VicT's blog View Details
Posted by VicT | Aug 12, 2019 @ 02:26 AM | 765 Views
My flying buddy has a stock CA and a Walrus that he uses for thermal soaring and for full throttle aerobatic practice and experimentation. He was using a Timber X for aerobatic practice but its in need of major foam repairs. The CA is holding up to this type of stress with minor foam cracks and tears glued back with regular CA. He uses the CA SAFE System for orientation recovery .

The Walrus is about half the price and does not come with a RX so he is using an orange 5 CH RX for motor, rudder, elevator, ailerons, and flaps. The Walrus does not look like it would be a good sailplane because the fuselage is much fatter than the CA. However the Walrus is stiffer and there is less wing flexing. Walrus has a thinner wing section and with upswept wing tips has better rudder only roll coupling. The glide is faster and has better lift even without changing wing camber. The power to weight and aerobatics are better than the stock CA. The flaps offer full trailing edge camber with ailerons and can slow Walrus down unlike the CA. The Walrus prop shows stress marks and if it fails/seperates could cause a serious body injury during a power on hand launch. The Walrus would be a nice inexpensive aerobatic trainer/motor glider with the Timber X receiver in her. I'll be on the lookout for the similar looking but discontinued ELuna from Tower Hobbies.
Posted by VicT | Aug 02, 2019 @ 06:40 AM | 1,272 Views
The Valiant 1.3 Landing Gear (E-flite - Valiant 1.3 Landing gear set - 4955) can be used on other models with a little modification. I have purchased (under $15) and installed about 8 so far in Apprentices, Timbers, and Turbo Timbers. The gear comes with screws and a tailwheel that fits the Valiant. The gear might be on backorder and I had to wait a few weeks for my latest shipment. If you are looking for one of the best SAFE intermediate sport designs purchase the whole model (with the AR636 RX) as its my favorite plane to instruct with. It is slightly smaller, faster, and more aerobatic than the Timber but can land slow with the nice flap design.

For the Turbo Timber remove the screws that secure the stock landing gear. I put all the wheels, legs, springs and parts in a large plastic baggy. This way you can trial fit the Valiant gear into the battery bay without interference. The U shape portion of the gear is designs so that the battery can fit between the legs. I put the U shape all the way aft in the battery bay and secure it with low temp hot glue. If you need to remove the gear then use 95 percent alcohol and a small brush to break the bond. For my original Timber (that does not have the 4 carbon fiber reinforcement tubes) I made up some balsa ply sides to reinforce the foam fuselage. These sides support hardwood so the included screws can be used to remove the landing gear for float gear installation or for belly landings.

The wheel...Continue Reading
Posted by VicT | Aug 01, 2019 @ 11:32 AM | 1,935 Views
I recently got my old Radian Pro (RP) back. It was going to be converted to a Taranis TX/RX system for RSSI, Battery Voltage, Vario, and Altitude Telemetry. Eventually it will but I wanted to fly her with SAFE Self Level and so this is how I did it. The RP was flying using the DX9 Sailplane program with an old AR600 long range receiver. Flight modes and programming worked fine and I wanted to keep it but add SAFE Self Level using a new RX.

The Turbo Timber (TT) SAFE receiver was a new open stock version that Horizon programmed for the Turbo Timber. So I used a new model in my DX9, bound it (with the bind plug removed) and named it RadPro TTSafe RX. I connected the RP elevator servo to verify the old elevator servo would move and direction was correct. It was not so I reversed the elevator and with Self Level On put nose down, tail up and verified full up elevator. I then made sure that Rx Port Assignments channel 7 was on Aux 3 and that Channel Input Config Aux 3 was assigned to my B switch. The RX can turn SAFE On and Off with any channel that your TX has from 5 to 9. I then scrolled to the Monitor page to make sure that when the left and right sticks were down and in I read -100,100,-100 and -100. This was confirmed and I toggled the B switch until I saw the elevator and rudder twitch. Then I put the nose down and tail up to make sure the B switch turned SAFE on and OFF. The B0 position turns SAFE On and B1,2 turns SAFE Off.
The old AR600...Continue Reading
Posted by VicT | Jul 28, 2019 @ 11:38 PM | 1,647 Views
I was timing for a pilot during a recent Altidude Limiting Endurance contest (ALES). Most pilots were using the Radian motorglider and having trouble landing within the landing circle. Most were landing outside and getting zero landing points. The Radian has no flaps or spoilers so approach planning and touchdown is non standard. A random circling approach or a low fast approach is about all you can do. When you want to come to a stop you nose her in to the grass and hope that the spinner, prop, and motor are not damaged. Of course if you use motor you save your Radian but get a zero for the flight.

