PT-17 Stearman

PT-17 Stearman side
Stearman top
Stearman partsUsing PETG to print the PT-17 Stearman

My third printed RC plane is this Stearman. I tested single layer printing on my printer in PETG for this aircraft. Information about my 3D printing equipment you find in the post; printing the Kodo.  You can buy the STLs and Simplify 3D factory files from 3DLabPrint. I used Makerfill PETG for wings and fuselage, Polylite ASA for the black landing gear components, and some other smaller parts. PETG print filament is similar to PET (Polyethylene Terephthalate) but with enhanced properties due to the addition of glycol (PET+G = PETG or polyethylene terephthalate glycol-modified). Due to the excellent strength and impact resistance, PETG is appropriate for stress withstanding applications. Being amorphous in nature, PETG has good flexibility, machinability, and thermoforming characteristics, which allows the material to be hotline bent and welded. Here are some of its 3D print advantages; excellent layer adhesion, warp resistance, reduced shrinkage, high water-resistant, high temperature resistant. The temperature tolerance for PETG is around 75ºC. With PLA, on the other hand, you generally have to keep 3D printed parts below 55ºC to keep them solid. The cons of PETG for RC planes are higher flexibility can lead to twisting of the wings or fuselage during flight and the rather high density leading to a higher wing loading. To get good adhesion between the layers for single layer printing I had to give more filament material by setting the extrusion multiplayer 1.03 for the 0.25 mm layer height. Printing PETG material has some cons; PETG has a high density of 1.27 g/cc, so the plane will be havier than printed in ASA, HIPS, and lightweight PLA. There is also a tendency to have a lot of stringing and it's difficult to make bridges. To solve these problems and keeping printing time reasonable I had to print each part in more than one process. So I could change the print settings for some heights areas. For example for bridging, I had to slow down and reduce the extruder temperature on specific height areas.  Also, to reduce the stringing I try tried to use a filament retraction distance as low as possible on my printer, and use some coasting- and wipe distances.  To make some parts stiffer I had to print some heights areas of a part in a double-layer wall. My printer setting for PETG: Printing volume 200x200x180 mm, Extruder 0.4 mm, Layer Height 0.25 mm, Extruder Temp 245-235 ºC, Filament Speed max 40 - 15 mm/s, Bed 80 ºC, Cooling 60%-100%.

Electronics for this PT-17 Stearman

I used an Extron motor 2826/10 KV860 Outrunner with an Extron iQ-40 ESC, 4 Savox SH-0255 MG (Metal gear) servos, a Spektrum AR6610T 6 channel receiver,  and a Gens ACE 3000 mAh.

Modifications

MOD1: Modified print processes to be able to make PETG bridges, avoid stringing, and to reinforce some part by printing some 2 layer bands.
MOD2: Modified motor section with extra an extra 20 mm motor shim, drilled holes in the 7 cylinders, and added approximately 70-gram lead to adjust the Centre of gravity.
MOD3: Modified the landing gear with metal springs and inox wheel shafts and copper tubes, and printed a higher infill in the front part of the PETG landing gear legs to get these stronger.
MOD4: Added A3Pro Gyro from Hobbyeagle to improve stability and the use of failsafe modes.
MOD5: To improve the looks I printed the plane in blue and red transparent PETG, the windscreens completely Makerfill transparent PETG, and the pilot chairs in Polymaker Polywood.
MOD6: Printed the tires in Makerfill Flex with no infill.
MOD7: The stripes on the ailerons, elevator, and rudder as are small pieces of red Oracover Transparent Fluorescent film ironed on the PETG.

Summery

Till now I did not maiden this RC Airplane. Al static tests were OK, the plane was certified for flying at or our RC terrain in Lier, Belgium, and I did a photoshoot. When the weather improves I will fly this plane.

