Maintain altitude until glide slope intercept or step down?

bLizZuE

Calling for engine starts en français
This discussion has been coming up between me and captains I have been flying with recently.

Intermediate altitude for the ILS is 3000(glide slope intercept altitude), current altitude is 5000. Clearance as follows:

"Fly heading XXX, maintain 3000 until established, cleared ILS runway XX"

Do you descend to 3000 once established on a published segment of the approach? (The way I taught instrument students, the way I interpret the clearance, the way I feel is right)
Do you join the glide slope from 5000 and follow it down to DA? (I hear arguments for this technique as: avoid wake turbulence and passenger comfort with a constant descent)

I have been flying in different bases this month and it appears there are different interpretations of what 'established' means. Some guys in one base say do it one way, the others say do it this way. I just want to do it the right way.

The first time I attempted to fly to the intermediate altitude it was with a check airman and he yelled at me. Threatened my job and insulted me in ways no way associated with my flying. Lately I just get puzzled looks.

So what say you?
 
Re: Maintain altitude until glide slope intercept or step do

The way I fly it and the way my 135 company trains us to fly it is the way you describe. Once on a published portion of the approach and cleared for the approach we descend using the step downs published until glide slope intercept, then follow the glide slope to DH. Our POI and check airman will bust you on your checkride if you hold altitude till intercept for a constant descent.
 
Re: Maintain altitude until glide slope intercept or step do

I would fly the heading, descend to any intermediate crossing altitudes, (fly the stepdown,) until reaching 3000, and then maintain that until GS intercept. Any CA yell at me for it, I'd reference them to the appropriate section of our FOM.
 
Re: Maintain altitude until glide slope intercept or step do

I have been flying in different bases this month and it appears there are different interpretations of what 'established' means. Some guys in one base say do it one way, the others say do it this way. I just want to do it the right way.

Ah the joys of "personal technique".

Welcome to the world of flying with a person for one leg, and you have to make it work. I'd say a bigger challenge than this specific issue is developing techniques to deal with this for the rest of your career, no matter what seat you sit in.

Personally, I'd descend at a slow rate to intercept the glideslope and manage the speed. If there are stepdowns, respect those to the FAF. Done.
 
Re: Maintain altitude until glide slope intercept or step do

As with all things in aviation, it depends. The biggest thing to keep in the back of your mind is, staying hight and intercepting the glideslope may not, in most cases will not, guarantee that you will meet any crossing restrictions, ie, the glideslope is a fixed plane while step down fixes are a barometric plane that can change from day to day. ATC could very well be expecting you to be at a barometric altitude at some fix for traffic and if you just follow the glideslope you may be too high or low.

As for busting, sounds BS. Most altitudes on an approach are MINIMUM altitudes, very few have mandatory altitudes. The easiest way to solve all of this, "ABC Approach N69YM is going to stay at 5000 until glideslope intercept."
 
Re: Maintain altitude until glide slope intercept or step do

The way I fly it and the way my 135 company trains us to fly it is the way you describe. Once on a published portion of the approach and cleared for the approach we descend using the step downs published until glide slope intercept, then follow the glide slope to DH. Our POI and check airman will bust you on your checkride if you hold altitude till intercept for a constant descent.

I am going to call BS on your POI and your company's check airmen on that...If you recall most of the time when you are given a vector to join the localizer of a precision approach you are given a MINIMUM altitude to maintain until established before commencing your descent...NEVER heard of what you talking about from any 121/135 pilot or an FAA inspector. Unless you hear the words..."descend and maintain" in a clearance, altitude is at your discretion on a precision approach once the approach clearance has been issued.
 
Re: Maintain altitude until glide slope intercept or step do

Were these issues happening in Chicago?
 
Re: Maintain altitude until glide slope intercept or step do

I am going to call BS on your POI and your company's check airmen on that...If you recall most of the time when you are given a vector to join the localizer of a precision approach you are given a MINIMUM altitude to maintain until established before commencing your descent...NEVER heard of what you talking about from any 121/135 pilot or an FAA inspector. Unless you hear the words..."descend and maintain" in a clearance, altitude is at your discretion on a precision approach once the approach clearance has been issued.

