What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

ATC Says, ?Altitude Upon Request.? Say what?

ArVeeNiner

Well Known Member
So I?ve been using VFR Flight Following more now than any other time in my many years of flying. I try to use it on any trip outside my local area and it?s really been great. ATC is very accommodating and the more I use it the less chance of my stumbling over my words and sounding like the rookie that I am.

So a couple of weeks ago I was on a flight from the SF Bay Area to the Sierra foothills. During my initial call to ATC they asked what altitude I was requesting. I told them 5,500 feet. They told me to fly at or below 5,000 feet and they added something like ?5,500 feet upon request.? I hadn?t heard that terminology before.

So I do understand holding me at 5,000 because there were a couple of jets flying overhead for landing at Oakland. So, I waited several minutes until the jet traffic seemed to subside a bit before calling back and asking if I could to go 5,500 feet. This was approved and off I went.

I figure basically he?s saying ?yea man, chill at this altitude for a while even though it?s not where you want to be at. At some point hit me up later if you still want to go higher and I?ll check and see if it?s cool or not.? (The controller is from California too.) I?m pretty sure this is what is going on here. If so, I?m thinking I did the right thing by waiting to ask for higher later. I was perfectly fine flying at 5,000 the entire way but that?s not a proper VFR cruising altitude.

My questions are:

1-What exactly does this phraseology mean?

2-Would it have been ok just to stay at 5,000 feet and not request higher? I think being at the proper VFR altitude is safer of course.
 
More likely "Altitude ON request".

Like you guessed... He's putting you on hold, but has the note to get back to you when able.

And yes... You could have gone to 5,000 ft, as he cleared you "at or below 5,000". However, nothing wrong with sticking to the VFR 500ft.
 
He/She has acknowledged your cruising altitude request, and intends to delete your restriction when he is sure you won’t cause any trouble for him.
 
...?yea man, chill at this altitude for a while even though it?s not where you want to be at. At some point hit me up later if you still want to go higher and I?ll check and see if it?s cool or not.?
You crack me up, dude! Did he harsh your mellow?
 
So, when I hear that, I should wait until they tell me to go higher eventually? To me, the terminology suggests that they are waiting on me to request higher at a later time.
 
If you are on Facebook, there is a really good group called Ask a Pilot/Air Traffic Controller that I’ve found to be a very helpful resource. You will get a comprehensive answer there if you ask.
 
Last edited:
So, when I hear that, I should wait until they tell me to go higher eventually? To me, the terminology suggests that they are waiting on me to request higher at a later time.

Basically, yes to the first question. He?s telling you that he has heard your request and is putting that in to the system and his own thinking. If you need to climb and he hasn?t responded with a clearance higher, then ask again. Otherwise, he?s basically telling you he knows you want to go higher, and he has the request in his queue.
 
VFR flight following is dual benefit service. ATC will often provide requests of you to help them manage traffic separation. Once they are talking to you, you are part of their active traffic to manage, unlike VFR traffic they are not talking to. They will give you altitudes or vectors to manage separation with other IFR/VFR traffic that they are managing. For the most part, they only operate on IFR altitudes, so any altitude requests they make will be in 1000's and not 500's.

We should understand that ATC and pilot are helping one another when under flight following and we should strive to accomodate their requests. Given that compliance with your request is not an obligation, we should strive to be good "partners" and accomodate any requests.

Don't forget that when they (approach or center) give you an altitude or vector, they are used to full compliance (they spend 95% or more of their time dealing with IFR traffic), so don't deviate without telling them you are doing so. Even though you are VFR, you are not allowed to ignore an instruction from ATC. No different than a tower controller at a D airport. You can reply unable, but can't ignore it.

The "5500 upon request" is his way of saying that eventhough he gave you 5000, he will accept a request from you to fly at 5500. Usually if he can't give it to you now, he will indicate that in the statement. It is easier for them to manage everyone on IFR altitudes to maintain separation and that is likely why he gave you 5000 instead of 5500. Separation requirements are mostly in 1000' increments and everyone else he is managing are on 1000' levels.

You usually only see this in busy approach control areas. It would be rare with center or less busy approach controllers.
 
Last edited:
They will give you altitudes or vectors to manage separation with other IFR/VFR traffic that they are managing.

They *MAY* give you those instructions.

Probably been beaten to death, but bears repeating...VFR Flight Following is provided on an "as available" basis (I think those are the right words). ATC is not required to provide you with point-outs to all other traffic, or even conflicting traffic, if they're busy. Their job is to provide IFR-IFR separation.

They generally will, but it's the PIC's responsibility in VFR conditions to *see and avoid*.
 
They *MAY* give you those instructions.

