Highlight E

John Barnes

I've always found the first flight of a new model a voyage of discovery. Kits, built to plans, all moulded, it doesn't make the slightest difference. Early years experience of a very respected kit manufacturer's power model which was virtually unflyable when balanced as per plan taught me to take nothing for granted. But to this day, first flights have remained a thrill, particularly as some great models these days are devoid of information of any kind. Like the Highlight 2m Armageddon. Thick, low, dark purple clouds almost from horizon to horizon, a turbulent strong wind and light drizzle. Vehicle headlights on. Hard to remember that this is August in Scotland. It's 4pm. 8 miles away at the house the weather had been bright and almost windless, perfect for the first flight of Soarhigh's Highlight 2m span electric soarer.

The pilot is alone, gripping the fuselage in one hand at shoulder height while the Highlight tries to tear itself free. The model has a very strong fuselage, but now the pilot's grip is so tight to retain possession it feels like an eggshell. In the shop the model's 52oz mass had seemed substantive. Now it's an anorexic feather. These are less than ideal conditions for an exploratory first flight, balance and throws at a best guess setting. The small site is surrounded by tall trees, so the turbulence at ground level is significant.

"Go home, young Luke, it's too risky. There'll be other days". Wise words, Obi Wan, but would the world not be a greyer place without the odd spot of rash and impetuous behaviour to test the boundaries? "Yes, but it would have more models!"

Throttle on and heave, an eternity for the launch hand to return to the aileron stick. But no rush is required. The Highlight pulls away strongly, wings banging left and right but the model's path on rails. The climb angle steepens progressively as speed builds up. A little down elevator is fed in to limit the steepness of climb and maintain the model at flying speed, aileron corrections constantly required to keep the wings approximately level as an irritated Mr Turbulence continues the fight for possession. With this wind speed the model rises almost vertically, as if in an invisible lift.

Above 300ft Mr T. is left behind. Now visibility is becoming a problem against the spitting, angry, purple/grey background. For a few seconds the pilot stares at the point where the model - edge on from behind now - was last visible, then cuts the throttle and dabs in down elevator to hopefully level out. And there she is, about line height - c. 500ft for non thermal comp pilots wings silhouetted against Armageddon's screen saver. About 25 odd seconds have elapsed. Remarkable how tightly focussed concentration overrides the body's instinctive desire to breathe. Pheeeeeeeewwwwww.......!

The Highlight hovers, then dips and eases forward into another hover, another dip. A little down elevator trim is teased in to correct the stalling. Moving forward slowly now, she's banked left into her first turn. The nose drops, picked up with a little up elevator, and she rockets downwind. Another turn towards the pilot, nose dropping again. CG needs moving back. More climb outs, a high speed pass over the field at tree top height, a few loops, try coupled aileron/rudder for effect in the turns but lower down it's too blustery to be able to meaningfully check anything. 22 minutes after launch the model is landed, less than smoothly because the initial best guess setup for landing aid - both ailerons cranked up and flaps at 45 degrees, with a little down elevator compensation mixed in - is a complete mess!

Initial thoughts. Aileron and elevator control response is crisp, authoritative. Very little aileron stick movement used with the travels set, about 2/3 elevator stick for the fairly tight loops. A shrieking whistle from the high speed passes (surface gaps need shrouding?). The Highlight handled the conditions with ease. Solo launching an act of faith though. The wind strengthens, full size wind sock at the field maintaining an increasingly agitated horizontal pose. The receiver battery in the nose area is moved back 2 inches while the main pack is recharged. The landing mode settings are adjusted, flap deflection reduced and down elevator compensation increased.

The second flight is better, the change of CG making turns smoother, easier to fly. Penetration appears improved. The ship is still very stable though. An early landing as the sprinkle develops into darkening drizzle. Back at the house it's still much brighter and windless.

That was yesterday. Today, August 21 st, the tall trees around the house are bent in subservience to ever mightier winds. The forecast for the next week is that it will not improve. Soarhigh has been clamouring for customer setup information for the Highlight. Well, the fine tuning will have to wait, but perhaps enough was gleaned from the two flights yesterday to at least get the ball rolling. CG positions a matter of personal taste anyhow, the general rule for soarers being to simply balance it as far back as you're comfortable with. The balance setting used for the second flight yesterday is considered a good starting point.

For reference, this Highlight 2m has a root chord of 218mm - one panel is 219 but we'll ignore that - and a span of 1995mm. The motor is installed with the same down thrust as the fuselage profile but a whisker of right side thrust, the shaft line running about 15mm to the right of the tail centreline.

The control throws below are what were used yesterday. They are not optimised, perfect, spot on or anything else. Full stick travel was not reached for any control despite the corrections required for the turbulent conditions. Mr V. Average pilot was able to fly it smoothly though. A great start to the relationship.

Exponential was used on Aileron and elevator controls, 100% and 80% respectively (Mpx 4000 Tx). What this equates to in real money is that for aileron, 50% stick movement = 5mm down aileron and for elevator, 50% stick travel = ca 3.5mm up and down. For transmitters without an exponential facility, it might be prudent to use a little less control surface travel. How much less is not known yet.

Highlight E 2m settings

  • CG 85mm back from LE at root.
  • Aileron 10mm down 15mm up (100% expo)
  • Elevator 8mm down 9mm up (80% expo)
  • Rudder 8mm down 9mm up (no expo)

Landing mode (still far from perfect!):

  • Ailerons 15mm up
  • Flaps 10mm down
  • Elevator 3mm down
  • Motor Jeti Phasor 30/3 - direct drive
  • Prop Graupner Cam 12x6 folder
  • ESC Kontroniks Beat 40-6-18 (non BEC unit)
  • Rx GWS 8ch - Futaba crystal
  • Rx pack 720mAh NiMh
  • Flt pack 8x1200mAh 2/3 sub C nicads
  • Servos 6xRipmax SD150's
  • Weight 3lbs 4oz

Initial impressions? All positive. The Highlight looks like it'll make a cracking fun fly model, with soaring performance potential to make it a very useful tool in BEFA and BARCS Electroslot competitions, particularly on breezier days. As George Whelan has already discovered, the Jeti Phasor direct drive motors are very effective, quiet too without a gearbox. Current draw with the 12x6 prop is a very modest 24A average, both motor and pack barely warm by the end of a flight, so the pack can be recharged immediately.

Final tip: Don't leave the wing bolts at the field!