Aircraft Characteristics after Modifications

Wing Span: Bi 1.2 m
Length: 0.9 m
Flight Weight: 2.7 kg
Wing Aera: 45 dm2
Wing Loading: 60 gr/dm2
Wing Cube Loading: WCL 8.9
Power: 4S 3000 mAh
Motor: Extron 2826/10 KV 860 Outrunner
Propeller: XOAR 1x 12x6 2-blade
Stall Speed: 34 km/u
Sound Pressure: 50 dB(A)/7m

Video

Photos

B-24 Liberator

B-24 Liberator front - detailB-24 Liberator side - detail

The Second World War Bomber Liberator is one of the most recognizable WWII aircraft of all time. Serving in every theater of that global conflict, the B-24 fought to bring its brave crews home through unimaginable danger. With humility and reverence, Flightline is proud to introduce the world’s first foam electric B-24 Liberator, in remembrance of the crews who gave the ultimate sacrifice and those who carry on its memory. The FlightLine B-24 Liberator is approximately 1/16.7 scale, with a 2000mm wingspan and 1230mm length, and is constructed from EPO foam and reinforced with integrated aluminum, carbon fiber, plywood, and plastic structures. The FlightLine B-24 uses four 3530-860kv brushless outrunner motors, 30A ESCs, 9.5 x 7 counter-rotating propellers, and a separate 5A UBEC. A pair of 4s 14.8v 3400 mAh lipo batteries powers the aircraft in of 1000km/h, for 5-10 minutes based on a pilot’s throttle management. Mid-throttle cruising for 7+ minutes of scale-style flying. The outboard motor pair and inboard motor pair are powered by separate flight batteries, allowing for powered landings in the event of one battery losing a cell. A 70mm tall nose wheel and 85mm tall main wheels provide stable operation on grass runways and split flaps aid in low-speed flight and landings.

Modifications
Used different types of Painting, Airbrush, and Weathering Techniques and used Oracover ironing film on top of the foam to change the look of this model. Added 3D printed interiors for the Turrets, Cockpit and Pilots, and additional Gunners. A Bomb space was created and two Bomb Doors were designed and 3D printed. The Top Turret can rotate remotely 360 degrees, and the Front and Back Turret are moving together with the Rudder control. The Bomb Space can contain 4 3D printed WWII Bombs or a Parachute with Soldier or Relief Supplies. Modified landing Gear with other tires. Added Spektrum Airspeed, Temperature ESCs, Flight Voltage, and Power Telemetry. Installed Spektrum 9 Ch with AS3X Gyro technology RX. Used a separate UBEC from Castle Creations and an Optipower Ultraguard battery with fail-safe switch PCB. Safety System with Fuse so the Battery Pair starts working separately when a problem occurs (Short Circuit or a Defective battery Cell). In normal operation, both Battery Packs are keeping the same Voltage. Installed a Sound Module Aspire from MrRCsound with two Dayton Audio DAEX25FHE-4 High-Efficiency Exciters and the B-24 Multi-Engine Sound to maximize the allowable sound pressure to 84 dBA at 7m distance. Added navigation lights and landing lights.

Aircraft Characteristics after Modifications

Scale: 1/16.7
Wing Span: 2 m
Length: 1.3 m
Flight Weight: 5 kg
Wing Aera: 40 dm2
Wing Loading: 125 gr/dm2
Wing Cube Loading: WCL 19.7
Power: 4S 6600 mAh
Motor: 4x 3530 KV850 Outrunner
Propeller: 4x 9.5x7 3-blade counter-rotating
Stall Speed: 48 km/u
Sound Pressure: <85 dB(A)/7m

Links

Spektrum – Meaningful Telemetry for Airplanes

Videos

Photos

T-28 Trojan

T-28 Trojan side - detail

T-28 Trojan bottom - detail

T-28 Trojan front - detail

I bought this plane secondhand and modified it but after one flying season, this plane was taken out of service to make room for 3D printed airplanes. The Trojan was a good flyer but had a lot of problems with a weak nose wheel retract. I recovered most electronics as spare parts for my other FMS planes.

The North American Aviation T-28 Trojan is a piston-engined military trainer aircraft used by the United States Air Force and the United States Navy beginning in the 1950s. Besides its use as a trainer, the T-28 was successfully employed as a counter-insurgency aircraft, primarily during the Vietnam War. It has continued in civilian use as an aerobatics and Warbird performer. The FMS 1400mm T-28 Yellow Navy Trojan V4 is a warbird with gentle flight characteristics and can be used as an RC-trainer plane. Equipped with shock-absorbing oleo struts, servo less retractable landing gear, working full-size flaps, bright LED navigation lights, scale details like chrome spinner and landing gear doors, secure ball links on pushrods, the multi-wire connector allows quick disconnect of wires for easy wing removal.

