PLANE: BVM Electra Jet MANUFACTURER: Bob Violett Models DISTRIBUTOR: Bob Violett Models TYPE: Sport Jet FOR: Intermediate to experienced WINGSPAN: 60 in. WING AREA: 710 Sq. in. WEIGHT: 14 Lbs. 8 ounces WING LOADING: 47 oz./sq. ft. LENGTH: 67 in. RADIO: 6 - 7 channels required; flown with a JR DX7 transmitter on 2.4GHz, AR7000 receiver, (10) servos: (2) JR 3421s, ailerons; JR 3421, rudder; JR DS821, steering; (2) Futaba 9252s, elevators; (2) Futaba 9252s, flaps; JR 791 Retracts. Flight Power 2S2P 2-cell 3,000mAh LiPo with Duralite Regulator, JR Deluxe switch.
POWER SYSTEM: Electric Vio-Fan (EVF) with BVM-modified Neu brushless inrunner motor; Castle Creations PHX 110 HV speed controller; two batteriy brands were test flown: Thunder Power 651P and Flight Power EVO 5,000, both configured as BVM spec Saddle Cells™
FULL THROTTLE POWER: 13-14 Lbs of thrust ; 103 amps, 4,000 watts; 17.2 W/oz., 275 W/lb. FULL THROTLE POWER: 13-14 Lbs of thrust ; 103 amps, 4,000 watts; 17.2 W/oz., 275 W/lb. TOP RPM: 26,000-27,000 DURATION: up to 6 minutes depending on battery pack size, conditioning and throttle management MINIMAL FLYING AREA: Large flying field PRICE: $1,495 (airframe); $1,195 (10S EVF power system) COMPONENTS NEEDED TO COMPLETE: Viojett EVF fan unit propulsion system, Saddle CellM
Spellbinding, high performance electric ducted fan!
by Frank Tiano
I'm guessing that I started flying jet models in the early 80s. Back then, there wasn't much choice in selection of available models, but the few available had a couple of things in common. One, they were from the same manufacturer, and two, they worked! The first successful (with a capital "S") models were from Bob Violett Models in Winter Springs, Florida.
I remember them well, a Sport Shark and an F-86, two models that performed well, had lots of pizzazz sitting in the pits and were a ball to fly. Here it is almost 25 years later and I have gone the complete circle, returning to a ducted fan airplane, after spending many years, a small fortune and countless hours building and flying turbine powered jets.
The Electra jet is truly an amazing machine, not only because of its engineering excellence, but because it has come along at exactly the most perfect time in my, and hundreds of other's, modeling careers. It is no secret that sites that can, or will, accommodate noisy, turbine powered models are becoming rarer every day. Add that to a scenario where older modelers "want" a jet but may be concerned about their ability to handle one, in terms of both cost and performance, and you may already be getting a whiff of where I am going with this.
John Banner brings the Electra in for his first landing. The airplane settles in nicely, has no tendency to wobble from side to side and is controllable even in a light crosswind. Flap adds lift and induces drag, which is great for small field operations.
Here we have John Banner in the foreground, followed by the Two Bobbys, Bob Violett and Bob Fiorenze, sort of the James Spader and William Shatner of the Jet world. Notice how the different schemes brought a different personality to each Electra?
Those who have previously read my reviews might remember my style. For those reading one for the first time, I'll be brief. A review should tell you the good things about the product, as well as the bad, and prepare you for any nuances to help you in deciding if this model might be something to consider in your purchasing future. That's what I do. So if you're looking for an instruction manual, go on line and download something from the BVM site. If you want the real skinny, go grab a Pepsi, Club Soda or a Coffee and keep reading.
The Electra is a pretty cool name. I have actually had experiences with 4 different Electra's in the past. One was in 1976, when my favo ride was an enormous, black, 455 cubic inch, Buick Electra Limited 225 coupe that consumed so much gas, that if you left it running at the gas station while filling it up, it might get ahead of the pump! And second, was a ride in a Lockheed Electra, a fabulous turboprop airliner, third, a movie titled Electra, starring that really, really hot Jennifer somebody chick that used to star on TV's Alias, and fourth, probably my all time favorite Electra, Carmen Electra!
