Verifying mode C question

[BigBoeing]

MATS 1 states "A mode C readout can be assumed to have been verified if it is associated with a deemed validated Mode A code"

Is this referring to when an aircraft is transferred from one controller to another, i.e they know it will have been identified so can assume that the mode C is correct as well? Are there any other situations in which this applies

Cheers

[pushapproved]

The mode A and C should be validated and verified respectively by the first radar controller after departure. It generally follows that it can be assumed to be correct for the next sector unless told otherwise!

[eastern wiseguy]

Unless you are the controlling authority in Scotland.......then you do it again.

[ADIS5000]

BB

Yep, it also applies when separating aircraft. For instance, under a RAS if conflicting traffic is squawking a Mode A that is deemed validated (ie assigned by a unit capable of validating it (usually means the unit is radar equipped)) then to avoid that traffic you only need take 3,000ft vertically as the mode C is deemed verified. But if the Mode C of the conflicting traffic was not deemed verified, (ie 7000 squawk) then you need the 3000ft but also cannot merge with the 7000 squawk.

Regards,

ADIS

[Cuddles]

OK then, what about level assessment and separation using mode C? 1 a/c climbing, 1 a/c descending through each others level, when are they vertically separated? 1000 ft apart on the C or 1800 ft apart on the C, or something else.....?

[atcomarkingtime]

.......and Cuddles...what if they were 35 miles apart!!!!!!:mad:

[Bern Oulli]

CUDDLES. In the UK, without the pilot reporting a level vacated, 1,800 feet on the Mode C. e.g. Aircraft A is climbing passing FL104 (has left FL100), and aircraft B has descended through FL86 (has left FL90), they are vertically separated.