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Posted by mechmove | Sep 04, 2021 @ 11:39 PM | 25,570 Views
I had the servos and motor installed by an experienced builder, this is my first attempt at CG. Looks like lots of nose weight required, or better yet maybe a larger battery. Was planning on using my 3s 1.3aH tp pack, but too light. This is turning out to be a lot heavier than I wished for. Currently at 57 ounces with out battery.

Also, look closely at the tail, it’s slightly lopsided with respect to the wing, it may be difficult to notice in the photo, but its quite apparent . The elevator hinge came glued to the tail boom. I wouldn’t have expected this.
Posted by mechmove | Sep 03, 2021 @ 09:59 AM | 26,633 Views
I am not compensated for this!

29 USD, plus a section of old PVC pipe, plus three dollars worth of pipe insulation from Home Depot. Handling my planes is so much easier with this small investment!
Posted by mechmove | Aug 26, 2021 @ 08:39 AM | 12,461 Views
They fit in my Prius, but why not upgrade them to First Class? Last day with the Yukon, so much easier to load my planes. The irony, no one complains when I drive this car slow.
Posted by mechmove | Aug 25, 2021 @ 11:09 PM | 9,827 Views
This morning, I departed for Long Beach in my rented GMC Yukon. This SUV is very comfortable for long drives. I feel as if I am arriving into Long beach as VIP. I never felt like that in my Prius, its a struggle to drive that far, although the gas mileage is very good, I usually arrive tired and a little beat up.

Big SUVs... I get it.

When I arrived, the flying pilots, an experienced DLG guy and (2) competition grade pilots flying electrics. I always get a kick out of talking shop with fellow pilots. I managed to do some flying with my Alpha, but spent most of the time talking and learning. The DLG pilot gave me some good hints on DLG repair. Wet paper towel and a hot covering iron to remove kinks and creases. Works like a charm. Also an added benefit, it helps to cure CA to its maximum strength, and he confirmed the BCH DLG can accept foam-safe CA. Since I keep the CA in a refrigerator, it never cures on its own. The heat acts as a kicker. The CA was used to join the broken bits, and tighten up spots of delamination as a result of impact. I decided to reinforce the broken area post-repair with thin clear tape to smooth it out even more. The final result is rock solid, not perfect or pretty by any means, but I am ready to throw again tomorrow morning.

Looking forward for my final commute in the Yukon, I might have to sell my Prius and get into something that is more comfortable for longer drives.
Posted by mechmove | Aug 24, 2021 @ 08:40 PM | 13,956 Views
This morning, I arrived at Long Beach around 9:45am, unpacked my Alpha 2m and sun screened up. Two pilots out in the field, one DLG and an electric polyhedral (I found out this one was built from a kit made in America). Both were climbing like crazy, the DLG was probably higher than the electric! I launched and found plenty of unstable rising air. I had to employ steep wide turns several times to avoid busting the 400ft altitude restriction. Had a nice conversation with the electric pilot. He has a glider and ppl rating, also teaches instrument flying. The glider is a kit made in Arizona. You assemble and cover it. The fully built ship flys great.

After completing flying, my plan was to go out to eat, then return to the park to fly my Supra. I found a Mexican place with lots of good ratings, “Str8 Up Tacos” in Lakewood. If you come out to Long Beach to fly, there is chance you might hit this place up. I highly recommend the food, BUT be careful driving into the parking lot!

I ended up driving up the curb and destroying my front tire and rim. Est. a day in the shop. I wonder how I might have misjudged it, but others who heard the accident told me it happens all the time. There is an optical illusion, the opening for the driveway appears to be where it is not. The actual opening is off to the side. I witnessed another driver do the same thing 20 minutes later, but her car survived. While the car is in repair, I took the opportunity to rent a GMC Yukon, my accident car is a Prius C. I feel as if I am living in the lap of luxury, powerful AC, my 2 planes fit in the car with no issues, room for a lot more. Plus a comfortable and easy commute to Long Beach. And I sit higher than everyone else in traffic. Too bad for the gas mileage.

I will continue enjoying my time off, can’t let these things take you down.

