The flying monkeys got me...

Helis and fixed wing

AMA 957918
IRCHA 4345
AMA Intro Pilot Instructor

Tuesday, December 29, 2015

30cc MXS-R Tail Wheel Up


After having her tail gear roughed up and torn partly off on the crappy clumpy grass, I ordered a replacement carbon fiber laminate one from HK (couldn't find it elsewhere). It arrived yesterday, trimmed it and installed it this evening

Snow and winter weather have arrived, so flying is curtrailed for the near future.

Tuesday, December 22, 2015

30cc is up, and the 10cc got her legs back.




I finished up the repairs on the 10cc and she's as good as new with her main gear back in place. I put a 13x8 prop on, instead of the 14x8. I wonder if it will improve her vertical climb if she gets more RPMs. I doubt it, but until I can get a 14x6 its what I have.






I also took apart the carb on the 30cc. I found that the metering valve gasket, the one with the metal wheel hanging in the middle, was upside down and the metal wheel was on the air side, not the needle side where it pushes the needle valve. It was upside down but worked for months. Huh. Not sure it was the problem because it was working, but I flipped it and cleaned the carb. I didn't find anything stuck, but she started right up when I put her back together, so I fixed something. I ran her to dry tank so she can stay unclogged.

I noticed that the tail wheel on the 30cc has taken a beating with the crappy clumpy grass, and was getting loose in its bracket. The bracket is carbon fiber and its delaminated at the hole where the wheel strut comes through. I just ordered a replacement from Hobby King.



I don't expect to be able to fly for the rest of the week, so, Happy Holidays!

Monday, December 21, 2015

Heli "Spin of Death"


When installing a gyro, always, always, always, walk through each programming step like it matters, or you will blow past NORMAL-REVERSE, and on starting your spin up will instantly experience the 960 degree Spin of Death (less if you have good reflexes and nail the Hold). And if you are testing on knobby asphalt this happens as an extra prize.

Sunday, December 20, 2015

Breaking Wind


It was a weird wind day. It wasn't at all what the weather forecasters thought it would be, other than clear. It was a beautiful cold day, and the winds would be dead for the most part, but then a gust would slam in at 20 mph. They were mostly coming from one direction, but then started shifting. I would take off in one condition, and fly through several others, then land in another. It was mostly calm, so it was a tease.




I haven't flown the 30cc in a couple of months, so it really was no surprise I couldn't get her started. I even tried the electric starter. I have no doubt the carb is clogged... Yay... another project. She would have handled the winds fine.

So, I decided to fly and took my 10cc Sukhoi up! It was fun, a few pucker moments, and in the end I made a mistake and ended up tearing the landing gear off. All of them. Meh, easy repair, and a chance to fix a few things.




Tossed her around a lot despite the winds, which were fast aloft. A couple of times it was all she could do to make any ground speed.




The smaller tail wheel got yanked off. I built up the attachment point, used a bigger wheel, and bigger screws with some epoxy on the base of the mount.



All done up.



As designed the landing gear hard point pulled out. I reinstalled it.  The cote in front was torn and a bit worn by gas, so I removed it, gas proofed (using epoxy diluted with alcohol) the wood, and in a few days will recote it, install the landing gear, and get her airborne again!

After I finish this, I will work on the 30cc.


Monday, December 14, 2015

FAA Mandates Registration of All Model Aircraft

In a ridiculous move, the FAA today produced a ruling requiring the registration of all remotely piloted aircraft 0.55 lbs to 55 lbs starting on December 21, 2015.

See the AMA notice here.

Sunday, December 13, 2015

Skyline Sukhoi SU-26 70 Sized 10cc Gasser Successful Maiden!



Today was a dreary cold, albeit ill-temperate December day in New Hampshire. Cloudy skies, winds ~0-6 mph with steady gusts to 10 mph consistently and predictably from the north. The field runs north to south, so this worked nicely. 50 degrees (norm is in the 30's with snow by now) but after a while your hands get frosty. Its mostly tall clumpy grass torn up by the kids who play soccer and lacrosse on it (its laid out I think as 4 fields side by side), with parts at the north launch end more mud and less grass, so I launch there. A good day to maiden. I was quite anxious to do and not do this maiden. I spent a lot of time on her.

