Fan Units

Click on:

EVF System Pricing

For information and pricing

The BVM EVF instructions include additional information about Li-po batteries, proper use of the Thunder Power 1010 charger, and other useful information for anyone interested in electric powered jet models. Click here to download the instructions.

August Air Testing

We have had multiple opportunities lately to evaluate the Electric VioFan operation in rather challenging conditions.
A few outings at our Florida field, the Liberty Bell event in Pennsylvania, three days in Maryland, and twice again just recently in Florida were optimum opportunities. Ambient temperatures ranged from 97° in Florida, to 95° in Pennsylvania to a record breaking day of 102° in the Maryland area.

The intense heat and humidity proved more challenging to the human body than to the EVF system. While there is a slight deterioration in fan efficiency compared to a 70°-80° day, there were no issues with the motor or ESC operation.
Since the LiPo batteries are already at 90° or so prior to flight, we found it prudent to deduct 30 seconds from our usual flight time using the 5,000mah cells.
We have discussed flight profiles before and know it takes 10-20 flights to develop a strategy that minimizes the energy consumption. So, with this experience in our pocket, we constantly logged 5 minute flights on the 10S system and 5:30-6 minutes on the 12S system and did not exceed the target 80% battery consumption rule.

Field Charging
always in the shade

The Electra Jet with EVF power and a Spektrum radio for guidance are a great combination.

click to read more about Spektrum radio systems

The Electra Jet's (with EVF propulsion) introduction at Florida Jets '07 was impressive. So much so that many of our dyed-in-the-wool turbine customers want to add one to their arsenal of sport jets.

The utter simplicity, quiet operation, model field acceptability, easy transport, and the fact that it flies like its big brother "Bandit" are convincing qualities.

Impressive Performance

It's not a Viper or a Bandit but just the right in between size to absorb the 5+ H.P. we now have available for the EVF. We have learned a few things over the years and the inlet design reflects our experience in that area. The fan, inlet and tailpipe designs must have a determined performance point prior to executing the tooling. We believe that the design point we chose provides an excellent balance between take-off thrust and thrust available at 150mph. Enthusiasts at Florida Jets '07 or other recent flight demo's can attest to the wide envelope of performance of the Electra / EVF combination.
One really has to see it to fully appreciate it, but this video should help.

BVM's tooling processes allow us to produce the EVF with precision and in moderate quantities.

We believe that the flight performance, durability and quality of manufacture of the EVF is unmatched in the industry. In-the-field use will confirm this.

NOTE: The 25C 5,000mah 5S1P Saddle Cells™ from either Thunder Power or FlightPower are identical in cell format and capacity. BVM supports both manufacturers of these excellent Lipo batteries.

Power Usage & Charging

An energy efficient flight routine allows reliable 5 minute flights on the 10S system and 6 minute flights with the 12S system. Start the flight timer at the beginning of the take-off roll and allow 1 min for the landing pattern described below. The total flight time is noted at the end of the landing roll out.
Use full power for high speed fly-by's and zoom climbs. At the top of the climb, shut off the motor, glide down to a comfortable altitude, then use 1/2 throttle to cruise into position for the next maneuver.

Half throttle will produce about 7.5lbs of thrust and consume 36 amps (10S) or 28amps (12S) and about 90mph. Save enough battery energy for a high speed entry into the overhead "Pitch Out" (USAF) or "Break" (NAVY), chop the throttle and zoom into a landing pattern. Program the flaps and gear such that you cross the "Numbers" (approach end of the runway) needing just a little power to land.
It might take a dozen or so flights to get totally familiar with the proper throttle management.
The heli pilots that stay with the 80% rule are getting hundreds of cycles from these 5000mah cells.
For field charging, we set the charger at 5amps (1C) and are able to restore the 3800-4000mah in about 40 minutes. For in-the-shop charging we charge at .8C or 4 amps.
Remember, the batteries must cool down close to ambient temperature before they can be safely charged. The BVM Cool Trays™ greatly reduce the cool down time.

Click here

EVF System Order Form

Click on:

EVF System Pricing

For information and pricing