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

[F106DeltaDart]

Great job F106. I too have never flown it with that clear plastic fin. It went in the trash with the box as soon as I finished putting the B2 together. Did you play much with the rudder control during flight? I find it very useful to pre load bank turns, kind of like with the F-15. I have also now flown her with 10-12 mph crosswinds and notice no tendencies to weathervane.

Gravy

Thanks, I played with the rudder quite a bit in flight, and was surprised at how well it behaves. Kind of reminds me of a heading hold heli in the turns. Starting with rudder helps, and feeding in more as bank angle increases. Your braver than I playing with crosswinds, but that’s impressive performance!

[ridgerunner]

Does anyone know what the drag rudder settings are for the full-size B-2 during take offs and landings?

[F106DeltaDart]

Does anyone know what the drag rudder settings are for the full-size B-2 during take offs and landings?

Here’s few reference photos that may help. The shot with the gear retracting is takeoff. Looks like a mid open setting, similar to what most are flying the B-2 with. The shot from the underside is landing, and they are both opened to ~45 deg ish to act as speed brakes.

[GliderGuy]

Does anyone know what the drag rudder settings are for the full-size B-2 during take offs and landings?

Check out 27:23 and 27:32 in the video….

https://m.youtube.com/watch?v=Mr-LDUYdB2c

29:20 shows post landing fully open drag config.

-GG

[davegee]

Thanks, I played with the rudder quite a bit in flight, and was surprised at how well it behaves. Kind of reminds me of a heading hold heli in the turns. Starting with rudder helps, and feeding in more as bank angle increases. Your braver than I playing with crosswinds, but that’s impressive performance!

I have found the same thing on the 11 flights I have so far on my B-2. I only have about 3 flights without the clear plastic fin, but on those flights without it I didn't have any unexpected control issue; I knew it would take more rudder in the turns, and it was quite predictable how much pressure I would need on the sticks to carve out a good turn. Having said that, I don't plan on flying this plane with much or any crosswinds, if I can avoid it. I'll save those for the more adventurous and capable pilots of this remarkable plane other than myself!

[GliderGuy]

The B-2 forum has been VERY quiet, of late. Hold on to your hats...I'm probably about to light it up with this post.

First...Do not consider this a disparaging post about the B-2. I love flying the B-2, BUT I NEED HELP! (help, that is...other than the offer to give me of a box of nose gear servos...LOL).

Second…I’m hoping this post doesn’t start a series of bad comments. The B-2 deserves better than that. She’s beautiful in the air. Looking for assistance to solve a challenging characteristic that may have a simple solution. Thanks.

The PROBLEM: After a couple of hundred flights in all types of conditions, on average about every 50 or 60 flights, I am replacing the nose gear servo.

QUESTION...DO WE HAVE ANOTHER A-10 "TOO FORWARD OF A CG" ISSUE WITH THE B-2 THAT HAS A SIMPLE FIX LIKE THE A-10 DOES?

For those of you who have flying wing experience, how far aft can a flying wing CG get? OK...don't answer this yet.

Today, the weather was perfect. 2 to 5 knots straight down the paved runway. I mean with the P-38, MiG-29, F-4, AL37, A-10 (with CG moved back) and PJ-50 birds....you could close your eyes and make good landings 100% of the time. I made several P-38 and F-4 landings today....duck soup!

Today I worked HARD at making every B-2 landing GREAT! She lands so easily in these conditions. I touch down with as low an energy as possible...sticks like glue = smooth touchdowns.

Fifteen landings were perfect...loads of fun. Then number 16 came along, and she got a wee bit wonky, skipped a tiny bit...not enough for a go-around, did a little MAIN, MAIN, NOSE GEAR dance and put some loads on the nose gear and bent the worm drive gear. Dang It! AGAIN!!! The loads on that servo must be sooooo high with that big battery nearly on top. The servo now goes woo, woo, woo, and pulsates rapidly as it retracts or extends. I took a bent servo apart the other day, but it doesn't look like you can get the long worm drive gear off the motor shaft to straighten it. UGH. Am I wrong? Can they be fixed?

If you've only made a few flights with your B-2 and have had great landings so far, just wait! Your turn is coming. Sorry to be the bearer of bad news. Order some replacement servos...NOW!

