Finished at last!  Sunday, God willing will be it's second pattern and first official!  Nothing like practice to make for high scores.  Hell, if you place last you still placed!  I may get out tomorrow to test the change in prop rotation.  Fixed the misplaced "4" on the logo.  Pray for light winds, 5-10.  I may just surprise everyone.

Ken

Well the surprise was on me.  Need to switch ESC's and go to 6s batteries.  Today took 4013 out of 4200 and it started to lag in the hourglass.  I cut it short, free flighted through the overhead eight and did an itty-bitty cloverleaf just so I could say I flew the entire pattern. See for yourself if you need a good laugh:



The plane flies like nothing I have ever owned.  Like it is on rails.  I will have to adjust to how tight it can corner. Couple more flights will fix that.  Someone forgot to tell the camera man not to follow the plane in the OH8.  It really wasn't that bad!

Now for the "how can I save battery".  I am running 10,020 RPM on both motors with BadAss 10x6 props.  No vibration I can hear.  I cannot hear any boost anywhere in the pattern from the center.  I am sure I am getting very little overhead.  I have been told that I could run a lower pitch and higher RPM and save battery.  I was thinking 10,200 and a 10x5 prop.  I am also going to cut the elevator fences from 1/8" to 1/16"

If that gets me enough to be able to do a full sized clover  I will fly it Sunday.   

After a bit of watching the video I did some lap time checks.  Level flight after takeoff 5.4 (Heaven), Inverted 5.3 (Close, sensor a bit off) and level after pattern 5.7.  That one needs to be around 5.5.

The BadAss charts tell me that my maximum continuous power fir the 2 2320's is 930 Watts.  The 3515 that was going in the nose before I turned it into a twin was 1200 Watts.  The plane weighs the same as Endgame III at 70oz which easily completed a pattern on a 6s 2800.  I am baffled why I need 4000.

Ken                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               

I wasn't able to solve the battery issue before the Gieseke which is sad.  It was to be the planes "Debutant Ball".  Another one in the fall.  I need help finding a 6s >=30A ESC with BEC that is as close in width as the Jeti Spin 33 Pro.  23cm if the specs are right.  I can probably go 25 without having to redesign the nose.  Any help will help.

Ken

Update - A new member of our flying group is also an avid RC flier.  He introduced us to the racing drone ESC's he is using successfully for control line.  I just ordered two Flycolor 40A 6S ESCs that are both shorter and narrower than the Spin 33.  According to him they have a very fast response time.  We will see!

Two brand new FlyColor 50A 6S ESC's.  Saved a couple of ounces.  They have a very distinct test run which is nearly immediate after starting the timer.  Get a half speed 1 second burst on both motors.  Now I have no choice but to move the timer...yuck.  I pray the 6s 10-5 combo works. 

Sometimes electric really sucks but not often.

Ken

First flight with the FlyColor 50's.  Worked great with 2 exceptions.  I have to figure our how to change the spin-up from 100% and the low voltage cutoff to 2.8.  It appears that the changes to the APC prop and general airflow cleanup has made the current motors and battery workable.  I will know more tomorrow.

After the last session I did some video tracing of the corners in slow motion and Mark Wood who was with me at the time noticed the affect of the canard and after some geometry he recommended that I double the movement.  I made it fully adjustable on IV so I made the change.  I know it sounds crazy but it now "flies" around corners like they were itty bitty round loop segments.

That was the whole reason for the two year, so far, experiment with the canard.  The attached is how the canard (green) looks in a frame-by-frame playback of a corner.  The blue and red show how everything else looks depending on how your flap ratio, CG, etc.  I know to most of you that this is a big "so what".  Corners are good enough, but are they?  Tight enough, yes.  I would say that they are approaching 8' at the top but they look forced.  To me, the satisfaction of seeing my plane fly around a corner and exit perfectly flat is worth the effort.  Wait, there is some wind!    I need to go whistle 

Getting this thing contest ready is getting to be a project.  So many things to get into balance compared to a simple plane,  Worth it though.  Just like everyone else finishing #4 is the first step in building #5.  I flew the Trifecta with the twin rudders last week and it reminded me just how much I like them.  So Endgame 5 will have twin rudders!  And some rather out of mainstream flaps.  Artest's rendition attached.

Ken

I can see it now, the name of that beast will be "ComingorGoing".

Steve

Quote from: Steve Berry on August 01, 2025, 05:36:36 PM
I can see it now, the name of that beast will be "ComingorGoing".

Steve

Nope, I am sticking with Endgame 5 - "Hammer Head".  Even Mother Nature knows the value of a Canard!  From Wikipedia - "The shape of the head aids in close-quarters maneuverability and allowing sharp turning movement without losing stability."

