The F3H Demon was the father of the F-4 Phantom.
This all weather fighter was designed beginning 1949 by Mc Donnell Aircraft Corporation in St Louis and was very advanced for its time.
The very unique inlet/ belly/ nose shape was derived from a NACA study from 1947 by Mark Nichols and Edwin Goral.
The aircraft entered service in the Navy in 1956, The delay was due to the unreliale Wesington engine that pushed Mc Donnell to re-design the airframe for the Allisson J-71. The aircraft missed the Korean war due to this problem.
Our Demon is a tribute to the genius of Mc Donnell design teams.
The model was CAD designed from blueprints and pictures provided by our friends Mark Frankel and Mark Nankivil. It was CNC cut from our high precision Kuka milling robot and routes and is extremely true to scale.
The wing and stabilizer airfoil were adapted to lower Reynolds number from the original airfoils.
The airframe is built from our new ultra light weight MILtech material. This consists of several layers of MIL spec 0.6 oz uni directional carbon fiber vacuum cured with MIL spec ultra light weight 40 kg/ m3 PEI core material and aero spec epoxy resin vacuum sandwich. Post curing to 100c allows extremely high temperature resistance.
The surface detail is extremely realistic with every panel and stringer represented as well as the stressed skin wrinkles. Lots of scale details of the plane were reproduced under the guidance of Mark Frankel, our scale "guru". The entire plane was plated with CNC machined aluminum panels.
The plane has been the object of extensive CFD research. All airfoils were derived from Michael Selig's data base and modified to the airplane operating Reynolds numbers as well as leading edge slats operations.
This ensures very nice flying characteristics with virtually no tendency to snap stall at low speed. The flaps and slats are very effective and allow to slow the plane down considerably. All controls have aerodynamic seals.
We also spent a considerable amount of time working on the compacity of the plane for shipment. The fuselage splits in 3 parts. Nose section, center section and beaver tail. The stabilizers and fin are removable. This allows to ship the plane in a very compact box that can be carried as airplane check in luggage, which we did for Jet Power 2019:
The airplane ergonomics was also very carefully elaborated at the CAD design stage.
A long engine hatch is available on the top of the center fuselage section. This allows easy access and removal of the front intakes and rear titanium/ carbon thrust tube. The large canopy is removable as a single piece with the cockpit tub. This opens up a large area to access the nose gear bay, landing gear controller, battery compartment and engine anciliaries section. A large hatch is made at the bottom of the beaver tail section and allows access to all the tail section servos. From this hatch, fin and stabilizers can be removed by un-fastening one screw. The wings are fastened in position with one screw easily accessible from the main wheel bay. The radome is 1/4 turn type and allows access to the receiver tray. This slides forward with 2 screws. A secondary accessories tray is located above the main receiver tray. This one slides aft into the cockpit bay and carries the gear controller, ECU and gear batteries, gyro and telemetry box if required.
Access to the remote control system and accessory is very easy as well:
F3H-2 radio tray demonstration from Oli Ni on Vimeo.
The rigidity of the plane was carefully considered. The full carbon fiber wings are extremely stiff. A Finnish birch aircraft plywood structure is holding the main gear and wing tubes. The 2 carbon wing tubes are single piece across the fuselage, and made in-house from shock resistant carbon fiber. The tail section is tripe laminated with biaxial carbon fiber at +- 45 degrees to maximize the twisting stiffness of the area. A solid carbon fiber structure holds carbon servo trays and the full alloy stabilizer bearing block. Flight controls:
All the controls have integrated horns and pushrods. No control link is visible.
The ailerons, flaps, slats, stabilizers and rudder are controlled by one servo placed close to their surface. All the pushrods are kept super short. All the controls use aero spec M3 metal ball links and stainless pushrods.
A total of 4 bearings hold the stabilizer shafts. Two of them are super stiff and wide needle bearings. The shafts are slotted and the custom servo arms keyed to prevent any unwanted rotation of the stabilizers in the arms.
The rudder is plug-in type and has a torque rod slotting into the bottom of its moving section. The torque rod is guided by two large brass bushings.
Fuselage speed brakes and wing spoiler plates are available as scale accessories.
The scale landing gear includes custom designed electric retracts, custom CNC machined/ 3D printed struts and wheel, electric brakes and direct servo steering.
The retract controller is the well proven LG15, custom programmed for this airplane.
Easy access to the gear controller is available from the canopy opening.
The engine is installed in a full carbon bypass. The intake is kevlar fiber made, whereas the tail pipe is our World famous titanium/ carbon fiber system that is designed to create a low pitch growl at full thrust for more realism.
The thin side inlets are suitable for engines up to 140N without blow-in doors. Above this thrust level, the scale doors are required to help reducing the vacuum generated in the bypass.
The entire internal air duct system is designed according to the best thermal management practices and the plane runs really cold in all conditions.
At the field and flight characteristics:
The plane is extremely easy to set up.
Fuselage with stabs and fin fits in one piece in most SUV.
Just plug the wings in, connect one USC 20 plug per wig, fasten 2 screws, , refuel and that's it!
Thanks to the extensive CFD and structural study, the plane is extremely slick in flight. The gliding ratio is impressive and the plane behaves very much like a big glider.
The F3H-2 exhibits good aerobatics abilities and is very capable in inverted maneuvers.
Landing is easy thanks to the big wing, wide landing gear stance, slats and ground high pitch attitude.
F3H-2 Demon flight 6 from Oli Ni on Vimeo.
Ordering:
A wide variety of schemes is available on this plane.
From day-glow training versions to standard Navy schemes and flying target high visibility painting.
A number of work packages can be purchased with the base kit, to bring it up to turnkey.
Work package 1: Servos and flight controls installed and connected. Servos centered to 150 ms.
Work package 2: Landing gear and doors installed and tested.
Work package 3: Fuel system and engine installed and tested
Work package 4: Paint scheme and squadron markings applied to the plane. Does not include nomenclature.
The following options are available:
- Ultra scale electric landing gear
- Kevlar fuel tank of 4 liters
- JWM soft fuel bladder of 4 liters
- Full carbon fiber engine bypass
- Carbon/ titanium thrust tube
- Ultra scale cockpit
- Gear door liners and actuation package
- Fuselage speed brake
- Wing spoilers
- Under wing pylons
- Cruise underwing tanks
- Sidewinders
- Sparrow missiles
- Refueling probe
- Custom CNC cut MDF/ matt black painted stand
Airframe specifications:
Scale 1/7
Length: 2.54 m
Span: 1.54 m
Height: 0.64 m
Dry weight: 14 to 15 kgs
Takeoff weight: 17 to 18 kgs
Recommended engine: 140 N