Stated again, I need help from those of you who have flying wing experience. Even better, those of you who have flown the B-2 and experimented with moving the CG back. Alpha? Tom? James? Aros?

I fly with the Admiral Pro 6000 hanging about 1/2 an inch off the battery tray to the rear....like Jame's YouTube video. It flies good with that CG...albeit the CG is still forward as most EDFs are recommended from the factory manuals (the "why" has been discussed a lot in several forums and posts). <A given for the B-2 with the amount of up elevator trim one carries per video recommendations>.....

Now the other question: How far aft can the B-2's CG be moved from the "book" location and still be safe to fly? Anything to reduce the loads on that nose gear servo...HELP!

Thanks in advance, All suggestions are welcome, but a REAL SOLUTION is what is wanted.

-GG

P.S. Ordering more nose gear servos.

Edit: What about a 3D printed support/brace like for the A-10? Could it be that simple of a solution? I don’t have the equipment.

[xviper]

I'm sorry but a REAL SOLUTION may not be forthcoming from me. However ..................
I have a bit of flying wing experience - Starting way back with the Eflite Scimitar. That one was quite easy to land each and every time. Then comes the X-8 wing, Zeta FX79 Buffalo, the 2.0m Opterra, 1.2m Opterra, HobbyKing Sonic, Pirana. It should be noted that the Scimitar was the only plane that had gear and ALL of the aforementioned are wings WITH some kind of significant vertical stabilizer or really big winglets. NONE of these planes have had any problems with landing smoothly in a consistent manner, so I've never had the need to play with their CGs. I have had things that their manufacturers called "wings" but I think they were stretching the truth. Those had too far aft a CG and were nearly uncontrollable, acting more like a roller coaster that even a gyro could not fix.
With this B-2, landing for me, has been a haphazard kind of thing. One landing in 3 has been "eventful". The first bounced landing created the most damage but that was not major and was easily fixed. Another botched landing did no damage at all as it flip over and landed perfectly upside down. I've never actually had a bounced landing where the nose gear took much of a hit. I'm sure it's coming. That's sort of why I don't fly my B-2 that much. I don't use the provide clear fin as I don't think it's big enough to actually do anything. If I thought I could get away with it, I'd try a belly landing just to see if it would be smoother and easier but I fear that those drag rudders being open like that could get toasted. I suppose I could do a mix and collapse them on a switch like I did to open them up fully to use as drag brakes. I just don't know what would happen if I collapsed them too soon prior to touch down. I worry something really bad.

[Evan D]

The worm gear is pressed onto the motor shaft and I've straightened the worm gear but left it on the motor. My ball link pliers have perfect (I think about 4mm) half moon cutouts that can grasp the worm gear without flattening the very delicate threads. I was able to straighten mine about 95%. Not perfect and works without the jerky retract and extension. I'll be no help with balance. My flights were at about 5 behind the marks but I'm not flying her any more.

[GliderGuy]

Maybe someone with 3D printing equip could design a brace like was done for the A-10?

-GG

[Evan D]

Not sure why you are saying specifically the A-10 as many aircraft that have retracts that extend aft have braces designed for them including the A-10. The B-2 on the other hand extend forward so you can't have a brace behind it.

[GliderGuy]

Good point!

[davegee]

Hi All: I have replaced the nose gear and retract due to a hard landing some time ago. Flies fine for now, but have a question: What settings for Expo and rates do you use on your B-2? I am flying from a very rough runway and the nose gear steering feels like it's on the head of a pin. I'm really oversteering it a lot. I have ordered an Assan steering gyro, but it is still enroute to my house. Any ideas for settings for more manageable nose gear steering in the meantime?

Thanks,

Davegee

[GliderGuy]

Hi All: I have replaced the nose gear and retract due to a hard landing some time ago. Flies fine for now, but have a question: What settings for Expo and rates do you use on your B-2? I am flying from a very rough runway and the nose gear steering feels like it's on the head of a pin. I'm really oversteering it a lot. I have ordered an Assan steering gyro, but it is still enroute to my house. Any ideas for settings for more manageable nose gear steering in the meantime?

Thanks,

Davegee

Hi Davegee,

For mine: No Expo, No dual rate, throws by the book.

Sorry….not much help.

