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

[Hugh Wiedman]

I used a well maintained battery, IR values in the 4,x range.

For some reason, those IR values seem high to me. I assume you're talking about individual cell IR's in mohms, no? As some of you know, I've been way too deep in testing different batteries for the last few years and using the Progressive IR meter, I've gotten the following results on various 6S batteries:
SMC 8100: 1.8-1.6, SMC 6200: 1.37-1.14, SMC 5300: 1.61-1.42, HRB 6000: 1.97-1.79, Roaring Top 6250: 3.21-2.96, Admiral 6000: Pro 3.27-2.96 Admiral 5000: 4.01-3.64.

As far as power draws, your numbers look OK, but I've found that the difference between an Admiral 5000 at the high end of the IR curve and say the SMC 5300 results in at least 8-10 Ah more and about about 250-300 Watts more. Out of curiosity, what pack are you using?

[kallend]

I thought about that diagram myself but there's one potential anomaly ..................................... Notice how the gain (G) pin on the gyro is fed by the black (dark) wire of the 3 wire lead? Then it goes (single wire) to the "master gain" port at the RX. (The HE and E-52 gyro uses a 3-wire lead than ends in 3 separate single wires with their own plugs. A private individual would use a standard 3-wire to 3-wire female/female extension.) .

I'm a "private individual" and I had no problem connecting it up correctly, based on the diagram.

[xviper]

A picture tells a thousand words... (e.g. this one from the manual of the very similar HobbyEagle A3S3 Gyro is very clear)

I thought about that diagram myself but there's one potential anomaly ..................................... Notice how the gain (G) pin on the gyro is fed by the black (dark) wire of the 3 wire lead? Then it goes (single wire) to the "master gain" port at the RX. (The HE and E-52 gyro uses a 3-wire lead than ends in 3 separate single wires with their own plugs. A private individual would use a standard 3-wire to 3-wire female/female extension.) Those who have "polarity" on the brain will then plug that end with the single black wire to "ground", in which case, it WON'T work. That black lead must go to the "signal" pin on the RX port. Plus, on the B-2, if a person used a 3-wire lead, it may be necessary to either pull out the other two ends in the plug or clip the other two wires to prevent any signal interference because the RX will send power through the middle wire and the remaining wire is grounded.

[osuzoo08]

I didn't like the fiddling with rulers while setting up the control surfaces, so two gauges were created and printed. +/- 25mm for the rudders, 8mm Up trim for the inboard control surfaces measured at wing bottom. In case someone is interested in the STL files, I'll put them on cults3d. Just let me know.

I would love if you posted those

[ridgerunner]

... 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.

A picture tells a thousand words... (e.g. this one from the manual of the very similar HobbyEagle A3S3 Gyro is very clear)

[GliderGuy]

Potential “upgrade” offering…the “mains for grass operations” which could be offered on the MRC webpage. Would be handy to have.

Radar-Guy / Great idea - measuring tools

-GG

[kallend]

I didn't like the fiddling with rulers while setting up the control surfaces, so two gauges were created and printed. +/- 25mm for the rudders, 8mm Up trim for the inboard control surfaces measured at wing bottom. In case someone is interested in the STL files, I'll put them on cults3d. Just let me know.

Nice idea. A pity Freewing didn't include something like this in the kit.

[RudyD54]

I didn't like the fiddling with rulers while setting up the control surfaces, so two gauges were created and printed. +/- 25mm for the rudders, 8mm Up trim for the inboard control surfaces measured at wing bottom. In case someone is interested in the STL files, I'll put them on cults3d. Just let me know.

Love the idea. I’d be interested if you post them.

[Radar-Guy]

I asked Danny about his grass field. He is in Georgia and they have hard red clay under the grass. My field is on top of an old land fill and the ground is very sandy. His plane took off with ease, whereas mine bogged down and would not reach VR. So, grass ops are possible, but it really depends on the ground underneath the grass, not just the type of grass itself.

Thanks, Pat. You‘re right.
First mod is taking shape. Single FW T-45 main wheel (60mm) plus a „Frankenstrut“ (T-45 V2 Upper section plus Stinger lower section). Gear door is not entirely closing (2mm), but that‘s an easy fix for later.

[Icarus the 2nd]

I asked Danny about his grass field. He is in Georgia and they have hard red clay under the grass. My field is on top of an old land fill and the ground is very sandy. He plane took off with ease, whereas mine bogged down and would not reach VR. So, grass ops are possible, but it really depends on the ground underneath the grass, not just the type of grass itself.

good info Pat, thanks a lot

my belgian grass is a lot like Radar-Guy's rwy

[crxmanpat]

Some other member of the group pointed me to this. It‘s all about „your grass“.

https://www.facebook.com/842573663/v...80807000491629

I asked Danny about his grass field. He is in Georgia and they have hard red clay under the grass. My field is on top of an old land fill and the ground is very sandy. His plane took off with ease, whereas mine bogged down and would not reach VR. So, grass ops are possible, but it really depends on the ground underneath the grass, not just the type of grass itself.