Thanks for reading.
Posted by mechmove | Aug 24, 2021 @ 09:20 AM | 15,931 Views
Yesterday, I did notice several real aircraft flying low over the field. Going to sky vector, the TAC chart does not have this field mapped. This means the VFR pilot flying into Long Beach will not be aware of radio control aircraft below 400 feet. Since these planes are landing at Long Beach, they are allowed to go even lower! I do not know if these pilots are given a warning by the tower they’re about to cross a radio control field. Since we are allowed up to 400 feet, the TAC chart should have a warning not go any lower when landing at Long Beach. Next time I will have my PCAS MRX to get an idea about how low they actually are.
Posted by mechmove | Aug 24, 2021 @ 09:11 AM | 15,910 Views
Yesterday morning, I went to my local park around 9am to catch the rising sun. The field was nearly empty. I launched a few times, then as the winds from thermal generation picked up, I was able to stay aloft longer. I’ve caught many a thermal with my electrics in the past, but this was different, purely out of my own power. My final launch was downwind for speed, then coming upwind to penetrate any thermals. It worked pretty good, but it ended with the dumbest move I’ve ever made in my flying career, I attempted a downwind landing, and the ship came in faster than anticipated, I ended up jumping over the plane, and I cleared it, but the fin snapped! I bent it back into place, but need to attempt a repair. I was informed by the previous owner any type of CA will not work, I need to go in with epoxy. The epoxy needs to be low viscosity since I will be poking small holes for the glue to deep in and harden. I want to do this repair right.

Despite the bad landing, I am very happy about the DLG thing. To think a spent on a 4m Pulsar (installation in progress), I could have had a very nice DLG.

I went to Long Beach in the evening to fly my electrics. The wind was constant. I would not have enjoyed as much with my DLG, this is where a motor helps to extend flight times. At least you get extended stick time.

I assembled my Supra for a trial run, it was 7:15pm and getting dark. I did a fully assembled motor on trial launch, but no flying. I couldn’t tell how the ship would respond after letting go. I might have someone launch it for me so I can be on the controls ASAP.
Posted by mechmove | Aug 23, 2021 @ 09:07 AM | 12,730 Views
For the next launch, I will not be using any wing camber, will set CG to 100mm, and elevator to -1 degree, UP. I will check “pulling” power regarding what attitude the plane will want to climb prior to release. I do not know if that is it good indicator, it could have been coincidence I ‘felt’ the plane wanted to climb more vertical rather than horizontal. I should have stopped the launch right at that time.

I’ll see what kind of trim will be required at altitude.

I want this to work, I need to move on to other things.
Posted by mechmove | Aug 22, 2021 @ 10:05 AM | 19,764 Views
Any day I can fly is a good day, but there are rare occasions where I am able to experience something in RC that will change my future as a pilot. I had such a day yesterday when I was able to fly my new DLG with assistance from some of the experienced folks in Long Beach.

I started the morning early to download and install Adrians’ 5.1 version of his DLG software, available right here. Installation worked like a charm, and most things were set almost immediately. The power of open source! I drove to Long Beach in light rain. Everyone was flying and picking up thermals in moisture!

One thing I learned, the launch button needs to be on a momentary switch. After an inverted launch, I practiced without it. My launches were more horizontal, but didn’t cause a problem in a empty field. I was able to engage 1 low level thermal, but didn’t stay with it since I am still learning the plane.

After coming home, I enabled the new Sl switch on my new x9d + 2019, for launch mode. I was able to figure out the location of the momentary button being far to the right means you have to hold the transmitter vertical during launch so your thumb does not accidentally engage the rudder. It also prevents the right arm from engaging the primary flight controls during launch. This is a very clever design!

Still, I am considering upgrading the existing leftmost switch to a robust momentary, the same one some guys at the field have installed on their transmitters. A few also installed a hand harness using a dremal tool so a neck strap is not needed.

I am very grateful to one of the DLG pilots on this forum who sold me his BCH DLG. Without this, my future in RC wouldn’t have taken this turn.
Posted by mechmove | Aug 19, 2021 @ 11:50 PM | 32,927 Views
After installing the latest firmware updates to my radio and receiver, these are my first impressions. Pretty cool to have "out of the box" telemetry in a tiny receiver which displays signal strength and a vocal "telemetry lost / recovered". What I would have given to know this when I lost my AVA back in 2013.

