3D Capable and SAFE! By Horizon Hobby
This article was originally published in RC Heli Pilot February/March 2016 issue.
Words By Dan Goldstein
Photos By Sarah Hayes
The Blade series of helicopters exemplify simplicity and user friendliness. Due to increasing popularity and technological advancements, Blade has integrated flybarless systems into several of their helicopter models. The 270 CFX sits between Blade’s 180 CFX and the 300 CFX. The 270 provides a more optioned out model compared to the smaller 180, steps up to 6S power, utilizes a pro-level bailout enabled flybarless gyro with the AR7210BX and gives a bit more presence to handle the rigors of flying outside. The 300 CFX is less costly, but is actually a bit smaller, particularly in the main rotor diameter and runs on 3S and doesn’t have the bailout capable AR7210BX gyro. I feel the 270 CFX is blending the portability of the micro/sub-450 size with true “pro” level capabilities of a 450+ sized model.
NEED TO KNOW
DISTRIBUTOR: Horizon Hobby
TYPE: Mini electric
FOR: Intermediate to advanced
• Fully 3D capable
• Simple setup
• Replacement parts and batterie are inexpensive
• Bail-out feature inspires confidence
• Most gyro setup and features locked out without paying for a software upgrade and cable
• No gyro manual included
The 270 CFX is a cool model in that it gives you the benefits of the sub-450 size in low parts and battery costs, but with full collective and tail authority that most micros and minis don’t afford. The 270 also isn’t so small that it falls victim to being totally lost in sight when flown at the field. It’s nice to see a fully optioned airframe, but when I learned of the locked gyro firmware I felt a bit frustrated. Given the capabilities of the airframe and that this model is really meant for the intermediate to advanced pilot, curtailing the customer’s ability to more finely tune the gyro really didn’t make sense to me. On the other hand, out of the box with some minor programming tweaks allowed with the ESC, the model is quite fun to fly.
WHAT’S IN THE BOX:
This model comes packaged in an attractive cardboard box that doubles as a carrying case. The model is nestled in Styrofoam and is easy to pull out for quick lunch break flights. You get the model, of course, and some basic tools. You need to purchase the flight batteries, charger and a DSMX compatible radio transmitter separately.
The instructions for setup are meant to be very simple. However, due to the inherent complexities of a collective pitch FBL model and that the target consumer should already have some flight experience, I advise going through a more traditional setup process to verify the factory got it right. I had a Castle Link adapter on hand so I could run through the ESC’s programming top to bottom as per Castle’s instructions. The end points for my radio did wind up slightly different from the manual’s suggested settings, but not enough to have caused an issue had the manual been followed explicitly. I did have to do some digging around on the internet to figure out the main gear tooth size, but I did get it figured out and set up the SetRPM governor function accurately. I also dropped the Initial Spool Up rate down, along with the Motor Start Power. I personally prefer a slower start up so I have a few more seconds to get focused on the model just before lift-off.
Once the ESC was bench ready, I bound the model to the radio with my sticks in their fail-safe positions. This saves the new end- points to the fail-safe mode. Once that was complete I moved to the FBL gyro. The AR7210BX included with this model is at its core a fantastic, easy to use gyro. I use the precursor (AR7200BX) on several of my models and love the simplistic setup and reliable performance. The unique feature of the 7210 is that it now incorporates a SAFE bail-out function. Technically, this gyro has five modes of bail-out operation, but here is where a rather unfortunate factor crops up. Blade locked out several of the setup selection features of this gyro. One in particular is the only SAFE mode available is “Bail Out Rescue Mode with Collective Pitch Control” and you cannot adjust Setup J for the 6 degree pitch learning. If you’re inclined to adjust the FBL settings and unlock all of the features, you’ll need to purchase the BeastX USB interface cable/adapter (SPMA3030), download the StudioX software and pay an additional $105 for the unlocked firmware.