This was a longer ARF build than most. I worked for over a month and a half just to get the RCGF 10cc engine running, only to find out a quick manual choke of the carb was all she wanted to get started. Now she starts and runs like a champ. I learned a lot about this engine in that process, and learned a lot about how good the service was from RCGF-USA. Today we would see how the engine flies.

This Skyline Sukhoi SU-26 70 from General Hobby came in heavy for the airframe. Its an electric/glow 70 sized that I built with a 10cc gas engine on a 14x8 prop. Its technically a bit more engine for this plane. Performance wise, despite coming in at around 9-10 lbs dry (I need to re-weigh her, but that's what she weighed this morning), she flies fine and fast. The only thing I lose is unlimited vertical: she will climb but loses her grip and can't sustain unlimited vertical. I had been using a 13x8 in setup. I think I would lose thrust if I went back to the 13x7 because the max RPM didn't change much. Maybe I should track down the recommended 14x7? What do you think? With the 14x8 I get an idle around 2000-2300 rpm, and max around 7200 rpm.  In flight she behaved a lot like she did on the ground tests. She idles nicely, no 4-cycling. She goes from Idle to Max throttle clean, comes back quick from 7200 to 3500 rpm, then slowly to 2300 rpm with visits to 1900-2000 rpm. On quick increase from idle to 50%, which comes out around 6300 rpm, pretty close to max, she will jump but then slowly increase rpm. This did not affect my sport flying today (I don't 3D...). I am considering a throttle curve with 50% around 4000 rpm, but this won't change her max performance of course.  The right side of the fuse got a lot less oil, but the landing strut was still coated. Minor annoyance.

Here's the vid from today's flight. I had to clip the phone camera to my jacket, so what you get is what I got. I do run on a bit with the filming, but I love the clean sound this engine makes. The first part is the maiden. I had run her for a few minutes to warm her up, topped off the fuel, and restarted. As you know I had starting issues, but now she starts right away.




This plane flies sweet, as did her sister before her whom I flew as an electric. That was the red Honda one. On higher rates she is wicked responsive and quick. I had to dial down the low DR on the elevator to 25% and increase the expo to 45% on all the rates. Now I have found her sweet spot and she is a pleasure to fly. I need more landings to get her feel, and after this flight I put bigger wheels on her to see if I can keep the prop spinning on rollouts.



The difference from 2.5" to 3" may not look like much, but it usually makes a big difference in the tall grass, and lifts the prop nicely out of the cabbage. I had thought about going with the larger wheel when I first installed them, but was too lazy to remove them from the large axles they were stuck on. Today I unstuck those bigger wheels (subtitled: Vice Grip Always Wins).

Wanted to keep flying, but I was starting to get cold. Looking forward to my next flights!

Saturday, December 12, 2015

Sukhoi SU-26 RCGF 10cc CG

I CG'd the Sukhoi today. It took a couple of oz in the tail, and I left her a shade nose heavy. I took an unweighed chunk of epoxied lead and set her in the tail. Surprised me that it was exactly the amount I needed. I epoxied it in and then created a couple of bridging spars to make sure it stays put.

Plan to maiden tomorrow!



Thursday, December 10, 2015

RCGF 10cc Run-Ups

Ohhhh, I do LOVE this engine!

I put the cowl on today having changed the prop to a 14x8 (Joe Nelson of RCGF-USA recommended a 14x 6 or 7, but when I stopped by RC Buyer's Warehouse in nearby Nashua, NH, they were NIS, so I went with the in stock 14x8 Xoar. I didn't think to pick up a bigger spinner while I was there, and ended up ordering one from them, a 3", and got it a day and a half later, today!

Listen to this engine purr... with the cowl on she is almost quiet!  She does spit oil with the 30:1 mix, just a bit of oil clean up on the left underside wing and landing gear. I really didn't need to change the needle valve settings going from the 13x8 to the 14er.




