Cornell Rewinged

The other day was crazy windy. We flew only a couple flights, and they were a lot of work against a heavy cross wind with 10 mph winds and 20 mph gusts Stupid fun flying. So it was a great time to take my Eflite PT-10 Cornell up! Kenny Chandler, the only other flying fool, asked me why I hated the Cornell... then as I headed out to the flightline crabbed his camera and said he just had to film this!  (Here's your sign... but I was being bold!). Touchy cross wind takeoff in a plane that begs to roll the upwind wing, flying 45 degrees to the wind to run down the center line, kiting around turns near the tree line. There's always a nice burble on windy days along the tree line at the south end, and I flew into it. She rolled the wing nearest the tree line down hard, I compensated, she did it again, I over compensated... a nice pilot induced oscillation, tip stall, POWER, stall, crashes onto her wing. But it was a WILD ride!

Yesterday I redid the wing, and today the cote. Getting the cote right was tough as I learned how to use the heat gun (LOVE the heat gun for cote, but there is a very very thin line between shrink and melt...). I decided to redo the cote on the vertical stab... that was a pain in the ass and I redid it 3-4 times. The left side still isn't right, and I was too tired to take any pics... the wing came out pretty good though!

Pre-repair with the cote removed, underside right wing. The wing is broken clean through aft, a couple ribs and the leading edge spar, held together here by the top cote. I carefully peeled the S of U.S. off and would replace it later. 

Repaired the ribs and spars. The wheel box was shattered, though you can't tell from the pre pic. I had to remove the sheet balsa, reconstruct the box with the existing parts, build a new roof under it and then re-sheet the balsa. In rebuilding the cracked spars I used the technique below to add supporting wood behind existing structure.

I use popsicle stick wood, Dremel sand some arcs to reduce weight.

The wheel box is re-sheeted.

And the underside cote is done nice, clean and snug, using my newly developing heat gun skills. I did the underside easily, but the topside took a couple tries. I also put the S back on and made new periods.

But it too came out near perfect.

The dihedral is spot on, no new twists that I can see. The new wheel box is sturdy.

She looks great, though I wish the left side of the vert stab cote looked better... next time.

No pics, but I decided to change the motor. I had a HURC 2836-09 driving a 10x8 Master Airscrew powered by 3S 3300. I think this was a marginal power setup. I decided to change to a HURC Power Up 450 motor Kenny Chandler had given me. for a few more kv and 50 more watts of power without any more weight up front (remember she has the metal motor mount, so front end weight is an issue). I think she will fly a tad better, and can even handle a 4S if I want to. Hoping to fly her tomorrow!

UPDATE (1/1/12): Went back this morning and redid the left side of the vert stab, and it came out wonderfully. I also took a moment to strengthen the structure of the frame, which you can see through the cote in the pic of the right side.

Bad ESC update

Turns out Ray was right. He responded earlier to my my badESC post noting maybe the ESC throttle limits hadn't been set. He was right! I installed the replacement ESC and it did the same thing, alarming and not functioning. So I set the ESC throttle limits. After binding the receiver turn everything off and remove the bind plug.Turn on the transmitter, then move the throttle to high/full. Now power up the reciever. After the first start tones finish, within two seconds of turning on the receiver, pull the throttle back all the way. Let the ESC startup finish. It should no longer alarm, and the ESC should function properly. It works fine now! Thanks, Ray!

I NEED MORE POWER, SCOTTY!

The good news is that my Hangar 9 Sopwtihfits in my new car. I traded in my Lexus IS 350 for a more economical, and while smaller, roomier Lexus CT200h. Now I don't need to borrow  my wife's crossover anytime I want to fly more than one plane, and driving to the field doesn't cost me $10 in gas. I actually like this car better than my IS, and I loved my IS.

Its a tight fit, but it works! I was able to get my Eflite Pulse XT25e, my Electrifly Cosmic Wind, my two PDYSysytems carriers, my battery charger box, and my radio box all in there. Very nice!