After getting over the bit of frustration about not being able to go into the gyro setup to verify it’s all correct, I bound the model again to insure my fail-safes were all properly set since I had changed the ESC EPAs. Before it went back into the box, I verified that all the controls worked in their correct directions, the flybarless gyro was compensat- ing in the correct directions and the digital trims worked properly. Everything checked out perfect. I charged the battery at 2C and it took 20 minutes to fully charge. Internal resistance ranged from 8.8mOhms to 11.1mOhms. It was time to drive to the field and throw the 270 into the air and see what happened!
Spektrum DX9, SPMR9900
E-flite 6S 910mAh 30C LiPo, EFLB9106S30
Do not fly the model without going through the ESC settings and checking to make sure they are correct. You can get a Castle Link Adapter from Castle Creations and the Castle Link software is free for download from http://www.castlecreations.com
Unfortunately, Blade didn’t include a manual for the AR7210BX, so be sure to download it from Spektrum’s website
When you’re ready to fly, turn on your transmitter, make sure the throttle is at full low and wait 5 seconds. Then, with the flight battery NOT installed in the model yet, carefully plug in the battery to the model’s battery connector. Wait for the model to bind and the servos to center. This will take about 12-15 seconds since the AR7210BX displays the bailout function setting for 8 seconds on start-up and then goes into the regular initialization. Next, install the battery into the model’s airframe. Check your controls to make sure the swash is tilting in the correct direction with your stick inputs. You can also check to make sure the flybarless gyro is compensating correctly by tilting the model and confirming that the swash- plate tilts in the opposite direction. This modified procedure allows the model’s gyro system to initialize without induced vibration from plugging in the battery. If the gyros initialize while the model is being handled it could cause an annoying drift and is even more critical to the bail- out alignment.
Lift the model into a hover quickly! One side effect of the flybarless system is that it is highly sensitive to ground resonance. The flybarless gyros can adversely react to vibration while spooling up on the ground and this can cause the model to tip over. To avoid this phenomena, raise the throttle and quickly lift the model up off the ground. When you go to land, get the skids on the ground and then quickly lower the throttle.
Buy more flight batteries! Fortunately, at a 2C charge rate, the battery only takes about 20 minutes to charge. You can charge at up to 3C with the E-flite 6S 910mAh 30C LiPo.
Check and adjust the tail belt tension. Loosen the two tail boom clamp screws in the rear of the main frame. Then, with the battery installed, but not plugged in, hold the model by the tail case. Let the weight of the model set the tail belt tension. Make sure the tail output shaft is perpendicular to the main shaft and then tighten the tail boom clamp screws. If you live where you experience seasonal temperature change, you will need to check and adjust the belt on a per season basis. It will expand and contract with a change in temperature so it’s best to set the belt tension outside at the temperature you anticipate flying the model in. Once set, you should be good for the season.
Get a good balancing charger like my Revolectrix Power Lab 8, the Power Lab 6 or comparable unit.
Use Dry Fluids Gear Lube on all gearing and Heli Lube on all shafts and bearings except the one-way bearing. For the one-way, when and if you have to lube it, use automotive grade Dexron transmission fluid.
IN THE AIR
Normal Flight: Hovering this model is pretty much as stable as a typical 450-size model. Fortunately, on the day I was testing it was dead calm. Given the collective authority, I suspect this model could well handle a little bit of wind without it killing the fun. The recommended dual rates and expo settings aided in taming the model’s sensitivity to inputs and provided a nice, smooth feeling in flight.
Forward: In the second Idle Up and the head speed cranking at 3500, the 270 goes quickly and is out of sight fast! Tracking was quite good, though I wasn’t contending with any wind. Nonetheless, forward flight gave way to mild bouts of drag racing up and the down the flight line.
Backward: With the quality gyro on board, a fast tail servo and carbon tail blades, back- wards flight was stable and controlled. I didn’t experience any tail blowout or odd tracking while backing it up.
