I came across this from a pilot...

 

I think it right to say most airlines now do as follows:
In the climb, when cleared to a flight level, set standard immediately, whatever the transition altitude. Standby altimeter remains on QNH until passing Climb MSA.
In descent, whenever cleared to an altitude, set QNH immediately, whatever transition level. Standby altimeter set to QNH before descent commences.

The problem with lower transition altitudes and a low cleared flight level is if you have a low pressure area and wait for transition to change to standard, you may instantly exceed your cleared flight level. Rates of climb are so high now that great care has to be taken.

 

 

Now i always thought you set STD and QNH at the TA and TL ? Seems like you can do it alot sooner and earlier in both phases of flight? Also what about STBY ALT anyone have any idea on how to best use these, i've been reading pilots leave it on QNH all the time and some change it at TEN CHECKS. Looking for good RW pilot experience or anyone with good knowledge on this. Thanks

In the US the altimeter is set to standard at transition altitude (18000ft). Check out this video series, it's very good and pretty sure they were changing to STD at transition altitude as well both on the way up and on the way down...

 

Oh well, once again I can't seem to paste anything into a post on this forum. But it's the KLM 737-800 videos posted about here in the NGX forum

 

Dave

Altimeters must be set to airfield QNH for takeoff. When cleared to

climb above transition altitude, and the aircraft is above 3000 feet

AGL, both pilots will set their altimeters to Standard. The standby

altimeter is set to Standard when climbing through MSA. The PF will

lead all altimeter changes by calling “SET QNH ___/STD.”

 

 

On receiving clearance to descend to an altitude, both pilots will set

QNH. Caution must be exercised should an intermediate leveloff above

transition level be issued by ATC in which case STD must be

re-selected.

 

 

Seems like you can change it before

It's all technique.  As long as you comply with your clearance you can do it whatever way you want.  I typically reset the altimeter climbing through 17,000 and descending through FL 190 ( assuming TA is FL180 in the states), but that's just me.  Just use common sense.

will this not affect AC seperation doing it earlier than the TA - TL ? And what about alt busts?

will this not affect AC seperation doing it earlier than the TA - TL ? And what about alt busts?

 

Not really. As long as you're in the FLs, you need to be on STD. If you're in the alts, you need local (by controller direction, not just some random AWOS you picked up).

 

In the States, we adjust the lowest usable Flight Level based on the pressure in that area. 29.92 or greater means lowest usable is FL180. If it's below 29.92, the lowest usable climbs up.

 

I explain it briefly in one of my videos.

 

 

 

As far as procedure goes, if I'm relatively sure I won't get an amended altitude before I get into the FLs (after being cleared up in the FLs), I'll immediately set STD.

 

Example:

I'm climbing up to 16,000 and get cleared to FL220 - STD.

I'm climbing up to 12,000 and get cleared to FL220 in busy airspace - I'll hold off until about 17,000.

 

It's all dependent on the situation, though.

will this not affect AC seperation doing it earlier than the TA - TL ? And what about alt busts?

 

It would only be an issue if you were given an amended clearance that required you to level off prior to the TA/TL, in which case you would simply reset your altimeter accordingly.

Certain clearances should act as triggers that raise flags in your mind and remind you that you need to do something.  A clearance above/below 18,000 and above/below 10,000 are two examples.  If I am level at 10,000 and cleared to FL240 a flag is raised that I will need to reset my altimeter.  I may not need to do it at that exact moment but at some point in the climb I will.  The time to think about it is leaving 10,000, not as you are blasting through 18,000.  Descending through 10,000 is another example.  If I'm level at 16,000 and cleared to descend to 4,000 that clearance triggers a flag that I will need to slow below 250.  Again, the time to start thinking about your speed reduction is when you leave 16,000, not blasting through 9,000 realizing you are still doing 300 knots.  Keep your mind ahead of the airplane.

 

I would teach this method to new-hires transitioning to jets for the first time and most found it helpful.  Remember the saying "Don't ever let an airplane take you someplace where your brain hasn't arrived at least a couple of minutes earlier."

It's all dependent on the situation, though.

I may have asked this question before. If I did, I don't remember the answer. PANC ANC6 SID indicates maintain FL200 or altitude assigned by ATC. If ATC assigns no altitude, you are cleared to FL200. TA is 18000. The altimeter could be set to STD on the runway since you are cleared to a FL. No, Yes, Something else? The same would apply to KDEN and KLAS where SIDS clear you into the flight levels.

I may have asked this question before. If I did, I don't remember the answer. PANC ANC6 SID indicates maintain FL200 or altitude assigned by ATC. If ATC assigns no altitude, you are cleared to FL200. TA is 18000. The altimeter could be set to STD on the runway since you are cleared to a FL. No, Yes, Something else? The same would apply to KDEN and KLAS where SIDS clear you into the flight levels.

See my answer above.

 

 

Honestly, in the situation where they gave you "climb via the SID," and there's still 18000' of possibility that they could say "amend your altitude to _____" (where ___ is an altitude lower than the top altitude), I'd hold off until about 16-17.

I'd hold off until about 16-17

Thanks. That's what I have been doing.

Why not just do it at the TA TL? It's still one button push. Too early can be as bad as too late.

 

My technique is handfly to 18,000, then its STD, BARO reset and CMD B. Boom boom boom. 1 2 3.

Example:

I'm climbing up to 16,000 and get cleared to FL220 - STD.

I'm climbing up to 12,000 and get cleared to FL220 in busy airspace - I'll hold off until about 17,000.

 

Thanks kyle. So if i'm in a busy TMA i'll have to be extra vigilant and reset according to the TA and TL.

Why not just do it at the TA TL? It's still one button push. Too early can be as bad as too late.

 

My technique is handfly to 18,000, then its STD, BARO reset and CMD B. Boom boom boom. 1 2 3.

 

Thats what i've been doing matt, setting it at the TA TL. But came across that when reading my FCOM

It would only be an issue if you were given an amended clearance that required you to level off prior to the TA/TL, in which case you would simply reset your altimeter accordingly.

 

Yeh makes sense thats also stated in my FCOM. Cheers

In the SOPs that I'm familiar with: set STD on main (PFD) altimeters when cleared to a FL and above acceleration altitude. The standby gets set to standard once above TA and MSA.

 

On the way down: set the standby to airfield QNH before TOD as part of the descent preparation, then set airfield QNH on the primaries once cleared to an altitude.

 

 

My technique is handfly to 18,000, then its STD, BARO reset and CMD B. Boom boom boom. 1 2 3.

 

Nice. Might have to use that.