Now who would want that?

Only 75,000 more views and I have a cool million!  No wonder I get adds on my video's.

Ken

Reaching a frustration point.  I knew I should have studied electrical engineering in college.  I need some explanation of what a motor should draw.  I have a twin with two BadAss 2320-820 motors, twin FkyColor 50a ESC'e and a Fiorotti timer.  I am using a 6s 2800 35a 25c battery.  Let's forget weight for now because I am doing something wrong with the Prop/Pitch/RPM.  Weight, drag and cooling are all factors but not the core problem.  I suck the battery dry by the time I hit the SQ8.

For comparison I use the same battery on a similar size single 3520-790 and have plenty left after the pattern.  The Watt rating from BadAss is roughly the same for 2 23xx's and 1 35xx.

So this leaves me with several questions:

Will a heavy and a light plane of similar drag require different RPM to maintain level flight.  I would think the heavier one would actually require less.  Is it possible that I am running too high an RPM to get through the maneuvers and as a result the boost overtaxes the battery and I don't get it.  I don't feel or hear any yet it is set fairly high.

Will two 25a max motors overload a 35a battery in a high stress climb like the RWO?

I am running BA 10x5 props.  I have tried APC but they were worse.  I don't have any idea what RPM is appropriate.  The plane flies quite well at a 5.4.  Today they were running 8800 and 9000.  Metered on the ground they were pulling 850 watts.  That same setting gave me a 5.0 takeoff speed.  It was at 5.4 by the end of the squares and 5.7 after the sq8 where I aborted and that was in a 10mph wind!

I once changed the pitch to 10x6 running at around 7000.  That let me get through the pattern on a 5s 4200 battery with noticeable sag starting with the hourglass.

I don't think there is any combination of battery and prop that will give me what I want with these motors.  The question is will going to 2815 size motors help?   I am told that they will use less battery. If amps over taxing the battery is the issue then the 3000mah P30 is 30a which is less than the 2800 P28 at 35.   I may have just built the best flying plane that can't finish a pattern.  There has to be a solution.

Enough rambling - Ken

Up here in the rarefied climes of northern Utah, Page Peterson recently built a big 750" twin with some similar features to yours.  Currently sporting 2 BA 2814/870kv motors and 10x6 BA props.  Newest Igor system. 5s4500 p45b packs that work well.  Read 3.6v or so after full pattern.  Still early in the testing process but it is a really good flying plane already!

Ken,
I put first flights on my new twin profile two weeks ago. It is a copy of my old single motor (3520) profile that is 3 years old and showing significant wear. Weight is just under 73 oz with 6S 2800 28B batteries. I am flying on 70ft lines.

At 5.3 laps with 10x5 BA props, I also had a difficult time with the battery/moto/prop combo. I ran 4 minute flights and the batteries came down very hot (hottest point 170 deg) at 3.53 volts remaining on my battery checker. I checked the amp draw. It was 45 amps on the round. Probably not good long term for the 40 amp continuous battery rating. I decided not to try the new 30Bs I made up for it since they are only 30A.

I switched to 10x6 BA props. They helped reduce heat by 10-15 degrees in 4 minutes flights. There were 3.59v remaining and I put back in 1830 mah. Unfortunately, it is still too hot and at that consumption rate, probably not enough capacity to run 5:15. I do not have the active timer turned on which would increase amps even more in up legs.

I built a couple 45B 5S batteries to try on Friday. They solved the problem. With 5:00 flight at 5.3 laps, they came down with 3.66v remaining and cool. With active turned on it finished at 3.62 and only slightly warm. It did not sag anywhere in the flight. I have not recharged them yet to know how much will be put bak in. I am not excited about adding another 2 ounces to an already heavy plane that in early flights seems like it might fly well.

I will continue to test different batteries, motors, and/or props to see if I can come up with something better that might also be lighter.

My single motor profile also has challenges with capacity/heat with a 3520 motor and the 2800 28B batteries. It can run 5:15 for a contest, but it gets really hot. I practice with it at 4:30 to try not ruining the batteries. I will put the 45Bs in that plane too and switch to a 3515 to keep the weight gain down. If I had some TP 6s2800s, they would probably also work fine with the single motor to remove the higher amp concern.

It has been great to get back flying after hip pain kept me from getting out from mid-April until mid-July. The challenges of getting the twin working has been very enjoyable and got me excited to be back flying. Look forward to flying it next week at the So Cal contest.

Page

Page:  Good to hear from you.  I will post each of my mini-adventures in getting the electrons under control as well.  Are you using one or two batteries?  Part of my problem was the motor wires.  I thought I could get away with 16 gauge on the 2320 can and boy was I wrong.  I was pulling 300 extra watts.  I am refitting with 12 gauge.  It is entirely possible that I can get away with a 6s 3000 pack with the new wires.  If not I am going to build a 5s 4500.

