E-flite Mystique RES 2.9m ARF - Manual (Page 39)

39
minimum sink speed
In our discussion of thermals, we know sink is the
cooler air moving downward to replace the warm air
that is rising. Minimum sink speed is the speed at
which a glider loses altitude most slowly. As the term
then implies, minimum sink speed gives the glider the
maximum amount of time aloft from a given altitude. This
is the speed to fly at when you are circling in thermals,
or whenever you need the maximum lift the glider can
produce. The pitch attitude will appear to be more nose-
up.
To determine what this speed is for your model, fly it at
a slow speed, slowing down until it just stalls. Then trim
it to fly at a speed just above where it begins to stall.
Observe the pitch attitude at this speed. You will need to
practice flying at this speed without stalling so you can
come back to it whenever you want to, especially when
you are in a thermal or trying to maintain maximum lift.
maximum lift/drag (l/d) speed
This is the speed at which you can fly the maximum
distance for a given altitude. It’s used when you move
from one thermal to another, or when you need to
cover the maximum distance over ground. This will be
a moderately faster airspeed than the minimum sink
speed. You will have to experiment by starting from
the minimum sink speed and adding small amounts of
down trim to increase speed slightly. It will take practice
until you are familiar with the attitude at this speed.
Remember, you will be flying slightly faster at a lower
pitch attitude as compared to minimum sink speed.
best penetration speed
This is the speed at which the model will travel forward
against the wind or a thermal, as far and as quickly as
possible. This speed will vary with the conditions, such
as windy situations or very strong thermals. You will
want to use this speed to escape from very strong lift
(or sink). This speed has a more pronounced nose-
down appearance, which will vary with the conditions
encountered. It will also not be a consistent attitude,
but vary with the strength and direction of the lift/sink
or wind.
Once you have learned to launch and control your model
in a consistent manner, you will want to start practicing
these three speeds. Remember, these are trim speeds,
so you will be using your trim lever to obtain them. For
maximum performance, remember to use trim sparingly
and don’t depend on the stick, as you will only impart
small movements that result in drag and battery drain.
Practice smooth control inputs and use the trim lever.
This is why you trimmed the model in the test flights
and then set the mechanical linkages to reflect the trim
your trim levers back to neutral. Now you know why we
performed that procedure, to allow you to use the trim
lever for in-flight trim and have better control over flight
performance.
There are other things that can be done to bring the
performance level of your model to its absolute best.
However, they should not be attempted until you have
become proficient in the launch, control and trim of your
model.
The more you learn how to trim your model for optimum
performance, the more fun you can have chasing
thermals!
slope and alpine lift
Another form of soaring is slope lift. This lift is caused by
wind rushing over a hill, cliff or any solid land mass that
has more than 30 degrees of slope. As the air hits the
hill or slope, it will be redirected in an upward motion,
thus creating lift. The best example of this are hang
gliders that are soaring on the cliff faces. They maintain
flight by soaring on the updrafts created by the sea
breezes hitting the cliffs, which is known as slope lift.
This sort of soaring is a lot of fun, and with your model
you can always motor back to a safe landing if the lift
falls away. The important thing to understand with slope
type lift is the wind must be almost directly blowing up
the face of the hill or slope. Any more than a 20-degree
variation may cause more turbulence than actual lift.
Alpine soaring has been popular in Europe and is also
becoming popular in the U.S. Basically, it is the extreme
end of thermal soaring. As thermals develop deep on the
valley floor, they rise up the mountainside, reaching their
climax at the top of the mountain. This is often marked
by a strong breeze blowing at the top of the mountain,
which is in fact a fully-developed thermal. One of the
benefits of your model is what is called a power-assisted
sailplane. Even though it does have an electric motor
that will allow quite a steep climb, the primary purpose
of the motor is launching and returning to a safe landing
point.
Landing
Be sure to land into the wind. Due to the high-lifting
efficiency of the sailplane design, landing requires a large
area clear of trees, buildings and cars. While on your
downwind leg, remember that the sailplane glides much
better than other aircraft. You will need to set up for
landing a bit lower and with a more shallow descent than
you may be used to. As you are on approach for landing,
ensure that the model is descending slowly but also not
accelerating. If the model is accelerating, it is likely that
you will overshoot your projected target landing area.
Maintain this descent and speed, and, as the model
nears the ground (approximately 6 inches ([15cm]),
slowly apply a small amount of up elevator. The model
should level out and fly parallel to the ground, beginning
to decelerate. Be sure the model does not climb. As it
decelerates, keep flying the model parallel to the ground
until it comes to rest gently on the ground.
We hope you enjoy your model and, more importantly,
experience the art of thermal soaring. As this may be
your first thermal type sailplane, we hope this document
has given you all of the basic ingredients to enhance your
enjoyment with this wonderful product. We wish you all
the best and happy thermal hunting.
fliegen des Modells
Trimmung vor dem Flug
Wir empfehlen vor dem ersten Flug des Modells
einen Gleittest durch zuführen. Suchen Sie sich eine
ebene Fläche mit hohem weichem Gras, dass frei von
Hindernissen ist. Sie sollten die Leistung des Flugzeuges
prüfen und auch ihre als Pilot. Der Testgleitflug erlaubt
es ihnen Korrekturen an Bau- oder Steuerdefekten vor zu
nehmen, die sie vielleicht übersehen haben. Sie sollten
für die Durchführung einen Helfer haben und einen
ruhigen Tag wählen.
Tipp : Eine gute Zeit für einen Testgleitflug ist der frühe
Morgen oder die Dämmerung wenn die Luft ruhig ist.
Es ist dabei sehr wichtig sich darauf zu konzentrieren
wie sich das Modell verhält und man selber noch Zeit
hat seine Reaktionen zu überdenken. Bei den folgenden
Schritten brauchen Sie die Unterstützung eines Helfers
1. Führen Sie einen Reichweitentest durch und prüfen die
Steuerfunktionen. Stellen Sie sicher, dass die Ruder in
die richtige Richtung arbeiten.
2. Bitten Sie den Helfer das Modell unter der
Tragfläche nahe des Schwerpunktes zu halten und
vorwärts zu laufen bis die Tragfläche Auftrieb erzeugt.
Lassen Sie das Flugzeug nicht los. Prüfen Sie ob das
Modell abheben möchte. Falls nicht, geben Sie etwas
Höhenrudertrimmung und versuchen es erneut.
3. Bitten Sie den Helfer mit dem Modell jetzt etwas
schneller mit ausgerichteten Flächen und der Nase
gerade auf den Horizont gerichtet zu laufen. Spürt der
Helfer den Auftrieb wirft er das Modell.
4. Hat der Helfer das Modell losgelassen, achten Sie
bitte darauf wie es sich verhält. Ein gut getrimmtes
Flugzeug fliegt gerade auf seinem Gleitpfad und landet
sanft 15 Meter entfernt. Sollte das Modell sofort mit
der Nase nach unten gehen, ist der Schwerpunkt zu
weit hinten und das Modell ist in der Nase zu schwer.
Entfernen Sie etwas Gewicht aus der Nase. Sollte
das Modell steil nach oben fliegen und dann in den
Strömungsabriss geraten, ist das Modell zu hecklastig
und der Schwerpunkt zu weit vorne. Sie müssen etwas
Gewicht aus dem Heck nehmen oder Akku und Empfänger
weiter nach vorne bringen.
5. Giert das Flugzeug nach dem Wurf nach
links oder rechts, korrigieren Sie dieses mit der
Seitenrudertrimmung.