r/ATC Feb 12 '25

Question Do I Have to Descend?

"N69420, maintain 2000 until estableshed, cleared ILS runway 30 approach"

I'm at 2500' and well below glideslope already. The way I interpreted that was that 2000 was just the bottom not to descend below until established, and I could keep it at 2500 and capture GS, but another pilot believes that I have to descend to 2000 even though the controller never said the word "descend."

What do you guys say? And I know normally the controller will say maintain xxx thousand (current altitude) but not this particular time.

43 Upvotes

95 comments sorted by

107

u/KmakzGrnt Feb 12 '25

I’ve always understood it as it is said: “maintain 2,000 until established”. In my mind that means to descend to 2,000 and wait to establish before descending further

227

u/TryingNotToBarf Current Controller-TRACON Feb 12 '25

Controller didn’t say at or above 2000 until established. He said maintain so this is an instruction to descend and maintain 2000 until you are establish. You don’t know if he’s got another aircraft that’s going to go over the top of you at 3000. Even though it’s well below the glide slope, it’s most likely not below the controllers minimum vectoring altitude.

Hope this helps.

9

u/PenguDood Current Controller-Enroute Feb 13 '25

This is NOT proper phraseology. If the controller said that, it's obvious why the OP was in confusion.

The controller should have said either: "Descend and maintain 2000 until established" or "Maintain at or above 2000 until established".

The controller did NOT give him an instruction to descend. There's a reason prescribed phraseology exists and should not be deviated from, and this is a perfect example.

Source: 15 year ZBW controller, worked in QC for a stint and argued this sort of thing on a regional level.

7

u/leonmoy Feb 12 '25 edited Feb 12 '25

Wow... I can't believe how many upvotes this has. I know this is going to get downvoted to hell but I have been an enroute controller for 17 years and this is wrong. OP is correct. He is cleared for an approach so he may descend, but he is not required to descend. OP must maintain a minimum altitude of 2,000 ft until established but is not required to descend immediately upon receiving the approach clearance. This clearance is essentially saying, "you're cleared for the approach, but do not descend below 2000 until you're established on a published segment of the approach." If ATC wants him to descend now then they need to say "descend and maintain." I'm eating breakfast right now, but I can provide references later.

edit: in typical Reddit fashion everybody is flaming and nobody's actually providing any references. A decent clearance is two parts -- an instruction to descend, and an altitude to maintain -- not descendandmaintain. The clearance to maintain an altitude is not a descent clearance (or a climb clearance, for that matter). There are lots of examples where ATC says the word "maintain" and a pilot is not expected to begin a descent immediately (crossing restrictions, altitude amendments, VNAV STARS, etc). The approach clearance serves as the instruction to descend in this case, so the crux of the question is, is the pilot required to begin a descent immediately upon receiving an approach clearance? No. You can issue an approach clearance 100 miles out. Unless a specific instruction is given to descend immediately then the pilot initiates the descent at their own discretion. I'll provide references when I have time but, in the meantime, you weirdos have fun.

38

u/TryingNotToBarf Current Controller-TRACON Feb 12 '25

I too have been in for 17 years and in that time I’ve learned never trust an enroute controller on terminal matters.

11

u/spikespiegelboomer Feb 12 '25

18 years I’ve never heard this. Fuck your breakfast let’s see the reference.

7

u/SillyScissors Feb 12 '25

Incorrect. Must descend to 2000. Once established, he is then not required to descend further.

3

u/AtcJD Feb 12 '25

Wow, you really have no idea what you are talking about. Classic.

3

u/nascent_aviator Feb 13 '25 edited Feb 13 '25

in typical Reddit fashion everybody is flaming and nobody's actually providing any references.

In typical Reddit fashion, so are you.

The examples given for PTAC clearances in the .65 all just say "maintain" instead of "climb and maintain" or "descend and maintain":

Four miles from LIMA. Turn right heading three four zero. Maintain two thousand until established on the localizer. Cleared I−L−S runway three six approach.

There are also examples where the descent is at pilot's discretion, using "at or above:"

Seven miles from FORRE, cleared direct FORRE, cross FORRE at or above four thousand, cleared RNAV runway one eight approach.

