Collision Avoidance Systems

jcarlyle wrote:
Last week, before the Minden midair, I reviewed Collision Avoidance

Zaon MRX - This was the one I bought. Pros - shows threat distance
and height; receives civilian signals A, C, S and 3/A, as well as
military signals X, Y and 2 (snip)

WTF are military signals X and Y? Military uses IFF modes 1, 2, 3
(same as civilian mode A or 3/A), C (same as civilian mode C - gives
altitude only), 4 (secure), and S. I'm hoping "X" and "Y" are modes 1
and 4, since most military traffic have those on all the time-
especially mode 4.

Neat device, though, and definitely on my xmas list!

Kirk
66

Kirk, will a TPAS which can only receive mode A,C, and S will detect
any military aircraft?

kirk.stant wrote:
jcarlyle wrote:
Last week, before the Minden midair, I reviewed Collision Avoidance

Zaon MRX - This was the one I bought. Pros - shows threat distance
and height; receives civilian signals A, C, S and 3/A, as well as
military signals X, Y and 2 (snip)

WTF are military signals X and Y? Military uses IFF modes 1, 2, 3
(same as civilian mode A or 3/A), C (same as civilian mode C - gives
altitude only), 4 (secure), and S. I'm hoping "X" and "Y" are modes 1
and 4, since most military traffic have those on all the time-
especially mode 4.

Neat device, though, and definitely on my xmas list!

Kirk
66

Ramy wrote:
Kirk, will a TPAS which can only receive mode A,C, and S will detect
any military aircraft?


Ramy,

In peacetime all military flights (caveat - my experience is AF, Navy
and Army may be different) are on IFR flightplans, so will be squawking
Mode 3/C (same as mode A/C). During certain phases of flight, they may
cancel and go VFR, but will still be squawking mode 3C/1200, just like
everyone else. Some newer jets may have mode S installed (C-17? F-22?)
in which case that would be on also.

It's possible during training in restricted airspace that mode 3 (and
S) may be turned off (so the other guy can't find you with his onboard
interrogator) but there shouldn't be any civilian traffic in that
airspace.

Other military modes (1, 2, and 4) are used as tactics and conditions
require, but are not required. More than likely they would be on
during routine flight to and from bombing ranges and restricted
airspace, and while using MOAs, so that other military planes equipped
with IFF interrogators can see and identify them.

Short answer - yes!

Hope this helps,

Kirk
66

I bought a Zaon MRX earlier this year and I have been very pleased. It
is a small, passive system that only requires me to turn it on before
flight and turn it off after the flight is over. I bought it at Wings
and Wheels for approx $ 500.00 and I do feel that it a very valuable
safety device that folks should really consider purchasing, especially
for those operating in areas with a fair amount of commercial jet
and/or general aviation traffic. I operate out of Moriarty, NM (30 NM
East of Albuquerque, NM) and we have a fair amount of jet traffic
descending toward the Albuquerque International Sunport or climbing out
on departure. The MRX has really worked very well alerting me to
aircraft that get within 5 NM and 5,000 feet! - 3R