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1. Summary |
by Jérôme Daoust. Revised 2009/3/24 |
Summary (Top of Page)
This section is a summary of my experience, some of which are further described in the Daily Notes.
Special thanks to:
§
Alan Bradley (Nova
§ Hannes Papesh (the wing's designer), for answering my questions on the wing's design.
· Total airtime : 78 hours, as of 2005/9/3.
· Model flown, Medium, has a 90 to 110 kg weight range. My total flying weight was measured at 224 lb (101.6 kg) (58% into the weight range) where 50 lb (22.7 kg) was equipment, including 1 lb (0.45 kg) winter pants.
· See Daily Notes for flying conditions and more detailed notes.
· The harness used is an Airwave / Ram Race, and a chest strap set at minimum length (maximum relaxation, sufficient feedback and weight shift to my taste).
o Same wing weight (6.5 kg), same weight ranges.
o 2 less cells (55 instead of 57).
o Less projected wingspan, surface area and aspect ratio.
o Less "flat" wingspan, surface area and aspect ratio.
o Aspect ratios (projected and flat) are now the same for all sizes.
o More line length (wing is 34 cm further from pilot) and total line consumption.
o Same max profile depth.
o Higher min profile depth.
· Hannes Papesh, 2004/10/21:
o After trying around with the Aeron concept, we realized, that we have to find an absolutely new concept to reach our goals. So we made some experiments with different ground shapes, wing curves, sail tensions (the trailing edge is a knife) and airfoils (off course the computer told us, what will make sense and what not).
o Finally the Tattoo has nearly all different compared to the Aeron: more wing curve, a less fragile wingtip, longer lines, new airfoils, much different sail tensions.
· Hannes Papesh, 2004/10/30:
o There are some differences between Aeron and Tattoo: Stabilo has one less cell (per side), profiles, sail tensions, canopy curve, line length, some internals (holes, diagonals..), line geometry (the Tattoo has main D lines).
o What remained the same: Sweep angle, position of intakes, some materials (not all).
· Deliverables.
o Wing, line and riser assembly.
o Windsock.
o Speed bar, lines, and Brummel hooks (Sister clips).
o Transport bag.
· Risers.
o Picture of left riser set. Nice ball-bearing brake pulley, with view of balls.
· Lines.
o Small diameter red line leaving B riser: Picture of left riser set. Probably going to the wing tip.
o I don't remember seeing unsheathed lines.
· Wing.
o Top surface has that slippery feel.
o I like the black leading edge on the Yellow color scheme.
· Accelerator system.
o On 2005/1/13, I made a few measurements to anticipate what would be the required correction to my accelerator lines going to the speed bar, in comparison to my Aeron, and using an Airwave / Ram Race harness. The Brummel (sister clips) are 6.5 cm higher on the risers, and there is 8.5 cm more travel required of the speed bar (33 cm travel). Net result is that I should shorten the line by 2 cm, but I will hold off to see what happens in flight. I am not concerned about the travel of the Brummel hooks, as the Airwave / Ram Race harness has plenty of margin there. But when flying with the Aeron, the accelerator lines had maybe 5 cm of slack (from memory) when at trim, so the 6.5 cm higher relocation may produce taut accelerator lines from the speed bar being pulled up to the harness. So shortening the lines even more would not be a good idea before getting a verification flight.
o QA (Quality Assurance) issue: The accelerator line (attached to riser, not the speed bar) on the right riser is 2.4 cm longer than the one part of the left riser. I wasn't sure if this was dues to closer pulleys or the actual lines, so I verified that the pulleys had the same distance on both side and verified the actual line lengths. No a big problem because my Airwave / Ram Race harness has ample room before the first harness pulley and I can correct by adjusting line lengths going to the speed bar.
o 2005/1/15. In flight verifications revealed that I still is 3 cm (eyeball measurement) of accelerator line slack at trim (speed bar not used). I also did an eyeball measurement of the distance remaining to achieve riser pulley contact when legs fully stretched: 1 cm. Since the riser pulley ratio is 3:1, I should be able to achieve full accelerator use by shortening lines by 3 cm (done on 2005/1/16), while have zero slack in the lines when speed bar not in use.
o Open request to manufacturers: Please limit your accelerator line travel to 25 cm, as 30 cm is on the edge of creating problems. The Tattoo consumes 33 cm and I have no margin left for achieving slack lines at trim and maximum acceleration. People with short legs may have yet more difficulty.
o 2005/1/22: My latest adjustments were as good as possible. In flight at trim, the accelerator line have about 0.5 kg (1 lb) tension and about 1 cm can be used before tension starts rising sharply to pull down the A riser. I am not able to achieve pulley contact when pushing the bar near the heal of my shoes, but when pushing closer to the toes, I can achieve riser pulley contact. Still, I don't like the lack of adjustment margin.