-GG

[xviper]

Hi All: I have replaced the nose gear and retract due to a hard landing some time ago. Flies fine for now, but have a question: What settings for Expo and rates do you use on your B-2? I am flying from a very rough runway and the nose gear steering feels like it's on the head of a pin. I'm really oversteering it a lot. I have ordered an Assan steering gyro, but it is still enroute to my house. Any ideas for settings for more manageable nose gear steering in the meantime?

Thanks,

Davegee

No rates or expo for mine. The supplied electronics seem to have it dialed the way it flies best. Expo is a matter of personal taste. Insofar as rates go, I wouldn't touch the AIL rates as it's already very slow response. Elevator could use a little lower rate but I just operate the ELE stick gently and it's fine. Rudder needs to be what it is.
The "oversteering" situation is very common for this plane due to its short wheelbase. The RUD gain is set from the factory at 100%, however, it does nothing for the ground steering. There is no real answer to this problem while you are waiting for the Assan. Try to take off straight into the wind. If there's a crosswind, fly something else. Crosswinds will add to an already tricky situation with the ground bumps. For that, the Assan is the way to go. You'll remove the steering servo from the control box and hook it via a Y directly to the RX. From there, the Assan gets spliced in.

[davegee]

No rates or expo for mine. The supplied electronics seem to have it dialed the way it flies best. Expo is a matter of personal taste. Insofar as rates go, I wouldn't touch the AIL rates as it's already very slow response. Elevator could use a little lower rate but I just operate the ELE stick gently and it's fine. Rudder needs to be what it is.
The "oversteering" situation is very common for this plane due to its short wheelbase. The RUD gain is set from the factory at 100%, however, it does nothing for the ground steering. There is no real answer to this problem while you are waiting for the Assan. Try to take off straight into the wind. If there's a crosswind, fly something else. Crosswinds will add to an already tricky situation with the ground bumps. For that, the Assan is the way to go. You'll remove the steering servo from the control box and hook it via a Y directly to the RX. From there, the Assan gets spliced in.

Thanks, XViper. That's pretty much what I have set up in my plane now. No rates and no expo. The rough runway that I operate from is really the devil for this plane. This morning, even though trying to find a stretch of runway with not too much in the way of bumps and gaps, I hit one when the plane was pretty much too slow to fly but here it was about 3 feet high!
All I could do was try to get the wings level and a shallow climb and I got it out of there. Flight was no problem, as usual, but it is possible that on takeoff one of the main gear mounts had been loosened and when it landed that gear and mount pulled out. Just minor scrapes and some epoxy to put the mount back in. Amazing how little glue they use to put the mounts in!

Good points on the winds for this airplane, and ones I always try to adhere to. I might wait to fly it next time with the Assan gyro installed. It is supposed to be here tomorrow. We'll see. If I have any questions on the setup, I'll drop you a line.

Thanks!

Davegee

[xviper]

I might wait to fly it next time with the Assan gyro installed. It is supposed to be here tomorrow. We'll see. If I have any questions on the setup, I'll drop you a line.

Thanks!

Davegee

After I installed the Assan, there was still one take off where it hit a bump and went 90 degrees. In certain conditions, even Assan can't perform miracles. Our runway is Geotex but it needs to be rolled to iron out the lumps and bumps. Until that happens, I try my best to pick the smoothest strip of runway I can find to take off. On the most part, once it gets a straight start and can stay straight for a couple dozen feet, I give 'er and get it in the air as soon as possible.

[davegee]

After I installed the Assan, there was still one take off where it hit a bump and went 90 degrees. In certain conditions, even Assan can't perform miracles. Our runway is Geotex but it needs to be rolled to iron out the lumps and bumps. Until that happens, I try my best to pick the smoothest strip of runway I can find to take off. On the most part, once it gets a straight start and can stay straight for a couple dozen feet, I give 'er and get it in the air as soon as possible.

Well, got the AG61 steering servo in the mail today. Was pretty simple to set up, and I think I did it correctly, as far as I can tell. When I first powered up the airplane, the nose wheel steering didn't work at all, so I went to the next step of doing the Auto Config procedure. Every time I powered the airplane up, the Assan gyro flashes rapidly for a few seconds, and then goes to a steady slow flashing of the blue light. I did try moving the rudder stick right after powering up, moving it about 10 times from stop to stop, and then holding it to full left rudder position.

