Easy-Jet - by Chris Martindale

27 Jul 09 - Repairs completed.

N of launches / Time 19 1 hour 48 mins
Wingspan 40.0 " 1.005 m
Wing Area 274 in 17.7 dm
Flying Weight 3 lb.5 oz. 1.53 kg 3 lb. 3 oz. 1.47 kg
Wing Loading 28.3 oz. / ft 86.3 g/dm 27.2 oz.  / ft 83.1 g/dm
Wing Cube Loading 20.5 - Racer (it better be fast!) 19.7 - Racer (better and more power
Motor 2 x Multiplex 450 Turbo 2 x Feigao 380-17S brushless 2409 Kv
Propeller 2 x Graupner Speed 6" x 5" 2 x Graupner CAM 5.5" x 4.3"
Batteries 8 Sub-C cells Sanyo RC-2000, RC-2400 or RC-3000HV 3S FlightPower EVO20 3700mAh or similar
Speed Controller Gordon Tarling Micro-Star 40 - 6 to 30 cells, 40A 2 x TowerPro W30A - 2 to 4 LiPo, 30A
Receiver / Battery GWS GWRD-8 - 8 channel - PPM - Dual Conversion - 35MHz with 4 cell 270 mAh pack.
Servos Ailerons - 2 x Volz Wing-Maxx
Elevator - 2 x Hitec HS-81MG
Rudder - Hitec HS-81MG
Static motor parameters  8 RC-3000HV give 37A @ 8.25V (305W) at 13350 RPM, which is 90W/lb (input).  This is overloading these cells a little, but the voltage is good so it should be OK.

8 RC-2400 give 35A @ 7.95V (278W) at 12825 RPM = 83W/lb (input)

3S FlightPower EVO20 3700mAh pack gave 46.6A @ 10.28V (479W) and 20400 rpm.   This equates to an input power of 148W/lb.
Flight performance Flies extremely well with plenty of power. Aerobatics are no problem and the normal flight duration will be around 5 to 6 minutes. I still need to play around with different propellers to find the best match. AWESOME.  It will now sustain a vertical climb, is really fast and loops can be as big as you like.

7 Sep 07 - I measured the maximum speed achieved during 2 flights - 106.2 mph (~171 km/h)

26 Jul 09 - After the model laying about since April 08 I finally got around to repairing it.  It didn't actually take long, it was just working up the enthusiasm to sort out the nacelles.

13 Apr 09 - Following a display at the Bath & West Showground I made a very heavy landing damaging the nose and nacelles, which will have to be repaired.

7 Sep 07 - I fitted the HowFast unit to the Easy-Jet as I know it is fast, but wanted to know just how fast.  The unit is designed to be independent of the receiver as there are no spare connections and removable when not in use.  Three installation photographs are shown above, giving the general layout.  It is fitted to front and underside of the hatch with the pitot and static tubes being fed through plastic tubing inset in the hatch.  The tubes are held in place by tape but this was removed here to facilitate the photographs.

27 Aug 07 - I had snapped one side of the stabiliser off landing in slightly longer grass, which I've only just gotten around to repairing.  I replaced the whole stabiliser and inserted two 1 mm thick carbon spars to reinforce the joint at the fuselage. I have also converted it to brushless motors and a LiPo pack.  An 8 minutes flight only used around 1.7Ah so plenty of capacity in reserve.

27 Jun 05 - Due to hangar damage the model sat around for a long time.  I've just completed the repairs and completed the static motor runs.  I replaced the original chopped down 7" x 4" APC-E propellers (reduced to 6" diameter) with Graupner Speed 6" x 5.5" propellers which should suit the model better.  Due to the increased pitch of the propellers the model should be faster but launching more difficult.  I will now launch this model using the bungee rather than hand-launch.

22 Aug 02 - The first flight was completed today, after a few initial problems launching the model.  The model flew very well, although I had far to much elevator movement.  After a couple of flights I turned on the tailerons, which noticeably increased the roll rate, and I leave them on now.  I still need to reduce the elevator movement a little further and try different propeller types and CofG positions.

30 Jun 02 - I've now finished the model and hope to get test flights in this week to allow me to take it to next weekends BEFA event.

13 Jun 01 - The plan for this model was included in the April 2002 issue of Radio Control Models & Electronics, with additional information and flight reports being published in the May 2002 issue.  I decided to fit the 2 Multiplex 450 Turbo motors I had available instead of the 2 x Speed 480 motors originally intended.  This will give me a little more power and the motors are more durable.  As the elevator is split, I also decided to fit 2 elevator servos.  This will allow the mixing of the 2 servos as tailerons, which being in the propeller wash should increase the manoeuvrability.  I have completed the construction and just await suitable weather for a test flight.

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