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Wing Extensions for squared wing tips.

skywagon8a

skywagon8a

MEMBER
SE Mass MA6

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aktango58 said:
Extend the aileron to the wingtip. Otherwise you lose lots of roll rate.
Click to expand...
That's what they say George, I did not find it to be true. I did try to find a difference and could not. The ailerons on this Cub end at what would be the tip of an original rounded Cub wing. Each wing is two feet longer than a stock Cub.
 
skywagon8a said:
That's what they say George, I did not find it to be true. I did try to find a difference and could not. The ailerons on this Cub end at what would be the tip of an original rounded Cub wing. Each wing is two feet longer than a stock Cub.
Click to expand...

That is two feet more resistance.

Under normal use, you won't see a difference, but when you are getting buffeted by gusts trying to keep her level and in the air at minimal speed in the mountains you might find it different.

I have had the stick hard over on occasion hoping they right themselves. Maybe I am a little biased!
 
MT12 said:
the spar splice seems a bit 'light' compared to Piper's Service Memo on spar splicing. PIP_SM003A. View attachment 50664
Click to expand...
There are no splices. The new spar ends just slide into the spar extrusions with a snug slip fit. There is just one 1/4" bolt in each to keep them from sliding out. Then 18 10-32 screws holding the skin to the tip rib with another 18 holding the tip to the extension. There is more than enough strength for the application. The entire extension is easily removed.
 
aktango58 said:
That is two feet more resistance.

Under normal use, you won't see a difference, but when you are getting buffeted by gusts trying to keep her level and in the air at minimal speed in the mountains you might find it different.

I have had the stick hard over on occasion hoping they right themselves. Maybe I am a little biased!
Click to expand...
I really tried to find the issue which you bring up as I had heard discussions on the topic. At minimum speed I "slammed" the ailerons stop to stop and back again. The wing followed as it should. Perhaps without the floats it would bounce around more making the ailerons less effective?? If so, I'll never know as the floats don't come off.

This is the reason I installed a fence just outboard of the left aileron to see if I could find a difference. I couldn't.
 
In the end did the horner-style wing tips help? I might have missed comments in the other thread.

Gary
 
Gary,
I am going to say NO. There was no difference between the squared no tip and the horner tip. The advantage which appears due to the horner tip seems to be strictly the increase in wing area.
 
2’ extensions Slowed my roll rate some what. Got it and more by adding 22”X6” spoiler boards. Good role control in windy conditions down to 35 mile an hour approach. Could not have done that without them

0EDDE112-767B-420F-AA2B-E624404CBA04.jpg2’ extensions
 

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I had thought of installing some simple spoilers. Since there was so little noticeable difference with the increased span, I decided it was a waste of time. Roll response on this plane has always been good, with a nice light positive response to the stick motion. Ball bearing pulleys, heim bearing hinges on the ailerons and tight cables.
 
aktango58 said:
Extend the aileron to the wingtip. Otherwise you lose lots of roll rate.
Click to expand...
To clarify, the wings on this Cub already were each 1 foot longer than a stock round wing tip Cub. The 1 foot was in the fiberglass wing tip. The new extensions are only adding 1 more foot to each wing. This adds up to a total of 4 feet more span than a stock Cub.

The ailerons already were extended outboard to the squared tip of the original Cub wing. Also the inboard end of the ailerons was shortened to allow the flaps to be lengthened. The flaps are 110" long.

These spar ends are what you would see on an original spar blank prior to cutting out the web and squeezing the two caps together to form the original pointed tip.

attachment.php
attachment.php
 
The acro community has learned long ago that most of the roll rate, or a lot of it comes from the aileron located as far out to the tip as you can get it. The reason some run the ailerons all the way up to the root of the wing, is to get it in the prop wash to help at slow speeds and high Alpha to get it in the prop wash at high power settings. Obviously the inboard ailerons close to the root will do little to help in slow speed approaches on short final.
 
skywagon8a said:
That's what they say George, I did not find it to be true. I did try to find a difference and could not. The ailerons on this Cub end at what would be the tip of an original rounded Cub wing. Each wing is two feet longer than a stock Cub.
Click to expand...
I guess I assumed from this post that you had the longer 4 hinge ailerons like the Sullivan STC. SJ has that longer squared off wng with the longer aileron and it has really nice aileron responce. I see you have shorter ailerons and longer flaps.
 
The ailerons are very adequate. The wing aileron stops are not installed and the stick stops are set to the maximum travel giving 22.5 degrees up and down. The inboard section of the aileron is not missed. In fact it's space being taken up with the 110" long flaps is a big plus.
 
Yes painting requires special interest and skills. How about this list for tests?

Stability: Fin in front of vertical stabilizer like Cessna's.
Drag: Fairings and fillets around struts - wing (like Maule) and floats. Seal elevator and rudder gaps. Seal elevator trim openings. Minimize cooling drag at the engine.
Floats: Maximize float lift via chine angles (Ed Peck's deal) and side plate bottom scallops. See if suction behind step can be reduced via air injection. Flush riveting the step portion.
Instruments: AOA instrumentation.

There may be more but better than painting.

Gary
 
It's time for me to figure out how to send photos. I have been using a fin in front of the vert stab since I built my exp. 25 yrs. ago. Back then I added it after putting it on floats, but when I recovered it last yr. I built it into the fuselage before covering. I have oversize squared tail feathers and it makes a huge difference. I use cubcrafters gap seals and they also make a marked improvement. The float chine angles from the front to the step on both sides was my own doing when I was competing at the Greenville Flyins every year. Peck liked it and started using a version of it on some of his floats. He and I had many talks about float performance. (And champ wings because he is a champ guy and I was doing a lot of wood spar replacement on champs at that time.) After those float mods, getting it off the step in a short pond was more of an issue than getting out. Have occasionally used forward stick to get it down into the water. On a day with little or no wind I can get out of some places I would have a hard time getting down and stopped in. My wings are also extended and standard length ailerons are pushed out to the tip with the rest inboard is flaps. They came out at 86". Will try to post some pics the next few days.
 
Here's the stability fin from a Husky. I suspect it is the same as Piper's design. photos 080.jpg

Gap seal on the rudder is balsa wood under the finishing tape. photos 079.jpg I don't know why the picture is on it's side?

I wouldn't touch the very successful baffles on the engine as the cooling is perfect.
Drag: it's always good to lose drag. This Cub (on floats) is faster than two of the local PA-12s (on wheels). :lol: This before the wing extension installation with it's small speed increase.
The float lift chine angles have been in use here in the Northeast for decades. Long before Eddie Peck started. They are useful for under powered and under floated planes. Many Flying boats use them.
Flush riveting ahead of the step does help. I flushed the entire forward bottom of a Lake LA-4, it was slippery.
AOA instruments really, do you look at the instrument panel at minimum speeds landing and taking off in tight quarters? The old seat of the pants still works great.
 

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...[/QUOTE]AOA instruments really, do you look at the instrument panel at minimum speeds landing and taking off in tight quarters? The old seat of the pants still works great.[/QUOTE]

If the indicator were forward on the panel top in focus range I'd use it to compare with my pants. For me if I can still see the LZ it's ok and the rest is entertainment.

Gary
 
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