I downloaded an excellent DLG template by jfrickmann on Github: I removed the tail weight, and set CG to 76mm from leading edge with the new receiver mounted in the nose, and the battery under the wing.

I was able to dial in elevator and rudder. I still need to fine tune the ailerons, and assign flight modes to the desired buttons. I downloaded some voice files for each mode. FrSky seems to be the best of the Open Source concept, affordable price and good support from the user community.
Posted by mechmove | Aug 18, 2021 @ 08:52 AM | 20,348 Views
I’ve always been a simulator person. Even before I got my PPL, I was doing desktop flight simulators. This makes me a gamer. I believe simulators can make you a better pilot whether are you are a real world or RC pilot.

Consider what happened to me last Saturday at El Dorado State Park. When the airplane flipped on its back and started climbing upside down, it was instinctive for me to dial in the correct control inputs in order to climb to a safe altitude, without thinking too hard about it. I could’ve cut the power, or attempted recovery way too low and had a bad outcome. For any pilot who has practiced aerobatics, this is a no-brainer. But for someone like myself the only way I could become acquainted with inverted flight was with Real Flight and the USB control. Last month, I started doing aerobatics in the Mistral glider purely out of fun. I never actually thought I would fly any of my gliders in such a manner as my interest is in thermal duration flying, not aerobatics.

When I put the entire thing in context, I was actually practicing unusual attitudes in Real flight. If you have a PPL, you probably considered spin training even though it’s not part of the FAA exam. Even though you know the theory, you would be safer knowing how to recover an airplane in a spin in a controlled environment with an instructor. Before I got my PPL, I was flying in a Virtual air traffic control environment with full voice. My flight instructor did comment that my radio work was excellent. It’s not about me, but how I practiced. These techniques which are available to everyone. Many real world pilots today use Microsoft flight simulator to practice approaches into new airports.

Every RC pilot should spend time playing in the simulator as a matter of keeping skills up. Make sure to go out of your comfort zone. You never know what you’ll encounter at the field.
Posted by mechmove | Aug 16, 2021 @ 09:16 AM | 22,080 Views
Sunday, El Dorado State Park, arrived at 3:40pm. Weather was clear and hot and some wind. Flew my Alpha 2m, relaxing, fun, no surprises. I specd out once, needed reflex and steep wide turns to lose altitude. Comes down fast.

I worked on fine tuning crow settings, which is on my left camber slider switch. Previously had flaps only. Dialed in some spoilerons for steeper approaches. Probably need more for better short field performance. The steeper the approach the more difficult it is to flare for a soft landing. Although the fuse is lined with carbon for hard landings, a thick grass field helps.

I also configured a tiny amount of up elevator for launch on the left momentary switch, just like the hand-launch folks. Will experiment with adding launch camber for medium power climb-out next time.

This is what flying should be, learning with no hassles or headaches.

My frSky gear arrived today from FedEx. I expect to have my DLG up and running sometime this week.
Posted by mechmove | Aug 15, 2021 @ 12:59 AM | 16,366 Views
After coming home from dinner, I dispatched myself to the garage and started my formal inquiry regarding tonight’s Supra incident. The initial problem: the motor ON hand launch resulted in a backwards inverted climb-out. Maybe it will become “a thing”, its not a bug, it’s a feature!

Almost everything was where I had expected it, I was on the correct radio program, stab trim was zero and matched the wing incidence. One thing was off, my battery was positioned for cg at 108mm from LE which is considered way aft. That was not intended. But I was able to fly the ship with lots of forward elevator pressure after turning it right side up.

The question is how much down-trim would be required for a safe and predictable climb-out? I shouldn’t have to guess this number.

Previous launches had about - 7 degrees of trim, and it stayed there. Negative pitch on a full moving stab means UP trim,

With CG way aft, it appears zero stab trim results in too much UP. It was as if the elevator was in the full BACK position for a straight up, then a pitch backwards climb. Never saw an airplane do such a stunt. Did the rearward CG contribute? I would have expected a downward pitch when going from -6 to zero degrees on a full moving stabilizer.

