Align T-REX 550X Dominator Review


The last T-REX model I owned was the T-REX 550V2 back in 2019. That model turned a lot of chapters for me with my build and flying ability. Though it had a flybar it was still stable and flew much like a bigger helicopter. I have setup a few Align models since for some guys but have not owned one in over four years so I looked forward to trying out the new 550X. The T-REX 550X is definitely a leap forward in performance than past 550 models with the integration of numerous innovative design changes and overall lightweight improvements.

Align was one of the first originators when it came to electric 3D model helicopters in the early 90s with their 450 size models. They have had a very successful line of helicopter sizes from 250-800 class machines. All sporting flybar and flybarless technology is offered in both nitro and electric models. If you are just starting out in the hobby and want something reliable that won’t break the bank Align has a model for you. I think if you ask most guys what their first model kit build was they would say it was an Align. Besides Blade with their RTF/BNF helicopters, I strongly believe Align is a contributing factor for a lot of newcomers in the hobby both past and present.


When you open the box you will find numerous marked boxes containing all of the different sub-assemblies. The first box I opened included the skids, fin, and some frame parts as well as the new 550X canopy. The canopy is nicely painted in a red, white and blue Align color scheme with a nice clear coat finish. Depending on the 550X package you purchase you will find all of the electronics in their own separate box. The main rotor box has all of the head parts and remaining components to build the helicopter with the sub-assemblies set preassembled and packaged in their own sealed bags. The frame sides are sitting at the bottom of the box with the manual and the remaining box contains the blades, tail boom, boom


The build begins by assembling the EFL Flybarless Rotor Head System. It comes completely dry assembled so you will need to completely break it down and reassemble with loctite and grease. The EFL head design was developed to utilize extreme low CG to effectively reduce resistance during 3D maneuvers while increasing flight responsiveness and precision. Thus increases the usable rotor RPM range without having to change the rigidity of the dampening system. This allows for an optimal control of the geometry even when large amounts of torque are introduced into the system. Some of the head parts are accented with a nice red anodizing on the stainless precision machined metal parts. Align has also redeveloped the swashplate. Their new advanced metal swashplate firmly connects to rotor grips preventing rotor head disengagement during intense flight. Two linkage ball mounting holes provide improved control of system movement. Once I had the head and swashplate assembled I installed them onto the main shaft to await installation into the frame.

The T-REX 550X main frame utilizes composite material integration technology on the carbon side frame plates, including the addition of battery mounting side rails and a top motor mount design. In addition, the T-REX 550X's lightweight design is 200g lighter than on previous 550 models. The 3K main frame feature embedded battery mounting rails and a latch design which provide quick battery changes. The two frame halves join together with M3 screws sandwiched between bearing blocks, frame standoff posts and the front plastic electronics tray. Align integrates plastic parts on the frame to give the model a unique look and cover some parts that may have electronic wires cross over or through parts of the frame. The 550X uses Align’s traditional skid and pipe landing skid design that mounts onto the lower frame standoffs. On the new 550X model the rear landing skid is taller giving the model a 5 degree forward tilt to keep the tail higher off the ground.

The tail boom and tail assembly follows suit to most torque tube pod and boom models on the market today. The front plastic tail boom mount has your front drive gear along with the front umbrella gear. The tail case assembly is made up of an aluminum tail tube case with torque tube gears and metal side plates. Manufactured with stronger material, the torque tube front drive gear is more durable. The stronger material reduces the probability of gear striping during flight or damaging the gear as a result of a crash. The newly designed dual point supported tail pitch assembly delivers slop free performance while improving rudder control and precision. The carbon tail boom is built from 3K carbon fiber and aluminum imbedded technology which features light weight and high strength. I’ve flown belted helis the last 4 years so it felt weird assembling a torque tube model again with the inner boom bearing and rubber keeper. Once the torque tube assembly was installed I assembled the rest of the tail components onto the boom. With the tail assembly complete (tail boom case, tail case, boom supports, fins and pushrod) I installed the rear tail section and boom supports onto the main frame using the provided M3 screws.

Next I assembled the main 112T CNC slanted main gear which make for a very efficient and strong drive system. With the main gear and autorotation gear complete I slid it inside the frame and lowered the head assembly down inside of it and secured the main jesus bolt. With the airframe complete it was time to setup my electronics and install them onto the airframe. With all my builds I have the electronics all soldered up and servos centered in the FBL system before I begin my builds. This makes the next step of the build go much quicker.