The bad news is she still flies like a pig... She took off from the middle of the field and this time rolled left despite full right aileron and then right rudder, and back into the ground. She bent her motor mount, broke her prop, cracked the cowl, knocked a piece of the mock motor out, and broke her wing. When the wing twisted, the wires snapped, again. Looks like I lost a turnbuckle to boot. Vinsen was there and he echoed my concerns since the first flight, that the motor is not powerful enough. She has a 14x8 prop, lifts off, but doesn't seem capable of controlled flight, just waffles. I ordered a true 60 size motor from Heads Up RC. The plane is stock recommended for an Elite 46, which my installed HURC 4260-06 motor is a replacement for. Many builders have done fine with the Elite 46, but most are recommending steppjng up. Since her power has been bothering me, I opted to buy aHURC 5065-04 motor, which is equivalent to a true 60 size motor. I also purchased a Hobbywing C-Platinum 100A ESC, to upgrade from the installed 70A ESC. I wonder if I should step up from the 14x8 prop? This motor has a lower KV, but I am also going to ramp up to 6S from the 4S I had tried. My fear is she will just crash harder...

Thunder Tiger eHawk 1500

Yesterday was a marginal day flying at BMF. Very windy, which limited our flying. I did take the Hobby King ASK2100 up. We know how she flew last time we tried that.

I flew her a couple of times... but she hated the winds. Her wings flexed  and bent in flight, her tail twisted, and she was a bucking bronco between being carried by gusts to following her own lead when her control surfaces twisted in flight. It wasn't any fun, and every flight ended in a tip stall. I gave the controls to Paul Minnick. Immediately after launching her she kited up and backwards, then flipped nose down as she shot over the pits. He cut power to avoid the pits, clearly having no control over her, and she simply drove herself into the ground. He felt awful, I felt it was inevitable. She was a terrible aircraft. So I removed the receiver and gave all her parts to Greg Reed, who loves a challenge.

I still love my Diamond 2500, but I am done with foamy gliders. I need a new glider, less than 2 meters, power, and not foam, for a low price. I like T-tails, but that means fiberglass (or heavy foam like the Diamond), but I also like V-tails. I found this Thunder Tiger eHawk 1500 at Tower Hobbies for a very reasonable price. I couldn't find any legitimate gripes about her. I watched several vids and liked the way she flies. I will build her stock but want to work on giving her separate aileron servos (don't know why they didn't do that) when I can figure out how to make the cuts in a new servo tray. She needs spoilerons or will be challenging to land at slow speeds. She should get here by the end of the month. Looking forward to her and learning how to program V-tails!

Waffly Warthog

Took the A-10 Warthog up yesterday. She really didn't have enough thrust to takeoff from grass without a good head wind. She rolled fine on her big wheels, but she just didn't have the thrust. I did manage to takeoff once into a gust, but otherwise I hand launched her.

The pic in the manual that sets the CG at 80mm from the tip of the pylon is incorrect, as one might imagine. I set it about a third back from the leading edge, which put it over the spar, and it was spot on. I had set my low rates for elevator at 50% with 25% expo. She porpoised a lot, so I ended up setting it at 35% and it settled down. Elevator authority is no problem! She is marginally powered with the two 64mm fans on a 3S. She has 40amp ESCs, so she could handle a 4S, but I would have to chisel EPO, and I don't know if the extra weight would bog her down more than the 4S would improve her power. She hand launched easily, but her size and power require she be launched by a flying buddy. Once she waffles up to speed and is truly airborne she flies fine. She is no speed demon, but she is quick. She trimmed out easy, and once I got her elevator expo set she flew quite stably. On landing with power off she loves to float, and her gentle stall behaviors let her come down nicely.

I did have problems with the retracts. They bind, and it took some surgeries on the case to resolve that. The cheap stock servos on the mains burned out, one yesterday, and another today. I replaced them with Tower Pro SG-90mgs. Yesterday's went in no problem, but today's was "reversed" so the left main was out of sync with the nose and right main. The servo was moving correctly, but the installation would not let me put it in "backwards" to get it in sync. I don't know why this servo was different than the stock one, but it is, even though its installed the same. I ended up getting a servo reverser, and its all set now. I didn't get to fly her today due to this retract issue...