Tried all this several times, rechecked the wires, plugged them in again, but still no joy, the nose wheel doesn't respond to any commands throughout all of this.

Any suggestions? It's probably operator error as I haven't ever done a nose wheel servo like this before, but I'm stumped, for the moment.

Appreciate any help on this.

Thanks!

davegee

[xviper]

I had to do the config several times for it to take. The steering must be connected directly to the Rudder channel via a Y. The other lead from the Y goes to the control box as usual. That controls the flying rudder. The Assan then intervenes into the signal path between the RX and the steering servo. Plug the steering servo into the Assan as labeled. Plug the steering signal from the Assan to the Y. Nose gear must also be isolated from the control box. Remove nose gear servo lead from control box and plug into Assan. The gear lead from the Assan can then go back into the control box. When doing the config, the gear must be down to start. Depower the plane and plug battery back in. As soon as the Assan starts it's blinking sequence, immediately begin the left/right rudder stick movement BUT as fast as you can, stopping on the left side when you've done at least 5 cycles and hold it there till the Assan acknowledges it. If you don't do it fast enough, it won't recognize the config procedure. I can't remember if you do this when you see the light flash quickly or slowly. Check the instructions. The rudder rate must also be at least 100%. Try going to 125%.
PS. If the wiring is done correctly, you should get some steering response by moving the rudder stick, even before you do the config. It may not respond in the correct direction but it should still move the steering wheel.

[kallend]

Well, got the AG61 steering servo in the mail today. Was pretty simple to set up, and I think I did it correctly, as far as I can tell. When I first powered up the airplane, the nose wheel steering didn't work at all, so I went to the next step of doing the Auto Config procedure. Every time I powered the airplane up, the Assan gyro flashes rapidly for a few seconds, and then goes to a steady slow flashing of the blue light. I did try moving the rudder stick right after powering up, moving it about 10 times from stop to stop, and then holding it to full left rudder position.

Tried all this several times, rechecked the wires, plugged them in again, but still no joy, the nose wheel doesn't respond to any commands throughout all of this.

Any suggestions? It's probably operator error as I haven't ever done a nose wheel servo like this before, but I'm stumped, for the moment.

Appreciate any help on this.

Thanks!

davegee

I've set up several and never had a problem. Mostly the default setup has worked, only once did I need to go through the configuration routine.

Did the nosewheel respond to yawing motion of the model (as opposed to moving the rudder stick? The stick response is quite insensitive, probably to avoid overcontrolling).

Also it's possible that it is interpreting the gear channel in reverse, since the gyro doesn't pass along steering commands when (it thinks) the gear is up. If that's the case you need to run the setup again, carefully following the directions.

[davegee]

I've set up several and never had a problem. Mostly the default setup has worked, only once did I need to go through the configuration routine.

Did the nosewheel respond to yawing motion of the model (as opposed to moving the rudder stick? The stick response is quite insensitive, probably to avoid overcontrolling).

Also it's possible that it is interpreting the gear channel in reverse, since the gyro doesn't pass along steering commands when (it thinks) the gear is up. If that's the case you need to run the setup again, carefully following the directions.

Thanks, Kallend. I'm guessing that the gyro itself doesn't have any problems, it's something with my set up, or possibly something like the gear down signal isn't getting through to the gyro, maybe thinking that the gear is still up? I did reverse the gear switch on my radio, hoping that might have something to do with it, but so far no luck.

When I go strictly by the instructions in the little pamphlet that comes with the servo, I tried to do everything just as they asked. XViper has suggested that it might need a Y cable in there, I don't have any spares available right now, but have ordered a couple to have around.

What I simply did, per the instructions, was take the nose retract cable and plug it into the Gear Out on the gyro. The red Gear In was plugged into where I had the retract servo plug going in originally. Same for the steering servo cable. I plugged it into the Turning Servo plug on the gyro, and the Turning In male plug went into the spot where the steering servo plug had been. That's pretty simple, I thought it should have worked. But when I have things plugged in the way I THINK it should have been per the instructions. The nosewheel doesn't turn at all. Works fine when I have the gyro removed, though.

I think I'll try the gyro in another plane like my Freewing F-18 just to see how it works with it. If it works normally, I can deduce that the gyro is clear of any issues, I just have to get it to work on the B-2.

Thanks,

davegee