The Electra looks like it's going 200 mph while standing still in front of builder John Banner! A very respected modeler in our area, John took his time to make an excellent model, one that was admired by all pilots at the first jet event he brought it to, the Florida Jet Rally. While the Electra looks like a high performance ship, it is very docile, easy to manage and an absolute ball to fly.
U.S. MANUFACTURED!
This is primarily a sport model with a flight envelope larger than it needs. It's just the right size to fit in some large vehicles and almost all small trailers, in one piece, even though it's a 3-piece airplane. With the wings on, it spans 60 inches, packs in 710 square inches of wing area and can weigh between 13.5 and 15 pounds ready to fly. This bird is manufactured in its entirety right here in the USA.
All necessary parts to build the thing are included, except of course, the radio gear, propulsion system and 'fuel," I mean batteries! If you buy one, you will probably do like John and I did the first time you open the box, meaning, you may be so overwhelmed with joy, that you might have an accident! This kit is extremely well crafted!
Oh, by the way, when I mention John I am speaking of John Banner, my shipping and warehouse manager who happens to be a model airplane enthusiast like I am. Talk about job security! Anyway, I made John a deal. If he would do most of the building, and finish the Electra, I'd consider giving it to him as a birthday present after it was finished (he recently lost his best flying airplane). So, with me looking over his shoulders, we examined this magnificent kit and made some notes, which I'd like to share with you now.
THE KIT
First, all the fiberglass components are very well done, extremely light and very strong.
The simple but rugged Electra gear features metal and carbon fiber materials with heavy duty, extremely durable, wire struts. Notice that ordinary DuBro or Sullivan tires work well.
Second, all wood parts, like in, "did I forget to mention that you actually build this model," parts, are laser cut and labeled for easy identification. Third is that the accessory package has been well thought out.
It contains an awful lot of carbon fiber parts, cool looking ones actually, and was also labeled to indicate what the parts were and where they would be used. So, in general, this kit is not only complete, but all components are of very high quality.
It is also important to know that the Electra comes with a fully illustrated, 65-page instruction manual packed with diagrams. Now, I gotta tell you, this manual thing is very, very important for several reasons. It not only takes the builder step by step, it also gives hints on what adhesives to use, where extra time needs to be spent for parts alignment, what radio gear fits best, the length extension cables and a host of other helpful hints. The last page of the manual calls for specific JR servos that not accidentally fit the laser cut servo trays. If another brand of radio is being used, simply cross reference the servo for size and power and you'll be fine.
This gives a great overview of the parts used in construction of the wings and stab of the Electra. The black parts are made from carbon fiber and all other parts are either balsa or plywood and all are laser cut.
FUEL
You might consider the batteries used to power your jet as "fuel", I know we do. One major difference however is that your model weighs the same after using the fuel as it does at takeoff. And the cost of this "fuel" may at first seem prohibitive, but you have to look at it as if you're purchasing a year's worth or more in advance. The associated gizmos that allow the fuel to "work" might be considered the oil and spark plugs. When we look for batteries with enough horsepower to propel a 14 pound jet to speeds of over 150 mph, we quickly discover that there are not many choices.
For batteries of this power and relatively compact size I recommend two major suppliers: Thunder Power 651P and Flight Power EVO 5,000 Saddle Cells. These Saddle Cells are specifically configured for the BVM Electra. We obtained samples from both companies and found them both to be very efficient in getting the job done. The differences between the packs were truly miniscule! The Thunder Power packs have a 5000mAh capacity and the Flight Power packs 4900mAh.
Both require a great charger. The Thunder Power 1010C recommended by BVM worked flawlessly for both packs, along with the Thunder Power TP-210V battery balancer. The PHX 110 HV Castle Creations ESC is already programmed and installed by BVM in the Viofan ducted fan power package.
Fuel Mileage? After testing both battery packs we concluded that they both are similar in performance and longevity. With the Thunder Power 5000 packs installed, we flew a "cruise" flight, only going to full throttle briefly, a couple of times, for approximately 4.5 minutes. We landed and checked the packs. Of the 5000mAh capacity, we used just 2480 and it took 38 minutes to fully recharge at a 1C rate.
