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
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