I show her running my three standard run-ups. Running time at 50% on the Spektrum gimble, where she ran in the 6000's rpm, after about 20 minutes on a 240cc tank she slowed to a stop. I like to fly for 10 min, so this is a nice bingo. With the bigger prop she idled around 2300 rpm, any lower and she would quit. She produces very little if any thrust at this rpm. At full she gets up to 7100-7200 rpm and produces a very, very nice thrust. The second test is Idle to Full throttle. She comes up nicely to full and drops back to idle smoothly, taking a few seconds to drop the last few hundred rpms. The last test is Idle to 50%. She responds from idle to 4000's but then slowly climbs up to the 6000's. This lag isn't seen in going from Idle to full throttle, which is more important to me.

I am excited to be putting the RCGF 10cc engine in the Spitfire build this winter!

Wednesday, December 9, 2015

Monday, December 7, 2015

10cc Sukhoi Cowl On!

It took an absurd amount of work to get the cowl on. I had fitted it to get the length for the engine weeks ago, but once I had everything under the cowl the fitting work began. I had to flip the ignition upside down so it hangs partly down into the fuse, then I had to Dremel down openings to get the spark plug and muffler to clear. In the end the holes are a little bigger than planned. But judge for yourself, she looks sweet!  I think she needs a black prop though!







RCGF 10cc Happy Happy Joy Joy!!

I have been sharing the troubles I have had getting this simple RCGF 10cc engine to work. It got to a point that everything had been checked, checked three more times, rebuilt, and yet no one could figure this out. My latest failure was a downer, as there was nothing left to do.

I never lost hope because of the personal attention and guidance I got from Joe Nelson of RCGF-USA by phone and email. This not starting made no sense. He reviewed the Electric and Fuel video and he could find nothing wrong. He responded to my last email never giving up, and we went back to what we knew: too much or no fuel?  I knew it wasn't flooding. This was an obvious question given starting the engine with an electric starter, and several times I had checked the spark plug and it was dry. This left not getting fuel.

Again, no sense. I could see fuel getting to the carb. Joe wondered if it wasn't actually getting in, and suggested I try choking the engine. This one doesn't come with a choke, generally is small enough it doesn't need one. So he suggested putting my finger over the air inlet and choke starting it. As soon as I read the email I was out in the garage, my finger over the inlet, and putting the starter to the spinner...




Now that its running, I ran it, stopped it, started it, over and over and she just get working like there had never been anything wrong! I think its time to put the cowl on!

I have two of these engines. As you may recall, Joe sent me a brand new engine and told me to keep the first one as he had discharged it as non-functional. I plan on putting that engine in the Spitfire I will be building this winter. If she runs, I will pay him for this one too, discharged or not!

If things continue to go this well, and I can get my engines from Joe, RCGF is now my engine maker.

RCGF 10cc Electrical and Fuel Setup

As I work on trying to get the newer RCGF 10cc engine running, I am sharing my setup for comments and ideas on what might be going wrong with it, why I can't get either engine to run.

UPDATE: She runs! Turns out it was something simple.

Please watch it, and comment! The first half is electrical, middle shows proof of spark, then fuel system, and the last part is all the stills you need to see the engine and setup.


Wednesday, November 25, 2015

Twinstar maiden goes perfectly!


The 4S, I learned, is a little tall for the hatch, so a piece of Velcro as tape holds it on. As an experienced builder ya think I would have test fit the battery before I left the shop...


Early afternoon, cold breeze from the south, sun
low on winter horizon standing unfetteringly bright just a few degrees above the southwest tree line.

The fall grass is thick and clumpy, but there are parts where its almost mud. I carry the Twinstar over to one of these barrens and face her south, down field. Check control surfaces, check flaps, check full power run up. Look, listen, feel. First flight. Be a good girl.

It's time. Full throttle, and she fights her way down the runway, such as it is, and as she clears the grasping grass and gains speed, the powerful torque of twin props rolls her to starboard. I easily correct and take her into a right climbing turn to clear the western tree line, avoiding the sun line. She gains altitude too easily. Nose down trim, a bit of left aileron trim, a tweak here and there, and in a few passes she is trimmed out despite a choppy wind aloft.

The power setup is spot on. The 4S nestled in nicely and she is balanced now. She won't go vertical, but she is aerobatic. In fact, my low aileron settings are too high for even high settings, and I had the low rate tuned to about 35%!