An almost identical pattern was flown with the Flight Power packs, perhaps staying at full power a bit longer, and we used 2612 of the 4900 mAhs and it took 40 minutes for the recharge. We can not determine if one brand of battery is any better than the other, both performed flawlessly. And service from both companies was incredible.
Charging Saddle Cells
Our Thunder Power 1010C charger came with something called 2.0 Firmware installed, which allows up to a 10s LiPo to be safely, charged, balanced, and discharged. After speaking with Mark at Thunder Power we upgraded the charger to the version 2.3 Firmware(downloadable from www.thunderpowerrc.com) which adds some more cool features to the 1010c Charger. The 2.3 Upgrade allows us to charge and discharge LiPo, NiCd, NiMH as well as a A123 lithium ion batteries. We also used the TP-220 balancer, which, when used in conjunction with the supplied data cable, "talks "to the charger every 10 sec and constantly displays individual cell voltage. Should a cell imbalance become to great, the charger will automatically reduce the rate of charge or stop charging. You can view the data that is being sent to the charger, and the imbalance. I never saw our packs get over a .035 imbalance.
The only problem I have found with this charger is it is very picky about the input voltage. Even if you set the cutoff input voltage to 11.00v it still wants to "fault out" below 12.70 which is usually a fully charged PB or lead acid battery. Here at the shop we had good results with the 25amp power supply that you can pick up at radio shack, but if you want to run multiple chargers off of the same power supply you will need to purchase an Iota dls-55, a 55 amp power supply that will allow you to run two thunder power 1010c's, one at full power and one running at half. But get ready to open your wallet for this one, as they are not the cheapest power supply on the market! But if you have the need to run multiple chargers, all at the same time, it is the way to go. Over all this is one great charger and a tool that any electric flier should have in the old flight box. For sure, with the available 2.3 firmware update, this may be the only charger you need.
CONSTRUCTION
Many of us older modelers have seen just about any
type of model construction you might imagine. I mean,
I started when you had to cut every part to size, sand it to fit and use some glue that took, like, "for never" to cure! John's first reaction to the built-up wing was "What's this?" But after studying the full size plan and reading through the instruction manual, he concluded that while it may appear different at first, the wing features fairly typical construction, only with better fitting parts than is typically seen.
The wing is built upside down, in a provided jig, and goes together perfectly. The directions are very clear and call for specific formulas of Zap glue in specific areas of construction.
Here's a finished wing panel with the landing gear being screwed to its "flex-plate", a special, replaceable, carbon fiber plate that helps to absorb and minimize transferring shock effect to the internal structure.
You wanna talk "neat"? This is the laser cut nose gear mount, complete with "flex-arms" and the dual servo mount. The servo on the right is a JR 791 Retract Servo while the JR DS821 digital handles steering chores.
The wing utilizes a laser cut building cradle. All parts line up exactly as they should and three formulas of Zap are used at different points for adhesion. BTW, the wing is so good looking in the pre-sheeting stage that it's almost a sin to cover it up. John must have proudly shown a dozen people his handiwork before Zapping that top sheeting in place! While normal modeling practices are used for most of the Electra's construction, there are a few places where you may run across a procedure you are unfamiliar with. In these cases, simply wrap the parts in bubble pack and send it to me and I will do it for you. JUST KIDDING!
Nah, if you were to come across anything unusual I promise you that between the plans and manual it will be clear as crystal in a jiff. And best of all, BVM has a great web site, one that addresses any changes in any of their kit instructions, on an almost daily basis, and, they certainly would not mind a phone call to help you out if you get flummoxed. We had kit number three, meaning that some procedures needed tweaking, and the BVM crew were courteous and helpful.
CUSTOM PARTS
Every part of the Electra is custom built for its purpose. For example, the landing gear was designed as sport jet gear from the ground up. BVM's gear uses top quality American made, aircraft grade, high performance materials. The same goes for the ducted fan system, which has actually been wind tunnel tested!
EASY MAINTENANCE
The aircraft itself incorporates several features to make maintenance as easy as possible. For instance, the canopy and motor compartments are both accessible by activating just a single hatch latch. Once the hatch latch is depressed, the canopy portion slides forward and the rear hatch becomes removable for accessing electronic components as well as the nose gear steering and retract servos. Yup, I did say retract servos. Like in no air system here. No leaks, no runs, no errors!