When I looked at the stab at the field after landing, it looked like there was too much UP elevator. I never changed the stab trim, there was no time during the flight. Based on this visual, I would have known that down...Continue Reading
Posted by mechmove | Aug 14, 2021 @ 08:28 PM | 15,627 Views
I arrived around 3:30pm, warm temps, some clouds, 10% chance of rain. Very little wind. I confidently assembled my Supra with my well planned changes. I launched in the glider area. This time, the ship went straight up, then went in back of me, proceeded to climbout inverted. OK. I quickly adjusted to the situation and proceeded with an inverted climb. I might very well be the first to report the Supra has good positive control characteristics in an inverted state of climb (the ship was capsized). By this time I had rolled to the right, and I was over the electric area where someone was flying. I resumed my climb up until I was high enough. I cut the motor and turned the ship right side up and was able to land long after some circling but with considerable down elevator. I can’t make this stuff up. I wish my real life was this exciting.

The wings almost separated because I used only masking tape. I did bring stronger tape, but decided not to use it since I was absolutely certain I was going to have a very gentle, peaceful and uneventful flight.

So, what the h#€€ went wrong? It’s pretty clear the stabilizer trim was way off, after I was so sure I corrected it. Since the ship is fully intact, next post will be a full analysis.
Posted by mechmove | Aug 14, 2021 @ 01:19 AM | 19,596 Views
When we build our models, we try to ensure solder connections are solid and secure, shrink wrap is tight and there is no exposed metal. Once in a while, we find an interesting situation. Take the following short video that I made. It is of a 4 cell NiCad battery pack powering a Futaba FASST receiver. If you notice, there is an intermittent connection as I move the receiver with my hand:

Intermittent connection between battery and receiver! (0 min 19 sec)

For those of you short on time, here is the upshot; this battery connector could have caused the crash of my electric AVA back in 2013.

Here is the complete story.

A while back, I had just rearranged and re-soldered that battery pack for my Supra, where it was going to be deployed. Fortunately, it never made it, and I dumped the receiver pack to save weight. Then I noticed this problem. I could have been grateful it was never deployed into one of my gliders, easy enough to toss the connector and move on. But the question is how and when did this connector become damaged?

I have only 2 gliders that had external battery packs, my Supra and my AVA electric, which crashed. That connector could have been in my AVA electric before the crash. Or it could have been in my Supra, which never experienced a sudden power loss. Additionally, the intermittent connection problem might have been created as a result of post crash forces while in my AVA. Or maybe it failed recently, and I just became aware of it. I cannot know...Continue Reading
Posted by mechmove | Aug 13, 2021 @ 08:48 AM | 20,047 Views
Earlier this week, I placed my order for following items to get myself out of the stone age and into the modern era of Telemetry and Speech:

FrSky Taranis X9D Plus ACCESS 2.4G 24CH Radio Transmitter
FrSky ARCHER R6 2.4GHz ACCESS Receiver
Lumenier 2500mAh 2s Radio Transmitter Lipo Battery

This new setup will be driving my new DLG, it won't have telemetry to start, but those features will be on my other larger ships as I migrate to the more capable frsky gear. I like the idea of voice, instant feedback on whether or not you deployed the correct switch. Until I can outfit my DLG with the new FrSky gear, I'll be focusing on my flying my Alpha and Supra Electrics which are still on my old, but very reliable Futaba FASST.