Tomorrow I hope to take her out and see if I can takeoff from the ground. Hopefully the grass will be cut before then so I can get her rolling!

BlitzRCWorks A-10 Warthog

Its not like I needed a new plane, but I go this one during the Black Sunday Sale at Bananahobby for less than half the price, in fact, almost a third. Its the BlitzRCWorks A-10 Warthog. I had wanted the camo one, but it was NIS, so I got the Black Lightening one. She is very nice! In set up one of the landing gear retract servos burned out, but the rest of her is working just fine! I didn't blog the build, it was very simple: bolt on the wings, stab, etc. The multiple wires took a bit of time, but that was easy too. Some areas of paint came up with low tack tape so had to be repainted. I set her up with flaperons, and slowed the retracts down to 3 seconds.  Her wheels are large enough she should have no trouble with the grass runway at BMF! Looking forward to flying her soon!

Salvage...

Went through the remains of the Diamond 2500 Power Glider... the rest goes in the trash.

Silver on Red

Kenny Chandler suggested a silver prop spinner would look smokin' on the nose of my very red Cosmic Wind, so I ordered one from Maxx Products International (MPI).  What do you think?

Before: Red Spinner

After: Silver Spinner

Physics is consistent, I'll give it that...

Well, yesterday I flew the ASK 2100 power glider, and landed her with the spoilerons with good speed, and she landed sweet with remarkable sink. I am also aware that she will tip stall like crazy. And I know that if you want to tip stall more spectacularly use spoilerons at stall speed. So what did I think would happen if I made my approach at just above stall speed and tripped the spoilerons, especially after I saw her do it twice at altitude while slow flying today. She tip stalled and dropped like a rock right on her nose...

Despite a fairly high speed spinning crash she came away pretty well. The nose is cracked on both sides as can be seen here, with a little foam squish. The motor and motor mount are fine. The long canopy snapped on the foam part. Epoxied everything back together easily. Good as new!

I tried a carbon fiber spar in place of the aluminum spar, which of course had no dihedral. The aircraft flew much better for being lighter and didn't seem affected by the loss of the dihedral. But on flaring for a landing the spar snapped and she dropped to the ground in a semi controlled landing. I put the aluminum spar back on and curiously, she still flew well! Today she flew more stably than she did yesterday. Conditions were much, much calmer. Flew her several times and she was a pleasure! And then I tried to defy physics...

Tomorrow is supposed to be an even better day! I am nervous because I plan to maiden the Hangar 9 Sopwith!

Hobby King ASK 2100 Glider

Clearly its not my Art Tech Diamond 2500... I killed that, the first plane I have ever demolished. Today I maidened my Hobby King ASK 2100. Its smaller, 2M power glider. The power is adequate using a 25 amp ESC and a 3S 2200 battery. She arrived in an unmarked box from Hobby King's USA warehouse. Unboxing I found there are no instructions, and like everyone else's, the rudder was broken off the airframe. I used CA hinges with foam safe CA, no problem. Despite the lack of instructions she went together quite easily. I like the wing setup, very easy to install and easy to dismantle for portage. In flight I found the aft part canted out from the airframe. I used packing tape to keep it snug. There were two ginormous lead weights, not sure what they are for, but they weren't needed. She has an aluminum spar that is rather heavy. replacing it is a goal, but it has a dihedral that makes using CF tube difficult. The airframe is slightly torqued so that the vertical stabilizer is a smidge off to the left of center. The elevator piece installs snugly with one screw and two posts. The connection to the elevator control wire is very thin, and it is lead into the elevator control horn and stays quite secure.

The conditions were cold, gusty with light winds. She powered up and flew easily out of my hand stable into a brisk gust. She climbed easily. Her frame is not very strong so she twisted out of control from time to time. I can see her wings twist on the fuse as she spins into un-commanded turns in a good wind. the wing tips flex a lot, a problem because that's where the ailerons are. In glide she is heavy, despite good CG she needs to nose down or she stalls. She also tip stalls very suddenly and hard, and takes a lot of altitude to recover, as some others have reported. She doesn't like to fly slow and she won't stay up long. I think its all because she is too heavy, and that damn aluminum spar is a big part. I think too she needs more chord. Despite all of this she was a pleasure to fly, I just spent a lot more time climbing to altitude than I did with the 2500.