This.
 
Re: Maintain altitude until glide slope intercept or step do

I may be stepping out of my bounds here...

If I recall, there are actually 2 "glide slopes" on an ILS. One is correct, and the other is much higher (altitude) signal and requires a steeper descent to the runway. Based on that, and me being me, I'd rather step down and intercept at the appropriate, i.e. published, intercept altitude. I worry that I might intercept the false glide slope from the higher altitude.
 
Re: Maintain altitude until glide slope intercept or step do

I may be stepping out of my bounds here...

If I recall, there are actually 2 "glide slopes" on an ILS. One is correct, and the other is much higher (altitude) signal and requires a steeper descent to the runway. Based on that, and me being me, I'd rather step down and intercept at the appropriate, i.e. published, intercept altitude. I worry that I might intercept the false glide slope from the higher altitude.


It is pretty simple to tell if you are on the wrong glideslope with DME/crossing radials.

I agree with BE19 I'd intercept at 5k. Probably saves a little gas too. I do remember reading something fairly recently warning pilots of busting step down fixes while following the glideslope on hot/high pressure days. So I guess there's that to consider as well for blizzue's version.
 
Re: Maintain altitude until glide slope intercept or step do


We're sort of talking about two different scenarios. If you're at 5000 and the published GS intercept altitude is 3000 with no intermediate stepdowns, there's nothing wrong with intercepting the glideslope and following it down (it's impossible to bust stepdown altitudes when there are none) unless your company prohibits it.

ORD has had many issues with the exact problem your link addresses because they have multiple parallel approaches with multiple stepdowns (I think for separation purposes). Capturing the glideslope beyond stepdown fixes and following it down can definitely get you in trouble, but there's nothing wrong with it if you monitor carefully to make sure you make the crossings. Just hitting "appr" outside of stepdowns and relaxing is what gets you into trouble.
 
Re: Maintain altitude until glide slope intercept or step do

"Fly heading XXX, maintain 3000 until established, cleared ILS runway XX"

Go down to 3,000, get established on the loc and intercept the glideslope....staying at 5,000 ft is not an option

if they say (which they often do)

"Fly heading XXX, maintain 3000 or above until established, cleared ILS runway XX"

then do whatever you want, but in all cases as mentioned above whatever your doing and wherever you are don't let the GS take you below the stepdowns (only happens in a few places)..18C in CVG around ANTRI comes to mind
 
Re: Maintain altitude until glide slope intercept or step do

"Fly heading XXX, maintain 3000 until established, cleared ILS runway XX"

vs

"Fly heading XXX, maintain 3000 or above until established, cleared ILS runway XX"

That makes complete sense. However what if the clearance is

"Fly heading XXX, maintain 3000 until FIXNAME, cleared ILS Runway XX"

I (and most people I fly with) read that as a limit on descent, not an instruction to vacate your present altitude and as long as following the glideslope down won't put me below 3000 outside of XXXXX then I'll do it.

That said, this has become an issue in Charlotte recently because they are giving this clearance but expecting aircraft to start down right away. When they are running three parallel approaches they want guys to join at different altitude along the approach for each runway just in case somebody blows through the localizer on the join. I've heard several people get yelled at by approach because they didn't start down right away and waited for the GS to come in. That's NOT what the clearance says, but approach was expecting it.
 
Re: Maintain altitude until glide slope intercept or step do

"Fly heading XXX, maintain 3000 until established, cleared ILS runway XX"

Go down to 3,000, get established on the loc and intercept the glideslope....staying at 5,000 ft is not an option

if they say (which they often do)

"Fly heading XXX, maintain 3000 or above until established, cleared ILS runway XX"

then do whatever you want, but in all cases as mentioned above whatever your doing and wherever you are don't let the GS take you below the stepdowns (only happens in a few places)..18C in CVG around ANTRI comes to mind

This is correct. You can't just maintain 5000' and follow the GS down. Descend now to 3000' and then intercept the LOC and GS at 3000'

Now if ATC had said, "fly heading XXX, maintain 5000' until established, cleared ILS approach." Stay at 5000' until intercepting the LOC, and then technically you should be decsending via the step downs until the minimum GS intercept altitude. There could be a note on your chart that you can intercept at the higher altitude, in which case, just stay at 5000'.