· Transport bag.
o The transport bag is completely different from previous Nova bag. I will leave that issue aside for now as I don't plan to use it until I commit to purchase the wing. But I would not use it anyway because the hood cinch straps would most likely compress the 2 Ram Air inlets of my Airwave / Ram Race harness (better to have one central in this case).
· On 2005/1/14, I did a few inflations in light wind (0-5 km/h) and the wing behaved well.
· On 2005/1/15, I did one landing, being somewhat deep in the brakes to test the mushing (able to use the higher sink rate at slower than min sink speed) ability. And the wing did not stall, so there is hope that one can use mushing if needed.
· Stability.
o See Daily Notes for more detailed reports on stability (look for that word in bold).
o Hannes Papesh, 2004/10/21: Compared to Aeron: Better safety and more comfort: So suitable to more pilots because in the middle of class 2.
o At trim speed, I am under the impression this wing is more nervous overhead than the Aeron (less dampened in pitch). I am thinking that a reduction in dampening at trim could be contributing to the higher agility noticed. I am only considering this as a preliminary impression, which will need to be verified with more airtime.
o Pablo Lischinsky, 2005/1/19 (pablonoldo AT cantv.net): Subject: Aeron à Tattoo ;-). I've been flying my new Tattoo for about 40 hours now, mostly in thermal conditions (competitions: Mérida-Venezuela Open Andes 2005, Roldanillo-Colombia Pre-PWC). I have no measures, only some feelings after flying the Aeron for 18 months. The overall evaluation result for me is that I'm VERY happy with the Tattoo and that I feel that in effect it is a big step forward in performance and handling - thermalling, more fun and very solid in turbulence.
o Rate of collapse:
§ Frontal collapse: 2 at trim speed. Rate in rough air: 1 per 2 hour. My impression: More than expected.
§ Asymmetric collapse: 1 small one (20%). Rate in rough air: 1 per 4 hour. My impression: Less than expected.
· Collapse recovery.
o DHV Test Report - NOVA Tattoo M.
o Hannes Papesh, 2004/10/21: The airfoils collapses softer compared to the Aeron. It was not necessary to change the trim for the certification: It's still the computer calculated (performance optimized) one.
o On 2005/1/15, I induced some max speed (full speed bar) collapses, as I believe this is the most typical worst-case scenario collapse for XC pilots.
§ Frontal at max speed. Surprisingly soft recovery. I would give it a DHV 1-2 rating as it compares to what I have seen on a Gin/Oasis or Nova/Artax. But DHV gave that maneuver a 2, so what do I know?
§ 50% asymmetric at max speed. Picture by Zach Hoisington. The first one I did, the brake toggle on the hand I used to pull the riser, popped-out of my hand because I was holding it too lightly with my fingers. I repeated a second time, without letting go of my brakes. Both exits were similar, with lateral diving amplitude similar to what I have seen when doing this maneuver with the Aeron. A true DHV 2, but nothing out of the ordinary.
· Big Ears.
o Compared to the Aeron, which was unstable with big ears at max (full speed bar) speed, the Tattoo was stable over the time I kept it in this configuration.(5 to 10 s).
· Accelerator.
o Hannes Papesh, 2004/10/21: In contrast to [its thermalling agility] it's getting really fast and very stable when you push the speedbar. The wing has 4 risers and a very long speed travel.
· Thermalling.
o Hannes Papesh, 2004/10/21:
§ Compared to Aeron: Much better handling: less brake pressure, reaction on less brake travel, more agility, a more rigid canopy, easier to turn even in strong thermals.
§ Brake geometry adjustment is always a matter of taste in special conditions. We had a brake [geometry] for very weak thermals and another one for strong and narrow thermals. Finally we found a good synthesis between performance and fun. It also depends a lot on the harness and the weight shift input.
§ The Airfoil has an impressive bite even in weak thermals. The thermalling performance is one of the best we have ever made possible.
§ It has much less brake pressure.
§ The wing is only little smaller but gives the impression to fly an S because of higher agility.
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 :
§ 0 for an Apco/Presta M at the bottom of its weight range.