Modifications

Modified landing gear, low bounce bigger tires, soft springs, use 4mm Align feathering shaft for the vertical axle in nose wheel, added Rare-earth magnets to reinforce the closure of the cockpit. Used different types of weathering techniques to improve the look of this model, used black trim line tape. Used airbrush techniques.  Oracover ironing film on top of the foam to change the look of the model. .Added my own Decals ink-jet printed on Testors White Decal Paper. Finished with a gloss IR and water-resistant varnish. Added a Spektrum Airspeed pitot-tube, voltage, and Flight power telemetry. Put in a Spektrum 7 channel RX with AS3X technology. Used a separate UBEC from Castle Creations and an Optipower Ultraguard battery with fail-safe switch PCB.

Aircraft Characteristics after Modifications

Scale: 1/8.6
Wing Span: 1.4 m
Length: 1.2 m
Flight Weight: 3.1 kg
Wing Aera: 31 dm2
Wing Loading: 100 gr/dm2
Wing Cube Loading:  WCL 17.9
Power: 4S 3300 mAh
Motor: 1x 4258 KV650 Outrunner
Propeller 1x 13x9 3-blade
Stall Speed: 45 km/u
Sound Pressure: < 85 dB(A)/7m

Videos

Recently I have added a MRRCSound Aspire sound module with T-28 sound. See recent photos and video hereinafter.

Photos

P-38L Lightning

P-38L Lightning front - detailP-38L Lightning back - detail

The legendary P-38 “Lightning” revolutionized aviation history in World War II. Designed by a skilled team of engineers led by Clarence Johnson and Hal Hibbard, the P-38 was the only American fighter that was continually produced from before Pearl Harbor in 1941 to after the Japanese surrender in 1945. Over 9,900 P-38s were built, 3,810 of which were the superior P-38L variant. Revered by its foes as the “fork-tailed devil”, the P-38 excelled as a fighter, interceptor, reconnaissance platform, long-range escort, and as a ground attack aircraft. The aircraft also famously shot down Admiral Isoroku Yamamoto’s aircraft during “Operation Vengeance” on April 18, 1943.
The Flightline RC P-38L wingspan 1600mm is equipped with two 3748 brushless outrunner motors and two 12x7 3-blade counter-rotating propellers for the perfect scale appearance. With the recommended 4S 14.8v 5000mAh (one battery per side or a single battery with your series adapter), the P-38 boasts sufficient power for large consecutive loops and a level top speed of 125 km/u. A durable electronic retractable landing gear, five sequenced servo-driven landing gear doors, day-bright LEDs, machine gun details, plastic nose cone and cowls, four flaps, accurate canopy, and nacelle shape, and many other scale details. Each rudder is directly controlled by its own servo. The cockpit layout accommodates a wide range of 4S 14.8v Li-Po batteries with ample space for electronics. To ensure a high degree of structural rigidity, the entire model was designed around a special framework of carbon rods and reinforcement points. This framework strengthens the aircraft during high-speed maneuvers, while still providing a gentle and forgiving flying behavior.

Modifications

Used different types of weathering techniques to improve the look of this model. The first time that I used airbrush techniques. Oracover ironing film on top of the foam to change the look of this model and added D-day stripes. Added my own Decals ink-jet printed on Testors White Decal Paper. Added Spektrum Airspeed, voltage, and Flight power telemetry. Put in Spektrum with AS3X technology 9 channel RX. Used a separate UBEC from Castle Creations and an Optipower Ultraguard battery with fail-safe switch PCB. Recently added a MrRCSound Aspire 4.1 Sound Module with Exciters in the two Motor Compartments.