I have the same problem with weight that you do but, I have been working with some engineer types that tell me that 70+ oz is not too heavy for a 710 sq" plane if it has the right airfoil.

I am grounded till September on the twin for contests.  Having to fly my Trifecta Profile.  It is my 1964 design so it qualifies for Profile, Classic and PA.  Easier to fit in the car that way!  I am running it on a BA 3515 using a 6s 2800 (P28B) pack.  I use just over 2000 and it is strong in the clover.  Seems you might have the same.

Ken

Update on the great battery drama.  Last outing I was introduced to something that I should have had years ago.  A Watt meter.  As we (mostly me) were scratching our heads at the field why I could not find a combination that would get me through the pattern with proper power at the end, I was asked what it reads on a meter.  I tried to act as if I knew what he was asking but obviously failed.  He is an old RC type so his flight kit had all kinds of toys that I had never seen.  He hooked up a Watt meter and we fired it up on the ground.   The first picture below was the reaction.  At takeoff RPM I was at 9000 which is about right and I was using 850 Watts.  That is 425 per motor or just about double what it should be.  Multiple skeptics so we did it over with a different battery - same result.

So, I bought a Watt meter and called in Columbo.  We started looking.  First the wires.  Likely source.  I had used 16 gauge since that was what the ESC came with (both the FlyColor 50 and Spin 33 used 16 gauge).  It was stranded copper, not MIL Spec tinned but it turned out to be high enough quality and only resulted in a 10 Watt reduction when replaced by similar length MIL Spec 12 gauge.  Not worth tearing up two wings so I left the 16 gauge motor wires.

Next was the ESC.  The word on the FlyColor was that it used less.  Not so.  When I reran the tests, the Spin used 20Watts less than the SpinColor so it got it's gig back.  The FlyColor never really liked the Fiorotti anyway.  You had to start from a removed safety plug every time and have the progamming switch off or one ESC would arm and the other, well it did sometimes and you got a 1 second full throttle acknowledgmgnt burst....annoying.
Still it worked in the air just fine.

You have to be careful with a twin on the ground.  They get hot quick since there is no airflow over the electronics and battery.

Next up were the connections and I hit Pay Dirt. The battery leads plugged into a set of 12gauge wires through an XT-60 plug and connected to a pair of home made connectors I made from male 3.5mm bullet plug connectors.  That drove both ESC's.  Two bad solder joints on the red wire!  With all of that fixed it was time for testing again.

This time I closed everything up so that it was "ready to fly".  Apparently the resoldered connectors made a difference.  With everything set as it was from the last test the motors cranked up to 10,300 and 10,150 which is a bit above where they were.  660 Watts on two BA 10x5 props.  It took some profanity, but I finally got the timer convinced to run them at 9300 and 9250. 460 Watts!  We were back in flyable status!  One last swap.  The BA 10x5 for a set of APC 10x5's.  444 Watts and it is back to the field to see if it will do a full pattern with a wingover out of the Clover on a calm day.

That's only half of what I found.  The cooling tunnel for the battery was blocked with all kinds of wires and a baffel I added to cool the ESC's.  I added two scoops on the sides just for the battery and two exits in the canard bellcrank hatch.  Now when I use an airgun to blow air in the front I can feel it come out where it is supposed to.

This has been an adventure.  Endgame V is under design, it will still be a Hammerhead.  Only change to the Canard will be a wider adjustment range.  Flaps will be unsealed, larger and with a hinge line about 3/4" from the LE vs the 1/8" on IV.  May use a floating stab.  Jury is out on that one.  Last one hunted so bad the game warden asked for a license but that was before bearings, CF Rods and Ball Links.

Couldn't resist this link.  Has nothing to do with the plane other than it's name.  It is comforting to know that one of the most intelligent sharks has a canard!



Ken

Lesson.  When the plane is flying too slow, suck it up and fly it out.  I am going to borrow a line from Top Gun.  "Your sons are dead because they were stupid."  With everything I did to make Endgame IV work the one thing I forgot was the idiot I chose to trim her.  All of the electronic changes worked, all of the cooling changes worked I just had the rpm set wrong.  After 4 minutes of level flight I did some simple squares and triangles.  So what if I was flying at 6.7, I didn't know that.  There was a 10mph wind and It was fun to do some really slow squares.  So why not a couple of outsides to unwrap the lines.  First one was OK, nice 2' bottoms.  Then the wind stopped but I didn't and now I have a wing in search of a fuselage.  Guess I won't be putting on cornering display Sunday like I planned.  This year, building season just became a*Rebuilding* season.