The stock Radian comes with a white plastic skeg that is about 1/4 high and protects the white foam from getting scratched. If the plastic supported a music wire skeg I think it would improve the concept of protecting the prop and also improve spot landings in grass and other runway surfaces.

The following pic and diagram shows the concept of the music wire skeg mod. I will be testing a main wheel and rudder wheel for maneuvering on the grass and hard runway with my Night Radian. Other ideas are encouraged and welcomed.
Posted by VicT | Jul 27, 2019 @ 09:46 PM | 1,917 Views
The Radian has no drag devices but you can use the prop to add drag. Go into your DX6,7,8,9.....TX throttle curve menu and change the straight line points to a lower slope. Turn the curve to on and change point 2 to 5%, point 3 to 10% point 4 to 25%. You will not see a curve but adjust the points so that at half throttle the prop just starts to turn. In flight when you might not be able to see the prop turning move the throttle stick to the halfway point and you will be in the area where the prop just starts to turn. You will be providing windmilling thrust which is actually drag. Make sure to close the throttle just befor touchdown to avoid a prop strike.
Posted by VicT | Jul 27, 2019 @ 09:24 PM | 1,724 Views
The stock plastic clevis that comes with the Night Radian and many other Horizon models has a weak axle that will bend and break when you try and insert it into another control horn hole. If you make the hole bigger and insert the axle into the hole and secure it with the rubber tubing it will work but if the hole is oversize then you will get slop in the elevator, rudder, aileron control. If the axle breaks, separates, and falls away you will have no control. In the case of no elevator you most likely will crash. Dubro recognized this poor design and has a metric plastic clevis that will fit the 1.3-1.5 threaded rod and has a larger and stronger axle. You will have to drill out the control horn holes for the Dubro clevis to fit but it works great and is a great replacement. Here is the link to the part:
Posted by VicT | Jul 08, 2019 @ 11:48 PM | 3,469 Views
I have a blog for a top battery door for the original Timber but this is for the Turbo Timber. It might work for the original Timber but you are on your own.

Ive had no structural problems with this TT mod. Ive had about 100 flights and with no crashes it has held up. If you crash or damage the model in any way the whole aircraft must be inspected and fixed before the next flight. In my experience most flyers and especially beginners try and fly with a damaged model without fixing the crash damage. Then they blame their crashes on the models design. Enough Soap Box. Read on if you want,
The TT has 4 carbon fiber tubes that connect the motor mount to the main cabin area. The surrounding foam supports the tubes and acts as a wind fairing. By cutting away the top surface of the fairing the tubes are not compromised.
The top cowl and windshield are cut away with a new small size box cutter. Remove the ESC and any light wires to eliminate accidentally cutting those wires. See pics
Posted by VicT | Jun 22, 2019 @ 12:51 AM | 3,796 Views
Retracts have been well worn and work good on plane stand but on takeoff they dont retract all the way into the wheel wells. I am using 4S and amps are under ESC limit. I replaced old retracts with new ones (stock) to see if this solves the problem.
The old retract was taken apart for inspection and to see how they work. See pics

Today the maiden with new retracts went great. The wheels go all the way up to the worm gear stops and the tires are flush with the underside of the wing!
Posted by VicT | Jun 20, 2019 @ 10:24 PM | 3,125 Views
Takeoff was with Self Level Off so I could set trim. After trimming for hands off flight for 3 or 4 seconds Self Level was turned on. Roll and pitch limits were verified as well as hands off level flight with all flap settings. A full flap landing with partial power was completed. On the bench Self Level was turned off, the elevator marked on the fuse and TX trim returned to neutral. Then the elevator clevis was adjusted to bring the elevator back to match the mark on the fuselage.
I exported the settings to Dales SD card then imported the file to his DX9 TX. Wireless buddy box fam training will be next.
Posted by VicT | Jun 20, 2019 @ 03:10 PM | 2,744 Views
Having the V900 receiver installed in my AT6 Texan with flaps and retracts I figured it would work as well in the T-28. Today confirmed my hopes. I had to move the elevator servo arm 180 degrees and move the servo to the side to relieve push rod stress and I added a servo reverser to the aileron Y channel. However I did not have to reprogram the receiver using the Windows software and program cable. The receiver was purchased as an open stock and Horizon at my request put in the V900 settings before shipping it to me. The old receiver can be used for other purposes.

