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Written by Terry Dunn
Horizon Hobby E-flite F-15 Eagle 64mm EDF BNF Basic with AS3X and SAFE Select
Review
As seen in the September 2019 issue of Model Aviation.



With SAFE engaged, the F-15 is fast but docile. It becomes much more maneuverable with SAFE disabled.

THE F-15 EAGLE is a legendary fighter. It is a fast and nimble jet that has been in service for nearly 45 years! During that time, this twin-engine pugilist has gone undefeated—racking up more than 100 air-to-air victories without any losses.

Although many modelers would love to have their own downsized F-15, any model of the Eagle is potentially complex and challenging to fly. That is not the case with the new F-15 Eagle electric ducted-fan (EDF) model from E-flite. It has a simple, lightweight layout that will be familiar to most sport pilots. The BNF version of the Eagle even offers electronic stabilization to help you get this speedy airplane off the ground and around the patch.

About the E-flite F-15

The E-flite F-15 features molded-foam components that are factory painted in a unique camouflage trim scheme. The moderate-size jet has a wingspan of slightly more than 28 inches and is 38.6 inches in length. The full-scale Eagle is propelled by two massive, fuel-burning jet engines, but this mini doppelganger uses a single 64 mm diameter EDF. The solo fan unit is a major element of this model’s elegant simplicity, but it still has plenty of "oomph!"

Another factor contributing to the F-15’s simplicity is the landing gear. This model is large enough that it certainly could have been outfitted with retractable landing gear, yet that likely would have incurred significant penalties in weight, complexity, and cost. The included setup, consisting of fixed, removable landing gear, is a reasonable compromise.

There are two available versions of the E-flite F-15: the BNF Basic and a Plug-N-Play (PNP) iteration. The only difference between the PNP and BNF variants is that the BNF includes a Spektrum AR636 receiver with SAFE Select stabilization. This receiver can be linked to a DSM2/DSMX-compatible transmitter with five-plus channels. PNP owners must provide their own receiver and transmitter with four-plus channels. This review covers the BNF model.

SAFE stabilization found on the BNF model is intended to make flying the F-15 more manageable by auto-leveling the aircraft when the pilot releases the control sticks. It also limits the model’s maximum pitch and roll angles. SAFE can easily be enabled or disabled, so you can fly with a helping hand or completely unassisted during any portion of a flight.

Both versions include the aforementioned EDF with a 3150 Kv outrunner brushless motor and 40-amp ESC. All of these components are factory installed. You must provide a four-cell 2,200 mAh LiPo battery to complete the power system. There are also five Spektrum A330 servos installed throughout the airframe. Two servos command the ailerons, two are attached to the elevators, and one controls the nose wheel steering.

Assembling the F-15

The F-15 is mostly prebuilt, but there are a few minor assembly steps to complete. If you decide to use the landing gear, it must be bolted into place. Each main gear is sandwiched in place with a plastic plate held with two screws. The steerable nose gear gets attached to a short stub using a coupler with setscrews.

fuel tanks and missiles
The included fuel tanks and missiles can be easily installed or removed at the field without tools.

the f-15 is mostly factory
The F-15 is mostly factory built and comes in a three-color paint scheme.

If you prefer this model as a belly-lander, you will need to uninstall the nose stub by removing the horn from the steering servo under the canopy. There is no need to commit to a firm decision on the landing gear. The installation/removal process is simple and quick enough to tackle at the field.

Removable wing panels slide into place over a carbon-fiber spar and are secured with machine screws. You then connect the aileron servos to the exposed plugs. Color-matching decals are provided to conceal the servo plugs and wires.

The horizontal and vertical stabilizers are adhered to the fuselage with CA adhesive. For each connection, I applied a thin layer of medium CA glue to the relevant stabilizer and a mist of activator to the mounting area. All of the parts fit into place easily and were perfectly aligned.

battery and landing gear configurations
The author devised a simple method to vary the amount of tail weight to accommodate different battery and landing gear configurations.

carbon fiber spar
The removable wing panels use a carbon-fiber spar and are held in place with screws.

Removable ordnance is included in the form of external fuel tanks and sidewinder missiles made of foam. Two missiles are bonded to each fuel tank with medium CA. Plastic posts on the tank pylons interface with mating slots on the bottom of the wing. No tools are required to install or remove these items.

I linked the receiver to my Spektrum iX12 transmitter. During this process, I was able to choose whether to have SAFE stabilization activated with a switch or completely disabled. I chose to retain the SAFE option and configured the system to activate stabilization with a two-position switch.

I use a Kinexsis four-cell 2,200 mAh LiPo battery with a 40C discharge rate. A unique feature of this battery is the built-in charge indicator. Simply push a tiny button on the battery and a colored LED will illuminate to tell you the approximate charge state. Clever!

Although my battery had ample room in the Eagle’s battery compartment, cluttered wires made it slightly difficult to install and remove. I rearranged the wires to my liking and secured them with zip ties.

