Carl Pattinson wrote:
> Hi Folks,
> As the day of our first flight draws nearer (permit to test applied for), we
> have been having some thoughts about the possibility of landing gear up.
> OK so it shouldnt happen but everybody knows that if it can, then it will.
> We now of at least one Europa owner who lost his prop because he forgot to
> lower the undercariage and we are sure there are many more who kept quiet
> (lets face it its not something one admits to !).
> Anyway whether it is a real risk or not we thought it might be a good idea
> to build in some added insurance and wondered if anybody else has been there
> before.
> A recent trip to Maplins came up with a nifty door alarm which costs a mere
> 5.00 and activates an ear shattering scream (110db) when the magnet is
> moved away from the alarm box (about the size of a packet of cigarettes). If
> the idea works we may remove the reed switch out of the box to save space
> (and move the box to somewhere out of the way). Incidentally the power
> supply is 2 AAA batteries.
> Our simple solution was to attach the magnet to the gear retraction arm (on
> top of the armrest/ wheelwell next to the locking latch) with the alarm unit
> resting beside it and then wire in a microswitch so that the alarm is
> powered up when the throttle lever is closed (or partially closed - some
> trial and error required here)
> If the throttle is closed and the gear is not locked down the alarm will
> sound (there is also a flasher). Sounds simple, so where's the catch.
> If anyone has a better idea please let us know.
> Carl Pattinson
> G-LABS
Hi Carl,
The alarm is a great idea but it may give you false security. I am not sure that
it will protect you from a scenario where the arm is in position and the small
latch is not and my understanding is that at least one accident has occurred
when the arm has jumped out of the detent from the shock of landing. I think it
is wise to pay particular attention to :-
1. Ensuring that the undercarriage arm is spring loaded so that it falls into
and remains in the DOWN detent and requires a positive side force to move it
out.
2. Ensuring that the small mechanical latch (LG12A) is completely free on its
pivot and falls into place without any assistance.
3. If you have upholstered your plane,or intend to, ensure that upholstery
material does not interfere with the arm or the latch or your ability to easily
check the latch.
Please forgive me for being pedantic, but I believe that experience has shown
that small mistakes or oversights in this area can be unforgiving. I would like
to wish you a trouble free first flight and many smooth landings.
Cheers, John
N262WF, mono XS, 912S
Mooresville, North Carolina
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