Official Freewing 64mm Lippisch P.15 Thread

[Hardway]

Fly, that is just too cool. Welcome!!! Jerry

[FlyGonz]

Well it wouldn't fly. Maybe the wings were too heavy or just aerodynamics were off. Oh well, worth the try.

[xviper]

Well it wouldn't fly. Maybe the wings were too heavy or just aerodynamics were off. Oh well, worth the try.

I think it became way too big of wingspan for it's length. Did it waddle like a duck on the ground? Swayed left/right into the dirt? It probably needed a very tall, long rudder to stop the waddle. I remember someone (Tired Iron?) made a twin Lippy and flew fairly well.

[FlyGonz]

Twin lips work great. I probably should of just done that lol. But in the end it would just roll to the right. I checked CG and weight was even. Controls and trim were fine. But alas... The experiment failed. Time for a new plane lol. The airframe took too much damage to bither repairing.

[xviper]

Twin lips work great. I probably should of just done that lol. But in the end it would just roll to the right. I checked CG and weight was even. Controls and trim were fine. But alas... The experiment failed. Time for a new plane lol. The airframe took too much damage to bither repairing.

Been there, done that. Still fun to try. I built a twin FT Viggen. It flew for about 30 feet.

[FlyGonz]

That sounds fun! Now I just plan to stick to props. I am an intermediate pilot. I just want a plane with about a 50" wingspan that is faster than my Carbon Cub S. Any suggestions?

[Skyboom]

Are you able to put the lippy back together normally again. Then buy a fuselage for the longer wiings. And presto. ...

[xviper]

That sounds fun! Now I just plan to stick to props. I am an intermediate pilot. I just want a plane with about a 50" wingspan that is faster than my Carbon Cub S. Any suggestions?

As a matter of fact, I do. Next spring, after I've sold my modded FMS 1450mm P-51, I'm going to get the new Eflite 1.5m Mustang. It's high quality, very fast, but it's pricey. Take a look at it. It might fit the bill.

[FlyGonz]

I thought warbirds took a lot of rudder to fly properly? I usually stay away from them for that reason.

[xviper]

I thought warbirds took a lot of rudder to fly properly? I usually stay away from them for that reason.

Not when flying. It takes a bit of rudder control to get it to go down the runway straight and to take off straight due to the torque from those big props. But once in the air, they are solid and fast. Any fast prop plane, even ones with trike gear can have a lot of torque steer. You just have to know how to manage it. If you want something really fast, the best way to go is a big pusher prop that you hand launch. Those can also torque roll on launch. Of course, it depends on what you consider "fast". Almost any of the new prop planes will be faster than a Carbon Cub S, which I estimate at a top speed of around 60 mph in a straight & level flight. You can power dive any plane to go really fast but that's using something other than what the plane has to do it. My criteria for "fast" is 90 - 100+ mph. To get anything over a 50" wingspan to go that fast out of the box takes quite a bit of power. It's easier to go fast with a smaller plane (in the 1m size or less).

[FlyGonz]

Cool. Thanks for all the info! I will look around and see what I can come up with.

[themudduck]

The Lippy (and the ME163 Komet) are flying wings, and flying wings have complicated aerodynamics. If you look at these planes closely you'll see they have a significant amount of reflex (twist) built into the wing, and of course they all have a significant taper and a swept-back design. You can see this kind of design on many RC flying wings as well by looking at Google, but you'll see very few long straight wings. Straight wings don't work well as a flying wing.

Here are a few pics of a few famous Northrop designs, the N9 and the B49.

[JayP]

I got another one of these to build over Christmas time. I'm debating whether to keep it stock or not. I have an FMS 3150kv 11 blade unit that needs balancing, but will handle 5s with a good 70A ESC. I have some 5s 1300 packs, which might make it difficult to get CG right, but maybe not impossible? Or an RCBlog 12 blade unit, currently with no motor, that could run a 3-4-5s motor, depending on how crazy I want to go. Maybe the motor from my v1 Habu, with a solid but lightweight 4s pack? The possibilities are endless!

[Kahmed]

I absolutely hated this thing the first few times I tried hand launching. Then I tried it with the landing gear. Absolutely amazing. No detriment to performance and super fun to fly. I need another one just because it’s so cool.

[JayP]

Same here man. I had about a 50/50 success rate at first, but I loved flying it when it worked. One time I got really frustrated and just chucked it straight up with full throttle as hard as I could, and that was it. That’s how I launch it now.

[ridgerunner]

Purchased two of these and yesterday maidened number one. A few first impression comments...

• This thing is small and fast and gets out of sight quickly and easily. Thus, it should come in a highly visible bright color scheme! (and/or in unfinished white so that we can paint it ourselves) - the stock darkish green is hard to paint over.
• The belly should come with a (replacable) indestructo plastic skid.
• Aerodynamically, pulling air from the bottom of the wing is NOT a good idea - air forced to go upwards into the wing inlets reacts on the airframe with a downward (negative lifting) force. Keep the hand holds, but plug them up, EDF-wise, - this should improve the powered flight performance and reduce the downward launching tendency. (Or move the wing EDF inlet holes on top of the wing?)

Note that this is the first time I've flown an EDF - man it sounds cool!

[JayP]

All very good points, ridgerunner. Take a look at Team Associated Chassis Protective covers here:

https://www.amainhobbies.com/team-associated-chassis-protective-sheet-asc9787/p16652

They’re really strong vinyl and very smooth so they’ll glide across grass or pavement easily.

[xviper]

this should improve the powered flight performance and reduce the downward launching tendency.

This tendency is not restricted to this plane nor to EDFs. Hand launched prop planes, particularly delta wing types have this same tendency. Most of them tend to dip a little just after release and if the launch is just a little "off", it can head for dirt in an alarming fashion. This "perceived" vacuum effect is minimal. The quick and easy fix to this is to build in a small amount of reflex (about 3 degrees) on a switch. This will combat the dip and once enough air speed is achieved for flight, flip the switch to take out the reflex. Allowing a second or two for the fan to spool up to max will minimize and/or eliminate any torque roll on launch.
Insofar at belly scraping, I apply a layer of clear Gorilla tape to the underside, however, now that I've learned how to "plop" the landing, there is little scraping going on. For visibility, I've got fluorescent pink wingtips but even this will disappear at around 300 to 400 feet distance. A solid pink plane can still disappear and turn to grey/black. One just has to learn to fly this plane within a smaller volume of airspace and limit max throttle to high speed maneuvers near the pilot.

[JayP]

This dip doesn’t just happen on launch, though. With open cheaters, mine would do it when I punch the throttle in a level pass, if I was gliding by with little to no power and go for a punch out. Closing the cheaters by putting a piece of clear tape inside the duct has corrected that for me. Launches are a little easier, and punching out on a level pass doesn’t dip like it used to. Others on RCG have reported a little higher top end from closing the cheaters, but I can’t tell on mine.

[xviper]

I won't argue with your view point as to why the dip occurs. Early in these threads (on both forums), this "power on" dip was also attributed to the design of the exhaust tube. It caused the thrust to be directed down and when you punched it, the plane would dip. It was quickly discovered that reaming the tail cone on the top 1/2 near the end lip and also adding a small piece of overhead projector sheet in a key location eliminated the "down" direction of the thrust exhaust and hence, no more dip when opening up the throttle, even on a level cruising pass.