Slender Tender & Tall -back at it again

[Paul Taylor]

Ok guys We have solved the one issue with this plane doing the flyaway on the up leg of the hourglass. (Removed the pipe and replaced with header.
Now today it did something weird on the down leg. It seem to roll out and in. My butt made a pucker sound.

So after the flight we talked about it and the thought its either too much flap throw or the flaps are too wide.

Kit Vector with a PA 40 UL

Thoughts?

Thanks in advance
Paul

[Steve Thompson]

Hmmm, I have heard of the Fox burp, but the pucker sound has me completely baffled.   Heeee

[Mark Scarborough]

first question, has it done it more than once?
if its one time, then its bad air, if it does it everytime then its a trim issue

Trim, first question, are the wings perfectly level upright and inverted
second, if they are does it drop or pop a wingtip in the squares
third question are you positive you are manuevering dead downwind

[Paul Taylor]

Good question Mark. It's the first time. I was too skert to try and repeat to roll or the pucker sound.
So maybe we try it again next time out.

Still wonder about the flaps. Too much deflection or size?
Will post some pics later.
Stay tuned.

[Mark Scarborough]

If its a Stock Vector built per the plans I cannot imagine to much flaps? Lots of those flying with stock config. you did set the flaps to elevator ratio per plans? Its more likely warp, or something along those lines.I know my most recent Impact would wag a wing hard until I got the wings perfectly level.

[Mike Haverly]

You removed the pipe and changed the CG, a lot.  

[Randy Cuberly]

Pretty much impossible to tell exactly what is happening from the available data.  I will say that the third corner of the hourglass is a very likely place to induce a stall if the airplane is a bit slow or the power is not up to par...You change from a pipe to a header would have moved the CG forward if you didn't adjust it by adding some tail weight.  This could require you to use more control to affect the turn and that could result in a stall if the factors mentioned before were present!
On early test flights when a lot of unknowns are present it's best to avoid the hour glass until you sure of the airplanes trim.  Good place to lose a poorly trimmed or slow airplane.

Randy Cuberly

[Gerald Arana]

Paul,

Have you checked the flaps to see if one is more flexable than the other?  This will definitely cause weird stuff to happen.

Good luck, Jerry

[john e. holliday]

First flight jitters.  If you have read any of the trim set ups, especially Windy's article.  First flight is get engine setting correct with wings level checking both up right and inverted doing  gentle half loops or half loops to start.  Then the next step is to get tracking through loops both waays.   Finally try the saures both ways.   Once you are happy then try the pattern.  I hope you ahve some help watching your flights.

[wwwarbird]

 As long as the pucker stays as only a sound you're still good. 

[Reptoid]

Why is it that people refuse to follow the advice given on this forum over and over and then ask questions about problems using solutions that aren't related to the problem? Please refer to the trimming links provided on this forum and others. Bench trim before flying; then follow the trim charts in the order listed. Do not proceed to complex, difficult maneuvers if your airplane has basic trim problems. Things like tip weight, warps, alignment issues, etc. do not heal themselves and only aggravate other trim issues

[john e. holliday]

Hey, we all have to learn and reading takes too much time.  Nothing like experience to make you learn things even though using the experience of others speed things up.

[Paul Taylor]

Wow this thread is back from 2016!!!!

I guess it is Throw Back Thursday.

[wwwarbird]

Wow this thread is back from 2016!!!!

I guess it is Throw Back Thursday.

 Oh wow, didn't even notice that, hopefully the puckering has run it's course.

[Paul Taylor]

Why is it that people refuse to follow the advice given on this forum over and over and then ask questions about problems using solutions that aren't related to the problem? Please refer to the trimming links provided on this forum and others. Bench trim before flying; then follow the trim charts in the order listed. Do not proceed to complex, difficult maneuvers if your airplane has basic trim problems. Things like tip weight, warps, alignment issues, etc. do not heal themselves and only aggravate other trim issues

Not sure who you are but you’re making a BIG assumption.
There are several people on here that I will always listen to their friendly advice.
I will be the first to admit I’m an average builder and can do basic trim. I have learned a ton from people on the boards and I have been on Stunthangar from day one and still learning.
I am the one who pinned Paul Walkers trim sheet to the boards.
If you have something positive to share please do. If you want to try and troll people try Twitter.
This was an old post and I was asking for help and got some positive feedback. I alway disregard negative information but not this time.
Stay salty. 

[Paul Taylor]

Oh wow, didn't even notice that, hopefully the puckering has run it's course.

For the most part I have resolved that problem but on a windy day it may happen. 🤣