Official Freewing B-2 Spirit Bomber 86" Twin 70mm EDF Jet

[Radar-Guy]

That's exactly what mine looked like on Sunday. Next time I go out I may add 5mm more up up in the elevators, use a smaller lipo and hold in some up during the takeoff run.

Keep us posted, please. I was also thinking about a smaller Lipo, but the 750g battery was needed to achieve the recommended CG (front end 10mm behind the „pilots seats“). Applying full-up elevator, I didn’t even see the slightest tendency to „become light“. I‘m going to look into different wheel layouts.

[RudyD54]

Well that's not very confidence inspiring

I'm going to attempt to maiden mine on Monday. Really hoping I'll be able to get it off the ground. The only EDF I've struggled with getting off our field was the FMS rafale, but getting the CG right and putting on properly sized nozzles sorted it all out.

[Icarus the 2nd]

As an aside, the rotary will adjust the set gains proportionally from ZERO to 100%. If the set gains are 40, 5, 100 and you put the rotary to 50%, you will get 20, 2.5, 50% on the gyro. Turning the rotary to ZERO is basically turning the gyro OFF. You can reduce the set gains but you cannot go above the set gains with the rotary, unless you increase the travel of the rotary above 100%, BUT, this has not been tried (by me) and cannot be confirmed until it has been tried.

I tried it yesterday and could set the gyro gain to nothing so gyro does essentially nothing at all.

I could also increase the gain further than the stock gain and noticed a lot more gyro compensation of all surfaces. In fact I raised the gain A LOT so that I could comfortably check if the elevator surface gyro movement was going in the right direction. With the stock very small elevator gain the gyro barely moved the elevator surfaces.

On a Spektrum tx just set the travel for the channel that controls the gain to 150 in both directions.
On my Frsky tx I did virtually the same by fairing the weight of that channel.

[Icarus the 2nd]

Be very careful about choosing the switch to adjust gains. On Spectrum, the rotary switch should NEVER be used for gains. It is an analog switch and will not retain settings for the model.

If the switch is moved for either a different plane or just bumped, the new position will determine the gain settings at model setup.

Basically if you use the rotary knob, don't expect your settings to be the same as your last flight.

Use a digital trim switch instead, that's what the extra ones are there for.

Really sry, but that's probably the WORST advice I read in a while

I have 30 planes equipped with a gyro on my Spektrum and Frsky radio's with the gain always on the same rotary knob. Each of my planes has a number behind the model name eg. A-4 Skyhawk (3) or Mirage (5). The number corresponds to the gain I need for that plane, like on an analog wristwatch: 3 o'clock on the Rknob for my Skyhawk and 5 o'clock for my Mirage. On a Spektrum tx you can even set a pre flight check for that.

Most gyro users will tell you to use an Rknob for the gyro gain adjustment because it's easiest to use it during your flight.

[mshagg]

Realistically having remote gain is mostly used during tuning. Once you have found the ideal setting you bake that into the gyro proper and don't use the remote dial after.

[T-CAT]

Realistically having remote gain is mostly used during tuning. Once you have found the ideal setting you bake that into the gyro proper and don't use the remote dial after.

Agreed. Once done in that manner, that provides less chance of accidentally touching the dial and altering the gains without intending to do so.

[xviper]

I could also increase the gain further than the stock gain and noticed a lot more gyro compensation of all surfaces. In fact I raised the gain A LOT so that I could comfortably check if the elevator surface gyro movement was going in the right direction. With the stock very small elevator gain the gyro barely moved the elevator surfaces.

On a Spektrum tx just set the travel for the channel that controls the gain to 150 in both directions.

I thought as much but couldn't say for sure as I've not done this yet on any master gain. By going 150 on the travel, do you think you were able to increase the stock gains by 50%?

[Gsky]

Is it possible to fit larger wheels for grass ops? I remember alpha showed some CAD of larger wheels but not sure if there is space in the wheel well.

[Gravythe clown]

Thanks Icarus, That was exactly what I was looking for, I use Frsky so -100 - +100 = 0-100% gain, but you got extra by going to -150 - +150? or was -150 - +150 + 0-100%?

As far as the gain value I use Global values in the model setup and use that as the weight in the the input (Gain). I then use a special function to have a spare trim up and down (I use throttle trim as I don't use because I fly electric only) to add to or subtract to the GV value. I started using this with my helicopters and have since carried it over to the S8/6R receivers.
That way the values is always locked in my model setup and still adjustable relatively easy. Also if I use flight modes I can have and adj gain per mode. Like in my Mirage, I have normal (For fast = low gain) Mid (landings = slightly higher gains) and stunt ( slow High alpha stuff = little more high gains). I can use trim to adj each mode separately and not affect the other modes.
I can't see using anything like all that though for this model, I really don't plan on flying her like the guy in that video making her wings flap. but it would be nice to be able to make minor gain adj if needed while flying.

Thanks again for the info

Gravy

[Aros]

In addition to the confusion some were having about the single wire (AER) connectors where I was going to be adding a section to clarify that, if anyone would care to offer up any other vital bit of information (perhaps Icarus' great insight) please send me the verbiage/breakdown and I will be happy to add that to the online manual as well.

[Gilatrout]

Really sry, but that's probably the WORST advice I read in a while

I have 30 planes equipped with a gyro on my Spektrum and Frsky radio's with the gain always on the same rotary knob. Each of my planes has a number behind the model name eg. A-4 Skyhawk (3) or Mirage (5). The number corresponds to the gain I need for that plane, like on an analog wristwatch: 3 o'clock on the Rknob for my Skyhawk and 5 o'clock for my Mirage. On a Spektrum tx you can even set a pre flight check for that.