For my T-REX 550X build I chose to use the MKS HBL950 high voltage servos on cyclic and a MKS HBL950 for tail control. After installing the servos I routed my wires up towards the front of the frame and secured them using small black zip ties. As previously mentioned I always plug in my servos and center the servo arms before I install the servos onto the frame making the setup steps go much quicker. I decided to use the provided Align motor and mounted it onto the aluminum motor mount and slid it into the frame and secured it into place leaving some little pinion backlash. The T-REX 550X uses the new powerful 730MX (960KV) motor which is highly efficient providing superior power while improving the performance of the 6S power system. You can now adjust the motor pinion main gear mesh. You don’t want it so tight to stress the motor but if it’s too loose it could slip and strip the main gear.

I mounted the Castle Talon 90 onto the right side of the front plastic electronics tray. This location is perfect on the 550X as the wires from the motor can plug directly into the ESC. I mounted the NEO flybarless unit with the wires facing back on top of the front electronics tray. Having everything on the front of this model gives the rear of the 550X a nice clean look when the canopy is installed. However you can choose to mount your FBL system and receiver on the rear of the model on the tail boom mount as well as with past models. I mounted a Scorpion Backup on the left side of the front tray opposite the ESC. The 550X is very spacious and gives you a variety of locations for mounting the model’s electronics. Setup with the Mikado Vbar Control radio and NEO flybarless system was extremely fast and EASY. When you are setting up a new “Other 600” model in the NEO wizard it automatically puts basic presets in the NEO leaving the builder just a few quick setup steps to get your model into the air!


After a quick circuit around the field to run the NEO flybarless system through its initial setup test flight it was time to run the T-REX 550X through its 3D paces. The 550X tracked perfectly through the corners, with noticeably higher control precision then the 550L DFC model before this. It’s collective and cyclic response were quick yet agile. Stationary flips and rolls are fast and stable, with no noticeable wobbles and tic-tocs were crisp and precise. The bright red, white and blue canopy was extremely easy to see in all orientations. I can remember back a few years ago my maiden flights used to be hovering around, a few pitch pumps and some forward flight to check tail gains. With today’s quality helicopters and the Mikado NEO setup wizard getting you so close to a perfect flying setup you can run the model through its 3D paces on its maiden flight.

Flight mode Throttle RPM
Bank 1 Governed 1950
Bank 2 Governed 2150
Bank 3 Governed 2350

I purchased Pulse Ultra 4100 mAh 45C packs for this model to keep the weight down for harder 3D flight. If I want to just have fun and sport fly I sacrifice some weight performance but gain minutes of flight time using Pulse 5000 and 5500 mAh packs. My recommendation is lean towards 4500-5000mAh packs if you plan on flying aggressively. You could even get more flight time if you optimize your power system to run at a lower headspeed.

For soft sport flying the 550X really flies well at 1800-2000rpm with zero bobble and really extends your flight time. I tend to fly in Bank 2 at 2250rpm to practice my collective management and not sacrifice my flight times. I found that 2250rpm gives me a long flight time and still gives me plenty of performance to fly lower headspeed 3D. If I want to really show off the 550X’s abilities I can crank her up to 2450 in Bank 3 for extreme fast forward flying and hard 3D.

All size batteries easily fit on the included slide out locking battery tray. If you only have one battery tray, swapping out flight packs is as easy as un-strapping the Velcro strap and attaching another pack. I keep 5 packs on trays ready to swap out between a busy day of flying or testing. I highly recommend buying a few extra battery trays and straps though. It makes swapping batteries between flights a breeze. Two battery trays cost $25 and the straps are another $4. I found the best places to purchase extra battery trays and Align parts are HeliDirect and LowerHeli. They ship the same day you order with 2-3 day priority mail and I have always received my parts promptly.


I still am a firm believer that a mid size heli with 550mm main blades is the best choice for a beginner to step up and advance into up to a “bigger size” helicopter. For $590 this helicopter kit comes as upgraded as it gets with a full metal head, metal tail and fiber carbon parts along with Align’s new MX motor. Overall the T-REX 550X is an extremely capable 3D helicopter for fun or training purposes with lower costs to repair if you were to put it in. It has very good power to weight ratio and also a light disc loading for a mid class model. This makes it very agile but also capable of handling a variety of different pack sizes. The increase in size from the T-REX 500L makes it much more stable and easy to see in flight.

For a midsized 3D machine, the T-REX 550X provides the stability of larger helicopters, while maintaining portability and economical operation of a smaller helicopter. The kit was well packaged, the manual was well thought out and easy to follow. For a smaller model it remains maneuverable even at lower headspeeds, yet is able to handle the hardest smack 3D you can throw at it. The kit is a great value considering all that is included. The T-REX 550X is everything I expected it would be. This helicopter can satisfy all the needs for a model in the midsize class. From the ability to fly smooth for 6 minutes or to fly hard and fast in the same model is a bonus. Minimal maintenance, amazing performance and a stunning appearance is certain to keep it at the top of its class for a long time!