Aerobatic: Loops, rolls, flips, no problem. The 270 CFX is as capable as its bigger brother, the 450 X. The model didn’t exhibit any bad tendencies during aerobatics, and the AR7210BX’s certainly lends its gyroscopic power to refining the ability of this small model.
Auto: This model is capable of auto despite not having an auto-hub. The autos were okay, but since the motor also free turns when in Throttle Hold, the inertia bleeds off quite quickly. The best bet is to aim for a soft surface or tall grass in an emergency. Otherwise, low altitude autos were manageable, but not nearly as acrobatically capable as a 450+ size model with a one-way bearing equipped hub.
3D: The 270 CFX was made for 3D!
Hurricanes, piro-flips and tic-tocs all flew well and briskly. The model truly excels as 3D practice machine. The bailout function affords you a way out should you lose orientation and it does work well. I found that I pushed myself harder knowing that I had some measure of saving it by a switch if my brain glitched. Fear is one of the biggest inhibitors of progress with RC helis and the AR7210BX’s bailout feature drastically reduced the fear factor.
FLYING WEIGHT: 22.08 oz. (626g)
LENGTH: 22.04 in. (560mm)
HEIGHT: 7.48 in. (190mm)
WIDTH: 4.52 in. (115mm)
ROTOR SPAN: 24.21 in. (615mm)
ROTOR DISK AREA: 460.5261 sq. in.
ROTOR DISK LOADING: 6.90 oz./sq. ft.
TAIL ROTOR DIAMETER:6.37 in. (162mm)
CYCLIC SERVOS: Spektrum Digital High Speed Servos H3050
TAIL SERVO:Spektrum Digital High Speed H3060
GYRO: Spectrum AR7210BX Flybarless System
ESC: Castle Creations Talon 35
MOTOR: Blade BLH4828 2350Kv 6-pole Outrunner
MAIN ROTOR RPM AT HOVER: 3500
DURATION: 4 minutes
MINIMAL FLYING AREA: Gymnasium or small field
COMPONENTS NEEDED TO COMPLETE:
Requires a multifunction 6+ channel transmitter with Spektrum DSMX 2.4GHz technology and a 6S flight pack with at least 900mAh of runtime at 30C.
Material: Carbon Fiber
Type: Stacked Plate
Servo linkage type: Direct CCPM
Grips: CNC Aluminum
Head block: CNC Aluminum Links: Plastic
Swashplate: CNC Aluminum Control: CCPM 120 degree
Drive system: Belt
Auto Capable: Yes
Tail Pitch Slider Type: Dual pin control Tail Blade Grips: Plastic
Tail Case: Plastic
Boom Material: Aluminum
Boom strut material: NA
Rotor to pinion: 12.2728:1
The 270 CFX holds an interesting place in the Blade Advanced Series line-up. It’s a model that has a similar presence and flight performance to the ole’ reliable 450, gives comparable flight times and is fully optioned out of the box except for the locked out gyro firmware unless you pay more money. It’s quite a nice package and the stock setup doesn’t leave much on the table performance- wise. The support from Horizon and their dealers is excellent, so should you crash (though you hopefully won’t because you’ll be using the fabulous SAFE bailout), parts are widely available. Some of the parts are shared with the 300 CFX, 360 CFX and 450X too. I certainly would have appreciated some documentation, a note, something in the box indicating that I’d have to pay more to unlock the AR7210BX firmware to its full version. The majority of pilots who would fly this model, probably would prefer to be able to get into the programming and tinker.
I think this model would be great for a pilot who is looking for something other than another 450-size or hasn’t had a 450, but wants the portability, power and capabilities of a collective pitch machine. I really enjoyed the 270 CFX and it felt comparable to a 450- size model’s capabilities. Certainly, in my opinion the standout feature is the SAFE bail- out. While there are a handful of competitors out there in this size, Blade’s incorporation of the amazing, albeit held-back AR7210BX, really makes it a perfect out of the box practice machine. The SAFE bailout worked so well it got me thinking about retrofitting all my other models to use it!