The
MaxFlight F5K is an innovative 1.5m electric DLG type glider with two piece wings. With great performance and forgiving flight characteristics this may be the most advanced F5K model we have seen so far.
The outstanding benefits of this model are:
- Well thought out design intended for electric flight from the outset - not a modified discus launch glider.
- Excellent glide performance and good speed range.
- Lightweight carbon all molded construction.
- Superb surface finish and attractive colour schemes.
- Two piece wing and easy to dismount the fin and tailplane make for a very easy to transport model in a box just 86 cm (34") long.
- Large canopy hatch for east access to the motor, ESC and battery.
- Available in 4 servo (flaperon) and 6 servo (aileron and separate flap) versions.
- Preinstalled mounting system for 4 KST X08 tail and wing servos under the wing.
- Large under-wing hatch for access to the fuselage servos.
- Easy and quick assembly at the field.
The wing is beautifully molded from spread carbon with a Rohacell core to maximise strength and dimensional stability, ensuring the surface finish stays smooth. The wing is available in two versions:
Flaperons - a single control surface on each wing, actuated from fuselage mounted servos, is used both for roll (aileron) and flap/camber, as used successfully on DLGs. This has the advantage of simplicity and not needing any wing mounted servos, reducing the cost. Also only a 5+ channel receiver is required and transmitter programming is simplified.
Separate Ailerons and Flaps - two control surfaces on each wing. The inner flap control surface is actuated from fuselage mounted servos, and the outer aileron control surface is mounted by an outboard servo. This has the advantage allowing much greater flap deflection during landing, giving better control and slower touchdowns - potentially allowing the model to be flown from a smaller field. A 7+ channel receiver will be required and transmitter programming is a little more complex.
The fuselage is a one piece design with a generous front to facilitate fitting a small powertrain and four servos. A firewall is supplied but not fitted, to allow it to be recessed as appropriate for the motor used. The tailplane (horizontal stabiliser) and fin (vertical stab) are very light and have a good finish. The rudder and elevator are ready hinged and give good control response.
The fuselage is supplied with a servo deck pre-cut for 4 pcs KST X08 servos. The supplied accessories include a firewall, servo mount, all pushrods, rudder and elevator pull cables, torque springs, and all control horns. The wings are supplied in thin foam bags but fit nicely in our
DLG F3K Wing Bags for greater protection.
| MaxFlight F5K Specifications |
|---|
| Wing span |
1.5 m |
59 in |
| Wing area |
18.8 dm2 |
291 sq in |
| Length inc spinner |
87 cm |
34.3 in |
| Flying weight from |
270 g |
9.5 oz |
| Wing loading |
14.4 g/dm |
4.7 oz/sq ft |
| Aspect ratio |
12.0 |
| Wing airfoil |
Special 7% |
| EDA (dihedral) |
6.0º |
| Spinner Diameter |
25 mm |
| Centre of Gravity |
61-65 mm from wing leading edge |
| Controls (4 servo version) |
Rudder, elevator, ailerons, throttle |
| Controls (6 servo version) |
Rudder, elevator, ailerons, flaps, throttle |
The powertrain used in the photos gave closely folding prop blades to minimise drag. The items used were as below, however a
VM Powerset will also work well.
| MaxFlight F5J 6 Servo Control Throws |
|---|
| Rudder |
12 mm each way |
| Elevator |
8 mm up / 6 mm down |
| Ailerons |
8 mm up / 5 mm down |
| Flaps (roll) |
Flaps follow ailerons |
| Flaps (landing) |
40 mm down (6 mm down elevator with full flap) |
| Camber Settings |
| Speed |
Flaps 2 mm up, ailerons follow flaps |
| Cruise |
0 mm |
| Thermal |
Flaps 4 mm down, ailerons follow flaps |
| MaxFlight F5J 4 Servo Control Throws |
|---|
| Rudder |
12 mm each way |
| Elevator |
8 mm up / 6 mm down |
| Ailerons |
11 mm up / 7 mm down (at wing root) |
| Ailerons (landing) |
25 mm down (4 mm down elevator with full flap) |
| Camber Settings |
| Speed |
Ailerons 2 mm up |
| Cruise |
0 mm |
| Thermal |
Ailerons 4 mm down |
| MaxFlight F5K Typical Weights - 4 servo version |
|---|
| Fuselage |
36 g |
1.3 oz |
| Wings |
97 g |
3.4 oz |
| Tailplane |
10 g |
0.4 oz |
| Fin |
7 g |
0.2 oz |
| Wing joiner |
10 g |
0.4 oz |
| Accessories & glue |
10 g |
0.4 oz |
| Total structure |
170 g |
6.0 oz |
| Receiver |
6 g |
0.2 oz |
| Rudder servo |
8 g |
0.3 oz |
| Elevator servo |
8 g |
0.3 oz |
| Wing servos (2) |
17 g |
0.6 oz |
| ESC |
5 g |
0.2 oz |
| Motor |
20 g |
0.7 oz |
| Prop & spinner |
6 g |
0.2 oz |
| Battery |
30 g |
1.1 oz |
| Flying weight |
270 g |
9.5 oz |
(C) 2021 Neil Stainton