Aircraft Characteristics after Modifications

Scale: 1/10
Wing Span: 1.6 m
Length: 1.2 m
Flight Weight: 3.5 kg
Wing Aera: 27 dm2
Wing Loading: 130 gr/dm2
Wing Cube Loading: WCL 24.8
Power: 4S 5000 mAh
Motor: 2x 3748 KV650 Outrunner
Propeller: 2x 12x7 3-blade counter-rotating
Stall Speed: 50 km/u
Sound Pressure: < 85 dB(A)/7m

Videos


Photos

 

Spitfire Mk IX

Spitfire Mk IX front - detailSpitfire Mk IX side -detailSpitfire Mk IX back - detail

The Supermarine Spitfire is one of the most popular warbirds in history. This British single-seat fighter was used famously by the Royal Air Force and the Allies, earning distinction during the Battle of Britain and throughout World War II. Over 20,300 aircraft were produced with more than 24 variants. The Spitfire’s versatility and maneuverability in the hands of skilled pilots made it a lethal weapon against Axis forces. The timeless Spitfire continues to fly in modern times as a tribute to aviation history and military veterans.
FlightLine RC’s 1600mm wingspan Spitfire Mk.IXc is approximately 1/7 scale and an entirely larger beast with all the bells and whistles we’ve come to expect from aircraft in the 1600mm Class. This Spitfire is molded from EPO foam, featuring a scale shape and smooth surface. The main wing is assembled from hollow foam parts and an interlocking plywood and carbon fiber frame, providing lower weight and higher strength than a solid foam wing. The main wing and horizontal tail are attached with screws for very convenient transport, and proper ventilation is also designed to keep the electronics cool. The large battery hatch and removable battery bay floor provide easy access to an organized battery and receiver compartment. Grass capable landing gear with suspension struts and 5mm thick steel pin and metal trunion, scale four-panel split flaps, big 16x10 Propeller, 5055-390KV brushless motor, and 80A ESC, LED wingtip lights and dorsal signal light, and 17g digital hybrid servos, brass ball links, and nylon hinges on all control surfaces.

Modifications

Used different types of weathering techniques, changed green camouflage color with a splashing technique to change the look of this model. Added instrument panel and a hand-painted pilot inside the cockpit. Modified landing gear with other tires. Added Spektrum airspeed, flight voltage, and power telemetry. Installed Spektrum 9 Ch with AS3X gyro technology RX. Used a separate UBEC from Castle Creations and an Optipower Ultraguard battery with fail-safe switch PCB. Installed a sound module Aspire from MrRCsound with two TT25 transducers in the radiators on the wings and put in the Merlin Rolls Royce sound and maximized the allowable sound pressure to 84 dBA at 7m distance.

Aircraft Characteristics after Modifications

Scale: 1/7
Wing Span: 1.6 m
Length: 1.3 m
Flight Weight: 4.2 kg
Wing Aera: 44 dm2
Wing Loading: 95 gr/dm2
Wing Cube Loading: WCL 14.4
Power: 6S 5200 mAh
Motor: 1x 5055 KV390 Outrunner
Propeller: 1x 16x10 4-blade
Stall Speed: 42 km/u
Sound Pressure: < 85 dB(A)/7m

Links

Spektrum – Meaningful Telemetry for Airplanes

Videos



Photos

P-47D Thunderbolt

P-47D Razorback - detail frontP-47D Razorback - detail back
After more than three flying seasons, this plane crashed at the beginning of 2020, due to elevator servo disfunction. Because there was a lot of wind and the crash occurred in a field about 150 m from the runway in an allowed flying area a fire destroyed it almost completely. Because this was one of my favorites I will probably configure a new one out of spare parts for season 2021.

The Republic P-47 ‘Razorback’ Thunderbolt was an out­standing fighter, both in the bomber ­ escort and ground-attack roles. It was the largest and heaviest single-engine fighter built during WW2. It was the last in a series of aircraft that began in 1936 with the Seversky P-35 and included the P-43 Lancer in 1940. Common to all these aircraft was their designer, Alexander Kartveli. In the Republic P-47 Thunderbolt, he produced an aircraft that brought the formula to fruition and made up for less successful earlier attempts. A total of 15,634 Thunderbolts were built in several versions. The ‘Razorback', as the first models were called by pilots and ground personnel, was employed intensively by the USAAF and RAF.

This is a highly scaled, lightweight RC-controlled model from FMS. The P-47 Razorback 1500mm adds a slew of innovations to a proven platform. Based on the original 1400mm P-47, the 1500mm model features a 99% scaled control surface, landing gear cover, cockpit interiors, plastic cowling, gun turrets, retracted landing gear, and panel lines. The plane's original oil paint has been replaced by water-based paint. It's built with a lighter and larger EPO 52 foam, making the plane lighter, giving it impressive flight performance without weakening the airplane's strength. New CNC-processed shock-absorbed front landing gear with the latest 2016 FMS electric retract. A new KV650 motor with Predator 70A ESC. All servos are now metal gear digital servos.