The main hatch, called the Power Hatch, exposes the fancy battery packs, called "Saddle Cells" the fan itself and the hot looking clear tailpipe. A large nose gear door provides ready access by even the most cumbersome, clumsy fingers. You can easily reach nose gear flex arms and retract gear.
A hot fly-by at 160 mph, steady as a bulldozer on blacktop. At 160 mph, the airplane is traveling at
234.96 feet per second, so in 5 seconds it is a little over one fifth of a mile away. Cruising speeds
of a hundred or so are more fun, easier on the heart rate and offer more time to ogle the model!
A well thought out bottom hatch covers the wing mounts, main gear servo and linkages and the elevator servos. The landing gear uses toughened 3/16 inch diameter, coiled, struts for light weight and durability. Since this bird is not turbine powered, "you don't need no schtinking brakes" so the supplied Dubro tires and wheels are used effectively. Oh yeah, and speaking of turbines, or lack thereof, remember that you and your Electra will be welcome at any flying field and you won't need a waiver to fly it either!
FINISHING
The one last thing that must be done, that some may be unfamiliar with, is that the model must be finished. The wood components may be covered in plastic or mylar film or fiberglassed and then painted with your favorite method. The glass parts have a fabulous coat of white paint already applied already so it is really ready for trim paint. Some modelers have used quality spray cans, and actually produced a decent looking bird. However, we chose the automotive paint PPG for all aspects of finishing, from primer to clear coat. John picked out some outrageous colors that really complimented each other!
Since the modeler finishes the Electra in the colors of choice, all sorts of effects are possible. This is Bob Fiorenze's Electra painted in Navy scheme. Notice that partial flap has been dialed in for high performance, short takeoffs. These colors are extremely bright and easy to see on a sunny day.
The markings were supplied by Pro-Mark and what a bonus they turned out to be. They simply "rub off" with a little pressure from a balsa stick and they add so much color, contrast and realism to the model, it is unbelievable! We had several sheets of stock jet material to choose from, everything from hatches to insignias. They even do custom jobs, should you need some special characters, caricatures, or nomenclature, like nose art or buzz numbers for a World War two model. Try Pro-Mark for your next project, you'll find the product easy to work with as well as a dynamic addition to your model.
JR DX7 2.4GHz Radio using Spektrum DSM Technology
There is only one radio you ought to be using in the Electra if you want to absolutely guarantee success. BVM calls for the JR DX7 on 2.4GHz, a 7-channel radio, at this time and all examples of Electras currently flying are using this setup. The radio has great features and can be programmed properly with a minimum of fuss. In other words, you've got 7 channels and you can absolutely live with it! John did use two channels for flaps, using Aux 1 and 2 for easier setup. We used a heavy duty JR Deluxe switch for the radio and under no circumstances should you use anything but heavy duty servo extension cables, the ones with gold connectors.
BVM recommends JR servos and guarantees they will fit in the in the allotted spaces. When it comes time to choose retract servos, keep in mind that the JR puts out about 250 ounces of torque.
FLIGHT PERFORMANCE
Well, we had to postpone the first flight of the Electra for a day and a half due to severe crosswinds at the site we were scheduled to fly from. However, BVM graciously loaned us one of their pilots, Dustin Buescher, for guidance during the maiden flight. In fact, to be totally honest, John and I thought it was a pretty smart idea to have Dustin make the first flight, just to check everything out. Turns out, all was perfect, no kidding, not even one click of trim was necessary for adjustments. Subsequent flights were easily performed by both John and myself and we concur, other than the lack of noise and the smell of burnt Kero, flying the Electra is as much fun as flying any turbine powered model with far less concern for the environment. I had already flown the electric powered BVM F-86 months earlier, at Top Gun, in fact, and found the Electra to be as good in every way, only quite faster when at full throttle. This airplane does everything well, it is fully aerobatic, meaning, it will do any maneuver that any other jet powered aircraft will do, other than something with variable thrust and a directional exhaust nozzle.
