The Style:
Originally intended for FUN
flying with the boys on a Sunday afternoon, VTPR is fast becoming popular in
the US. This fun style of RC slope flying is basically aerobatics very close to
the ground with varying model air speeds and design. Since its inception over
two decades ago in France it has now become quite sophisticated beyond merely
fun flying. It is approaching a competitive spirit that is producing new model
designs in the US being flown on many geographic slope contours as well as
becoming more and more precisely descriptive in its understanding.
At the moment the Americans
are actively exploring this sport over what exactly VTPR is. We are seeing all
kinds of new aerobatic maneuvers from ultra-light and the typical medium weight
models from novice to expert pilots. The VTPR movement in the US is in a state of
growth. Two styles have emerged as favorites, that being traditional French
VTPR and an American style VTPR that encompasses tighter and quicker maneuvers.
Regardless of which style is preferred the following core tenants of VTPR
remain the same.
As per Pierre Rondel in 2005
he quotes: "But more what we call in
France VTPR - Voltige très près du relief (translation: aerobatics very
close to the ground), this is a very
spectacular type of aerobatics that requires very good skills and no
fear".
And from the author I quote: "Any aerobatic maneuver, figure or
trick interpreted by the pilot that is performed successfully, and in whole
directly above and close to the terrain, at any desired air speed". Example:
2 half rolls in succession at eye height or around one and a half wingspans
or lower to the ground is a VTPR maneuver.
What VTPR is not:
Maneuvers, figures and or tricks performed beyond the slope lip in open air space or far away from the terrain. Far also means figures above 3 wingspans at their lowest point. These maneuvers should be termed as "Aerobatics Totale".
Maneuvers, figures and or tricks performed beyond the slope lip in open air space or far away from the terrain. Far also means figures above 3 wingspans at their lowest point. These maneuvers should be termed as "Aerobatics Totale".
The dividing line between VTPR to
Aerobatic Totale style can be clouded and very opinionated. One can drift in and out of VTPR during a single flight but its important to note, the French built the core VTPR principle around these four simple
words - Low, Lower, Lowest & Fun.
The Models:
VTPR gliders range in wingspan
from 1.5m to Unlimited and are designed with very light and durable airframes
made to cut the air and choreograph some of the most amazing maneuvers ever
seen. They enjoy confronting danger and succeeding in delivering a very
reliable stance all the way through the extreme moves that a pilot can muster.
They like to hover, stall roll, perform off angled figures and just about everything
under the sun one can imagine. They particularly perform with grace and beauty
in all positions. Its important every square inch of the model be designed and
built in such a way that purposely accomplishes performance with ease at all
times. All summed up, we want a VTPR model that will seem to defy gravity
during flight as if it were dangling from a string. The ultimate goal is to
design a plane that makes it easier and easier for the pilot to fly difficult
and dangerous maneuvers hence these models are in a constant state of development.
The Slope:
Every form of model glider
flying requires a particular space and proper conditions suited to obtain the
maximum performance the model is designed for. Not all gliders are alike by any
means and are strongly defined by the environment they perform in. This is
especially true of VTPR style of slope flying. Some slopes are better than
others for the best looking VTPR result. Particularly with very close to the
terrain slope aerobatic maneuvers we
want a slope to have certain wind and lift conditions for success or disaster will
result with a broken plane more often than not.
For general slope
identification and shape there are three basic types of slopes covered here to
help you visualize and understand their positive and negative VTPR traits.
Added to the slope geography is wind direction, wind speed, temperature and
atmospheric pressure considerations the novice VTPR enthusiast would do well to
learn as he gains experience.
Slope #1
This simple graphic below shows the
most desired slope contour and wind direction characteristics in order to perform
VTPR aerobatics to the fullest and easiest degree. A nice long shallow slope
with lateral wind direction flowing over the glider wing is the most efficient
for VTPR. The "fly box" is large and open for all manner of VTPR. To
the common slope flier this may seem odd or not what they have learned and flown in slope for many years.
Perfectly understandable but we want to fly very close within inches of the
ground at times in which the near horizontal wind forces net us the best
result. When entering close to the terrain you will find with practice this is
in fact what we VTPR flyers desire the most in a slope.
Slope #2
Below we can see the more
common inland slope contour you are probably very familiar with. The 45 degree
or so slope angle causes the oncoming wind to propel upwards and over the slope
creating an upward lift band and rotors behind the slope lip. This at first
glance looks like a nice flying slope and it is for general flying and
aerobatics. But in the context of over ground VTPR it poses some problems. First
the "fly box" is reduced and as a result requires the pilot to be
extra careful maneuvering close to the terrain. Second there will be a
noticeable increase in model air speed. Third to fly nice flowing VTPR close to
the ground with minimal risk of damage to the model, the plane needs to be
designed and built lighter than normal. This introduces a "hover
affect" trait in the model in order to help the pilot fly close to the
terrain in an easier less stressful session.
Slope #3
The graphic below shows a very
stark difference to the most ideal slope #1. These slopes or cliffs are primarily
ocean coast sites where the bikinis are more attractive than this shape of
slope to try VTPR aerobatics. The lift band is very narrow and requires the
VTPR pilot to have excellent skills to keep his ship over the ground right at
or just behind the lip. Depending on conditions it may be virtually impossible
to maintain over-ground aerobatics! Only attempt this slope if you have much
experience and don't mind cracking up your model. It is possible to momentarily
perform certain maneuvers while stabbing your plane at the slope lip and flying
the plane back out into the upward lift band out front then diving back to the
ground area of the site, you might even be able to fly the plane a little behind
with momentum enough to carry the plane through a maneuver if you time it
right. It is recommended you choose a model that is very lightweight and
durable and study the possibilities very closely.
The Pilot:
This is the most enjoyable and
interesting aspect of VTPR Aerobatic slope flying. How does one get into VTPR
and why would he purposely fly his prized model in dangerous territory? In just
a few words - shear exhilaration painting
a beautiful flight! And an affinity with extreme aerobatics in general.
VTPR pilots are a very small group of fliers around the globe that have been
bitten with the desire to push a model and they're skills to the absolute limit
where few have purposely ventured. They come from all kinds of model glider
backgrounds but one thing they all have in common. The need is not only to get
the model the lowest in a very clean and controlled manner and have fun doing so.
The goal you see for a VTPR pilot is to be able to perform the most difficult
figures and maneuvers possible - but do them with ease. This takes a lot of
stick time at the slope and a lot of model and radio set up experimentation to
where the two are perfectly co-joined at the hip. It is almost as if the model
becomes ones favorite tool of the trade rather than a model. It is a lot of fun
flying VTPR but it also has a very serious attention getting persona about it
that sets VTPR pilots apart from the rest of the slope aerobatic field.
As previously mentioned there
aren't very many VTPR pilots and for good reason. I believe an asset for a new
VTPR pilot is one who has great eye-hand coordination from an early age. Maybe
one who has competed in a individual sport or one who is very proficient with
video games and the like. Ultimately, a pure love for silent flight that allows
one to express his art with a glider. All of these experiences are of great
help. On the other hand a "newbie" could come into the sport cold
turkey and with nearly no experience just may be able to hook onto the VTPR
concept and take right off. I think many of our younger generation pilots would
fare well in this sport. Whatever the case, if you are looking for the maximum
in all-around slope aerobatics, VTPR is your choice.
Good Lift...
No comments:
Post a Comment