Balancing the F-15 involves a few variables. With the landing gear installed and the 4S 2,200 LiPo battery fully rearward, my Eagle required 3/4 ounce of ballast in the tail to get within the recommended center of gravity range. This model can also be flown with a three-cell 2,200 mAh LiPo battery. The amount of necessary ballast varies with the chosen battery and whether the landing gear is installed.

At A Glance

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Specifications

Type: Semiscale EDF

Wingspan: 28.2 inches

Wing area: 551 square inches

Length: 38.6 inches

Radio: Spektrum iX12 2.4 GHz transmitter; Spektrum AR636A receiver (included); five Spektrum A330 submicro servos (included)

Needed to complete: Five-plus-channel DSM2/DSMX transmitter; four-cell 2,200 mAh 30-plus C LiPo battery; charger

Minimal flying area: Club field

Power system: 64 mm 11-blade EDF unit with 2840-3150 Kv brushless motor (included); E-flite 40-amp ESC (included); Kinexsis 4S 2,200 mAh 30C LED LiPo battery

Power output: 43.4 amps; 616 watts; 280 watts per pound

Flying weight: 34.4 ounces

Flight time: 3 to 4 minutes

Price: $179.99 BNF; $159.99 PNP (does not include receiver)

pluse symbol

Pluses

  • Speedy, predictable flight performance.
  • Great-sounding EDF.
  • Easy hand launches.

minuses symbol

Minuses

  • Challenging visual orientation.
  • Significant difference in control response with/without SAFE enabled.
  • Limited taxiing agility.

manufacturer distributor symbol

Manufacturer/Distributor

Horizon Hobby/E-flite

(800) 338-4639

www.horizonhobby.com

e flite
E-flite’s F-15 captures the menacing look of the famous, full-scale jet fighter.

I addressed the ballast issue by adding a thin strip of 1/32 plywood behind each of the EDF exhaust cones. I drilled a small hole though the center of a few 1/4-ounce weights. Using #2 × 3/8-inch screws through the weights and into the plywood, I can attach up to four individual weights as required to balance each battery/landing gear configuration. I painted the plywood and weights white to make them less noticeable.

Flying the F-15

My initial flights with the F-15 were made with the landing gear installed. I immediately noticed that the nose wheel steering has limited movement. It is fine for takeoff, but the Eagle’s lack of agility on the ground made taxiing challenging.

With more than 600 watts of power on tap, the Eagle builds speed quickly and tracks well on takeoff. A little back pressure on the elevator will lift the nose and get the airplane airborne with a rapid climbout.

With SAFE enabled, the model is very stable and predictable. Pilots who are nervous about stepping up to a speedy EDF will likely appreciate this artificial stability. Conversely, experienced jet jockeys might find it disconcerting. It requires large control inputs to simply get around the pattern. I sometimes found myself practically bending the control sticks and using body English to get the F-15 through a reasonably tight turn.

There is a huge shift in control authority as soon as you deactivate SAFE. The airplane responds to inputs in a more fighter-like fashion and enjoys a light touch on the controls. Disabling SAFE also opens the door to a selection of aerobatic moves. The Eagle has good aerodynamic stability, so reasonably experienced fliers should have no trouble handling the model with SAFE disabled. Most of my flight time on the F-15 has been "SAFE-less."

Although I consider myself a competent pilot, I still like to keep SAFE in my back pocket. It makes hand launches completely stress free. All I have to do is power up the motor and give the airplane a reasonable toss. SAFE ensures that the Eagle departs at a good flight attitude and I don’t have to scramble to get both hands on the transmitter. Then I turn off SAFE and cut loose with the Eagle.

I set up my model with the suggested control throws and also added 35% exponential. High-rate aileron rolls are fast and crisp. Elevator authority is less snappy, but still adequate. I’ve found that I prefer to fly with low-rate ailerons and high-rate elevator.

The 11-blade fan unit sings a pleasant note and provides impressive vertical performance. Loops can be large and round if you want. Inverted passes look great, but they require a healthy input of down-elevator.

I really like the color scheme. The only downside is that in-flight orientation can be challenging. The shades of blue and gray sometimes blend with the sky. Additionally, there is no difference in color between the top and bottom sides of the airplane. It is manageable but requires a steady eye.

Even with the landing gear and ordnance installed, the F-15 is clean, fast, and retains energy well. Be sure to plan your landing approach with enough time and airspace to bleed off speed. It flares nicely for a rolling arrival on the runway or a belly flop in the grass.

There is a significant decrease in power when flying with a three-cell battery. The model, however, is still quite sporty. With that noted, I definitely prefer the extra headroom afforded with a four-cell powerplant. I configure my flight timer for 3 minutes and set up for landing as soon as it buzzes. If you’re the type to linger in "afterburner," you will probably want to be on the ground at the 3-minute mark.

Final Approach

The simplified design of E-flite’s F-15 BNF makes the famous jet fighter accessible to thrill-seeking sport pilots. The single fan unit offers a surplus of power with a simple layout and common, affordable batteries.

SAFE stabilization can help ease pilots into the fast lane and lower everyone’s blood pressure when hand launching. Without SAFE, the Eagle is a nimble aerobat. It is a well-designed model that never fails to get the adrenaline flowing.

as3x and safe select

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