I set her up with spoilerons, instead of my usual flaperons. This was really a good technique. She made her approaches floating like most gilders, even with a brisk head wind. I pulled out the spoilerons and her descent rate increased in a sweet and controlled manner. She landed flawlessly. I did stall her a couple times at altitude, not enough to recover completely, so she landed hard. No damage, pretty tough plane.

The 2500 is a big, big plane, but the price came down to about $159 at Nitroplanes... I would recommend it over this plane. I kept wishing the ASK 2100 was my Art Tech 2500.

Flying Wind

As in, my Great Planes Cosmic Wind being maidened on a windy day at BMF. I took her out to the field, and finally put in a battery and checked CG. It seemed really forward so I put an ounce aft to balance it. First flight was pretty tame for a maiden, some quick trimming. She flew fantastic! She needed a little left trim, a bit of P-factor compensation. It turned out she didn't need so much weight and on the second flight I flew her with only 1/2 oz a bit more forward. This time she was magic! Fast, extremely agile (ended up tuning the rates down to 40, 60 and 100% with 25 expo all across, flew her entirely on low rates and she still danced). She floats on landing, and has tame stall characteristics. With the 350 watt motor with the 8x8 prop, she screams, has really good vertical, and even with low rates she is very acrobatic. On landing she will float, and settles cleanly. I flew her in 10-15 mph winds with some brisk intermittent cross winds, and she handled them fine. The white decals look great and contrast well with the all red bottom. Visibility would increase if I put more on, especially the other wing, but I love the slick clean red fuse. I will be shiny-ing her up with some car wax, and she will be sweeter! What a great pleasure to fly, she is now one of my favs and will likely be with me on every trip out! Pics with my Eflite Pulse XT 25e. Awesome day of windy flying!

Kenny's "New" Stryker

Kenny had a few Stryker frames, and this last one was painted by our club prez, Dickie Ober. Kenny maidened it today, and it flew great!

A boy and his plane...

Kenny landing his Seagull Edge 540 this afternoon. It was a beautiful but really windy day. We had BMF all to ourselves.

Cosmic Wind

1947, the Goodyear races, a new airplane, the Cosmic Wind.  The Great Planes Cosmic Wind is a remarkable reproduction, and boy, is she sweet. I put mine together last week! I changed the graphics a bit. I will be adding a "435" to the other wing later, and keep the bottom all red. She has a Gens ACE Mars Brushless   98P-Mars-BL3738-1300KVmotor and a Gens Ace Mars-BL45A ESC (a combo from Hobbypartz) for her powerplant, for 350 watts (the stock recommended motor is 330 watts). She has a APC 8x8 prop, as recommended for the stock motor, and will be using 3S 2200 -2650 mAh batteries. She should SCREAM! Using Hitec HSG 82mg micro servos (single aileron, rudder and elevator).

The 435 will appear along the wings outer edge.

Looking forward to a maiden flight!

It was one of those days...

It was one of those days, beautiful conditions, great flying, awesome company at BMF. And it sucked...

This is whats left of my Diamond 2500 Power Glider. This plane has a wing that is a pain in the ass to put together. The servo wire connections snag or come undone, the two halves sandwich together, but never quite meet well. I spent about 20 minutes getting her together, powered her up and checked the servos, walked to the flightline and checked again, and the left aileron wasn't working. Set it down, took it apart and spent another 10 minutes putting it back together. Checked control surfaces, powered her up and launched. She rolled a bit right, climbed level, I input a left roll and she rolled right. I realized the ailerons were reversed and input a right roll to roll left, and she rolled even harder to the right, and slammed HARD into the ground. She shred herself completely. The motor sheared off and landed 10 yards away. Post crash I confirmed the ailerons were reversed. I looked but I did not see...

The nose is gone...

The force of the crash sheared off the ailerons, and warped the flaps. The tail snapped clean off. I have never demolished a plane so thoroughly (heli's yes, example below). She is unrepairable...