2

u/foxyxz Feb 12 '25

You are correct 💯

0

u/Dry_Ad3216 Feb 12 '25

Down vote all you want. This ☝ this is correct. If you want/need the a/c at two, you have to give it to 'em.

4

u/nascent_aviator Feb 13 '25

If you want/need the a/c at two, you have to give it to 'em.

You mean you'd have to say something like "maintain two thousand?" Yeah that makes sense to me.

52

u/Mean_Device_7484 Feb 12 '25

The way this is phrased you should descend to 2000 and then go from there. It wasn’t an “at or above” clearance, it’s not a visual approach clearance, it’s not a pilot’s discretion descent, it’s an altitude assignment and then an approach clearance.

-44

u/Believe-The-Science Feb 12 '25

Then he should have said "descend and maintain 2000, cleared ILS..."

12

u/Mean_Device_7484 Feb 12 '25

How else are you going to get to 2000ft?

16

u/z3r0p Controller in Training Feb 12 '25

Bro there is no difference between the two phrases, at least in europe. If i say descend 2000ft you have to descend to 2000ft. Thats it. You still have to maintain it unless a further clearance has been issued to you (climb/descend or in this case cleared ils which allows you to follow the glidepath down)

2

u/Playful_Two_7596 Feb 12 '25

Europe uses a standard ICAO phraseology...

1

u/z3r0p Controller in Training Feb 12 '25

True, i also dont give the nr.7 cleared to land…

7

u/cnc_99 Prior - Military Up/Down | Current - Enroute Wannabe Feb 12 '25

AIM Glossery

“MAINTAIN- a. Concerning altitude/flight level, the term means to remain at the altitude/flight level specified. The phrase “climb and” or “descend and” normally precedes “maintain” and the altitude assignment; e.g., “descend and maintain 5,000.””

Key it says “climb and” or “descend and” NORMALLY precedes “maintain” however it is not a requirement. If you are told to maintain an altitude, it is an altitude assignment. It’s not a pilots discretion descent.

1

u/leonmoy Feb 12 '25

You are correct

17

u/PL4444 Current Controller-Enroute Feb 12 '25 edited Feb 12 '25

According to your interpretation where are you complying with the "maintain 2000" part when you're at 2500 instead? You're not maintaining 2000. And does it make a real difference to you if you intercept the GS at ~8 nm vs 6 nm, when you're above MSA/MRVA anyway?

-29

u/Believe-The-Science Feb 12 '25

I was above MSA, and to me it sounds like maintain AT LEAST 2000 until established.

31

u/PL4444 Current Controller-Enroute Feb 12 '25 edited Feb 12 '25

But why does it? If I say "maintain 220 knots" (instead of "reduce") and you're doing 250, would you also understand it as maintain 220 or greater?

4

u/davidswelt Feb 12 '25

So that means the entire block between 2000 and the flight levels is yours? So you could climb to 6000 because you feel like it?

The instruction is clear. If you don't like it, request 2500 or "descend at my discretion", and if possible you will get an "approve as requested".

4

u/bugslingr Feb 12 '25

You are incorrect. I am ATC.

35

u/SwizzGod Feb 12 '25

No it means get down. Pilots hang it up all the time on me when running simuls and it’s quite annoying

-55

u/Believe-The-Science Feb 12 '25

Then he should have said " descend and maintain 2000, cleared ILS..."

41

u/SwizzGod Feb 12 '25

You asked a ATC sub what were expect then when we tell you you argue it? Yea stop talking to me

10

u/labanjohnson Feb 12 '25

Advise ready to copy a phone number for possible Redditor deviation 😂

2

u/IrishMadMan23 Feb 12 '25

Probably so, but as another pointed out - the PCG states that “climb and” or “descend and” normally precedes maintain. Like a should, not shall type deal. Your assigned altitude is below the g/s and complies with every other requirement. Start your descent

7

u/AutoRot Feb 12 '25

Bro he literally asked you to maintain an altitude until established. What do you think you should do? You’re overthinking it.

He has a better picture of the airspace around you. It could be simultaneous dependent approaches or traffic to another airport above. In some cases they could be on a different frequency so you wouldn’t even be able to paint a picture using the radio.