First step was to pry the stock 636 RX out of the foam fuselage and to remove the white rubber glue using forceps. Then servo plugs were removed and placed in the new V900 RX one at a time. Most of the plugs had ID tags on them. If yours does not have tags I recommend using painters tape (I like yellow) and then mark them with a black Sharpie marker. I added a short aileron extension to the bind port as its easier to insert and remove a bind plug that way. I used 3M Dual Lock to secure the RX to the white foam RX area. Inserting a small tool (piece of credit card) can easily pry the Dual Lock apart in case the RX has to be taken out for another plane.

I had previously bound the RX to a new ACRO model and got the B switch to turn Self Level on and off. I then rebound the receiver to the old T-28 Non Safe settings and the B switch worked to turn Self Level on and off. After binding the elevator was reversed as well as the aileron. Rudder worked. I could have reversed the RX 180 degrees and possibly have only one flight control to reverse but I proceeded with the old fashion way of rotating the elevator servo arm 180 degrees. At this time I also swapped out the white nylon clevis with the weak pin for Dubros new black nylon clevis with the larger pin. I had to drill out the elevator horn to match the .063 inch O.D.
To be continued
Posted by VicT | Jun 01, 2019 @ 11:01 PM | 1,016 Views
Spektrum technical recommends:

1. Start with a new model and not an existing model.
2. Bind it with the bind plug removed. Make sure receiver is blinking when you bind.
3. In System Setup Channel Assign assign a switch to turn SAFE on or off. Any switch can be used between channel 5-9. The gear channel is 5. If the gear is used for retracts then use channel 6 to activate switch B. I like to use Switch B because its the easiest to toggle on and off with the left forefinger pad. The middle position (1) can be set to On or Off.
4. Move both sticks to lower inside position. In the monitor screen make sure throttle, aileron, elevator, and rudder are showing plus or minus 100 percent.
5. Toggle switch B between stops (0 and 2) until you see a twitch in the elevator. Stop toggling when you see this and confirm the switch works by holding the model nose down and tail up. SAFE On should give you up elevator. Turning it off should give you neutral elevator. Put model into a bank. The upper wing aileron should raise trying to level the wing. If you dont get this re toggle the switch again.
6 Once the switch is working you can name the model, select wing type (flaps), throttle, cut, rate switches, mix switches, and audio.
7. On first flight turn SAFE Off and trim the model at what ever minimum power is to maintain altitude (roughly 50 percent throttle) then land. If FM (flight modes) are used then trim for each flight mode such flaps up,...Continue Reading
Posted by VicT | May 23, 2019 @ 05:56 PM | 2,569 Views
I purchased a spare cowl and made a ply firewall to fit a 55 mm O.D. Aluminum Turbo Spinner. A yoke and collet matches it and holds 10x6 folding blades. A bungee ensures positive blade retraction. Extension is symmetrical avoiding start up imbalance loads. Heat damage from the sun warped the black painted plastic and it was removed and replaced with clear .012 inch thick plastic from a pastry container. Canopy glue was used to glue the clear to the white plastic and for screening over the turbine duct openings.

Dive performance with power off is increased due to reduction in prop drag. With a 4S 1500 100C pack amp draw is only 33 amps with 470 Watts of power. On a 20 second full power climb at 80 degrees (SAFE selected On) she climbed to an estimated 1000 ft and after trimming for a 200 ft left hand circle stayed at altitude for 10 minutes power off!

An ISDT BC 8-S shows battery remaining in percentage and in voltage. It can be viewed while running up the motor while straddling the fuselage from behind the prop.
Posted by VicT | May 13, 2019 @ 05:03 PM | 1,101 Views
Here is a video of a Twin Mustang in the Test stand. Purpose: to check for unwanted yaw and differential throttle (desired yaw)
Posted by VicT | May 12, 2019 @ 11:52 PM | 1,203 Views
I researched the Avios SkyMule thread to look for diff throttle programs and found Oxotniks program that reduces the inside motor.

Here is a copy of his post:

I also added throttle curves for both motors. Max Thrust is still available but most of the throttle will be from 3 4 stick position to 0.