§ 5 for a Nova/Artax.
§ 6 for a Nova/Aeron.
§ 10 for an Advance/Omega 4.
I rate this wing as a 10. Maybe even better than my old Omega 4. See Daily Notes for more information.
o D lines go slack:
§ Initiate a hard turn and watch the D lines go slack and into the brake line fan. Not so much of a problem, as a curiosity.
o Performance:
§ When releasing from a turn (up-wind phase in a thermal) I could feel significant climbs from the energy recovered from the higher-banked turned. The combined (seemingly) good sink rate, energy recovery and verified high agility, makes this wing an efficient thermal climber.
· Performance (straight-line).
o Hannes Papesh, 2004/10/21: Compared to Aeron: Of course, better performance in glide, sink and practical thermalling. The airfoil and the sail tension are enabling better performance even with a little less projected aspect ratio. Trim speed is nearly the same as Aeron. Max speed also.
o Hannes Papesh, 2004/11/2: We have to measure the glide in perfect conditions. When we made the last comparisons in Bassano, the conditions were not very good (still some turbulences). There we only noted, that the X167 (Tattoo M proto) is better performing than the Aeron, but we could not tell how much. I'm also expecting a little performance gain with the production wings, cause they're a little cleaner than the proto (serial patterns, accurate cut).
o Hannes Papesh, 2005/1/17: The high-energy retention in wingovers makes flying 8 figures near the ground (when soaring) more efficient.
§ 2005/1/17. Now that you mention it, I did figure-8 maneuvers to stay in narrow lift near the ridge, and this seemed efficient.
o In flight comparisons.
§
2005/1/15.
Compared to an
§ 2005/1/15. Compared to a Gin/Oasis M. I have flown next to the same pilot before with my Aeron, and we also had similar trim speed, making this a good benchmark. Again with the Tattoo, we had similar trim speed. So it seems that the Aeron and Tattoo have similar trim speeds. For fun (I knew I should have an advantage) we did a max speed (full speed bar) L/D comparison and noticed that while we had similar sink rates, I had significantly more speed (maybe 4-5 km/h).
§ Dimitri Keller, 2005/1/16: The Tattoo at trim has a 1-2kmh advantage over the Brontes (but my harness is not very aerodynamic like yours). I'm hooked in at 105kg. From my point of view your wing required very little input to make a turn. And it didn't "dive into it.
o Max speed L/D.
§ 2005/1/15. Did 8+ fully accelerated short glides. General sensation of good glide, without dramatic drop in sink rate. Just an impression, no measurements.
o Speed.
§ Trim, at sea level, with 50% into weight range, at 15º C (59º F): 37 km/h. See Daily Notes for 2005/1/22.
§ Max (full speed bar), at sea level, with 50% into weight range, at 15º C (59º F): 51 km/h. See Daily Notes for 2005/1/22.
· Braking.
o A few times, I was surprised to see how much brake travel was being used, with low tension for the given pull amount. Maybe those who like low brake tension will enjoy this. Still, the wing responds willingly to normal amounts of pull, it just seems to require less tension. Or maybe I just had extra strength while flying a new wing for the first time? Those multi-vitamins finally kicking in?
· Aerobatics.
o Hannes Papesh, 2004/11/30: Our Swiss importer Urs Haari mentioned, after he tested the Tattoo, that after deep spiral dive release, wingtip collapses could happen. This is caused by the good performance of the wing: after spiral release it rises up until it hits it's own turbulences. Also Mike Küng mentioned that after spiral release it rises up a lot. Please just keep that in mind.
§ I got first-hand experience. See Daily Notes for 2005/1/22.
o On 2005/1/15, I did some wing-overs. Compared to the Aeron, this wing does not dampen much the amplitudes, and you can surprise yourself by going "bigger" than expected.
· Compared to the Aeron:
o Better. Better thermal climbing ability. This wing is more willing to translate kinetic (speed) energy into potential energy (height). Figure-8 turns close to terrain become more efficient, as well as bank angle adjustments while thermalling. Leveling-off from a banked turn, results in a significant climb.
o Better. I seem to get less asymmetric collapses than expected.
o Better. Frontal collapse recovery is softer.
o Slightly Better. Incremental polar curve performance improvement. I trust the designer here, as there is not enough of an advantage to be obvious in straight flight (expected). I have the impression there is less sink at max speed, but I also changed to a Airwave / Ram Race harness recently which will account for some gain.
o Same/Unsure. Rate of frontal collapse: No conclusion reached at this point. See Daily Notes for more info.
o Slightly worse. Wing seems more nervous overhead (less dampened) at trim speed. Reminds me of my Omega 4 (Old DHV 3). This may be due to the better energy retention (listed above as a quality).
o Worse. Accelerator system requires 33 cm of speed bar travel. That can be a problem for some, at the limit of usability for me.