All this got me confused because for years at my old airline we would always maintain the altitude that ATC assigned, and intercept the GS from there for every single ILS approach we did with every single captain I flew with.

THEN I start at a new airline, flying the same equipment, and my IOE checkman tells me I've been doing it wrong the whole time, because I wasn't doing any of the step downs. Wow. Think how hard it was to undo 4 years of shooting ILS's and not doing the step downs, to having checkairmen asking me why I'm not doing the step downs. I guess to me it doesn't seem as safe doing multiple step downs, but after reading that InFO, that's the proper way to do things.
 
Re: Maintain altitude until glide slope intercept or step do

"Fly heading XXX, maintain 3000 until established, cleared ILS runway XX"

Go down to 3,000, get established on the loc and intercept the glideslope....staying at 5,000 ft is not an option

if they say (which they often do)

"Fly heading XXX, maintain 3000 or above until established, cleared ILS runway XX"

then do whatever you want, but in all cases as mentioned above whatever your doing and wherever you are don't let the GS take you below the stepdowns (only happens in a few places)..18C in CVG around ANTRI comes to mind

Thank god someone out there knows how to fly. The clearance was maintain. Thats not an option. In many cases you will get a maintain 3 till established, cleared for the approach and the FAF is at 2700 or something other than what you were given to maintain. Thats when you go to 3, get established and then at your discretion(as long as your position on the approach allows) descend further if you want to. But that first "maintain" is a direction to follow. it would be like approach saying fly heading 190 and maintain 3 thousand and you doing neither because you thought you could do it better on your own. Both are clearances.
 
Re: Maintain altitude until glide slope intercept or step do

It is absolutely an instruction to vacate your present altitude, whether you are established on the loc on a published segment of not... You better start down to 3,000 ft.... That IS what the clearance they gave you says, and that's why approach started yelling in CLT... "maintain 3,000 til established".... That means they want you to maintain 3,000 ft until you get established on the loc.... So get on down there, what are you waiting for? By staying at 5,000 you are deviating from an ATC clearance ! Is it so much effort to scroll to 3,000 ft in the altitude select knob? Take every clearance literally!
 
Re: Maintain altitude until glide slope intercept or step do

It is absolutely an instruction to vacate your present altitude, whether you are established on the loc on a published segment of not... You better start down to 3,000 ft.... That IS what the clearance they gave you says, and that's why approach started yelling in CLT... "maintain 3,000 til established".... That means they want you to maintain 3,000 ft until you get established on the loc.... So get on down there, what are you waiting for? By staying at 5,000 you are deviating from an ATC clearance ! Is it so much effort to scroll to 3,000 ft in the altitude select knob? Take every clearance literally!

I actually phrased that wrong. My fault.

The clearances they have been giving are "cross FIXNAME at 3000, cleared for the ILS whatever".

You are right, with what I originally said you do have to descend right away, but with the cross XXX at XXX there is no requirement to vacate an altitude as long as you cross the fix at the cleared altitude.
 
Re: Maintain altitude until glide slope intercept or step do

If that's the case then absolutely, u can stay high as long as you want...... However being based CLT, your original scenario is more likely, hence why people are getting yelled at there
 
Re: Maintain altitude until glide slope intercept or step do

It is absolutely an instruction to vacate your present altitude, whether you are established on the loc on a published segment of not... You better start down to 3,000 ft.... That IS what the clearance they gave you says, and that's why approach started yelling in CLT... "maintain 3,000 til established".... That means they want you to maintain 3,000 ft until you get established on the loc.... So get on down there, what are you waiting for? By staying at 5,000 you are deviating from an ATC clearance ! Is it so much effort to scroll to 3,000 ft in the altitude select knob? Take every clearance literally!

Just asked a buddy that works a low sector at Miami center and he confirmed this.
 
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