I also added throttle cut to both motors using a mix.
Posted by VicT | Apr 30, 2019 @ 04:57 PM | 1,851 Views
Fellow clubmember Cliff started flying an Apprentice and then a Commander. He asked me if I could reduce the pitch up of the Apprentice at full power to a lower climb angle like his Commander. I showed him Flight Modes that could be used with his DX6 but he was unsure of that route. So I suggested reducing the decalage angle by shimming the trailing edge of the wing. I had some hard 3/32 inch thick balsa so started with one, then two and finally 3 layers of wood. The end result was a 5 degree climbout angle at full power with SAFE on (Beginner Mode). With full up elevator she climbed at about 80 degrees. Happy with 9/32 of shim we filled in the gap with a single piece of 3/32 and white electrical tape.
Posted by VicT | Apr 16, 2019 @ 10:48 PM | 2,182 Views
Today was a perfect weather day that started out (April 16, 2019) with cool temps (60F) but warmed up to about 75 by noon. Winds diminished to about 5 mph and no clouds. Lift was light but just enough for the Heron. I used the Lithium Ion (LiIO) charge setting on my $110 Hitech Black 2 pack charger. This puts about 90 percent into the Lipo 2200 3S 45 C pack and does not over charge the pack. On the first flight I flew for about 25 minutes using about 1.5 minutes of full power climbs. I only go full throttle for about 15 seconds each so this was about 4 or 5 climbs. After landing I had 55% remaining on the pack. I adjusted one flap and launched again into light but steady lift every where. After climbing to about 1000 feet and turning off SAFE Self Level I did about 1 minute of aerobatics with aileron rolls and loops. Max dive speed with SAFE on is limited to about 60-70 mph because the gyros limit dive angle to about 40 degrees. No wing flutter or flex was observed from the foam wings with aluminum wing spars. Energy retention is not like heavier fiberglass designs but is fun anyway. The full flaps and crow with full down elevator stick provides a nice 40 degree slow dive to a round out and flare right in front of you. The single wheel protects the belly and allows for friction free rollouts that are about 30 feet long . There is not friction on the wheel but if it had then this could provide for less rollout distance.

I am still learning...Continue Reading
Posted by VicT | Apr 05, 2019 @ 06:45 AM | 1,993 Views
Originally Posted by Mark 2
Well Ive pulled the trigger, so mine is on the way.
Im thinking about using the 6ch Spektrum antennaless receiver, do you guys think that would work OK in this plane? Only thing Im worried about is the size of the battery possibly blanking the receiver at some angles.

It should work but I recommend an AR636 SAFE Select Receiver. It does not have signal strength telemetry like the antennaless receivers or the Taranis/Frysky systems. You already have a DX 6-9 transmitter right?

See my blog on why Im using the AR636 wing leveling feature to minimize prop and wing surface contact. Will post flight test results in about 2 weeks using the V900 636 receiver.
Posted by VicT | Apr 05, 2019 @ 06:31 AM | 2,067 Views
Originally Posted by Mark 2
Well Ive pulled the trigger, so mine is on the way.
Im thinking about using the 6ch Spektrum antennaless receiver, do you guys think that would work OK in this plane? Only thing Im worried about is the size of the battery possibly blanking the receiver at some angles.

If you dont want to have the benefits of a SAFE receiver then yes. I have the 4ch antennaless receiver in a DHLG 60 inch glider that has carbon fiber imbedded in the Kevlar fuselage. Its a 8.9 ounce David Forbes Vixen that I dont want to lose. The nice feature of the 4 and 6 ch design is that your DX transmitter shows signal strength in various aircraft positions where battery and metal, and carbon can interfere. To verify and validate adequate signal strength this I had another pilot point the CF fuselage and tail at me about 1000 ft away. I could barely see the rudder and elevator move but we had cell phone speaker comms open to coordinate the test. I found no low signal strength values at my DX9 telemetry screen and flaperons, and rudder and elevator worked perfectly. The nice feature of this new design is that you could use 3M Dual Lock (not flexible velcro) to mount the RX in the wing to test signal strength. When testing is completed you would have less connections at the wing and fuselage.

I like to have gyro technology level my wings on crosswind landings and takeoffs. This will...Continue Reading
Posted by VicT | Mar 29, 2019 @ 10:36 PM | 2,272 Views
This applies to Turbo Timber and any other design that uses foam or some other type of material for flight control hinges.

A hinge that gets loose on any flight control surface will cause erratic control in flight. If the hinge fails and the flight control departs the model then a crash is most likely especially if it is the elevator.

My Turbo Timber showed failure of the plastic elevator hinge. It was easy to see when I removed the stab/elevator for maintenance. The elevator was easy to move up and down as viewed on its edge. Many use the same center mounted nylon hinge with or without a metal hinge pin to fix a loose hinge but there is a better method that originated back in the 40s and 50s and is a variant of the thread and needle used way back then. Its called Tyvek paper hinges.

I use the Tyvek paper that is used on mailing envelopes. I lightly sand both sides with 220-320 grit sanding paper and cut to size. Using regular (not foam safe) CA I glue the hinges to the top and bottom of the elevator and stab. I use Monocote plastic backing to push the paper and glue on to the sanded foam and this prevents the CA from sticking to my fingers. You can paint the white paper or protect it with tape.