Levelling off above ATC cleared altitude on approach
 

There has been some discussion at my place of work about the legality of levelling off for deceleration and configuring above your ATC cleared altitude. Eg you are cleared to 2500’/ cleared for the approach, but the FMS has a level decel at 3000’.

Can you fly the descent managed, levelling at 3000’ until approach slope intercept (normally 3 deg)!or must you force the aircraft down to the cleared altitude and intercept approach slope from there?

It is a bit pedantic in my opinion, but if anyone has any references it would be greatly appreciated.

Surely unless the approach procedure is prescriptive or when a CDA is required, I would say you can fly it how you like. ATC will always tell you if they want you to reach the platform by a certain point/distance etc. Plus some RNAV procedures are designed and coded as you describe...

Depends on the exact wording that's used, I'd imagine.

I'll probably be shot down for being too simple....but isn't it as simple as the minimum rate of climb or descent in controlled airspace is 500fpm except for the purpose of acceleration or deceleration?

No it isn't.

Why do your colleagues need to decelerate so aggressively? If it is required, unless issued a minimum RoD then I can't see any issue. On our A320s, when selecting Flaps 2 you might get upto 800fpm climb as the flap comes out (poor FMGC logic), nobody ever seems to complain.

Common sense?

Levelling off at 5450ft in the vicinity of the airport to comply with a speed request is unlikely to make you friends with ATC. On the approach? Independent parallel approaches use different platform heights for obvious reasons so I'd be inclined to stick to it like glue to ensure separation.

On the other hand, if I'm already level at 3000ft on the localiser, decelerating nicely, and ATC offer a further descent to 2500ft and further with the ILS my inclination would be to remain level and intercept the glideslope from 3000ft in the spirit of our CDFA policy. Others might pay lip service and start a 200fpm descent towards 2500ft.

Depends where You are, and often the answer will be found in the AIP Enroute section 1. As an example, for the UK :

3.2.2.4.1 In order to ensure that controllers can accurately predict flight profiles to maintain standard vertical separation between aircraft,
pilots of aircraft commencing a climb or descent in accordance with an ATC Clearance should inform the controller if they anticipate that their rate of climb or descent during the level change will be less than 500 ft per minute, or if at any time during such a climb or descent their vertical speed is, in fact, less than 500 ft per minute.

The above is complemented by the rules of CDO below 6000 ft where applicable.

First of all the "descent clearance" is not a clearance, it is an instruction and you have to obey. However, the approach clearance is in fact a clearance and you can execute it in a manner that fits your needs. You have every right to act as you desire unless you are regulated by ATC with IAS or VS, or unless it is specified otherwise in the AIP (Jepp, Navtech, Lido or whatever you have in the cockpit)

AUStronauts at work again ggrowler, a firm grasp of the non essential.

For a laid back country, we sure are uptight, too many bush lawyers.

I'm pretty relaxed about all things, and at this phase of flight i believe it's more important to fly the profile that will get you where you want to be, company speed restrictions, configuration recommendations etc, than worry about these little issues. You're 10 miles from touchdown, it's going to make tenth fifths of f*@# all difference to the traffic pattern.

That's en route not approach.

The 500fpm minimum (in the UK) is only a requirement above the transition altitude and in a hold.

My bad, I did not quote the entire paragraph.

what's the problem descending to ATC cleared altitude. Radar vector ATC ensures terrain clearence. Can you not be cleared for approach below or above level off altitude?

Depends on where. Last time I was in South America, just this situation arose. "Unable"

Is 500 fpm (with speed brakes of you're real close) not enough?

1000 fpm in France.....

And yes, you can configure, slow down, whatever. BUT - you need to descent to 2500ft eventually EXCEPT they tell you it is "pilots discretion", then it is, quiet logic, up to you. Not really rocket science....