Horizon Hobby E-flite UMX Citation Longitude Twin 30mm EDF Jet

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Written by Terry Dunn
Pilot’s Choice Product Review
As seen in the Fall 2020 issue of Park Pilot

SPECIFICATIONS:
Type: Ultramicro scale EDF
Wingspan: 25.1 inches
Wing area: 83 square inches
Length: 24.9 inches
Radio: Spektrum iX12 2.4 GHz transmitter; Spektrum receiver/ESC unit (included); 
five long-throw linear servos (included)
Components needed to complete: 
Five-plus-channel DSM2/DSMX transmitter; 
3S 800 mAh 30C LiPo battery and charger
Minimum flying area: RC club field
Power system: Two 30 mm fan units with 8,800 Kv outrunner brushless motors (included); E-flite 3S 800 mAh 30C LiPo battery
Power output: 10.3 amps; 107 watts; 
252 watts per pound
Flying weight: 6.8 ounces 
Wing loading: 11.8 ounces per square foot
Flight time: 5 to 6 minutes
Price: $169.99
Info: horizonhobby.com

Features:
>>  Functional features include LED navigation/ landing lights plus a full-flying stabilizer
>>  More powerful 3S-compatible outrunner motors and larger-diameter 30 mm fans
>>  Lightweight yet durable composite-reinforced airframe and nose
>>  Removable landing gear with steerable nose wheel

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The Citation Longitude comes out of the box completely built and ready to bind to your DSM2/DSMX transmitter.

>> The Cessna Citation Longitude is a brand-new, eight-passenger business jet with a range of more than 4,000 miles. It is the latest iteration of the Citation series that was first launched nearly 50 years ago. This luxurious fast mover is not for the miserly. The sticker price of a factory-fresh Longitude is a cool $27 million.
E-flite’s ultramicro adaptation of the Citation Longitude is significantly smaller in both size and price. The molded-foam airframe has a wingspan of slightly more than 25 inches and weighs less than 7 ounces. It is available as a BNF (Bind-N-Fly) Basic model for $169.99.
This model accurately recreates the sleek profile of a full-scale Longitude. Plastic detail pieces, such as winglets, add nice visual accents without being fragile. Chrome inlet rings on the ducted fans are a particularly cool feature.
A combination of stickers and paint is used to create the factory-applied trim scheme. My example looks very good, with clean, well-defined paint borders. The stickers are nicely centered and there are few wrinkles. Bright navigation and landing lights help to complete the scale illusion.
This model is completely factory assembled. In fact, you might have to do some disassembly to prepare the Citation for flight. It includes removable landing gear (with a steerable nose wheel) that is preinstalled. I removed the gear because my initial flights were at a grass field that necessitated hand launches. No tools are required to install or remove the gear.

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Removable landing gear allows a pilot to hand launch or use a paved runway for rolling takeoffs.

The only mandatory prep work involves radio setup. You will need to configure a model profile in your Spektrum DSM2/DSMX transmitter (spektrumrc.com) and configure it per the table in the Citation’s manual. I used a Spektrum iX12 transmitter.
Be sure to check the E-flite website for any updates or addendums to the manual. I was having some difficulty getting all of the controls to work correctly until I discovered an addendum about configuring the AUX1 channel.
The onboard radio gear consists of a DSM2/DSMX-compatible receiver with dual brushless ESCs. The receiver also has two built-in linear servos that actuate the rudder and elevator. Two separate linear servos drive the ailerons.
One feature that I found interesting is the Longitude’s full-flying elevator. In other words, the entire horizontal stabilizer swivels up and down to provide pitch control. The overall setup works well, but the hinge on my unit is somewhat loose. This results in the elevator having a noticeable amount of play in the roll axis.
Like most ultramicro models in E-flite’s lineup, the Citation has AS3X and SAFE Select stabilization. AS3X makes constant miniscule corrections to keep the airplane on a smooth flight path in windy conditions. When activated, SAFE Select limits the airplane’s maximum pitch and bank angles, while also providing automatic recovery to level flight when the control sticks are released.
Whereas most ultramicro models are powered by one-cell or two-cell LiPo batteries, the UMX Citation raises the voltage with a three-cell 800 mAh 30C LiPo battery. It is secured to the internal battery tray with hook-and-loop tape. A large, magnetically secured hatch in the top of the fuselage provides easy access.
This micro business jet is propelled by a pair of 30 mm diameter EDFs (electric ducted fans). Tiny 8,800 Kv brushless motors spin the six-blade rotors. These EDFs are small, but they generate an impressive amount of thrust for the Citation.