I try to slow her for a landing approach, a long one, but even with 50% flaps she is fast on the final. I need the higher aileron throws at approach speeds with the flaperons down. She descends nicely, predictably, but fast. Several landings and approaches, its just the way she is. And she puts her nose down when those back wheels touch the thick cabbage, and she buries her nose wheel and abruptly stops, stuck where she came to rest. It's a walk in taxi almost everytime.

A couple of times I manage to find a muddier less grassy spot and she rolls out. But her props are green with grass she had cut and thrown into her wings, and the green slaughter coats her props, belly and nacelles.

I fly two or three packs, at 10 min a piece I have already forgotten. She was quite an easy flier.

I had brought the 30cc gasser, but even after this fine flight set, I really am not in the mood, so we pack up and head home.

Flying is better with friends, but no one is home, so I fly alone, and thus my stay is brief.

It was a great maiden, good design, good build, good engineering.


Nose wheel is bent back by the grass.

Preflighting the Twinstar

Preflight testing of the Twinstar this morning, planning on a maiden today after some Honey-do's.
She has Sky Power 40A ESCs. The 480 Plus motors are rated for max 450 watts, but they caution running more than 400 watts sustained. I am running a switching voltage regulator instead of the BECs.

Ran the motors using the 3S 2200 mAh. I got about 7 min, 350 peak watts, around 35 peak amps. On the 4S 3300 mAh it peaks at over 700 watts, 37 amps! On time testing I got 15 min with some cells dipping to 3.4 V.

I need that flight time, so I set up a throttle curve and at a top curve endpoint of 50% produced around 430 watts, around 27 amps. At 50% of that throttle curve it produced around 230 watts and 12 amps, and gave me that 15 min runtime. The 3S 2650 mAh gave me about 10 solid min before.

So I plan to fly her 4S 3300 mAh set at 10 min with 5 min bingo, using a throttle curve to bring the power down so I don't blow the motors. I can fly the 3S 2650 mAh if necessary but would need to remember to remove the throttle curve. Not likely to do that.
More on the maiden later today!

Tuesday, November 24, 2015

Great Planes Twinstar EP Ready to Maiden!

Well, that's embarrassing... So I am watching the cat play with a white piece of plastic down in my shop... Wait a minute. Let me see that. Sonofabitch. It's the plastic Nose Gear bracket thingy. (Apologies to Great Planes...).

So I installed the nose gear and the nose cone, on the Twinstar EP, put a fresh 3S 2200 mAh battery in, checked CG (fine), and ran the motors at 50%.  Got almost 7 min, but it took them down to 3.5V. I need to see how it does with a 2650 mAh, or I will need to get the recommended 3800 mAh.



Trimmed that...



 






Bench test. Power to spare.  50% Throttle, 3S 2200 mAh, got close to 7 min but went down to 3.5V/cell.




I find their lack of faith... disturbing.





But for a nose block, the Twinstar is done.

The motor mount arrived from HeadsUpRC today, allowing me to complete the install of the port side motor and nacelle. All that is missing now, on The Plane of Missing Parts, is the nose wheel block, coming from Great Planes/Tower Hobbies. Once that is in, she will be complete within a few minutes, ready to CG and maiden.

After installing the port motor I ran them on a 3S briefly. Plenty of voltage/power. I wiIl need to see how much time I get on fresh 2200mAh. I am looking for 7-10 min of sport flying. I believe she is rated for a 5000 mAh or something ginormous. I already have a lot of connectors and adapters in there adding weight, but could easily change the EC3 one I have to EC5 and series in a pair of 2650 mAhs.



Saturday, November 21, 2015

Thursday, November 19, 2015

The Plane of Missing Parts

Does twice make a trend?

As my Great Planes Twinstar project has unwound I found I was missing a motor mount, now graciously on its way from HeadsUp RC, and today I found that the Nose Wheel Block, the white nylon part that secures the nose gear to the airframe, is also missing. I keep all the bags and boxes, checked, not there. I went through the trash, not there. I crawled around on my knees and belly looking on the floor and under the work benches, not there. I called Great Planes/Tower Hobbies and a replacement is on its way.

UPDATE:  They never sent me the part, which is okay because I found the missing one. Cat stole it. No, seriously.