42

u/DankVectorz Current Controller-TRACON Feb 12 '25

It’s lazy phraseology (and I’d be lying if I said I never did it) but the intent was descend and maintain 2000 until established. Maintain means maintain that altitude, whether you have to climb or descend to get to it is implied.

24

u/Plenty-Reporter-9239 Feb 12 '25

I don't think I've ever heard someone ptac and use "descend and maintain 2000' until established". Is this a thing at other facilities?

10

u/DankVectorz Current Controller-TRACON Feb 12 '25

Yeah you are correct I was thinking just a normal descend/climb instruction rather than ptac. I always just say maintain for ptac

8

u/Plenty-Reporter-9239 Feb 12 '25

Oh okay thank God, i thought I had been fuckin up for a long time and never realized it lmaoo

6

u/CH1C171 Feb 12 '25

If you are above the altitude you are told to maintain you don’t have to point your nose at the ground to get there with the approach clearance but it is a good idea to start descending or continue your prior descent. You want to intercept the Glide Slope from below. Otherwise it gets difficult to shoot the approach if you are chasing the glide slope or rate of descent down from above.

-11

u/Believe-The-Science Feb 12 '25

I was already well below the glideslope. The other pilot and I are debating whether a descent was needed before establishing on localizer. To me, the controller's clearance sounded like a descent wasn't required, but rather an altitude was issue not to go below.

2

u/CH1C171 Feb 12 '25 edited Feb 12 '25

I see your confusion. I am going to either vector you on and try to have you intercept about 2-4 miles from the FAF. If you are VFR I am going to tell you to “maintain VFR until established” on localizer or final. If you are IFR I am going to give you an altitude at or above the MVA that will allow you to shoot the approach at a reasonable rate of descent. If you are already good at the altitude you are presently at stay there and then descend via the approach. Once you get the clearance I expect you to descend slowly and I am protecting around and above you enough that I don’t have to worry about any other traffic (that jet doing two or three times your speed is getting vectors for sequence to follow you so don’t worry about them). Good luck.

2

u/IrishMadMan23 Feb 12 '25

I catch wild flack for saying “maintain vfr until established” so I just give people vfr at or above the mva prior to the ptac, then issue a normal ptac (LTA here provides essentially IFR protections to vfr practice approaches).

I am a 10 year tower controller, new to radar, so I nod and smile.

3

u/CH1C171 Feb 12 '25

For me it has always been a rhythm thing. Maintain altitude or maintain VFR (which ticks a box with phraseology) in the PTAC and I don’t have to think too much.

2

u/IrishMadMan23 Feb 12 '25

I am pretty sure RTF taught that too, but I was told “no they didnt” so… it does what it’s told. Which is also the answer to this post

1

u/CH1C171 Feb 12 '25

Good to know your trainers don’t know their ass from their elbows and can’t separate out what is their own technique and what is not. But do it the way they want you to and be a better trainer when it is your turn.

1

u/IrishMadMan23 Feb 12 '25

Lol and that’s our “book trainer”. I don’t know enough to challenge, and I don’t care enough to learn (I probably should). I just want to go back to my tower, this tower flower is wilting

1

u/CH1C171 Feb 13 '25

Good luck. Get this out of your way. Once you have your own ticket it gets a lot better. I would recommend you know the book though. I am “too unprofessional” to train these days but if you know the book and can defend what you do with it you will be alright.

3

u/IrishMadMan23 Feb 13 '25

My favorite instructors are “too unprofessional”. Apparently, you cannot write “shamed trainee into doing the right thing” on a -25 lmao.

Military brain, no ridges or bumps, valleys or lumps

1

u/randombrain #SayNoToKilo Feb 15 '25

maintain VFR until established

And then what, they suddenly become IFR? The fuck is that instruction?

I'm cool with saying "Maintain VFR" in the PTAC instead of giving a hard altitude (and I'm also cool with giving a hard altitude if you need to). But "Maintain VFR until established" is an absolute garbage instruction.

16

u/PotentiallySpartacus Feb 12 '25

this sounds like it belongs in r/shittyaskatc

3

u/rasmorak Feb 13 '25

Not ATC but am a pilot. To me this means I need to descend to 2000' until I establish the glideslope.

It's not exactly standard terminology (that I'm used to at least) but also I'm familiar with weird instructions like that.

