This posting is about my experience with two versions of the
tail/keel assemblies used by A.I.R. on our ATOS Rigid wings. The new “Full
Carbon Race Keel” and the older Carbon/Aluminum adjustable keel.
In 2018, I received my brand new VQR. The latest and
greatest “Race/Comp” version of the VQ. This evolution offered plenty of
innovation and “change”. Both sweep and hang point moved forward plus the
wonderful looking new Full Carbon Race Keel. The new keel and tail assembly had a dramatic increase in structural stiffness and substantial aerodynamic
dampening that included a new tail trim system, flap compensation profile and
elevated tail standoff (“T-Tail”).
My first flight impressions were good, the new configuration
proved to be a wonderful solid wing in rough air. The static balance was
improved (less tail heavy). Combined with
some nice new setup features, I was reasonably happy to have chosen the VQR. (Tho…
I was skeptical I was really looking at any performance improvement from my VR06…
mainly, a much nicer glider to fly).
“A much nicer glider to fly”…… thing is, everything that
goes up, must come down?
(For those who love their full carbon race keels, you might
want to stop reading this…I’m just a grumpy old man that decided not all the changes
to my ATOS were good, as they say… “in my opinion”)
Almost immediately, I noticed my landings had taken a turn
for the worst. I soon found my timing and
feel were gone and I was no longer arriving with any sort of “grace or style”…
often I was arriving like a box of rocks 😉 (usually on the skids). I also became aware that a few others in our
small community also started to report the same issues with the full carbon
race keel,
Many in the community mentioned exploring other techniques
to improve the landing. Less flaps (not
landing with the factory recommended “full” flap setting). For me, this worked
reasonably well but the technique did not give me much confidence in the wing
as I was still plagued with inconsistency. Some pilots resorted to landing on
the control bar skids (certainly not an option for us desert pilots). Many would describe the landing issue as: “I got near the ground and the glider just
quit flying”.
I should be clear, I can accept that many pilots successfully
master the new carbon race keel but I for one struggled to make it work. So
much so, I considered simply reverting to the much friendlier VQ, A.I.R.’s “intermediate”
performance wing. I made the decision to
sell the VQR and was prepared to order a VQ when I decided to dust off my old VR06
for a local XC (a test flight to confirm its airworthiness for a new owner as
this glider was also “sold”). The flight ended with a perfect landing and
leaving me asking the question, why so much difference between the VQR and VR06?
The best way I can describe what I believe to be the
shortcomings of the Full Carbon Race Keel would be to put forward the understanding
that ALL of the ATOS wings are by design, “Flying Wings”. Through their evolution
the various models have developed varying levels of dependence on a “tail” to
create desirable flight characteristics. From a fix position tail of the early
V and VQ to the variable pitch design of the VR, all demonstrate varying levels
of dependence on the tail.
The Full Carbon Race keel introduced with the VQR and late
model VR’s with substantially greater stiffness and dampening allowed the Race
model wings reduce sweep and move our ATOS wings closer to a “hybrid” flying
wing, a wing that is now reliant on the tail for overall flight stability. You
could say, we are getting closer to that of a conventional sailplane?
The issue as I see it is, our pitch control is weight shift and
the tail remains a dampening device and not an elevator as found on our
sailplane cousins. When we come into
land, our only pitch control is weight shift.
This evolution and reliance on the tail for pitch dampening has become our
Achilles heal. All of the wonderful flight characteristics of the new keel
work against you when it comes time to land.
Another deficiency created by the design and the reduction
in wing sweep is the forward hang point (4-6” further forward than earlier models). At the same time, the
control bar apex remains unchanged. The benefit of this configuration is
improved static balance (I admit the old VR06 was a beast for being tail heavy).
When going upright to land, the control bar is effectively 4-6” further back.
Any downward load on the upper portions of the DT’s (pretty normal when getting
a comp harness upright) will be “at” or “behind” the hang point and certainly
not helpful for maintenance of your approach speed (so much so, the new Full
Carbon Race Keel tail position has an additional movement, with full flaps, it pitches
the nose down to assist in landing trim…. All contributing to a pitch stability
that is as solid as concrete 😉)
As I mentioned, I’m sure there are a crowd of pilots out
there that are more than happy with the Full Carbon Race keel, but for this old
guy the change wasn't working out and I just could not seem to figure it out...
In Spring of 2023 I received my brand-new ATOS VR14. When I
ordered this wing, I ordered it with the original Carbon/Aluminum Keel (same
keel as found on the much older VR06). With my very first landing on this wing,
my theories involving the Full Carbon Race Keel were reenforced. The first landing
was without drama, super easy to maintain trim on approach, predictable landing
feel and a pitch that easily reacted to my landing inputs. Truth is, I was shocked
just how easily the glider landed!
Ok, is the older version keel perfect? Nope… it’s probably
not for everyone. You will find the VR14 substantially more nervous in pitch. You
feel more in rough air. Pitch tends to wander in the “bumps”, plus many may
have trouble with the near zero bar pressure when the flaps are pulled up and
you head out on glide… I compare the VR14 to a race car that has character… and
I love it.
Of course, over the original ATOS racing machine, the VR06,
I have benefited from many other good design improvements such as, the small
flaps (cleaner and easier to pack), the new quick setup, the updated nose catch
system, feels less tail heavy and is a massive reduction in weight (nearly 15
pounds less than my old VR06). The weight reduction shines through when rolling
into a turn as the glider has a much-improved roll rate. I also enjoy getting back on a glider with
winglets, not only sexy looking but they really bring back a confident feel to track
on glide and a super solid feel in big thermal air.
Some comparison between the two keels versions (this came as
a bit of a surprise…), both keels are as best as I can tell are the same weight
(roughly 10 pounds without DT’s or tail feathers). The Full Carbon Race keel is roughly 14”
longer from CB apex to Tail feather LE and nearly 20” longer from hang point to
Tail feather LE. Oh… and the Full Carbon
Race keel is going to cost you 2000 Euros more… (important to a cheap sod like
me 😉)
The VR14 is likely my last wing from A.I.R. as I suspect I
have only a few more years left before I finally “grow up” and find a real hobby!
That said, I think the VR14 is the perfect choice to take me through to my
retirement from the sport… in 4 or 5 years (???).
I’m pretty sure A.I.R. won’t really care what this one grumpy
old guy has to say about their product. My only advice to the crew at A.I.R. is,
when spending time trying to make the glider fly better, don’t forget eventually,
you will need to land it….
For the Full Carbon Race Keels owners that have adapted their landing
techniques, and are likely happy with the benefits of the keel, koodoos to you... . My buddy “Mike”
from Spokane who has mastered his landings on his VQR claims all you have to do
is run like somebody is “chasing you with an axe” LOL….can’t argue as his landings
tend to be text book perfect. To others that may find yourself struggling, consider
getting a test flight on the VR14 with the original keel or even the stock VQ .
You might be pleasantly surprised.
If you have a Full Carbon Race Keel and you want to stick to
your choice (but you have been landing like a “box of rocks”) it’s probably
just technique.… like Mike says… think about that guy chasing you with the axe 😉.
Cheers!