This is not the end of the canard adventure.  As far as I can tell so far, the canard equipped planes were both more stable and turned better (not necessarily tighter) than anything I have ever designed or flown.  What has been missing is a test bed that will let me find the right moments, areas, and CG.

Good bye old friend - ken

Well, that sucks. Always sad when a good plane meets it end.

You could look at it this way - the stuff that survived the crash could be built a little lighter (ie- overbuilt).

Back to the building table.

Steve

Rats, I hate it when I do that!

Look at all you learned though. When it seems all our hard work just disappeared into a broken pile. The truth is, when one leaves the well-worn trail, you often run into stumps hidden in the weeds, or worse even......

Sorry, but I'm looking for "Hammerhead ll" coming soon to a flying field near you. Nastier. Meaner, and able to rip a pattern to pieces.

John Miller

Quote from: John Miller on August 30, 2025, 02:35:26 PM
Rats, I hate it when I do that!

Look at all you learned though. When it seems all our hard work just disappeared into a broken pile. The truth is, when one leaves the well-worn trail, you often run into stumps hidden in the weeds, or worse even......

Sorry, but I'm looking for "Hammerhead ll" coming soon to a flying field near you. Nastier. Meaner, and able to rip a pattern to pieces.

John Miller

The only parts that were total write-offs were the nose (pilot could not eject) and the nacelles.  The nose needed a redesign and I wanted to move the nacelles out 1/4" to accommodate a 2614-600 pair of motors.  This will put it back in the air more as a development platform to maximize the canard.  I hope to be able to do an article on this adventure someday but not till I can post a video that really shows what it can do.  Hammerhead II, which would be Endgame 5 is going to be 10oz lighter with a higher aspect ratio wing, larger flaps with less movement.

What I did was just plain stupid.  It was dumb enough to do an outside square from 30 degrees flying a 6.7 lap (so they told me) but to do a second one?  If there is a video, I am sure it will surface on the Darwin Awards.

Ken

Looking forward to your path through the brambles my friend.

John M.

Since we don't have a rebuild forum I will just add along here.  Careful analysis of the damage has changed my approach.  I am going to repair it "as is" and add a new nose and nacelles.  The back end is pretty light.  162 grams from the end of the flap and it broke off really clean with big jagged edges.  With some interior braces it went back together in perfect alignment!  I will redesign the nose to properly mount the ESC.s and I am lowering the battery 1/4" and eliminating the lower hatch.  Instead the top of the fuselage back past the wing LE will be a huge electronics bay and hatch.  The original started out as a single motor.  Cramming 2 sets of wiring and ESC stuff turned the nose into a blivit. I will add some pix as it progresses.  If it flies as well as before the crash I will strip it of the MonoKote and give it a new set of threads.  For now, no effort to make it pretty.

Ken

Quote from: John Miller on August 30, 2025, 06:45:28 PM
Looking forward to your path through the brambles my friend.

John M.

The Path started with repairing the stab.  Thanks to the Carbon Fiber spar the stab only had some cracked sheeting,  A little coaxing got it realigned and a little CA made it whole.  The Fuselage break was so jagged that it just had to fit back together.  With some bracing, it did just that.  All of the internal doublers in the nose were carbon fiber and none of them broke. The Nacelles were a write-off and I just cut them off.  Brainstorm as to how to fix was deferred until I got the nose rebuilt.  Nice part is that I learned from Endgame II how to make a nose that was not glued to the plane.  I was able to rework the wiring so that I didn't have the spaghetti farm I had.

Rebuild nearly completed.  I am replacing the nacelles with slightly larger ones that will house a 28xx motors if the 23xx just doesn't hack it. Looks like weight will be similar.  Flying the Trifecta to keep the muscles from forgetting.

Ken

Two bran new Tempest 2820-810 motors arrived Thursday.  All the work remaking the nacelles so that they could accommodate a 2320 or 2820 motor was not wasted, only most of it.  The mount fit but I could not get the motor in position to slide into the nacelle like it did on the drawings.  So out comes the #11 and we now have a removable hatch.  So far I am not impressed with the Tempest but reviews are good and it fits perfectly.  Just looks cheap and the power leads are pretty small.  I will crop them as short as possible.  Still waiting on the timer.  I left the Fiorotti programming switch in just in case the Climb and Dive timer doesn't get here in time.  I think I could have built a new plane faster than repairing this one.  I have tried to save weight but I suspect it is going to get the Mrs. Piggy decal.

Ken

Even a rebuilt test bed needs new digs for the pilot!

Ken

Nearing Completion!

Looking good. Should fly as good as, or better than, before.

Steve