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Power is provided by a 3S 800 mAh LiPo battery. Note the large access hatch.

At full throttle, the propulsion system pulls 10.3 amps and produces 107 watts. That’s a superb amount of power for a model of this size and weight. My only concern is that the included JST battery connectors are being overstressed in this application. Although I never experienced any problems with the stock connectors, I eventually replaced them with XT30 connectors, which can handle considerably more power.
My Citation Longitude balances at the suggested center of gravity location with the battery placed near the rear of the tray. Prepare yourself when you plug in the battery. The arming tones emitted by the motors are shockingly loud. They’ll make you jump!
I prefer to hand launch the Citation with SAFE engaged. This ensures that the wing stays level until I can get both hands back on the transmitter. There is plenty of thrust available, so you only need a light underhand toss to get the model airborne.

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The 30 mm EDF units are small, but they produce tremendous power to propel the Citation.


Be sure to launch the Citation at a slightly upward angle. After release, the airplane will slowly nose-over in an arc until the elevator grabs air and becomes effective.
Rolling takeoffs are easy as well. The steerable nose wheel provides positive control on the ground. You can slam the throttle forward and yank the Citation off the runway after a short roll. Longer, gentler departures are equally simple and more pleasing to watch.
When airborne, the Citation quickly accelerates. This thing can really move! Keep that in mind when choosing a flying site. Be sure to give yourself plenty of room to maneuver. A single soccer field probably won’t cut it.
Disabling SAFE makes the Longitude fully aerobatic. There is a lot of thrust available for big vertical maneuvers. The ailerons provide crisp roll response. You can even include a quick jab of rudder and elevator to induce a violent snap roll—not a maneuver you typically associate with business jets.
The full-flying elevator provides good pitch authority. Just a hint of forward pressure on the stick is necessary to maintain inverted flight.
The rudder is surprisingly effective as well. This jet will hold a rock-steady knife-edge pass from one edge of the field to the other.
Do you recall the loose elevator hinge that I mentioned earlier? You can actually see the elevator become misaligned during flight. In fact, the elevator is rarely parallel with the wing when viewed from the front.
The good news here is that this intermittent misalignment of the elevator seems to have no detrimental effect on the airplane’s controllability. It remains locked into its flight path and responds to inputs with no surprising deviations. I suspect that the AS3X stabilization helps here.
I have flown the Citation on gusty days. This pointy little model penetrates the wind well. Despite its relatively light wing loading, it tracks predictably in these conditions. I believe this is another example of the benefits of AS3X in ultramicro models.
I am not usually the type of pilot who keeps the throttle firewalled for most of a flight, but I’ve found that the Citation brings out that side of me. It’sjust that this airplane is a lot of fun to throw around, doing low passes, vertical climbs, and high-G turns—I can’t help myself.
Although there is a lot of fun to be had at full throttle, the Citation also performs well at lower power settings. Even half throttle is sufficient to keep the model moving with adequate speed for solid control.
Most of my flights last between 5 and 6 minutes. The motors pulse when the battery gets critically low. Make sure you head for the runway when that happens!
The Citation retains energy well, so be sure to plan your landing with a nice, long approach. The airplane lands easily whether using the landing gear or sliding in on its belly.
E-flite’s rendition of a modern business jet is not for newcomers. Even with SAFE engaged to keep the wing level, this airplane is simply too fast and responsive for beginner pilots. But for those who crave speed and nimble aerobatics in a small, classy-looking package, the UMX Citation Longitude delivers. It is an attractive airplane with exciting performance.

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The UMX Citation Longitude is fast and aerobatic.

By Terry Dunn | terrydunn74@gmail.com
Photos by Terry Dunn and Mark Gustas

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