Probably been beaten to death, but bears repeating...VFR Flight Following is provided on an "as available" basis (I think those are the right words). ATC is not required to provide you with point-outs to all other traffic, or even conflicting traffic, if they're busy. Their job is to provide IFR-IFR separation.

They generally will, but it's the PIC's responsibility in VFR conditions to *see and avoid*.

Good point and agreed. Wasn't implying that they will always provide separation. Only trying to explain why the instructions were given to the OP in his situation.
 
Given what the FAR's say, I would interpret your original ATC instruction as "authorization" :)

? 91.159 VFR cruising altitude or flight level.
Except while holding in a holding pattern of 2 minutes or less, or while turning, each person operating an aircraft under VFR in level cruising flight more than 3,000 feet above the surface shall maintain the appropriate altitude or flight level prescribed below, unless otherwise authorized by ATC:

(a) When operating below 18,000 feet MSL and -

(1) On a magnetic course of zero degrees through 179 degrees, any odd thousand foot MSL altitude + 500 feet (such as 3,500, 5,500, or 7,500); or

(2) On a magnetic course of 180 degrees through 359 degrees, any even thousand foot MSL altitude + 500 feet (such as 4,500, 6,500, or 8,500).

(b) When operating above 18,000 feet MSL, maintain the altitude or flight level assigned by ATC.
 
The ?on request? phraseology is frequently misunderstood. ATC is not asking you to request it again. It means they are passing on your request to someone else, probably whoever controls the higher airspace.
We get this a lot at LVK, when calling up for an ifr clearance. LVK ground replies, ?Clearance on request?. It means that they need to call someone else (phone or computer) to get your clearance; they?ll let you know when they have it. You sometimes hear grumbling or laughter from the tower when the pilot replies to the ?on request? transmission with, ?well, I want it now?.
Now, these behind the scenes communications often go quickly, so, in the OP?s case, it?s likely the controller had just finished the needed coordination when the OP called back.
 
They *MAY* give you those instructions.

Probably been beaten to death, but bears repeating...VFR Flight Following is provided on an "as available" basis (I think those are the right words). ATC is not required to provide you with point-outs to all other traffic, or even conflicting traffic, if they're busy. Their job is to provide IFR-IFR separation.

They generally will, but it's the PIC's responsibility in VFR conditions to *see and avoid*.

Even then don't count on it. I came face to face with a glider pilot while I was on climbout from a class C airport IFR in VMC. I saw a gray dot off in the distance, squinted for a second, and before I knew it I was looking at some dude's face about 200 feet below me. I "politely" asked ATC if he saw what I was seeing, he seemed sorta puzzled for a second, THEN decided to give me a traffic advisory and asked for an estimate of the glider's altitude.
 
Even then don't count on it. I came face to face with a glider pilot while I was on climbout from a class C airport IFR in VMC. I saw a gray dot off in the distance, squinted for a second, and before I knew it I was looking at some dude's face about 200 feet below me. I "politely" asked ATC if he saw what I was seeing, he seemed sorta puzzled for a second, THEN decided to give me a traffic advisory and asked for an estimate of the glider's altitude.

The glider might not have Mode C altitude reporting, and may not have even had a transponder and was showing up a non-transponder target on ATC radar.

I'm guessing you were outside the actual Class C airspace.
 
The glider might not have Mode C altitude reporting, and may not have even had a transponder and was showing up a non-transponder target on ATC radar.

I'm guessing you were outside the actual Class C airspace.

On the periphery of it. He saw it on radar. No idea of its capabilities. I would've thought some sort of advisory would've been apropos given our proximity. Either way, one should not extend the assumptions about traffic separation to IFR. However it came to pass I was face to face with another aircraft while on an IFR flight so watch out!
 
ATC

As a retired air traffic controller (LA Center), a 40+ year pilot, and active commercial pilot, most of the comments are on the money.

You were instructed to remain at/or below 5k (probably due to a conflict) so he is providing separation -- from other traffic or airspace -- and by his stating "On request" -- he is letting you know he now has your request for your cruising altitude, and -- traffic permitting -- he will let you know when it is safely available. Usually he will make note of your request, but he may get busy and not get back to you for a while (or could forget). There is more going on then what you hear -- landline calls, interfacility coordination, computer entries, etc. If he keeps you on an assigned code, he is responsible to provide service, but you are his lowest priority. If he feels that he can't provide appropriate service and safety, he should terminate you and put you back on a 1200 code, but often it is less workload for him to keep you on his frequency if the airspace is busy, and you are in conflict with other aircraft (you are more predictable that way). But always, maintain your scan, looking for other traffic. In the case of the glider conflict, ATC radar is not optimized for non-transponder traffic, and something as slow moving as a glider does not always get the controllers attention. I've seen semi truck traffic on busy highways that show up better.

