Specifications

the bat tery life will be short ened by ex -
ces sive ac ti va tions.
3.8. Sealing the ELT Con-
nec tor
Once all tests have sat is fac to rily been
com pleted and all har ness con nec tions
have been ver i fied to be cor rect, the con -
nec tor at the ELT end of the
ELT-to-Remote Cock pit Switch har ness
should be sealed to pre vent mois ture
from get ting into the wire en try holes.
This can be done by ap ply ing an elec -
tronic grade, non-corrosive RTV (i.e. GE
RTV 162) around the wires en ter ing the
rear of the 12-pin con nec tor 151-5012 (re -
fer to Fig ure 3-11.
En sure each of the en try holes are filled
with RTV. This will pre vent wa ter from
bead ing up and caus ing pos si ble bridg ing
be tween con nec tor pins which could re sult
in false ac ti va tion of the ELT.
3.9. He li cop ter In stal la tions
The pri mary con sid er ation to re mem ber
is that RTCA 168 (“Min i mum Per for mance
Stan dards - Emer gency Lo ca tor Trans mit
-
ters”) para graph 2.3.1 states that the pri
-
mary sen sor ( Delta V switch in the case
of the ARTEX ELTs) is in tended to re
-
spond to crash ac cel er a tions par al lel to or
co in ci den tal with the lon gi tu di nal axis of
the air craft, mov ing gen er ally in a for ward
di rec tion.
There are few guide lines, aside from ex -
pe ri ence, as to the best way to in stall an
ELT in a he li cop ter. The man u fac tur ers
have tra di tion ally ad vised in stall ing the
ELT at a 45 de gree an gle rel a tive to the
lon gi tu di nal plane of the he li cop ter. This
was as sumed to be the best mount ing
po si tion given the unique flight char ac ter -
is tics of he li cop ters.
Ex pe ri ence has shown, how ever, that
the mount ing an gle tends to preload the
G force level on the G-switch. The Delta
V switch is re quired by TSO C91a to be
far more sen si tive and ac ti vate at a sig -
nif i cantly lower sus tained G force than
older TSO C91 ELTs. ARTEX has found
that in many cases the 45 de gree mount
-
ing an gle can re sult in false ac ti va tion of
the ELT de pend ing on the type and se -
ver ity of the air craft ma neu vers. The
same can be true of abrupt take offs a nd
land ings.
While the C406-2 may be in stalled in a
he li cop ter Artex highly rec om mends use
of the C406-2HM for he li cop ter in stal la
-
tions. These ELT’s were es pe cially de
-
signed for ro tary air craft and con tain an
ad di tional five G-Switch mod ule in ad di tion
to the pri mary crash sen sor. This fea ture
al lows for six axes of cov er age.
ARTEX rec om mends that when in stall ing
a C406 se ries ELT when ever pos si ble,
the ELT should be mounted par al lel with
the floor as shown in Fig ure 3-13. If
space con straints do not per mit mount ing
the ELT par al lel with the floor, the ELT
may be tilted for ward as much as 25 de
-
grees. The di rec tion of flight ar row on the
ELT’s prod uct la bel rep re sents the di rec
-
tion in which the pri mary crash sen sor is
ori ented.
NOTE: In stal la tion in a pres sur ized air -
craft con sti tutes a ma jor mod i fi ca tion, con
-
sult the De part ment of Trans por ta tion
Re gional Of fi cer be fore pro ceed ing.
ARTEX AIRCRAFT SUPPLIES DOCUMENT #570-5000
12/10/02 PAGE 3-19