The electric ducted fan and examples of RC jet models that are available. Hints and tips on selection and the ability to buy some of the latest types.
The photo below shows a typical, modern EDF unit, the Great Planes Hyperflow 56mm. The main components are injection molded plastic.
Depending on the motor used, The efflux speed of this unit can be up to 165MPH!- with a thrust of 28.9 oz.
For further information on the Great Planes Hyperflow 370 EP Ducted Fan w/o Motor GPMG3910 , please click here.
The recent improvements in electric motor and Li-Po battery technology have enabled the development of electric ducted fans to reach fantastic levels of performance. The secret is in the RPMs available. Now revs can be close to 50.000RPM. This results in high thrust to weight ratios, that in turn gives true jet-like performance.
This chart shows how thrust increases as RPM increases.
To ensure that all the thrust developed is used to fly the model, the intake and efflux areas must be large and the duct must be smooth.
The critical area is the swept area of the fan blades. For the Hyperflow unit the Fan Swept Area (FSA) equals 2.74 square inches.(17.68 square cm) If a straight intake tube were to be used, then the entry area would be 134%FSA. The exit or efflux area should be between 90 and 99%FSA. So if you are designing your own EDF jet, or trying to improve the performance of a purchased jet, then measure these dimensions as accurately as you can and check the ratios.
More information can be found in the Hyperflow manual-click here to view it.
When selecting a ducted fan jet model, I look at the all-up weight, of the finished model and ensure that the total thrust of the fan(s) is close to, or even exceeds, this figure. Also consider the wing area. A small wing will mean a high wing loading, The larger wing area translates into a better handling model that flies better at low speeds. This last attribute is particularly important during landing!
The Great Planes Hyperflow EDF is IN STOCK
This is the EDF unit used in the E-Flite F-4 Phantom 32 DF ARF and the E-Flite Habu 32 DF ARF.
Construction is from injection molded, high strength fiberglass filled Polyphenylene. The 5-blade rotor is factory balanced and comes with an aluminum spinner.
The center body fairing is designed to minimize drag.
Assembly of the unit is required but this should be a simple exercise.
E-Flite Delta-V (R) 32 80mm EDF is in stock.
This is the motor designed for use with the 80 mm ducted fan unit described above.
The motor is of 6-pole design and includes mounting hardware. It is rated for 1.400 continuous input Watts or 1,665 maximum burst.
The design also features ball bearings and a hardened steel shaft that should result in minimum friction and long life.
This web site has everything for the jet flyer! Whether your interests are EDFs or Glow engine powered Ducted Fans or turbines. There is valuable information here. EDFs are offered from the smallest to the largest.
The E-TURBAX electric ducted fan unit is 5 1/4 inches(133.3mm) outside diameter, with a 4 3/4 inch(120mm) diameter fan. Thrust can be 13-15 lbs, with an RPM of 30,000. This is certainly one of the largest units available.
Jet Hanger Hobbies have been involved in the design and flying of jets for a long time. Visit their site, by clicking here.