landing headlights
parts list
2x LED ultra bright, color at wish,
with narrow beam angle.
2x pre-resistor for 5V
1x SMD-Subminiature-power-switch 191779 from C.
price 12,95 EUR (01.01.2004)
The Supply is
drawn directly from the reciever.
Doing so, one should watch, that the additional 50mA can be supplied by the
BEC.
The pre-resistor calculates:
Rpre = (5V - U_break) / I_rated
whereat:
U_break = break-through voltage of the LED (datasheet) in [V]
I_rated = the optimum current of the LED (datasheet) in [A]
Proposals for LEDs:
 |
185004, yellow 5mm, 3600mcd, 8°, 1,00 EUR (Ud = 2,2V, If 20mA) |
|
184990, orange 5mm, 3600mcd, 8°, 1,00 EUR (Ud = 2,2V, If 20mA) |
 |
153745, white 5mm, 6400mcd, 20°, 5,09 EUR |
|
153908, white 5 mm, 9200mcd, 20°, 5,95 EUR |
|
153855, white 5 mm, 3000mcd, 22°, 4,06 EUR (Ud = 3,8V, If 20mA) |
The smaller
the beam angle, the better the visibility over long distances gets.
|
|
The LES are to be installed somewehre
in the wing, preferably not too close to each other.
I chose the servo-covers (Robbe) of the Selection for
it.
Right before the servo linkage there is just enough room to glue the LED into
the covering.
Exact alignment is important, as the LEDs do have a narrow beam cone.
If the alignment is bad, you will see lit one LED after the other.
At a good alignment it can also be seen, whether the nose goes up or down.
The effect is especially great,
if you have to land in front of a dark background (wood) and it begins to
dawn.
Normally the airplane then is nearly invisible, and re-appears only if the
landing grass comes into the background.
All collegues have already landed, because they fear the dawn.
connector add-on