It is as honest as the day is long, maybe even more honest, and it has absolutely not one bad trait. Not one! To take off, you just point it down the runway, hold in some up elevator and it just flies off when it has reached the proper speed. You may perform a steady climb-out, turning away and notice that the speed is increasing at a faster rate than you would have expected. After a couple of laps around the circuit John did some slow flying with flaps fully extended. It is amazing how slow this bird will fly and still maintain full directional control. I have no scientific data but I am guessing the top speed at around 180 and slow flight speed somewhere around 30 mph. Mr. Violett's personal machine has been clocked at a constant 28 mph and as high as 193, depending on the specifications of the Saddle Cells.
John was tickled about one particular maneuver, the plain old roll. He input about 1/3 aileron stick and the Electra just rolled about its axis, as though it were guided by a fine wire that had been threaded down the nose and out the tailpipe. To travel from slow to full speed takes only a few seconds, maybe 6 or 7, and the Electra will execute a 400 foot diameter loop, from level flight, with little effort. As I said, this bird can do it all.
It is especially enjoyable to watch it fly a figure eight pattern, with partial flap and an average speed of 50 mph, at about 15 feet altitude. It's also pretty comforting to know there is little, or zero, chance of a power failure while doing these low and slow maneuvers!! The model is so stable that I highly recommend it to anyone who can fly pattern and keep it visible through large maneuvers. If you get a chance to go to a jet rally and a BVM rep is flying one of these machines, go ahead and ask for a turn on the buddy box. They will gladly accommodate you and you will be in for a real treat.
ELECTRIC VIO-FAN
The heart of the power system is the Electric Vio-Fan (EVF) unit. Since the physics of air flow has not changed in the past who knows when, the original Viojett ducted fan design could be retained. Back in the days of glow powered fans, the Viojett was unquestionably the most powerful ducted fan unit available for models, and its 7-blade design was comfortably adaptable to electric power with little fuss. The fan is manufactured a bit differently in 2007 than previously, incorporating an even stronger carbon fiber thermo-engineering plastic. The BVM modified Neu electric motor and the Castle Creations Electronic Speed Control ( ESC) are cleverly integrated into the center body for very efficient cooling while offering quite a compact unit. In typical BVM fashion, the power system is delivered to us, the customer, completely assembled, balanced and test run. It is dirt simple to install and use, and it's simplicity of operation will appeal to, and perhaps amaze, any modeler fortunate enough to own one.
These battery packs are as compact as can be, and they are available with higher cell counts for even more power. The Charger and balancer are a must and can be seen on Thunder Power or Flight Power's web sites in full living color along with a complete manual you may download if you like. By the way, notice that Johnny Boy received an award for Best Craftsmanship for this Electra at the first event he entered!
While the Electra may be flown on 72MHz, RF noise filters and special arrangements for receiver location and an external antenna are required. The JR DX7 2.4GHz radio, available at most hobby shops through Horizon Hobby Distributors, is the radio recommended by BVM for piece of mind and trouble free performance. To date, several Electras have logged hundreds of flights, noise free flights, trouble free flights and interference free flights with the DX7 running 2.4GHz.
OPTIONS
Oh yes, while we're talking about the overall finish of the Electra, now might be a good time to tell you that since we first received our kit, there have been three optional, easy to build and install doodads released. NACA ducts not only look cool, they allow fresh air to enter and exit the battery compartment, helping to keep the packs cool as they discharge. Also available are a set of main gear doors that extend further down the strut for a nicer appearance (but useless if you're flying from grass) and a really hot looking set of under-wing missiles and their pylons.
CONCLUSION
The Electra is a complete, well thought out, easy to put together and overall a very attractive aircraft. Since its inception, battery prices have stabilized as performance has gone up, making this an ideal first time jet for anyone who has been itching to join this segment of model building. You can see the online side bars at www.flyrc.com for our impressions on the flight performance as well as some helpful thoughts on battery power, chargers and additional info. In a nutshell, we don't think that anyone interested in an alternative to a turbine powered, or glow powered, jet, would be one tiny bit disappointed with this electric powered beauty.
One last bit of information for you. Flying this all electric jet has some perks you may not first think of. For example, there is no fuel to drag to the field, no air pump, no fire extinguisher, no glow plug battery and no clean up stuff either! If that doesn't convince you how marvelous of an airplane this Electra is, you may prefer to go back to the simulator!!