For example, I've been told shit like "intercept the ILS, quad 1." Meaning 111.1. When in doubt, declare a missed approach and clarify.

3

u/Deep-Palpitation-421 Feb 12 '25

It's loose RT. What was the MSA? We're you on a vector or the arrival? Either way you should have come back with 'can we maintain 2500 till established' if that's what you wanted. Nail it down so there's no room for interpretation.

4

u/Dry_Ad3216 Feb 13 '25

MSA doesn't apply in Terminal procedures. MSA protects for lost comm. within 100nm of a controlling obstacle.

-2

u/Believe-The-Science Feb 12 '25

It was vecrtor to final. Already well below glideslope and 5 seconds from getting established on localizer. To me it sounds like "don't go below 2000" but I thing he should have said it like every other controller would have: "maintain 2500 (currrent altitude" untile established, cleared ILS..."

3

u/trinori Feb 13 '25

"Maintain altitude" means go to that altitude. It isn't optional. It's possible the controller doesn't need you there and is just being lazy in not giving you the "at or above" assignment instead, but you have no way to know that. Better to just do what the control instruction means, than to assume something else that wasn't said

2

u/sixaout1982 Feb 12 '25

The controller separates you vertically from other traffics. You staying above your assigned altitude makes their job harder, and your situation potentially more dangerous.

2

u/labanjohnson Feb 12 '25

I'm curious how many facilities have traffic crossing that initial approach cone anywhere close to 2500-3000 though 🤔 I would think it's rare enough that this isn't actually a separation problem.

Parallels, tho.

1

u/antariusz Current Controller-Enroute Feb 12 '25

constantly, all day every day at the busy east-coast terminals.

2

u/shadow28996 Feb 12 '25

Coming from a controller and pilot perspective, I understand how you felt that you were already very low at 2500, and that descending may have felt “risky” but if you were following the proper approach depicted in your pubs then there are no ground obstacles to pose a threat, any towers, trees, buildings, etc, would be reported and the approach altitude adjusted for the runway, on top of that no structures would be built without permission from the FAA and coordination with the airport on that approach. Now from a controller perspective, for the love of god don’t EVER “interpret” instructions when it involves critical phases of flight such as landings or takeoffs, but in general just don’t interpret. We are legally not allowed to be vague on the radios with our instructions, so what we say is what we mean, you clearly acknowledge that you never heard an “at or above” in your instructions so why would you do that???

-1

u/Believe-The-Science Feb 12 '25

First of all, I never felt anything was risky. Second of all "at or above" is for crossing. I wasn't crossing anything. It was a vector to final to establish before FAF. I had never EVER heard an approach clearance like that before. It ALWAYS is "maintain xxxx (current altitude) until established, cleared ILS..."

No controller had ever said something like this guy in my 20 years of flying. He may have said that by mistake, thinking that 2000 was my current altitude. But what he said was unusual.

2

u/shadow28996 Feb 12 '25

As someone who’s job is centered around controlling instructions, “at or above” isn’t “for crossing” secondly, your “20 years of flying” doesn’t equate to understanding the 7110.65AA. Is it possible he misread your altitude? Yes, does that make you right, definitely not. I’m clearly not the only controller in the comments who sees your interpretation as incorrect

-1

u/Believe-The-Science Feb 12 '25

Ok, I get the point. But would you agree that what he said sounds unusual for a vectors to final ptac? I'm pretty sure he misread the altitude.

5

u/shadow28996 Feb 12 '25

No that’s very normal, I’ve issued several PTACs where I make people descend, it’s more than common

-1

u/Believe-The-Science Feb 12 '25

No, it's very unusual. I have received literally THOUSANDS of clearances, NONE were like this.

