Originally Posted by
Just This Once...
RVSM compliance et al - if you are shepherding an airliner or just intercepting one it is best if you don't break the congested & carefully choreographed airspace by introducing a non-compliant aircraft to the mix.
As for 1435 Flt they were not Tranche 1 jets in my time, even from the start of the transition from F3. It could have happened since of course but it was never the plan.
They were originally Tranche 2s, and they were still Tranche 2s in 2014, but they've been Tranche 1s for some time.
Are the Tranche 1s NOT RVSM compliant?