Modifications

Used different types of weathering techniques to improve the look of this model. Oracover ironing film on top of the foam to change the look of this model. Added my own Decals inkjet printed on Testors White Decal Paper. Added Spektrum Airspeed, voltage, and Flight power telemetry. Put in Spektrum with AS3X technology 9 channel RX. Used a separate UBEC from Castle Creations and an Optipower Ultraguard battery with fail-safe switch PCB. Installed a sound module Aspire from MrRCsound with two Dayton Audio Exciters DAEX225CT-4 and the Pratt & Whitney R-2800 Double Wasp sound to maximize the allowable sound pressure to 84 dBA at 7m distance

Aircraft Characteristics after Modifications

Scale: 1/7
Wing Span: 1.5 m
Length: 1.3 m
Flight Weight: 4.2 kg
Wing Aera: 38 dm2
Wing Loading: 110 gr/dm2
Wing Cube Loading: WCL 17.9
Power: 6S 5200 mAh
Motor: 1x 4258 KV650 Outrunner
Propeller: 1x 14x8 4-blade
Stall Speed: 44 km/u
Sound Pressure: < 85 dB(A)/7m

Videos


Photos

B-17G Flying Fortress

B17-G Flying Fortress 1
B17G Flying Fortress 2

Second World War Bomber B-17G based on the silver version 2 from HobbyKing with a 1.85 m span. This plane is called “Little Ukkie” and is based on “Chuckie” and “The Short Arm” both planes witch flew In England 1944 with the 486th Bomb Group from the eight Air force, This aluminum colored plane with the Victory sign on the wings bombed strategic sites in Germany and in northern France before D-Day, and after 6 June 1944. The 486th Bomb Group is part of the 834th Bomb Squadron and lost no aircraft or personnel on its first 100 missions. Probably because the allies reached total air superiority over Europe middle of 1944.

Mods

Used different types of weathering techniques and used Oracover ironing film on top of the foam to change the look of this model. Added instrument photo and 2 pilots inside the cockpit and a Norden Bombsight and interior photo in the chin turret. Modified landing gear with other tires. A retractable rear landing gear. Added Spektrum airspeed, temperature ESCs, flight voltage, and power telemetry. Installed Spektrum 9 Ch with AS3X gyro technology RX. Used a separate UBEC from Castle Creations and an Optipower Ultraguard battery with fail-safe switch PCB. Installed a sound module Aspire from MrRCsound with two TT25 transducers and the B17 Multi-Engine Sound to maximize the allowable sound pressure to 84 dBA at 7m distance.

Aircraft Characteristics after Modifications

Scale: 1/17.3
Wing Span: 1.85 m
Length: 1.4 m
Flight Weight: 4,0 kg
Wing Aera: 47 dm2
Wing Loading: 85 gr/dm2
Wing Cube Loading: WCL 12.4
Power: 3S 4400 mAh
Motor: 4x  KV850 Outrunner
Propeller: 4x  10×7 3-blade counter-rotating
Stall Speed: 40 km/u
Sound Pressure: < 85 dB(A)/7m

Links

Spektrum – Meaningful Telemetry for Airplanes
B-17G – Aspire Sound Unit Test

Videos



Photos

MrRCSound – The Aspire Sound Unit Test

Concepts, Electronica, Scale, Plane Aerial Concepts Belgium, Patric Dietvorst, Aspire, B-17G, Flying Fortress, MrRCSound, Multi engine sound

P-47D Aspire Sound Unit - detail

Tested the MrRCSound Aspire module with one TT25 installed in the foam battery compartment of my B-17G Flying Fortress. First I have tested the Aspire Sount Unit in the B-17G with a single Engine file of a 9 cylinder Wright Cyclone motor

Because the Multi-engine sound files of the 9 cylinder Wright Cyclone motors are not available at this moment, I have used the Multi-Engine sound file for the Consolidated B24 Liberator with 4 14 cylinder radial Pratt & Whitney motors.

