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1. Summary |
by Jérôme Daoust. Revised 2002/12/28. |
Summary (Top of Page)
Thanks to Alan Bradley (Nova USA, E-mail) for supplying this test wing. This section is a summary of my experience, some of which described in the Daily Notes. This test immediately (next day) followed that of an Aeron M.
· Model flown, Medium (25), has a 85 to 105 kg weight range. My total flying weight was 99 kg (70% into the weight range).
· See Daily Notes for flying conditions and more detailed notes.
· The harness used is a Sup’Air EvoTop, with 20 cm Bump’Air protection, and a chest strap set at minimum length (maximum relaxation, sufficient feedback and weight shift to my taste). Riser separation (between bottom centers) was 41 cm.
· No aerodynamic-enhancing device (tight sleeves or pants, formed harness shape) was used.
· Deliverables.
o Wing, line and riser assembly.
o Yellow helmet bag.
o Speed bar with a first step wire loop. Speed bar accelerator line.
o Small windsock.
o Wing strap and bag.
o Carrying bag, which in my opinion is the best in the industry. Wing, harness with 20 cm Bump'Air, helmet and extra clothing easily fit.
· Risers.
o Simple system of 3 risers : A (split), B, C.
o Brake snaps are non-magnetic. I prefer that.
o Brake pulley is large, I suspect a ball-bearing mechanism. Pulley is stamped with the words : Holt-Allen, England. The pulley is attached to the last riser (unlike the Aeron).
o The accelerator line attached to the riser, ends with a Brummel hook, being braided back on itself, instead of the usual stitching. This allows the line to feed back completely into the pulley, and have the hook next to the pulley. This provides more travel potential for accelerator travel, before the Brummel hook meets with the harness pulley.
· Wing.
o Top surface has that waxy feeling to the touch of Gelvenor fabric.
· Moderate wind (10 km/h). Very easy inflation and kiting. Almost a beginner wing in this respect.
· No hard-point noticed during inflation and rise of the wing to an overhead position.
· Nothing to declare.
· Stability. No collapses during the rough conditions. A wing I can definitely relax under.
· Collapse recovery. From trim speed, frontals and 50%-ers are benign.
· Thermalling.
o Agility. Defined as the ability to ease to stay in sharp-edged lift that wants to push you out its side. Low agility may force a pilot to explore the limit of brake pull prior to inducing a spin. My scale of 0 to 10 :
o 0 for an Apco/Presta M at the bottom of its weight range.
o 5 for a Nova/Carbon.
o 10 for an Advance/Omega 4, Gin Gliders/Oasis or Independence/Dragon.
I rate this wing as a 5 (like the Carbon). I would qualify the agility as sufficient/adequate. Even with sharp brake pulls to stay in lift, not spin initiation was observed.
o Brake input. Brake pull is smooth with a gradual increase in tension. Overall brake tension is average to high. Very easy to thermal with inside brake alone (I like that). The wing does not dive into a spiral dive, if we maintain the brake pull that initiated a decent turn (I like that).
o Feedback (41 cm riser separation). Ample feedback was available through asymmetric pull of the risers.
· Inflation and kiting. Very easy.
· Very relaxing. But I would say the same of just about any DHV 1-2 wing.
· Performance seemed good for a DHV 1-2 wing. Best of class ? Wait and see.
Daily Notes (Top of Page)
2002/12/27
· Site : Marshall. 2 hours 15 min airtime. 10 km/h wind (when I launched). Best climb rates of 6 m/s (with sharp edges). Multiple climbs to 750m above launch. 1 top landing, condition where that of a local convergence. Pilots could no longer launch shortly after I did due to dust devils, and the main breeze switching to come from the back. No relative comparison could be made.
· Stability. Worst turbulence felt was 8/10 on my personal scale. No collapse which were not self-induced. A wing I can definitely relax under.
· Induced collapses. I was left with a very comfortable feeling (very slow overall movement of the wing overhead) :
o Two frontal at trim speed. Rapid recovery without intervention.
o Two 50% collapse at trim speed. Typical input, wing turns 1/8 turn. Benign.
· Big Ears. From trim speed : Stable configuration. After full acceleration : Stable configuration. Ears stay in by themselves.
· Accelerator. Very smooth action. Feeling of typical DHV 1-2 dive, but no sharp "knee" observed in the polar curve. I did a transition of about 2 km into the wind with ½ speedbar, and glide felt good for a DHV 1-2 wing.
· Thermalling.
o Agility. Defined as the ability to ease to stay in sharp-edged lift that wants to push you out its side. Low agility may force a pilot to explore the limit of brake pull prior to inducing a spin. My scale of 0 to 10 :
o 0 for an Apco/Presta M at the bottom of its weight range.
o 5 for a Nova/Carbon.
o 10 for an Advance/Omega 4, Gin Gliders/Oasis or Independence/Dragon.
I rate this wing as a 5 (like the Carbon). I would qualify the agility as sufficient/adequate. Even with sharp brake pulls to stay in lift, not spin initiation was observed.
o Brake input. Brake pull is smooth with a gradual increase in tension. Overall brake tension is average to high. Very easy to thermal with inside brake alone (I like that). The wing does not dive into a spiral dive, if we maintain the brake pull that initiated a decent turn (I like that).
o Feedback (41 cm riser separation). Ample feedback was available through asymmetric pull of the risers.
· Energy retention. Seems average, typical of DHV 1-2 wings. Wing-overs are accomplished without too much effort.
· Inflation and kiting. Very easy inflation and launch in the 10 km/h wind on launch. After top-landing, wing was easy enough to kite overhead while talking to someone for a short while.
· Top landing. I did one in light wind, and it was uneventful.
· Landing. Moderate/Strong wind (about 25 km/h) was in the LZ. I pulled the B risers just prior to touching the ground. I was surprised by the amount of pull necessary. Maybe because the B line affect a greater surface of the wing through chord-wise division of lines ? Hard to conclude from a very short-timed event.
Rumors (Top of Page)
The following is unverified...
According to the manufacturer, the best L/D (Lift/Drag) should be similar to a Nova/Argon with regular lines. Looking at past reviews of the Argon, and some conservatism (0.1), I expect 8.35 for its best L/D. This figure would place the Artax amongst the top performers in the DHV 1-2 category. Contenders in straight-line performance would be the Airwave/Sport, and Flight Design/Stream.