E-flite 4-Site 3D FF (Flat Foamy) 800mm PNP: The ultimate guide for buyers

As an enthusiastic RC pilot or ambitious newcomers, you might be looking for a versatile double-decker that allows both sporty flying and challenging 3D art flight maneuvers. The Flat Foamy model of E-flite could be exactly what you are looking for. This comprehensive article highlights all the important aspects of the 800mm Biplane model in the PNP version and helps you make a sound purchasing decision.

Technical specifications and equipment

The E-flite double decker convinces with its sophisticated technical equipment and provides a solid basis for a wide range of flight maneuvers. Here the most important data at a glance:

With this PNP model (plug-and-play), all essential components are already preinstalled. You only need a compatible receiver, a suitable battery and a suitable remote control to be able to cancel.

Customer experiences and reviews

Positive resonance

The feedback from pilots who already fly the Flat Foamy model is mainly positive. The versatility of the aircraft is repeatedly highlighted. An experienced pilot reports: "From gentle cruising to wild 3D maneuvers, this double-decker does everything – and that in a single flight!"

Many users appreciate the robust construction made of EPP material, which remains mostly without serious damage even in the case of inconvenient landings or minor crashes. A customer describes this as "exceptional crash-resistant", which is particularly soothing for beginners in the 3D art flight scene.

The flight properties are also widely praised. The low weight with high structural stiffness at the same time allows precise maneuvering and direct response behavior. An advanced pilot remarks: "Control in all airfields is impressive – be it with slow hovering maneuvers or fast rollers."

Critical votes

However, not all reviews are completely positive. Some pilots report difficulties in strong wind, which is not surprising due to the low weight. "As wind speeds over 10 km/h it becomes challenging to fly precise maneuvers," an experienced user notes.

There is also some criticism of assembly quality. Some customers had to rework to achieve optimal results: "The rudder steering needed some fine tuning to eliminate game and allow precise flying."

Test results and flight performance

Flight time

With a recommended 3S 850-1000mAh LiPo battery, the E-flite 4-Site 3D FF reaches considerable flight times. With moderate flight style, 8-10 minutes can be reached, while intense 3D maneuvers can reduce flight time to about 5-7 minutes. The actual flight time varies depending on battery capacity, flight style and environmental conditions.

Increased power

The specially tuned spectrum external rotor motor in combination with the 30-amp controller offers impressive power reserves. Test pilots report almost unlimited climbing capability – the double-decker can easily rise vertically until it is only visible as a small point in the sky. This power reserve is crucial for demanding 3D maneuvers such as hovering or torque rollers.

Material quality

The construction of high-density EPP (Expanded Polypropylene) with carbon and composite reinforcements proves to be an excellent choice for this type of aircraft. The material is:

• Extreme
• High-grade shock absorbing
• Formally stable even after several crashes
• Easy to repair (with standard CA glue)

The factory-installed digital servos with metal gears on all control surfaces ensure precise reactions and minimize the risk of mechanical defects even when used intensively.

Transportability and storage

The double-decker can be partially disassembled for transport. The support surfaces can be separated from the fuselage, whereby the model can be transported in almost any car. The design with plug-in and screw connections allows quick disassembly and installation on the airfield without tools.

For storage, experienced pilots recommend special foam mounts or a customised transport case to protect sensitive components such as servos and linkages.

Spare parts supply

A great advantage of the E-flite Flat Foamy double decker is the excellent spare parts supply. Horizon Hobby and E-flite offer an extensive range of original spare parts, including:

• Surfaces and hull parts
• Motor carrier and control horns
• Steering parts and small parts
• Replacement motors and servos

In addition, many standard parts such as servos, linkages and screws are compatible with common RC components, which simplifies repair.

Target group and entry barriers

The Flat Foamy model is aimed primarily at advanced beginners to experienced pilots. The difficulty is specified by the manufacturer with Level 2, which means that basic experience in handling RC aircraft is assumed.

The double decker is particularly suitable for:

• Pilots who want to venture into the 3D art flight
• Experienced pilots looking for a versatile and robust training model
• RC enthusiasts with limited space (suitable for indoor and outdoor)

Absolute beginners should first gain experiences with a more stable coach model before moving to this double decker.

Assembly and construction

Time

A great advantage of the E-flite model is the easy and fast installation. In contrast to pure kits, the PNP version is already largely pre-assembled. The final assembly is limited to:

• Mounting of the supporting surfaces on the fuselage
• Installation of the receiver
• Connection of the servo cable
• Adjustment of rudder rudders

Experienced pilots report a time effort of only 30-45 minutes for final assembly – significantly less than the time needed for charging a battery!

