Specifications

•
“The mounts shall have max i mum
static lo cal de flec tion no greater than
2.5 mm(0.1in) when a force of 450
newtons (100lbs) is ap plied to the
mount in the most flex i ble di rec tion. De
-
flec tion mea sure ments shall be made
with ref er ence to an other part of the air -
frame not less than 0.3 me ters (1 foot)
nor more than 1.0 me ters (3 feet) from
the mount ing lo ca tion.”
• In ad di tion, RTCA Doc u ment Num ber
DO-182 rec om mends that “all ELT sys -
tem com po nents which must sur vive a
crash in tact, ....should be at tached to
the air frame in such a man ner that the
at tach ment sys tem can sup port a 100g
load...in the plus and mi nus di rec tions of
the three prin ci pal axes of the air craft.”
• Fur ther in stal la tion guid ance can be
found in FAA Ad vi sory Cir cu lar
43.13-2A (Ac cept able Methods, Tech
-
niques and Prac tices - Air craft Al ter
-
ations). Chap ter 2, para graph 28 deals
spe cif i cally with Emer gency Trans mit ter
in stal la tions.
Mount the ELT unit hor i zon tally so that
the ri gid ity re quire ments are met and the
ar row on the mount ing tray is aligned
within 10 de grees of the lon gi tu di nal axis
of the air craft and pointed in the di rec tion
of flight. Re fer to page 3-19 & Fig ure
3-13 for he li cop ter in stal la tions.
Finally, in se lect ing a lo ca tion for the
ELT in stal la tion, the fol low ing cau tionary
ad vice should be taken into con sid er ation:
3.2. An tenna Mount ing Lo
-
ca tions
Lo cate a po si tion where the an tenna
can be in stalled VER TI CALLY (up to 15°
off the ver ti cal plane is ac cept able) with
at least 30 inches clear ance from other
an ten nas (es pe cially VHF) mounted on
the air craft.
The coax ca ble should not cross any
pro duc tion breaks (ma jor struc tural sec
-
tions) in the air craft so that in the event
of a crash the ELT and the an tenna are
in same air craft sec tion. This usu ally re -
quires plac ing the an tenna di rectly above
the ELT unit. Do not bun dle the ELT an
-
tenna coax with any other VHF ra dio
coax, power har ness or the ELT re mote
switch har ness.
If the ELT trans mit ter and ex ter nal an
-
tenna are on op po site sides of an air -
frame pro duc tion break, the com po nents
should be se cured to each other by a
tether which can sup port a 100 G load
(ELT weight x 100). The in ter con nect ing
an tenna-to-ELT coax ca ble should have
suf fi cient slack on both ends that it will
not be sub jected to any ten sile load and
should be tied loosely to the tether.
Use only the ARTEX ap proved an ten -
nas. The ELT will not op er ate prop erly
with out be ing con nected to the an tenna
for which it was de signed.
ARTEX AIRCRAFT SUPPLIES DOCUMENT #570-5000
04/04/02 PAGE 3-9
CAUTION:
Avoid locating the ELT where it will be subjected
to unprotected exposure to harsh chemical
fluids such as deicing compounds. They can
promote cracking and fracturing of the ELT
mounting frame and housing components by
degrading and weakening the structural integrity
of the housing and tray material. These same
chemical agents can also cause corrosion on
electrical connections.