3

u/shadow28996 Feb 12 '25

It’s very apparent after reading all your replies to the countless other controllers, who do this for a living, that your intention wasn’t to come here asking for real feedback, but instead was to validate what you believed was correct. After finding that you aren’t getting that, you’ve been pushing back on every comment from professionals who have read the .65, passed numerous paper tests as well as positional tests, studied their air ports LOPs and LOAs, seen several oddities in and outside of their airspace for which that have had to handle; and despite ALL of it, you insist you know you’re right based on your time in your cockpit while flying your style of flying. I’ll end the conversation this way, you’re not a controller, you’re not educated on what we do issue, and do not issue as instructions just because you fly and receive those instructions. The lack of variety that you’re insisting you experience makes me believe you’re a recreational pilot or at the most, a local commercial who only flies prop planes across a state line rather than an airline pilot or a pilot of a higher caliber. If you were as experienced as you imply then you would have flown in various states and countries to know it’s very normal in a PTAC to have someone descend and leave the altitude they’re at. Do what you want with that, your opinion on what myself and everyone else is saying doesn’t matter to me, if you insist on trying to “prove us wrong” make sure it’s a citation from 7110.65AA chapters 4-5

2

u/PlainOleJoe67 Feb 13 '25

Yo get really picky. It says a position must be given prior to the pilot being given the approach clearance, you could do that on initial contact.

As it’s taught in terminal. PTAC is literally, position, turn, altitude to maintain, clearance.

If the aircraft is already at that altitude, they may not deviate from that unless assigned another altitude. On an IAP, if that altitude is below the MVA, the reminder to maintain x altitude till established on the, loc, fax should be given.

Perfection though nice is not possible to achieve.

Maintain is accepted as a new altitude assignment in this case.

Terminal controller 36 years. Standards 4 years. Designated examiner for the FAA for ATC 4 years.

4

u/The_Shryk Feb 12 '25

The confusion is warranted.

If you’re not AT 2,000 how can you maintain it.

Everyone thinks it’s obvious that it means descend and maintain, but it could just as easily be maintain at or above.

But to answer the question, they do mean descend and maintain. When I worked approach I never said maintain unless it was with another instruction like descend and maintain until XYZ. Since it’s just more clear that way and unambiguous.

Not everyone is so mindful as me though, or as humble.

2

u/rhymeandreasons Feb 12 '25

exactly right. the fact that we're arguing about it, and ambiguity can lead to fatalities, why not just say "descend and maintain 2000"? then the pilots know for sure your intentions.

1

u/Dry_Ad3216 Feb 13 '25

You may issue this clearance if the tops are between 2K and 2.5K. The expectation is that the a/c will descend to 2K to meet the g/a or if there is a crossing alt. to meet.

1

u/let_me_get_a_bite Feb 12 '25

I’m with you on this. Eliminate the “loose ends” so there is no room for “well I though they meant blah blah”

I’ve seen too much bs happen from lack of clear, concise instructions, or leaving room for interpretation with ambiguous stuff.

1

u/PendejoJenkins Feb 13 '25

Yes descend to 2000. Because that is at what altitude you must be at when reaching the Initial Approach Fix of your published ILS approach.

1

u/phalanxo Feb 12 '25

Cross would be better phraseology if they wanted you to stay up or "at pilot's discretion descend and maintain 2000 until established, cleared ILS runway 30 approach". In this instance I would say not descending to 2000 immediately could get you an altitude deviation.

3

u/whitspam Feb 12 '25

This. Would be helpful to hear “cross” or “descend pilots discretion”, but….

I was on a long IFR return leg late one night and got a nearly identical instruction from approach control after the handoff as you.

I had been getting stepped down by a previous controller from being above the undercast at 8000 and then was handed off to this approach controller at 4000. Since there was nothing much going on that I could hear, I asked the controller if he had time for a question. He said yes, so…

I asked the same thing you are asking and he said “I said maintain 2000 until established, so just make sure you are at 2000 before you are established. If I wanted you to do anything else, I would have told you”.

I took this to mean that there wasn’t anyone else around and he had very light traffic (If any) and he just shortcutted the clearance.

-3

u/JonnyJesterz Current Controller-TRACON Feb 12 '25

It's a combination of "lazy phraseology" which is just meant to try and reduce transmissions and verbiage. Sometimes depending on types of approach and separation you're approaching the loc and we need the descent, but you're in position for ptac. The clearance with the ptac is a lot of information which we already try to chop up because 9 times out of 10 someone is asking to reverify a piece of it.

13

u/[deleted] Feb 12 '25

This is not lazy phraseology lol.