Quality of instruction

The accompanying instructions are generally described as clear and comprehensible. It contains:

• Detailed assembly drawings
• Recommendations for focus and rudder deflections
• Tips for first flight and settings
• troubleshooting and maintenance instructions

Some users, however, complain that the guidance is too tight in some details, especially with regard to the optimal setting of the rudder rudder rudder rugs for different flight maneuvers.

Community support

An active community has developed around the Flat Foamy model. In specialized forums such as RCGroups and YouTube channels, there are numerous discussions, tuning tips and flight videos.

Particularly helpful are:

• Numerous tutorials on flight maneuvers specifically for this model
• Setups and programming examples for different remote controls
• Modification suggestions for performance optimization
• Repair instructions for typical damage

These community resources are particularly valuable for beginners who want to benefit from the experience of other pilots.

Alternatives and competitive products

FMS Biplanes

FMS offers comparable double-deckers with models like the "Pitts Special". Compared to the E-flite 4-Site 3D FF, these are distinguished by:

• Mostly slightly higher weight
• Low 3D capabilities
• Often more efficient optics
• Trendy lower price

XK Innovation

The double deckers of XK, such as the A430, offer a more cost-effective alternative with:

• Low construction quality
• Less precise flight characteristics
• Restricted spare part supply
• Significantly lower price

Self-construction alternatives

There are numerous plans for EPP double deckers for advanced craftsmen:

• Significantly lower costs
• Higher time effort
• Possibility of individual adaptation
• Requires special tools and skills

Value for money

The E-flite Flat Foamy double-decker is positioned in the middle to upper price segment for EPP art flight models. Does the performance justify this price?

Most users rate the price-performance ratio as appropriate to good, especially considering the following factors:

• High pre-production quality
• Use of high-quality components (Servos, Motor, Controller)
• Excellent flight properties
• Durable construction
• Good spare parts supply

Price-conscious pilots should, however, bear in mind that additional costs for receivers, battery, charger and remote control are added if they are not already available.

Tips, tricks and optimizations

Flight optimization

Experienced pilots recommend the following adjustments:

• Experiment with different focal points (something head-loader for precision flight, cock-loader for extreme 3D art flight)
• Enlargement of rudder rudders for improved 3D capabilities
• Installation of a more powerful engine for even more thrust
• Use of exponential settings on high and cross-spindles for softer response behavior

Improving durability

To extend the service life, the following modifications have proven successful:

• Enhance critical connection points with carbon rovings
• attaching kevlar strips at particularly stressed locations
• Use of foam adhesive instead of CA adhesive for more flexible repairs
• Installation of landings to protect the underside

Performance improvements

The following tuning options are available for ambitious pilots:

• Conversion to 4S-LiPo batteries (requires adjusted controllers)
• Installation of a lighter receiver for weight reduction
• Adjustment of propeller size for more thrust or longer flight time
• Programming of complex flight phases for different flight styles

Frequent questions and solutions

First flight problems

Question: My model moves strongly to the right/left. What can I do?
Solution: First check the mechanical neutral position of all rows. If this is correct, equalize the tendency by trimming or slight alteration of the side guide mechanism angle.

Question: The engine runs unround or suddenly loses power during the flight.
Solution: Check all cable connections between battery, controller and motor. Frequently, loose plug connections are the cause. Also check the battery for damage and test with another battery.

Repair and maintenance

Question: After a crash, part of the EPP foam is broken. How do I fix it best?
Solution: EPP can be repaired with medium-thin CA glue (cyanacrylate). For larger fractures, the reinforcement with thin adhesive tape or light carbon strips is also recommended.

Question: The rudder distractions have developed game. How can I fix that?
Solution: Replace the Z-Drähte by new or adjust the existing ones. Make sure that the connections to the rudder horns are tight but not too tight.

Optimization and adaptation

Question: Which setup is recommended for beginners in 3D art flight?
Solution: Start with moderate rudder beats (about 70% of the maximum impact) and activate 30-40% exponential function for softer responses to the neutral position. Use a battery with high C rate for constant power.

Question: How can I improve visibility in the sky?
Solution: Attach contrasting color patterns to the underside of the support surfaces. Fluorescent colors or reflective adhesive strips additionally increase visibility. Some pilots also install small LED lights for dusk flights.

Conclusion: For whom is the E-flite 4-Site 3D suitable?

E-flite's Flat Foamy double-decker is geared to ambitious RC pilots who are looking for a versatile, robust and powerful model for entry into the 3D art flight. The PNP version offers an excellent compromise from manufacturing quality and individual adaptation potential.

The model is particularly convincing:

• Easy and fast assembly without special tools
• Versatile flying properties from gentle cruising to extreme 3D maneuvers
• High crash resistance thanks to EPP design
• Excellent spare parts supply

The investment in these double-deckers is particularly worthwhile for pilots who are looking for a reliable training model to develop and refine their art skills. The combination of robustness and performance makes it an ideal companion on the way to advanced 3D pilots.