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RMC
25th Aug 2019, 14:51
Hope someone can help.

having spent my entire life on short haul I now find myself operating into the USA.

In the UK we select transition Alt/ fl as soon as we are cleared to it (deviation from EU rules).

my company says we still set as we are cleared (as long as there are no planned FL restrictions) so I could be cleared for a STAR just after TOD and select QNH as soon as the cruise FL is vacated.

interested in what you guys do as if you set within 1,000’ of Transition (which is what we used to do) then we will be descending on a different altimeter setting above transition level?

Thanks in advance

misd-agin
25th Aug 2019, 15:24
Nope. We reset approaching 18,000' or descending through FL190 (+/-). At FL390 and cleared to descend via a STAR that has 5000' as the bottom altitude? We don't reset the altimeter at FL390. We do it approaching FL180. Occasionally you get told to level off. That is exactly what happened when we were on a STAR descending to 15,000' with lots of deviations about weather. In the mid 20's we were told to maintain FL230. Later we were given a heading due to other aircraft deviating on climb out and descending.

RMC
25th Aug 2019, 16:05
Nope. We reset approaching 18,000' or descending through FL190 (+/-). At FL390 and cleared to descend via a STAR that has 5000' as the bottom altitude? We don't reset the altimeter at FL390. We do it approaching FL180. Occasionally you get told to level off. That is exactly what happened when we were on a STAR descending to 15,000' with lots of deviations about weather. In the mid 20's we were told to maintain FL230. Later we were given a heading due to other aircraft deviating on climb out and descending.

Thanks! This is what I was worried about......if this is the way most operate in the USA then we need to go back to our original SOP which was to select inside 1,000’ of transition....otherwise when these unexpected level offs happen we would be on different altimeter settings to the rest of the continent. Could do with a few more replies and will write to the high paid help.

Sunrig
25th Aug 2019, 19:24
Yes, switch at 18.000 ft, not earlier... Be aware they sometimes give you the local area altimeter setting which is necessarily not the same as your destination airports one.

MarkerInbound
25th Aug 2019, 21:02
Also a below FL190 transitioner. It happens often enough as pointed out above that ATC's plans change.

zondaracer
25th Aug 2019, 22:19
If your arrival has altitude constraints above 18,000, and you transition the altimeter setting before reaching the transition level, you could miss some flight level constraints by a few hundred feet potentially.

RMC
27th Aug 2019, 18:04
Agreed Zondaracer.....my company tries to cover that by using ICAO PANS OPS procedures
“my company says we still set as we are cleared (as long as there are no planned FL restrictions) so I could be cleared for a STAR just after TOD and select QNH as soon as the cruise FL is vacated.”
.....but I still don’t like the fact that it seems every US carriers SOPs are to set close to transition. I have had far more early level offs in US airspace than anywhere else in the world and don’t think we should be doing something different from those who spend most of their time in US airspace. When in Rome....

zondaracer
27th Aug 2019, 20:36
At my last company, I flew a rudimentary jet that wouldn’t let me preset the altimeter setting, so we were allowed to set the center standby altimeter to the local altimeter setting once we were cleared to descend below transition level, but the two main altimeters would remain at standard until passing the transition level.

In my new jet, we can preset the altimeter setting but we definitely leave it in standard until passing transition.

neilki
19th Sep 2019, 13:00
Thanks! This is what I was worried about......if this is the way most operate in the USA then we need to go back to our original SOP which was to select inside 1,000’ of transition....otherwise when these unexpected level offs happen we would be on different altimeter settings to the rest of the continent. Could do with a few more replies and will write to the high paid help.
Its called TRANSITION for. reason. FL180 down and 18.,000 climbing. As published on your Jepps and documented in the AIM. RVSM airspace is not the place to be inventing procedures.....

RMC
14th Nov 2019, 15:25
Nelki please can you give me the AIM reference for this as we have a standardisation issue which needs resolving