Specifications

D.1. ELT/NAV In ter face Ca-
pa bil ity
ARTEX has en hanced 406 MHz ELT op
-
er a tion by giv ing the C406-2 the ca pa bil ity
of in ter fac ing with an air craft nav i ga tion
sys tem.
The C406-2 has the abil ity to re ceive
po si tion data (lon gi tude and lat i tude) from
the air craft’s on-board nav i ga tion sys tem.
The com mu ni ca tion pro cess be tween the
ELT and the air craft nav i ga tion sys tem is
made pos si ble by in stall ing an ARTEX
ELT to NAV (ELT/NAV) In ter face unit
(453-6500).
The In ter face unit also al lows the ELT to
be pro grammed with the air craft’s 24 bit
ad dress. When used with ELT’s that are
pro grammed for 24 bit pro to col, the In ter
-
face unit is strapped with the 24 bit ad-
dress or may be con nected to a 24 bit
ad dress switch block which is set up to
match the 24 bit ad dress par ity of the
Mode S sur veil lance and com mu ni ca tions
sys tem switch block. Note: There is no
elec tronic con nec tion be tween TCAS or
Mode S sys tems and the ELT/NAV In ter
-
face, only the ID num ber is com mon.
This fea ture was im ple mented in the
ELT/NAV In ter face unit with fleet op er a tors
in mind.
ELT’s are pro grammed with ei ther a se ri -
al ized or 24 bit pro to col. Both will in ter -
face with the ELT/NAV In ter face to
pro vide po si tion data as part of the
406.025 MHz dis tress mes sage how ever,
only ELT’s pro grammed with 24 bit pro to-
col may be used with the 24 bit ad dress
func tion of the ELT/NAV In ter face (see
Sec tion 4.3.16).
In the event of a crash, the ELT will
trans mit the con verted po si tion in for ma tion
from the nav i ga tion sys tem, such as the
GPS flight man age ment com puter, lo ran,
etc. Geo sta tion ary sat el lites con stantly
mon i tor the 406.025 MHz trans mis sions.
The crash site is in stantly known due to
the air craft’s nav i ga tion sys tem po si tion
data com mu ni ca tion with the ELT via the
In ter face unit. With out the po si tion data
be ing trans mit ted, it is nec es sary for the
po lar or bit ing sat el lites to pass over head,
us ing Dopp ler Shift tech nol ogy to de ter -
mine po si tion. In a worst case sce nario
this could be a 3 to 4 hour wait for a
po lar or bit ing sat el lite to pass over. In ad-
di tion, the ac cu racy of the po si tion fix is
much better (i.e. 100 me ters ver sus 1 to
2 ki lo me ters for the stan dard 406.025
MHz sys tem with out in ter face cou pling).
The In ter face unit sup ports ei ther ARINC
429 or RS-232 data bus for mats. An ad -
di tional fea ture of the In ter face unit is the
abil ity to au to mat i cally re pro gram the ELT
with the air craft’s 24 bit iden ti fi ca tion (long
mes sage for mat). This fa cil i tates mov ing
the ELT from one air craft to an other
when per form ing rou tine main te nance, etc.
WARNING: the ELT must be
re-registered and the prod uct la bel re
-
marked to re flect the new pro gram ming
and/or coun try of reg is try. Con tact
ARTEX for de tails of mark ing and re pro -
gram ming.
The In ter face unit will au to mat i cally re -
pro gram the ELT (if pro grammed for 24
bit pro to col), over writ ing pre vi ously stored
data ev ery time the In ter face unit de ter
-
mines from the air craft’s switch ar ray, en-
coded with the 24 bit ad dress of the
air craft, that the ELT has been re placed.
The stan dard choice of pro gram ming
which ARTEX Air craft Sup plies, Inc. pro-
vides is se ri al ized long mes sage pro to col-
col. The se ri al ized long mes sage pro to col
can be used with or with out the ELT/
NAV In ter face unit. The ELT/NAV In ter -
face unit is re quired to in ter face with the
air craft nav i ga tion sys tem and en ables the
ELT to trans mit po si tion data. The ELT
can be used with out the ELT/NAV In ter -
face unit, how ever, the se ri al ized long
mes sage will not have po si tion data in -
cluded.
ARTEX AIRCRAFT SUPPLIES DOCUMENT #570-5000
06/30/99 PAGE D-2