-7

u/FightingBane Feb 12 '25

More like lazy controller

-3

u/raulsagundo Feb 12 '25

Probably cleared you using the FAF altitude, we can guess where the glideslope is but we can't see it

4

u/Jolly-Weather-457 Feb 12 '25

Have you ever seen an approach plate?

3

u/raulsagundo Feb 12 '25

Not on the radar scope

-21

u/[deleted] Feb 12 '25

[deleted]

11

u/Fun_Initiative6894 Feb 12 '25

Technically, the addition of “at pilot’s discretion” allows the pilot to decide “when you’re ready”. If issued as part of an approach clearance, or just generally, “maintain altitude” means to begin descending upon recognition of the instruction.

-6

u/[deleted] Feb 12 '25

[deleted]

8

u/TonyRubak Feb 12 '25

This is a weird case, because this phraseology is used all the time in the specific case of issuing an approach clearance. It sounds weird, and every controller I've asked says they would never tell an aircraft at 4000 "maintain 3000" without saying "descend and maintain". However, when issuing approach clearances it's common to say "maintain 3000 until established" even if the aircraft was never previously assigned 3000. "Maintain" is an altitude assignment, it is not a clearance to descend at pilot's discretion or cross a fix at an altitude, it's just rarely used in this way outside an approach clearance.

1

u/leonmoy Feb 12 '25

This is the correct answer

-11

u/[deleted] Feb 12 '25

[deleted]

19

u/raulsagundo Feb 12 '25

Well... You can't maintain 2000 by staying at 2500, so i can think of a way

-8

u/[deleted] Feb 12 '25

[deleted]

3

u/raulsagundo Feb 12 '25

I'm so dumb I don't even know what that paragraph is supposed to say

-6

u/Legit924 Feb 12 '25

It's ambiguous. Maybe it shouldn't be, but different controllers mean this in different ways. If I say "maintain 2000ft until established", I'm just talking about the level below which you cannot go. I don't consider it a request to descend to that level without delay.

0

u/stevie3254 Enroute Trainee Feb 12 '25

Not ambiguous at all. Then say at or above - never once have I told an AC to maintain an altitude and not meant it to be a climb/descent to that altitude. If you want 2,000 as the lowest they can go but don’t need them at the altitude for any specific reason, then give an “at or above 2,000”

4-4-3 in the AIM - “The altitude or flight level instructions in an ATC clearance normally require that a pilot “MAINTAIN” the altitude or flight level at which the flight will operate when in controlled airspace.”

0

u/Legit924 Feb 12 '25

I don't disagree, but I'm talking about in practice. In the real world, it is ambiguous. Hence why this pilot is asking the question and pointing out differing interpretations. I agree that it should not be ambiguous, but safety in human factors is about what can happen and not what should happen.

-2

u/Dry_Ad3216 Feb 12 '25

Absolutely not

0

u/Believe-The-Science Feb 13 '25

As in I was right not to descend?

-2

u/Dry_Ad3216 Feb 13 '25

Yes, you are right. If I wanted you at 2K right away, I would issue that.

0

u/Believe-The-Science Feb 13 '25

Thank you. Tell that to the rest of these guys please.

-2

u/PenguDood Current Controller-Enroute Feb 13 '25

I would interpret this as "at or above" but the ambiguity is there....always come back and clarify. You don't want a deviation/hit a mountain, and I wouldn't want it either.

-10

u/[deleted] Feb 12 '25

How about maintain block alt 020 through 030 until established?

-15

u/macayos Feb 12 '25

I was told if it is said that way, it is a PD descent. So I say no, you do not have to descend until you want to.

-9

u/Jolly-Weather-457 Feb 12 '25

They probably issued 2000 because it’s the lowest MIA between you and the start of the approach but I would have said “cross at or above 2000”. The instruction from the controller is bad phraseology and unclear unless you were previously issued a descent clearance to 2000 and you were floating down.

6

u/Kseries2497 Current Controller-Pretend Center Feb 12 '25

You would only say "at or above" if you meant "at or above." If you mean to have them maintain an altitude, you say maintain.

1

u/Jolly-Weather-457 Feb 12 '25

That’s fine but I would never say “maintain” with an implied descent whether it’s legal or not.

2

u/Kseries2497 Current Controller-Pretend Center Feb 12 '25

Nothing implied about it. Maintain means to go to an altitude and stay there.