[Icarus the 2nd]

100A feels a bit low for twin 70mm? You could probably get a bit more out of it by bumping up the timing of the ESCs. Given the intended flight envelope it would only really be used in TOGA scenarios.

it has the power setup of the PJ-50 and 2 x 60A ESCs, 100-105A numbers are normal

[mshagg]

100A feels a bit low for twin 70mm? You could probably get a bit more out of it by bumping up the timing of the ESCs. Given the intended flight envelope it would only really be used in TOGA scenarios.

[Radar-Guy]

I didn't like the fiddling with rulers while setting up the control surfaces, so two gauges were created and printed. +/- 25mm for the rudders, 8mm Up trim for the inboard control surfaces measured at wing bottom. In case someone is interested in the STL files, I'll put them on cults3d. Just let me know.

[kallend]

B. On Spectrum, the rotary switch should NEVER be used for gains. .

Rubbish.

[kallend]

Thanks for the endorsement. I didn’t respond to Aros’s request because he asked for you directly. These single wire leads first came to my attention when I started installing Return To Home devices like the Bigaole. I thought it was peculiar that wire colors didn’t coincide with “polarity” but I followed the instructions and it all worked. Then comes along HobbyEagle’s newer gyros and they did the same thing. Now, we see Freewing’s new gyro is the very same. I only caution people about polarity now IF it involves servos. I think the industry should have standardized the wire color for these gyro applications by making them white or white with stripes.

All white would make it hard to identify which wire is which in the mess of wires that seem to inhabit my models. White with different colored stripes for the different functions would be OK. Personally I have never had any trouble with the current scheme and I have a bunch of HE gyros. But then I am a compulsive reader of manuals.

[Radar-Guy]

That video clearly showed (at least to me) that the ground speed on the grass was very robust compared to the failed take off videos. All grass fields are not created equal OR could it be that the power was down in those planes that failed to “launch”? Were the throttles calibrated properly? Wherwas the throttle trim? Unless told otherwise by the plane’s manual, I put the trim as far down as it’ll go before calibrating, thereby getting a little extra throttle “expansion” (I don’t know what else to call it). Did those people try to increase the throttle travel at the top end, maybe to 110% or 120%? I can’t say if that would have made any difference - just grasping at straws. Consider HV LiPos? I just got a couple to experiment with to see if any given jet will produce just a little more punch.

I used a well maintained battery, IR values in the 4,x range. Both ESCs were calibrated individually. Onboard telemetry (real time display on TX) showed peak value of slightly above 100 A.The Amp draw stabilised at around 90 A, no unusual sag of Voltage. That‘s close to 500W per kg and should be enough.
I will mount larger wheels (single ones on mains) and check how much that will reduce drag. If that improves speed during the T/O run, I‘ll look into the AoA aspect.

[xviper]

Some other member of the group pointed me to this. It‘s all about „your grass“.

https://www.facebook.com/842573663/v...80807000491629

That video clearly showed (at least to me) that the ground speed on the grass was very robust compared to the failed take off videos. All grass fields are not created equal OR could it be that the power was down in those planes that failed to “launch”? Were the throttles calibrated properly? Where was the throttle trim? Unless told otherwise by the plane’s manual, I put the trim as far down as it’ll go before calibrating, thereby getting a little extra throttle “expansion” (I don’t know what else to call it). Did those people try to increase the throttle travel at the top end, maybe to 110% or 120%? I can’t say if that would have made any difference - just grasping at straws. Consider HV LiPos? I just got a couple to experiment with to see if any given jet will produce just a little more punch.

[xviper]

I found Xviper's wording really good:

Remember the confusion with those colored single wire leads when connecting stuff to the gyro? Regardless of color, those single wires are ALL "signal" wires. They go into the signal pin of those 3-pin ports. This is the same for the master gain lead. You hook up ONLY the "gain" pin on the gyro to the signal pin on the empty RX port. In this instance, stop thinking in terms of "polarity". Forget about the color of the wire. Also, the other pins on the "gain" port of the gyro are for something else. They are NOT power and ground pins. If all you're doing is using the master gain, eliminate the other two wires. It has become obvious that some folks haven't gotten this concept and "It doesn't work".

Thanks for the endorsement. I didn’t respond to Aros’s request because he asked for you directly. These single wire leads first came to my attention when I started installing Return To Home devices like the Bigaole. I thought it was peculiar that wire colors didn’t coincide with “polarity” but I followed the instructions and it all worked. Then comes along HobbyEagle’s newer gyros and they did the same thing. Now, we see Freewing’s new gyro is the very same. I only caution people about polarity now IF it involves servos. I think the industry should have standardized the wire color for these gyro applications by making them white or white with stripes.

[Radar-Guy]

Some other member of the group pointed me to this. It‘s all about „your grass“.

https://www.facebook.com/842573663/videos/pcb.1172717290209850/480807000491629