· Capturing the essence of the Tattoo: A no-gadget wing with high energy retention, offering top-of-class performance.
· Contenders :
o Nova / Tattoo C. It has a hybrid line set.
o Advance
/ Sigma 6. Performs equal to regular
Tattoo according to Thermik magazine.
o Airwave / Mustang. Performs less (0.2 L/D) than regular Tattoo according to Thermik magazine..
o Gradient
/
o Skywalk
/
o Ozone
/ Instinct. Soon available, available in regular/unsheathed lines. Performance?
o Icaro
/ Ice 2 XC. Available but no performance reports.
o Apco
/ Lambada. Available but no performance reports.
o Pro-Design
/ Thema. Performance?
· Aiming for yearly replacements, I was overdue for replacing my Aeron, so I purchased the Tattoo. I hope other DHV 2 wings keep raising the bar in 2005, as I will be shopping again at the end of 2005.
· Pictures in the Daily Notes.
Daily
Notes (Top of Page)
Does not mention all my flight, just whatever I worth reporting.
2005/1/13
· Received a Medium Tattoo for testing.
2005/1/15
· 2 hours airtime at Elsinore. 80% ridge soaring, 20% thermalling.
· Stability. 20 km/h cross-wind producing some turbulence. I got one frontal. I flew a lot close to terrain but was active then out of concern of potential collapses. I got one frontal at trim speed, when I was high (too relaxed?) and flying towards a wind-protected bowl. I felt a sudden lift and drop, unloading the wing. The collapse recovered without input required. The wing stayed on its flight axis and did not loose much altitude in the process. No other pilot close to me at that moment, to later compare notes on turbulence level impression
o Dimitri Keller, 2005/1/16: I got two frontals at the same place that you did (very mild on the Brontes). And I have seen one of yours. Looked like "Leading edge flutter" and it reopened very quickly ( 0.5 seconds max).
· Agility. The Tattoo was actually fun to put into a quick turn from a straight-line flight, and able to quickly achieve a fast rate of turn. But at the same time, the wing does not want to keep accelerating into a dive, preferring to keep a constant bank angle for the corresponding inner brake pull. External braking was not required to stabilize the bank angle. Twice, I left my wing being pushed out of lift from a moderate roll push, but was able to re-center with simple addition of inner brake pull (did not observe a spin tendency). A significant improvement over the Aeron.
· Pictures (thanks guys):
o Bob Barry.
§ Side view. The leading edge near the tip looks sharp.
§ Thermalling.
o Dimitri Keller.
§ On glide.
§ Bottom view.
o Thomas Soudek.
§ Ridge soaring. Nice leading edge near the wing tip.
§ Gliding.
§ Thermalling.
§ Landing.
o Zach Hoisington.
§ Asymmetric collapse on full speed bar. Yes, it was done on purpose.
§ Distant snow-caped mountains. Thermalling.
§ Side view.
§ Tail view. Where did my lift go?
§ Top view. Thermalling.
2005/1/22
· 2 hours 9 min airtime at Kagel. 90% thermalling.
· Conditions were summer-like, with lots of rough air when close along the spine to the right of launch to find lift. In the worst of it, I rate it as a 8/10 on my turbulence scale (0 is smooth air, 5 is my criterion for seeking smoother air, 10 is at limit of flyable).
· Stability. I got one frontal when scratching low on the ridge known to produce rough air. Normal recovery. I would not say this is an unjustified collapse, as I was accepting more risk by knowingly placing myself in an area where I may have a change to regain altitude. I was the only paraglider pilot flying at that time, 4 others sank out earlier, and I top-landed later to fly some more with the group that would return to launch (more fun to fly with friends).
o Dimitri Keller, 2005/1/22: I had lots of surging on my Brontes.
· Stability. I got one 20% asymmetric (first not intentional) when thermalling. I just ignored it and kept turning to the other side into the thermal. Wing recovered normally by itself within a few seconds.