And also because the TT25 was very hot I have mounted a cooling element on the element and modified the audio output of the Aspire card at about 75 %. Still, the sound pressure is very high, measuring about 97 db A at 1m. The test was successful. I'm satisfied with the result.

More information about this Aspire sound card and TT25 transducer you will find on the website of MrRCSound and in the RCgroups.

www.mrrcsound.com/aspire-info
RCgroups Aspire sound unit discussion

Photos

Landing Gear – Modifications for Grass Fields

 Concepts, Mechanical, Scale, Plane Aerial Concepts Belgium, Patric Dietvorst, AS3X,Eflite, P-47D, Spektrum, Thunderbolt

P-47D Thunderbolt Landing Gear - detail

What makes the best Warbird for grass landing? Something with bigger and particularly sturdy wheels/landing gear. The Eflite P-47D is a tail dragger and with the factory retracts and stock wheels, nose overs are occurring on take off and landings, especially when the grass is not short. A good thing is, the landing gear is wide and there are possibilities to modify the landing gear to improve stability and take flying precautions to successfully take off and land like a scale plane, also on a grass field.

I have exchanged the 2,5″ (5 cm) wheels with Dubro 3″ (7,5 cm) lightweight wheels. It’s possible to retract these wheels. They fit the openings in the wings. Use a copper bus 4-3 mm to adjust the inner diameter of the wheels. Grind away some plastic at one side of the wheel to fit the wide of the wheel on the landing gear.

I change the inclination of the landing gear to use longer bolts and spacers. The wheels are now 2 cm more to the nose of the plane. This makes a real difference.

Take off with Flaps 1/4 out. Give full elevator up before gently apply throttle to get the plane moving. Apply full throttle only when the plane is already rolling through the grass.Take off with a  gentle slope. Retract the landing gear when the plane is airborne. Flaps up when leveling the plane.

Landing with maximum 1/2 flaps deployed, and with a relative fast final approach. (approx. 45-50 km/h). Start losing speed when you are 1m above and at the edge of the grass landing field. Flare when the plane is 50 cm above the field, but keep 10% -15%  throttle so air keeps flowing over the wings and the plane will not tip over. Retract the flaps when you have landed. If you like to taxi, don’t stop the plane first on the grass field. Always taxi with full elevator up and flaps retracted.


Photos

Weathering – To get a real Warbird Look

 Concepts, Plane, Scale, Visualisation Aerial Concepts Belgium, Patric Dietvorst, Eflite, P-47D, Thunderbolt, Vallejo

P-47D Thunderbolt Weathering - detail

These washes from Vallejo come in medium size 35ml Bottles. There are 12 different colors. For this model I have used 505 (Light Rust), 515 (Light Grey) 517 (Dark Grey), 519 (Olive Green), 521 (Oiled Earth). They are water-based and so thin with water. The wash itself is made with an acrylic resin so that the surface tension of the wash behaves like a solvent-based material, but it has the benefits of clean-up and dilution with simple water. The wash itself dries in around 15-20 minutes depending on the temperature and humidity of where you are working with them. You can also layer washes on top of each other as well. You could suffer some light deterioration of the original coat of paint.

I started with the panel lines. With a small paint, the 517 and brush carefully fill only the panel line. Let 2-3 minutes drying, then use a cloth to wipe away some wash. Wipe carefully in the direction of the panel lines. The idea is, less weathering is better and you can always add some more in a second layer.

The second step is washing the olive green surfaces. With a brush paint the  519 and apply this wash on the surfaces. After 30 to 60 seconds wipe most of the wash gentle with a cloth. Repeat if you like more wash. In the middle part of bigger areas, you best remove more to get a lighter effect. If the wash is to dry to remove use a little water or isopropyl alcohol to remove more. On the lighter surfaces at the bottom of the plane use the 515 wash with the same technique.

The third step is to add some details like dark gun strips (517), rust areas, add some chipping with silver acyl paint. Most details you do not wipe with a cloth. Just apply a little and let it dry.

The fourth step is to paint some elements, like paint the machine guns silver, and dry brush the motor part behind the propeller with some silver strips. You can paint the cowl internally black. I have added I yellow tape inside the front of the cowl and use some varnish to fix the tape.

Fifth step. If you finish the weathering and you are satisfied with the result, you can apply a clear varnish by aerosol. Do not overdo because this only adding weight to your model.