My beloved C-47 also crashed on her fourth flight of the day. She was in level flight about 50 feet up, when she did an uncommanded right roll and spun into the ground. She was near the Bermuda triangle of our field where many a plane has mysteriously gone haywire... My DX8 had 4.6V (NiCAD) which should have been fine, but we wonder if there is something over there that interferes with our signals. She was the second plane of the day to do this, both of us accomplished pilots. She should be in bits, but she only smashed her nose, cracked the left wing near tthe root, broke both cowls and damaged both motor shafts. Fixable, but damn...

This is what happens when you try to nose in hover because tail in got too easy... and you lose control. It reminded me why I love-hate helis. She flew awesome, got her perfectly tracking, flew several packs in hover and moved her around with great control. On her fifth pack I decided to turn her nose in, and she started to get away from me... BAM... have to start all over again. At least the servos survived...  Need to replace the tail boom...

and replace the main shaft, feathering shaft, and rebuild and reset up the CCPM, set up a set of new main blades. One mistake, hours of work... Its like golf: one awesome drive makes you forget all the pain and keeps you in the game. Nothing like flying a perfectly tuned heli to make you forget the Groundhog Day feeling of rebuilding her yet again. 

The day didn't completely suck... I flew the Sabre jet, the Ultimate and the Pulse a half dozen times each and had a rockin' time! No more flying until after Turkey Day!

Erazor hovers

In the past couple of days I went through several packs on the Erazor 450. I can't hover her high enough in the garage to get the tracking set, so that will have to wait until I get out to the field. She hovers wonderfully. Not sure there's a big diff with the Align GP 780, but then I haven't flown her per se. I did manage to burn out the Hitec HSG 5084 mg tail servo today. I know the gyro is set for the right digital frame, so that wasn't it. Swapped it out from the one on Frankenheli, since I plan on concentraing on one heli at a time. Looking forward to flying her!

I'll be working on the HDX500 next. I have the replacement servos, and I think I can figure out a replacement for the missing anti-rotation pin. I have never powered her up, but she came with a 4S battery, and I wonder if she would do better with 6S? I can series together a couple 3S batteries... lookig forward to flying her too!

Hovering the Erazor in the garage reminded me how much I enjoy getting the engineering spot on, and seeing the control I have improve with each hover. Exciting stuff!

Erazor Reborn

I finished rebuilding and setting up the CCPM on my Erazor 450 this evening. I had to replace the canopy with a Tacon, but I think it looks much sleeker! New is the Align GP780 gyro, top of the line. A little fine tuning and she will be ready to fly! Need to spend a lot more time on the sim first since I have gotten very rusty!

UPDATE (11/16/11): Practiced hovers in the garage today, flew great! I need to work ln tracking a bit, but otherwise the CCPM setup and gyro functioned perfectly.

Keeping the baby, tossing the bath water.

Following my 60mph landing the other day, one of the JR MN48 aileron servo's (possible two, not sure yet) on my Eflite Pulse XT 25e went bad, partially stripped gear. Its a $25 servo, not too expensive, but seeing that replacement gears were available at Horizon Hobby for a bit less than $5, I decided had nothing to lose by trying a gear replacement, though I did buy a backup servo. It went pretty well!

The bad servo removed from the aircraft.

4 screws, one in each corner, easily removed.

The bottom comes loose... close it.. we want the top.

The top comes off easily.

Take a pic of the gear set. You will need it later.

Especially this view.

The gear set. Can you spot the bad gear? Hint: its the one to the right of the bearing.

I had to remove the gear with the bearing, which was well attached and came off suddenly, taking the second gear and third gears with it as they are interlaced. I replaced the bad gear, and reinstalled the other gears. The gear on the bench is the stripped one. A touch of white lithium grease. Compared with the side view pic taken earlier to make sure I had everyone in the right place. Put the top back on, and replaced the screws. Put the servo on my tester and she ran clear and smoothly, centered perfectly! Reinstalled the servo in the aircraft, and will test it in situ later. Very easy, and from now on a option I will take whenever replacement gears are available. Much better than throwing out an otherwise perfectly good servo. New skills rock!