FASST 2.4 was a huge upgrade, as my 72mhz would glitch even in remote fields with no one else around. Even though I was new to flying, my flying skills couldn't have been that bad. My version of 72 was not PCM, which I believe was available at the time and offered a better signal. I did lose my electric AVA back in 2013 while on FASST, but after reexamining some of the electronics that were likely in my AVA at the time of the crash, I believe now it was unrelated to radio signal. I believe it could have been a battery connector. Although my recent findings are not 100% conclusive, they explain how my AVA went completely "limp”, consistent with a complete loss of receiver battery on final, and not loss of control due to wind. I think the wind likely nudged the dedicated receiver battery that had a compromised plug. I will post pictures of the damaged ship and my recent findings in a future post. I will try to make a video, as I believe this is an important finding.
Posted by mechmove | Aug 10, 2021 @ 09:17 PM | 16,647 Views
Many years ago, a competitive RC glider pilot told me about some individuals or teams experimenting with making inflight CG changes with a weight that moved back and forth with a Servo. “CG on a stick”, I don’t know what ever became of such an idea, or if it is even legal for competition. But it is intriguing. I would guess more forward for speed, more aft for thermaling, kind of like reflex and camber. Maybe it’s a squared function, use both for a wider speed envelope, or use one or the other depending on desired outcome. Imagine using reflex and setting cg aft, or camber and cg forward, not sure if those combinations would serve any purpose. I could see the ship ballooning in both cases, buts it’s only a guess. Its a good thought experiment and a problem in mechanics, how much weight X do you need to move distance Y for desired cg change Z in mm? We can’t move the battery. I think the weight would need to be behind the battery, but the servo could be anywhere. Since it is holding a fixed weight in space, it is draining your battery. With competition gliders being as light as they are today, a large weight wouldn’t be necessary. It could be just an exercise in “what if’s”, but too difficult to implement with little to no competitive advantage.
Posted by mechmove | Aug 09, 2021 @ 01:14 AM | 18,570 Views
Today, I took out my new hand-launch to get a ‘feel’ for my new ship. I tried a Javelin style and a peg launch. The results were solidly unimpressive. Its a completely different world. I will wait for advice from the experts, otherwise I am taking risk with my new plane.

I quickly thought about how spoiled I am with a motor. The front mounted propeller generates enough lift under the main wing such that its already flying before you release the ship. Take away the motor, the pilot needs to propel the ship to altitude. The fact that anyone can do this with only a single ‘human’ propulsion event is noteworthy. Even the birds cannot do this, they flap themselves to altitude, and resume flapping their wings when the lift is gone. I suppose this is akin to having a motor on an electric glider.

In some sense, the DLG folks are exceeding the natural abilities of a bird. This is why I find the DLG world so intriguing. One launch, work the field, then spec out. This never fails to impress.
Posted by mechmove | Aug 08, 2021 @ 08:50 AM | 21,294 Views
Not by me though! I bought a HLG, ready to fly! Yesterday, I fitted my Futaba receiver up front into the canopy. One of the wings was noticeably heavier than the other, I’m not sure how it flew so well during demo, either experienced pilot or radio program. I added some weight at the end of the other wing for a perfect balance along the roll axis. Also a tail weight to balance the ship at 80mm from the LE. I had to readjust the aileron servo arms for my radio to just get the control surfaces flush with the rest of the wing. After considerable radio tuning, there is more down than up, this is opposite of what is the accepted norm in conventional gliders, but I cannot see why this would not work. Maybe HLGs are different. Will start fine tuning the radio for flight modes after the airworthiness certificate is issued.

I will be upgrading to a Taranis radio since the tech is better, the smaller receiver will allow me to put the battery back in the nose, and dump the lead.

Fun days ahead!
Posted by mechmove | Aug 07, 2021 @ 01:10 AM | 37,391 Views
Its August, and the dog days of summer are ahead of us. And the virus is even more contagious. The reason I re-started RC was my perception of being safe in an outdoor environment. I'm starting to think it might be prudent to wear a lightweight mask since I am interacting with people at the flying field. We aren't done with this thing yet.

Yesterday I received my TL90 Digital Pitch Gauge for Helicopters. I taped it onto my Great Planes Airplane incidence meter for a nice upgrade. Although the laser does work, it can be hard to use. I taped the gauge to indicate true zero degrees, as seen in the photo next to the construction level. This is important since it needs to lay flat on my stabilizer.

Now, the reason for this upgrade? I wanted to analyze my Supra's full moving stabilizer's default position with respect to the wing. I could go into a lot of detail here, its a comedy of errors, I didn't know what I was doing back in 2008, I took shortcuts, I stayed in a bad situation because I didn't know how bad it really was.

Here is the upshot, using the digital meter, my stabilizer had a -6.8 degrees of trim at launch. And it never changed. If I would have trimmed to dead center neutral 0, it would have been -6.1 degrees of trim. If I would have trimmed all the way up 100%, the ship would have been looking at -1.9 degrees of trim. If there is any redeeming factor in all of this, this means the ship was willing to fly, with considerable effort, despite the inadequate set up.

I...Continue Reading