Most gyro users will tell you to use an Rknob for the gyro gain adjustment because it's easiest to use it during your flight.

So you have a system that works for you. It doesn't change the fact that with each flight you are only approximating the gains from the last time you flew.

Your workaround is a lot of work. Renaming the plane, setting startup warnings and whatever else. Far better advice is to use the digital trim and be done.

But hey, you be you.

[F106DeltaDart]

Is it possible to fit larger wheels for grass ops? I remember alpha showed some CAD of larger wheels but not sure if there is space in the wheel well.

Alpha was using a twist and turn retract (like the Corsair or MiG 29 mains) to fit the larger wheel in the CAD drawings. If you look at the front side of the gear bay, you can actually see the molded panel lines marking where the bay would need to be expanded to fit this larger wheel. So yes, should be possible but will take some alternate retracts and some foam cutting.

[xviper]

Re: larger single wheel. Those who have this model would be the best ones to comment on this. Take a look at the size of the wheel wells. The way the main wheels are angled, they take up a lot of space and those wheel wells appear to be quite large. I think a fairly large singe wheeled strut could work in there. As for the nose wheel, that might be a limiting factor as the well doesn't look any bigger than any of the other double wheeled nose gears I have (eg. AL-37, PJ50 and assorted military jets).

[F106DeltaDart]

Re: larger single wheel. Those who have this model would be the best ones to comment on this. Take a look at the size of the wheel wells. The way the main wheels are angled, they take up a lot of space and those wheel wells appear to be quite large. I think a fairly large singe wheeled strut could work in there. As for the nose wheel, that might be a limiting factor as the well doesn't look any bigger than any of the other double wheeled nose gears I have (eg. AL-37, PJ50 and assorted military jets).

Doing some quick measurements, it looks like the largest wheel you could fit in the stock bay would be around 2.5” diameter. Of course, you’d either need to swap struts, or reconfigure the stock struts to grip a single axle instead of the bogie arrangement.

[GliderGuy]

It FITS!

You can see how ramekin cups (P-38 wheels on top shelf) do a great job holding wheels. Then I use mini-bungees secure the wheels into the cups.

Ramekin cups fit large MiG wheels, too. WalMart has them. Glue them down with RTV silicon rubber. Then you can simply twist them off should you need to haul something. Then re-glue.

Look closely on either side of the B-2’s right main. The mains won’t fit ramekin cups I have. You will see a black clip on either side of the right main. I will run a mini-bungee from clip-to-clip across the main to secure it.

One mini-bungee wraps around the base of the nose gear’s ramekin. Then a second mini-bungee clips to the base bungee goes across the nose wheel and clips to the base bungee’s opposite side.

Secure a main and the nose….you’re done.

As a final touch, I used the shipping crate’s plywood planks to bridge the truck bed depressions. Now, the main gear trucks sit level on the plywood bridges and are under considerably less stress.

Someone suggested keeping the crate’s nice plywood. Bless that person!

For those with nicely carpeted beds, use Velcro to secure the ramekin cups to the carpet.

Now if only the wind would stop blowing!!!!

-GG

[xviper]

Doing some quick measurements, it looks like the largest wheel you could fit in the stock bay would be around 2.5” diameter. Of course, you’d either need to swap struts, or reconfigure the stock struts to grip a single axle instead of the bogie arrangement.

I think someone mentioned just swapping in a complete set of struts/tires from another plane. Perhaps known trailing links that have worked well on other planes.

[osuzoo08]

Has anyone had luck flying off of grass? My club only has a grass runway and my B-2 arrives tomorrow. I am wondering if i should just do a return right away

[ridgerunner]

I said it before and I'll say it again...
This plane has a light wing loading with plenty of thrust from the twin EDFs and should have no problem quickly lifting off pavement or grass within a relatively short distance. The gear mechanisms are just fine the way they are. Its the wing's lack of sufficient positive AOA when sitting on the gear and rushing down the runway that appears to be the root cause of the problem. The failed grass launch videos make it appear that it may actually be generating negative lift as it speeds up pinning it down and preventing it from getting up to speed. A simple solution is to simply give it a bit more positive AOA by raising the nose a wee bit. This way, it will generate more lift as it picks up speed and allow the load on the gear (and its drag) to quickly decrease. Note that the CG position has nothing to do with this simple geometry issue - its all about Angle of Attack when sitting on the gear. Once again, IMHO.

[Aros]

Has anyone had luck flying off of grass? My club only has a grass runway and my B-2 arrives tomorrow. I am wondering if i should just do a return right away

It really depends on the shape and shortness of your grass. A golf green? Sure! It will take off on that but let's be honest, most clubs don't have golf green short and manicured grass on that level. These wheels and struts are small-ish...You are asking a lot to overcome that friction even on a decently manicured grass runway of an inch or two. I never once looked at this model as grass friendly. This screams paved runway. Now ridgerunner has some great advice. Raise the nose, aka AOA and you could find success.

[mshagg]

Based on the CAD work in the live stream i was picturing a solution where you simply swap in the lower part of the strut from something like an me262 oleo. Just need to find something that fits in the upper half of the strut and has appropriate clearances. Perhaps the wheel trucks can be removed completely and swap in a more conventional axle.

The B2 struts do look fairly robust so some mesure, fit and testing would be needed. https://www.motionrc.com/products/fr...085#hash-tab-5