Between these minor annoyances and the problems I had with the RCGF 10cc engine, I wonder if I need to tune my RC mojo.

I finished the wings, but for the left motor for want of the mount.





And installed the rudder/steering servo, and the elevator servo.



And finally the tail.




I am stopping here for today. Next time installing the control rods for the empennage and steering, the latter once the nose wheel block arrives. Looks like another week before she will be flight ready.

In the meantime I await the RCGF 10cc.

Tuesday, November 17, 2015

Eflite Stearman Maiden

Beautiful day, virtually windless. Perfect time to take the Eflite Stearman up for her maiden flight. The takeoff and first flight was hairy. Despite being on CG she flew a tad tail heavy, her DR and Expo were off (too low), and it took some sick skills to get her back down.

Over a couple of flights I found her happy place, she rolls like a pig, buy otherwise handles predictably. I enjoyed the flights and flew three long 3S 2650 mAh packs.






Saturday, November 14, 2015

RCGF 10cc Update: Try, try again.

UPDATE: Its running fine!  Read the UPDATE.

At my last posting on the RCGF 10cc engine with an update, I was having the ups and downs of our hobby, trying to get a new engine to run. If it wasn't for the exceptional one-on-one service from Joe Nelson at RCFG-USA, I would have abandoned this long ago. After this, Joe and I are going to be drinking buddies! I haven't had such personal attention from a dealer, someone who is more disappointed about this than I am.

So... this morning I ran out to RC Buyers Warehouse in Nashua (if they don't have it, you don't need it), and picked up a Hanger 9 Power Pro HD Starter. I McGyvered an EC5 connection to the alligators on the starter and ran it off a pair of 3S 2650 mAh Lipos in series (~24V).  I used this to try to start the RCGF 10cc (more on that in a moment). I didn't mean to run it in series,but I fogot I didn't have a parallel cable and used the series thinking it was a parallel cable...  Since it worked well, I decided to unsolder the gators and installed an EC5. This evening I made up a series connector and tested it at ~12V 5300 mAh. Runs fine.







Now about the engine. I used the starter this morning, and I could not get the engine to start. I ran some experiments that showed that the vacuum was sufficient to feed the pump and fuel was coming out of it just fine. It was filling the pump outlet line to the carb; fuel was getting to the carb. Was wasn't it starting? Check spark, all fine. I decided to remove the engine and check the carb. I tried blowing in the inlet with the throttle open, and I couldn't. Don't know if I should be able to with the needle valve not being metered. I took it apart and removed the needle valve, used Gumout to clean it. With the needle valve removed I could blow through it fine. I put it all together and tried running it again, still no joy.

Joe Nelson (RCGF-USA) and I chatted and he got some calls with issues like mine, and spoke to some skilled pilots, and he realized that those of us having problems weren't using starters. As we thought, hand starting didn't develop enough vacuum. With the starter it clearly moved the fuel. The other guy who used a starter once he was told to had his start the first time, his problem solved. I have no doubt I needed the starter, but is there something wrong with this motor? Why? Joe got it running before he sent it back.  I am out of ideas.

Well Joe has a new engine coming to me with a return label for this one. He's going to see if he can get it running. I've uninstalled the engine and ignition, cleaned it and packed it to return, waiting for the new one.

I hope there isn't something wrong with me and my setup. We'll know if I can't get this one running.

I am optimistic the engine will be fine. I am not optimistic that I can get it running...


Sullivan Skylite 4" From Hobbylinc

I needed to go to a 4" tire on the 30cc MXS-R to keep the prop from touching on roll-out, mostly a problem on landing in the thick grass at Joppa Hill. As she slowed she has a tendency to ass-over-teakettle if she doesn't finish the roll-out in the thinner cabbage. I boosted the gear off the fuse with some spacers, but she still needs a little more.

I picked up a pair of Sullivan Skylite 4" wheels with aluminum hub from Hobbylinc.com.  I unboxed the shipping container and noted the package of one wheel was opened, but didn't care until I realized on opening the closed one that the opened one was missing the screws that secure the hub. I was annoyed, but after rummaging through my stock I found 6 bolts and nylon lock-nuts that would work. Its always something.  They look great!



The one that was opened was opened along the top only, this is after I removed the plastic.