Howard Long
CFII, ATP, retired controller
 
As a retired air traffic controller (LA Center), a 40+ year pilot, and active commercial pilot, most of the comments are on the money.

...... In the case of the glider conflict, ATC radar is not optimized for non-transponder traffic, and something as slow moving as a glider does not always get the controllers attention. I've seen semi truck traffic on busy highways that show up better.

Howard Long
CFII, ATP, retired controller

And I have called LA Center to report several VFR gliders - including me - over Wrightwood at 17,500 ft in wave lift.

With no transponders and zero ground speed I'm sure they couldn't see us on radar - I got no response on the radio...

I simply reported our position to FSS who did answer. :)
 
ZLA

Howard, I was just going to post but you beat me to it! Do you know Freeman, or Sensback? I work at ZMA.

Slow moving targets do not always show up due to a equipment filter....Moving Target Indicator.

ARTCC radar is piped in from up to 5 radar sources along with ADSB, primary radar(raw radar echos) and secondary radar(Beacon). Which is much different than approach.

If I am too busy, sector down the crapper, then I may terminate VFR's as I know they may not get the level of service they deserve due to higher priorities...IFR's.

I will vector VFR's and cap their altitudes to keep them safe. After all our primary focus is separating aircraft and issuing safety alerts... Having a VFR in an arrival corridor to a major airport is not safe by any means.
 
Yup.

The ?on request? phraseology is frequently misunderstood. ATC is not asking you to request it again. It means they are passing on your request to someone else, probably whoever controls the higher airspace.

+1.

And "on request" is generally better news than "take it up with the next controller." :)
 
Glad gliders were mentioned

First, to the point of this thread, I was one of the dummies on one of my early solos in power that requested clearance to depart, and the tower replied: "On request". I waited a few minutes, and eventually repeated myself. Again, he said, "On request". I sheepishly said "My apologies. Student pilot here. What does 'On request' mean?". I got the barely patient reply of "I have your departure on request, and will let you know when I can grant you clearance." In hindsight, it would have been nice for an instructor to have mentioned this to me.

***And now, forgive me for some thread drift***

I'm glad that gliders were mentioned. I wish all ATC and other VFR pilots were more aware of "us". Something like what I write below should be known to all pilots.

Gliders are usually searching for ways to stay up. As far as ATC is concerned, even if they do see us, they usually don't know the pilot's intent. Because in many cases, even the pilot doesn't know his own intent other than something vague like they are "trying to head north-west to the next mountain". Their desired altitude is "as high as I can get up to 17,999" and their desired and actual heading is constantly changing based on dozens of shifting variables. Picture a bunch of racoons wandering about on the freeway. As far as radio is concerned, they are usually on 123.3 talking to other glider pilots and switch to Unicom only when landing. When ATC do see us, and call us out to other pilots, it is usually "aircraft 2 miles south of you, at unknown altitude and unknown intent".

While they do obey VFR rules, they rarely fly straight and level. Consequently, they can almost NEVER obey the VFR +500' guideline. They generally fly a consistent speed, not a consistent altitude. They wiggle and turn unexpectedly, in search of chasing upward air masses. While I have an 18-meter wingspan, my wings are as thick as a tennis ball. You can't see a tennis ball from 200 yards, so you can't see my wings either. My fuselage is tiny. Maybe 2' wide, and 3' high at best. If we are flying in wave (on the upwind side of a lenticular cloud), we might be doing something like 145 knots, an heading straight for you. Some have Mode C transponders (even though they are not required), some are radio only, some have nothing. Most are fiberglass, and won't show up on radar. There are many more out there than you or ATC think. They sometimes (frequently, cough, cough :rolleyes:) unwisely skulk just under cloud base, ignoring the 1000' cloud separation rule, because that is where the lift is frequently best. They fly WAY outside the areas marked as glider areas on sectionals. Those locations are where they tend to tow from or land, but might do a 1000k out and return flight to anywhere. So if you want to know where they are, put a 500-kilometer ring around each glider symbol you see. They fly from <100' AGL (while ridge running), all the way up to 17,999 MSL and fly in Class B through G (Only in Class A when given permission). They are usually hyper-aware of see-and-avoid because they know there are other planes and other glider pilots out there. But like any other pilot, they can't be perfect and sometimes have cockpit distractions.

I am not aware of a single glider pilot that hasn't had at least one near miss with power traffic who didn't even know they were there after they passed by. I personally recall several instances of Cessna Citations (my favorite) flying by, where I could actually see the pilot reading a newspaper. They might be IFR, but that doesn't mean everyone else is. I wish they would read this.

Even though we are lighter, if we touch, we both lose. So please be aware, and keep an eye outside, even if you have ADSB (gliders have an ADSB exemption :eek: ).
 