· Airspeeds. At the end of the day, I maximized altitude and when on a long glide into stable air to measure airspeeds using a cheap Skywatch/Fun instrument but known to be within 1 km/h of more expensive instruments I used in the past. My measurements (each averaged over about 30 seconds of stabilized flight):
o Trim. 38 km/h (values seen ranged from 36-40) at 1300 m MSL. Correcting to 50% into weight range (from 101to 100 kg), temperature (From 66 to 59 ºF), and altitude (1300 m to 0): 37 (36.9) km/h at sea level.
o Maximum (full speed bar). 52 km/h (values seen ranged from 49-54) at 1200 m MSL. Correcting to 50% into weight range (from 101to 100 kg), temperature (From 66 to 59 ºF), and altitude (1200 m to 0): 51 (50.8) km/h at sea level.
· I hit my own wake after doing a spiral dive (Competino showed -10.8 m/s in its flight summary). After doing a smooth exit into a direction away from the LZ, I then did a ½ turn to go towards the LZ (and the axis of my spiral dive) and encountered unexpected rough air. A moment later I realized what had happened: I had hit my own wake from the spiral dive. Air was otherwise very smooth with light wind (about 5 km/h), so this is the most likely explanation of the turbulence.
2005/2/26
· 3 hours 20 min airtime at Torrey Pines. 90% ridge soaring, but with 2-3 thermals taking me to 200 m (650') above launch.
· Launching in strong wind (25-30 km/h) was uneventful.
· Tattoo M -VS- Sigma 6 size 28 :
o I got to fly alongside (in smooth ridge lift) with 2 other pilots which were testing a demo Sigma 6. Here are my airspeed observations…
o Wing loadings: I'm 58% into the weight range of the Tattoo M. A local distributor (Frank) had a demo Sigma 6 (size 28, 85-110kg) which was flown by 2 test pilots:
§ Pilot A (Turbo Bob). 100+% into weight range, maybe exceeding max recommended.
§ Pilot B (Jayson). 64% into the weight range.
o Both test pilots were asked to go fly alongside me for comparison. Good idea…
o Max speed comparison: Same fully accelerated speed as pilot A despite his significantly heavier loading! Pilot A agreed with observation. Pilot B complained about not being able to use full range of speed bar and was slower.
o Trim Speed comparison: Pilot A had 1-2 km/h advantage (normal due to heavier loading). Pilot B had exact same trim airspeed (we were very close to each other and a difference would have been obvious), and agreed with my observation.
o Conclusion from these 2 comparison tests: Tattoo is as fast, or more, than Sigma 6 for same loading within weight ranges, both at trim and fully accelerated. I was expecting the reverse (marketing), so this was a pleasant reality check.
· Did lots of wing-overs. The energy retention and agility made them very enjoyable. I was paying special attention to the brake line tension on the wing's high side, and the upper tip did not seem to want to collapse during the maneuvers. Nice.
· Pictures (thanks guys):
o Bob Barry.
§ Going North, next to the mansions.
2005/9/3
· After 78 hours airtime on this wing, I switched to a Tattoo C.
Testing Expectations (Top of Page)
Why I am testing this wing :
I need to replace my aging Aeron, and although I wanted to do it sooner, I have
not yet found a suitable replacement.
What can be done (by order of importance):
o Does the wing keep increasing its bank angle, past what the initial turn response lead me to expect ? I don’t like a wing that seems to screw into a spiral dive after a moderate turn initiation. No=Good (2005/1/15).
o Can internal braking alone, easily regulate the bank angle ? I don’t like to use external braking for this purpose. Yes=Good (2005/1/15).
o Sufficient agility to feel safe from inducing a spin. Yes=Good (2005/1/15).
o Am I getting many more collapses that the others I fly with ? Unsure, need more airtime.
o Decent recovery from accelerated collapses: frontal and asymmetric ? These 2 events are likely to happen during ownership, so if I don’t feel comfortable enough inducing them under controlled conditions, I should not be flying this wing. I don’t need to re-certify the wing (perform all test or repeat them many times), just gain some trust from the recovery behavior under accelerated flight. Yes=Good (2005/1/15).
o Verify stability. OK (2005/1/15) but with 1 cm missing for pulley contact.
o In combination with Big Ears, verify stability. This technique is useful for escaping cloud suck. OK (2005/1/15).
o Can I bring the wing overhead in null wind ? Yes=Good (2005/1/14).
o Does the wing have a “hard point” during inflation ? No=Good (2005/1/14).
o Is it easy enough to kite the wing ? Yes=Good (2005/1/15).
What will not be attempted :
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