hipik634

In one hour

hipik634

https://youtu.be/30 so it can go on the tooth, so it will get up, after some more checks .. From different airfield, of course

FlyerInOKC

My Feedback: (6)

I can't blame you I wouldn't want to try and clear the railing of the fire pool either!

hipik634

Today i went to the river and had a high speed taxi test, it tends to rotate if it hits the side float, the engine power for take off is really close call, but it will go, i just have to be careful not to tear its of to early

FlyerInOKC

My Feedback: (6)

Well good luck with the maiden flight!

hipik634

actually the water level si quite high now due to show melting, so I imagined myself trying to recover the plane if something goes wrong I almost had the takeoff speed, so I hope all goes well on next try


https://youtu.be/uvx7

FlyerInOKC

My Feedback: (6)

She looks like she wants to fly!

BigTeeEldorado

Some float planes I've had needed to get going pretty fast in order to come up on step. Be careful not to move the CG too far aft, that would be disastrous when you do get it airborne. That is why I was asking if you still plan to put the wheels on it. For my two cents I would rather see the first flights off land so you do get the CG right for flight first and then work with the water handling.

hipik634

The wheels are intended to be put on later, there is a problem with wheel size and dampening system. I'll stick to plan cg for the first flight. I will just go to some still water, not river for the maiden. One less factor to wind and temperature ..

hipik634

well, it didn't go well on maiden, I haven't been able to get it from water in flyable condition, something is wrong, maybe low engine power. I intend to replace 3542 with 3548, lets see after that.

BigTeeEldorado

It might be under powered, it did seem to act like a slow speed tip stall. It is hard to tell from the video but if you were pulling hard up elevator I would say under powered. If you were not pulling up elevator it might be tail heavy.

That was a cool little retrieval device yo have there too.

hipik634

next tries with upgraded engine to 3548

BigTeeEldorado

There are so many factors to consider especially with the motor mounted above the wing. I have a 1/4 scale ultralight with a pusher motor mounted just under the wing but like yours the bulk of the weight is below the thrust line. It was hard to get it airborne at first and when I did it porpoised up and down across the sky whenever I added power. Landings were a one chance only affair because adding power low and slow was dangerous. So I read several articles on what angle to mount the motor when most of the weight is under the motor and it can be surprising how much angle is needed. You get a rotational force that tends to drive the nose down when power is applied unless you angle the thrust line to go through the center of the mass. In your case it seems to get up on step and skim across the water fine but as soon as the plane breaks free of the water it looks like it wants to nose over forward. You are trying to pull up which causes the tip stalls and/or the nose is coming back down in contact with the water and spinning you around.

Just trying to help but you might want to do some research on thrust angle for pod mounted engines and see if the thrust angle might be your issue as much as balance.

Hang in there, I have all the confidence you will figure it out.



ps check out my U-Tube channel (there is a link in my signature below) and you will find several videos of the ultralight model with some on water.

hipik634

I added some washers under the engine mount to point it right, rechecked balance (5g off), reset the ailerons. Next try as weather allows, it might be also an issue with spinning forces from the three bladed prop, as it probably has these forces greater than a two bladed one

FlyerInOKC

My Feedback: (6)

Keep at it you will get it into the air!

hipik634

I got it, for a while before the wings struts failed, repairable



GUYS, I am looking for RC modeller february 1997 , I have to find out, what is the projected weight of the plane. I think its way too heavy.


https://www.youtube.com/watch?v=H42iQ6lYnL8&index=18&list=PLkg3v72zblUzCgvk6UOa4TINnvVZwHV5G

BigTeeEldorado

http://www.magazineexchange.co.uk/RC-Modeller-1997/

hipik634

sorry, not RC modeller, but radio modeller http://www.magazineexchange.co.uk/radio-modeller-magazine-february-1997-issue.html?&cat=0 but N/A

ok, this is what I will do, made a Clark-Y profiles on http://airfoiltools.com/plotter/index with higher area

I will make a bigger wing, now I have loading 100 g/dm2 after I would go to 75 , that would be much easier to fly; with required speed to take off with this loading I lost my wings

i will make it 25% bigger that will make move from 100 to 65 and all will be fine

FlyerInOKC

My Feedback: (6)

You make it sound so easy! Then the building starts! ;-)

hipik634

well, after some consulations there are the outcomes:
- single wing area has to be at least 20 dm2 for the weight ratio 2600g/40dm2 = 65
- the floats wings has to be at least very close to good profile
- the profile on original plan is very unoptimal - going for the CLARK-Y
- the middle wing section of the wing - it has to be reworked - could work for 1000g but not for 2500 - will replace with a rod supported holder
- the diheral angle is too low
- THE WING HAS NO MASTER BEAM (dual beams in CG - torsion box) - have to rework it, on high load it just bends and looses lift.

I will post the plan as it will be available

FlyerInOKC

My Feedback: (6)

Your analysis sounds to be very thought out and complete. The wing will need to be completely redsigned but I think you will get there.

hipik634

working on it

hipik634

i think, that for the intended purpose I dont have to make full details on conflictin parts in the middle section.

FlyerInOKC

My Feedback: (6)

Good enough!

BigTeeEldorado

Nice Work!!