Last edited:
I am not aware of a single glider pilot that hasn't had at least one near miss with power traffic who didn't even know they were there after they passed by. I personally recall several instances of Cessna Citations (my favorite) flying by, where I could actually see the pilot reading a newspaper. They might be IFR, but that doesn't mean everyone else is. I wish they would read this.

Many forget, or don't even know, that ATC's obligation in the IFR environment is to provide separation between IFR aircraft. It is the pilots responsibility to separate from VFR traffic. It's easy to lose site of this fact, as ATC seems to take responsibility for VFR separation. However, it is not an obligation, according to the FAR's. The rules assume that VFR traffic won't exist in IMC. However, I suspect most IFR pilots have had VFR conflicts in IMC. I know I have.

Larry
 
Many forget, or don't even know, that ATC's obligation in the IFR environment is to provide separation between IFR aircraft. It is the pilots responsibility to separate from VFR traffic. It's easy to lose site of this fact, as ATC seems to take responsibility for VFR separation. However, it is not an obligation, according to the FAR's. The rules assume that VFR traffic won't exist in IMC. However, I suspect most IFR pilots have had VFR conflicts in IMC. I know I have.

Larry

And I'm sure that some pilots on IFR flight plans forget that they are obligated to look out the window in VMC, one of whom is the Citation pilot reading the newspaper.:eek:
 
All of the mention of gliders on radar here reminds me of my visit to the local FSS back in August. We have a jump zone at a nearby airport and they regularly watch the jumpers (meatsacs as one specialist like to call them) show up on the radar. I got the opportunity to see it for myself, we watched the jump plane climb up and then the 8 targets appear near it. We tracked the jumpers all the way down to the radar cut off at 2000 AGL or so. (The radar isn't local, we were watching a relay from Calgary ~60NM to the south)
 
And I'm sure that some pilots on IFR flight plans forget that they are obligated to look out the window in VMC, one of whom is the Citation pilot reading the newspaper.:eek:

This one probably wasn't reading the paper, but were not aware of VFR glider traffic while descending into Reno

This picture shows the glider spar still in the forward fuselage of the Hawker jet!

https://www.flickr.com/photos/jzawodn/228637332/

More pictures here -

http://jeremy.zawodny.com/blog/archives/007288.html

The visiting Japanese glider pilot bailed out (plane fell apart around him?) and all were basically uninjured.

https://app.ntsb.gov/pdfgenerator/R...=20060906X01297&AKey=1&RType=Summary&IType=FA
 
"they added something like 5,500' upon request"

As some have stated, he most probably said "on request", a common phrase from Center controllers.

Occasionally you'll hear a more self explanatory " I HAVE YOUR request" from the controller when you're asking for an altitude, weather deviation, etc. Just another way of saying the same thing - that I'm working on it, just stand by.

As any instructor, or in this case someone more familiar with the IFR environment, will tell you; if you don't understand your clearance, just ask for clarification. Avoids embarrassment or worse down the road.

Doug
Seattle area
 
UP vs. Down

I guess it is clear now... since many have replied. But I feel obligated to mention...
UP is UP, DOWN is DOWN. As pilots, I suspect we never get those two mixed up.
ON REQUEST and UPON REQUEST. Not even close to the same meaning.
One thing I found of use while training for the instrument instructor rating was keeping a portable with me and tuning various controllers just to absorb all the phrases. And yes, there are regional differences and habits, though "standard" is supposed to be just that.
At times, living near a student center (ERAU) I get a laugh at things like: " I am beaming the tower" Instead of abeam. And "holding short of runway 21L" while clear back at the run up area. I do refrain from keying the mic and saying "yeah, WAY short of the runway". That would just be rude.
The forums are such a good resource in this day and age. And Doug's is civilized to boot. Can't ask for much more than that.
 
ON REQUEST and UPON REQUEST. Not even close to the same meaning.

Actually, it's context-dependent, and they can mean almost the exact same thing.

I got on the horse.
I got upon the horse.

Upon may be slightly preferred when the context indicates a temporal or motive event.

This bill is payable upon receipt.

But it's really subtle, and they're almost interchangeable. What you're looking at is a form of informal fallacy known as equivocation...

Your preferred altitude is upon request. (Does it mean they have the request, or as the OP thought, that it was available upon request by the pilot?).
 
Many forget, or don't even know, that ATC's obligation in the IFR environment is to provide separation between IFR aircraft.
Larry

IFR separation is always expected. I think what happens is that on VMC days we get accustomed to advisories of VFR traffic. Dang gliders are pretty [optically] stealthy when they are at your altitude. I saw the guy but by the time I sorted out what I was seeing I was on him. Or is it upon him? Lesson learned...
 
Back
Top