Flying With Ballast - Multiplex SCHAMPUS Bauanleitung

extensions off and you have a faster and more man@uvE-
ble model which can manage a€robatics without any diffi-
culty. You will find it highly interesting to compare the
model's performance and handling with and without the ex-
tensions, and to decide when to use them to suit the flying
conditions and the task in hand.
Flying with ballast
Two ballast chambers are incorporated into the wings,
which will accommodate two lead rods, Order No. 71 2760,
for a total weight incr€as€ of about 500 grams. The basic
result of adding ballast is to increase the model's cruising
speed. This gives a better glide angle, but at the expense
of a slightly higher rate of sink. In practic€ this means: fly
with baltast in strong winds and for distance and spe€d fly-
ing. Fly without ballast in calm weather, when the wind is
light at the slope, and wh6n thermal activity is light or
non-existenl.
The options of ballast and wingtip odensions allow a wide
range of possible combinations, which you can use to
fine-tune the model to match the actual weather conditions
and the type of flying called for on the day.
Flat field flying
*.;lying from a flat field site eliminates the risk of down-
draught which is inherent to slope flying, and in that re-
spect it is relatively safe. However, making the best use of
flat field lhermals is not particularly easy, and calls for con-
siderable skill and experience. Areas of rising air are harder
to detect and recognise at a flat field, because they tend to
occur at higher altitude than at the hillside, where it is often
possible to find lift while the model is cruising along the
edge of the slope, and then circle away in it. A thermal at a
flat field which occurs directly overhead is very hard to
recognise, and to exploit it to the full requires a highly
skilled pilot. For this reason it is always besl lo go thermal
seeking off to one side of wher€ you are standing. You will
recognise thermal contact by the model's behaviour. Good
thermals are obvious, because the model will climb
strongly, but weak thermals take a practis€d eye to detect,
and you will need a lot of skill to make use of them. With a
little practice you will be able to recognise likely trigger
points for thermals in the local landscape. The ground
warms up in the sun's heat, but heat absorption varies ak-
'ording to the type of tenain. The air over the warmer
r€found becomes warmer in tum, and the mass of walm air
flows along close to the ground, driven by the breeze. Any
obstruction - a shrub or tree, a fence, the edge of a wood,
a hill, a passing carJ even your own model on the landing
approach - may cause this warm air to leave the ground
and rise. lmagine a drop of water on the ceiling, wandering
around aimlessly, and initially staying stuck to the ceiling. lf
it strikes an obstruction it will fall down. A triggercd thermal
can be thought of as the opposite of the drop ot water. The
most obvious thermal triggers include sharply defined snow
fields on mountain slopes. The air above the snow field is
cooled, and flows downhill; at the edge of the snow field,
part- way down the valley, the cool air meets warm air
flowing gently uphill, and pushes it up and away as if cut
otf by a knife. The result is an elitremely powerful but
bumpy thermal bubble. Your task is to locate the rising
warm air and centre your model in it. You will ne€d to con-
trol the model constantly to keep it centred, as you can ex-
pect the most rapid climb rate in the core of the thermal.
Once again, this technique does demand some skill. To
avoid losing sight of the model, be sure to leave the ther-
mal in good time. Bear in mind that the model is always
easier to see under a cloud than against a clear blue sl{y. lf
the model g6ts too high, extend th€ aiörakes, apply slight
down elevator, and fly continuous circles to lose height
quickly and safely, Set up your landing approach with
plenty of height in hand, and open the airbrakes on the final
approach so that the model is close to the ground for the
minimum period of time. The "regulation" square ap-
proach, consisting of straight downwind run away from the
pilot, crosswind leg, and a straight final approach with
brakes out and flare at the last moment is the safest oossi-
bl6 for the model, the pilot and for any onlookers. In many
competitions, padicularly duration and spot landing events,
this form of landing approach is obligatory in any case.
Slope soaring
Ridg€ soaring is an extremely attractive form of model fly-
ing. To fly for hours on end in slope lift, independent of any
launching aid, is one of the mosl uplifting of experiences,
The crowning glory must surely be thermal flying from the
slope: launch the model, fly out over the valley, seek your
thermal, find it, circle up to the limits of vision, bring the
model down again in an exciting series of aerobatic ma-
noeuvres, then begin the game all over again - that's model
llying to perfection. But take care - there are dangers fo.
your model lurking at the slope. Firstly, in most cases land-
ing is much more diflicult than at a flat field site. lt is usu-
ally necessary to land in the lee of the hill where the air is
turbulent; this calls for con@ntration and a high-speed ap-
proach with last-minute aiörake extension. A landing on
the slope face, i.e. right in the slopo lift, is even more diffi-
cult. Here the trick is to approach downwind, up the slop€,
and flare at exac-tly the right moment, iust before
touch-down. Another danger is that the slope lift or thermal
may disappear at the most unhelpful moment, at which
time you are fac€d with a high-risk man@uvre: länding out
in the valley below. However, you can reduce the risk by
selecting a likely landing site in the valley before you even
launch, in case you have no option later on. You could
even go and investigate the chosen field, so thal you can
woft out the best approach, avoid any obstacl€s, and find
out what the local wind conditions are like. lf an outlanding
is inevitable, fly to the chosen landing site and carry out a
disciplined approach as at a flat field site: a short, straight
final approach with airbrakes odended. As far as possible
keep the model in your line of sight with the chos€n landing
area, as this should avoid undershooting, and so give you a
better chance of actually making it to your chosen site. lf
the sun is shining you will be able to judge the model's altF
tude with some accuracy by the glider's shadow, whictl will
appear when the model is faidy low. With a sharply defined
shadow it is even possible to carry out accurate spot land-
ings down in the valley. Oon't give up! Thermals can ap-
pear even at quite low altitudes. However, once you have
initiated the final approach you should continue with the
landing ev€n if a patch of lift comes along, since by then it
is no longer safe to try and circle in a thermal. Take your
time, locate the landing site carefully, and aim the model
deliberately for it. Try and keep in mind any obvious land-
marks which you can use later in case the model proves
difficult to locate. lf the model lands in a field of standing
com, only let one person go to look for the model. He
should walk carefully and by the most direct route to the
model, and leave the field again by the same route. Other-
wise you may be held liable for any damage to the crop,
and - worse still - you may los€ the right to fly at the site. lf
the model is visible from the launcfi site, a fellow modeller
at the top of the hill may be able to direct you straight to it
once you have reached the area. Your colleague holds a
model fuselage up in the air, and you walk in the direciion
indicated.
"Nose
down" means
'bloser
to me",
"nose
up"
means
"away
from me". lt is possible to dircct somebody
with great accuracy by this simple method. However, the
main thing to remember when seeking a thermal with the
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