. Also there are 70' trees on the north end, 20' on the south. This scenario means that landing from the north requires some skill and technique. Landing from the south is a non-event. He flew a Vagabond for years and his technique was to fly a normal approach, clear the trees, pull power to idle and push the nose down and flare at normal height and you're done. Easy-peasy. I tried this method once in my Kitfox. I still was floating at the top of the hill so a go-around was mandatory.

My technique to land at his place, now, is all about energy management. 60 mph on down wind, 55 on base and no more than 50 on final. Full flaps, 20°, helps. I aim to put the wheels on the tree tops, which will give 10' or so of clearance. Just as I clear the trees, I kick full slip, sink to 5-10', straighten out and land. If I have done it right, I touch down at 35-40 mph and easily stop by the top of the hill.

So in answer to your question, flaps and slipping can be used together to still land short over an obstacle. But the main thing is speed and energy control on approach.

Thanks Av8r, I've got a lot to learn, and if I ever get off the ground again, this kind of information will be a big help in getting me trained up.

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Well, the old flyer just took his memory pill, which he forgot to take this morning!

I do have the remains of a Kitfox that landed in a tree on a departure scenario, which happened many years ago:

The builder put a "too-small" wire on his fuel pump and it burned out on takeoff - Could have happened with any engine.

He is still flying.

ED in MO

Waal, I can't even spel electrishun, so I sympathize with him. Luckily, I have y'all and an 82-year-old buddy who is an A&P to be my guardian angels.

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My friend (who just built the Avid/Kitfox hybrid) has his own strip at his home. His strip is 1600' long, 1500' MSL, but built on the top of a knoll, with the center 20' higher than the ends. Also there are 70' trees on the north end, 20' on the south. This scenario means that landing from the north requires some skill and technique. Landing from the south is a non-event. He flew a Vagabond for years and his technique was to fly a normal approach, clear the trees, pull power to idle and push the nose down and flare at normal height and you're done. Easy-peasy. I tried this method once in my Kitfox. I still was floating at the top of the hill so a go-around was mandatory.

My technique to land at his place, now, is all about energy management. 60 mph on down wind, 55 on base and no more than 50 on final. Full flaps, 20°, helps. I aim to put the wheels on the tree tops, which will give 10' or so of clearance. Just as I clear the trees, I kick full slip, sink to 5-10', straighten out and land. If I have done it right, I touch down at 35-40 mph and easily stop by the top of the hill.

So in answer to your question, flaps and slipping can be used together to still land short over an obstacle. But the main thing is speed and energy control on approach.

Av8r, what wings do your Mark 4's have on them? Have you described them anywhere? Do you have stock gear or wide gear? When you use flaps (flaperons?), are there any special cautions to follow when slipping with 20°? I've heard stories, but don't know the level of competence of the authors. If you lost an engine or power on approach, what procedures would you follow?

Thanks again!

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Av8r, what wings do your Mark 4's have on them? Have you described them anywhere? Do you have stock gear or wide gear? When you use flaps (flaperons?), are there any special cautions to follow when slipping with 20°? I've heard stories, but don't know the level of competence of the authors. If you lost an engine or power on approach, what procedures would you follow?

Thanks again!

My Kitfox (and my friend's hybrid) have the latest Kitfox wing airfoil. It is a laminar flow Ribblett design, starting with the Model IV Kitfox and continuing today through the latest SS model VII.

My plane has the Grove spring gear, which is wider than stock but no taller.

The more flap you put in the less "up" elevator authority you have. With my plane's rigging, full flap is 26° and to land with that I need to have the elevator against the stop (all the way back) in order to keep the nose up to land. It doesn't really flair in that configuration. It will settle down to the ground at about 30 mph. I do not have any issue with inversion (flapperon stall causing roll control reversal) at this setting.

I usually land power off so I would not do much differently with a power loss situation.

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